WorldWideScience

Sample records for natural systems discontinuities

  1. System dynamics with interaction discontinuity

    CERN Document Server

    Luo, Albert C J

    2015-01-01

    This book describes system dynamics with discontinuity caused by system interactions and presents the theory of flow singularity and switchability at the boundary in discontinuous dynamical systems. Based on such a theory, the authors address dynamics and motion mechanism of engineering discontinuous systems due to interaction. Stability and bifurcations of fixed points in nonlinear discrete dynamical systems are presented, and mapping dynamics are developed for analytical predictions of periodic motions in engineering discontinuous dynamical systems. Ultimately, the book provides an alternative way to discuss the periodic and chaotic behaviors in discontinuous dynamical systems.

  2. Characterization of discontinuity systems in gneiss formation

    International Nuclear Information System (INIS)

    Kim, Jhin Wung; Kang, Byoung Moo; Rhee, Chan Goo

    1990-05-01

    Suitability evaluation for the site of radioactive waste disposal includes the consideration on rock mass stability and groundwater flow condition, which reflects the attitude of discontinuities present in rock. The research work was done to develop the objective descriptive method and analysing techniques for the discontinuity system and to enhance techniques for predicting the extent of the system in subsurface. A descriptive method for evaluating discontinuities in gneissic rock mass was established. The distribution of discontinuities were analysed based on geometric, mechanical, and hydrogeological parameters. The various parameters of discontinuties were collected based on rock type, discontinuites were collection and plunge, trace length, roughness, aperture type. The three dimensional distribution and orientation of the system were synthesized. The results indicate that the discontinuities are composed of 3 major sets. The frequency, concentrations, spacings, trace lengths, and the interconnectivity index were estimated for the three sets. The frequency depends on depth but abnormal high frequency zone also exists. (author)

  3. Discontinuity and complexity in nonlinear physical systems

    CERN Document Server

    Baleanu, Dumitru; Luo, Albert

    2014-01-01

    This unique book explores recent developments in experimental research in this broad field, organized in four distinct sections. Part I introduces the reader to the fractional dynamics and Lie group analysis for nonlinear partial differential equations. Part II covers chaos and complexity in nonlinear Hamiltonian systems, important to understand the resonance interactions in nonlinear dynamical systems, such as Tsunami waves and wildfire propagations; as well as Lev flights in chaotic trajectories, dynamical system synchronization and DNA information complexity analysis. Part III examines chaos and periodic motions in discontinuous dynamical systems, extensively present in a range of systems, including piecewise linear systems, vibro-impact systems and drilling systems in engineering. And in Part IV, engineering and financial nonlinearity are discussed. The mechanism of shock wave with saddle-node bifurcation and rotating disk stability will be presented, and the financial nonlinear models will be discussed....

  4. The Nature and Determinants of Intranet Discontinuance after Mandatory Adoption

    Science.gov (United States)

    Cho, Inho

    2008-01-01

    This research examines post-adoption behavior (discontinuance versus continuance) with the context of Intranet use. Multiple theories are used as theoretical frameworks to extend information communication technology research to the case of post-adoption behavior. Three research questions and six sets of hypotheses are formulated to distinguish…

  5. A trend discontinuity: The mystery of natural gas prices

    International Nuclear Information System (INIS)

    Steffes, D.W.

    1995-01-01

    For the last fifteen years, the natural gas price forecasting experts have had a terrible record of forecasting future natural gas prices. (In the early 80's, the gas price was forecasted to be over $10/MMBtu in the late 80's). To make matters even worse, they can't seem to understand why the price is what it is, even in hindsight. If these experts can't even get it right in hindsight, how can one ever expect to get it right in foresight? It is concluded that the traditional laws of supply and demand don't work very well in this new quasi-regulated natural gas industry. Evidently, Social Influences and Political Influences are more important than the Economic Influence on natural gas prices

  6. State and data techniques for control of discontinuous systems

    International Nuclear Information System (INIS)

    Kisner, R.A.

    1986-01-01

    This paper describes a technique for structured analysis and design of automated control systems. The technique integrates control of continuous and discontinuous nuclear power plant subsystems and components. A hierarchical control system with distributed intelligence follows from applying the technique. Further, it can be applied to all phases of control system design. For simplicity, the example used in the paper is limited to phase 1 design (basic automatic control action), in which no maintenance, testing, or contingency capability is attempted. 11 figs

  7. A New Stochastic Approach to Predict Peak and Residual Shear Strength of Natural Rock Discontinuities

    Science.gov (United States)

    Casagrande, D.; Buzzi, O.; Giacomini, A.; Lambert, C.; Fenton, G.

    2018-01-01

    Natural discontinuities are known to play a key role in the stability of rock masses. However, it is a non-trivial task to estimate the shear strength of large discontinuities. Because of the inherent complexity to access to the full surface of the large in situ discontinuities, researchers or engineers tend to work on small-scale specimens. As a consequence, the results are often plagued by the well-known scale effect. A new approach is here proposed to predict shear strength of discontinuities. This approach has the potential to avoid the scale effect. The rationale of the approach is as follows: a major parameter that governs the shear strength of a discontinuity within a rock mass is roughness, which can be accounted for by surveying the discontinuity surface. However, this is typically not possible for discontinuities contained within the rock mass where only traces are visible. For natural surfaces, it can be assumed that traces are, to some extent, representative of the surface. It is here proposed to use the available 2D information (from a visible trace, referred to as a seed trace) and a random field model to create a large number of synthetic surfaces (3D data sets). The shear strength of each synthetic surface can then be estimated using a semi-analytical model. By using a large number of synthetic surfaces and a Monte Carlo strategy, a meaningful shear strength distribution can be obtained. This paper presents the validation of the semi-analytical mechanistic model required to support the new approach for prediction of discontinuity shear strength. The model can predict both peak and residual shear strength. The second part of the paper lays the foundation of a random field model to support the creation of synthetic surfaces having statistical properties in line with those of the data of the seed trace. The paper concludes that it is possible to obtain a reasonable estimate of peak and residual shear strength of the discontinuities tested from the

  8. Natural composite in austenitic alloys with a structure of the complete discontinuous decomposition

    International Nuclear Information System (INIS)

    Zemtsova, N.D.; Anufrieva, E.I.; Uvarov, A.I.; Vasechkina, T.P.; Sandovskij, V.A.

    2002-01-01

    The papers are reviewed on heat treatment conditions resulting in a 100% degree of discontinuous precipitation in austenite on ageing metastable Fe-Ni-Ti alloys (N2KhT2, N26T3, N25T5, N24Kh2T3, N29T3, N29KhT3, N26Kh5T3). Mechanical properties and structure of the alloys are investigated after various heat and thermomechanical treatments. It is revealed that discontinuous precipitation is accomplished by way of migration of low-angle boundaries as the matrix is supersaturated essentially with alloying elements. The alloys with the structure of 100% discontinuous precipitation can be treated as natural composites consisting of alternating plates of intermetallic compound and austenite. Temperature dependences of strength and plastic properties of a composite material and a hardened alloy are compared [ru

  9. Discontinuous Galerkin Methods for NonLinear Differential Systems

    Science.gov (United States)

    Barth, Timothy; Mansour, Nagi (Technical Monitor)

    2001-01-01

    This talk considers simplified finite element discretization techniques for first-order systems of conservation laws equipped with a convex (entropy) extension. Using newly developed techniques in entropy symmetrization theory, simplified forms of the discontinuous Galerkin (DG) finite element method have been developed and analyzed. The use of symmetrization variables yields numerical schemes which inherit global entropy stability properties of the PDE (partial differential equation) system. Central to the development of the simplified DG methods is the Eigenvalue Scaling Theorem which characterizes right symmetrizers of an arbitrary first-order hyperbolic system in terms of scaled eigenvectors of the corresponding flux Jacobian matrices. A constructive proof is provided for the Eigenvalue Scaling Theorem with detailed consideration given to the Euler equations of gas dynamics and extended conservation law systems derivable as moments of the Boltzmann equation. Using results from kinetic Boltzmann moment closure theory, we then derive and prove energy stability for several approximate DG fluxes which have practical and theoretical merit.

  10. Cryogenic thermal storage system for discontinuous industrial vacuum processes

    Directory of Open Access Journals (Sweden)

    Scaringella M.

    2012-10-01

    Full Text Available Phase Change Materials are proposed for refrigerating systems in discontinuous industrial vacuum processes where temperatures as low as −140 ÷ −100°C are necessary within time-frames representing 10÷20% of total operating time. An application is proposed for cooling systems used in a Physical Vapour Deposition (PVD apparatus. A prototype has been manufactured which couples a cryopump with a reservoir filled with MethylCycloPentane (MCP-C6H12 and a distribution line where nitrogen in the gaseous state is flowing. Preliminary tests show that temperatures of about −120°C are actually achieved within time windows compatible with PVD applications.

  11. Continuous, saturation, and discontinuous tokamak plasma vertical position control systems

    Energy Technology Data Exchange (ETDEWEB)

    Mitrishkin, Yuri V., E-mail: y_mitrishkin@hotmail.com [M. V. Lomonosov Moscow State University, Faculty of Physics, Moscow 119991 (Russian Federation); Pavlova, Evgeniia A., E-mail: janerigoler@mail.ru [M. V. Lomonosov Moscow State University, Faculty of Physics, Moscow 119991 (Russian Federation); Kuznetsov, Evgenii A., E-mail: ea.kuznetsov@mail.ru [Troitsk Institute for Innovation and Fusion Research, Moscow 142190 (Russian Federation); Gaydamaka, Kirill I., E-mail: k.gaydamaka@gmail.com [V. A. Trapeznikov Institute of Control Sciences of the Russian Academy of Sciences, Moscow 117997 (Russian Federation)

    2016-10-15

    Highlights: • Robust new linear state feedback control system for tokamak plasma vertical position. • Plasma vertical position relay control system with voltage inverter in sliding mode. • Design of full models of multiphase rectifier and voltage inverter. • First-order unit approximation of full multiphase rectifier model with high accuracy. • Wider range of unstable plant parameters of stable control system with multiphase rectifier. - Abstract: This paper is devoted to the design and comparison of unstable plasma vertical position control systems in the T-15 tokamak with the application of two types of actuators: a multiphase thyristor rectifier and a transistor voltage inverter. An unstable dynamic element obtained by the identification of plasma-physical DINA code was used as the plasma model. The simplest static feedback state space control law was synthesized as a linear combination of signals accessible to physical measurements, namely the plasma vertical displacement, the current, and the voltage in a horizontal field coil, to solve the pole placement problem for a closed-loop system. Only one system distinctive parameter was used to optimize the performance of the feedback system, viz., a multiple real pole. A first-order inertial unit was used as the rectifier model in the feedback. A system with a complete rectifier model was investigated as well. A system with the voltage inverter model and static linear controller was brought into a sliding mode. As this takes place, real time delays were taken into account in the discontinuous voltage inverter model. The comparison of the linear and sliding mode systems showed that the linear system enjoyed an essentially wider range of the plant model parameters where the feedback system was stable.

  12. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Science.gov (United States)

    2010-07-01

    ... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts and... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers from...

  13. Simplified Discontinuous Galerkin Methods for Systems of Conservation Laws with Convex Extension

    Science.gov (United States)

    Barth, Timothy J.

    1999-01-01

    Simplified forms of the space-time discontinuous Galerkin (DG) and discontinuous Galerkin least-squares (DGLS) finite element method are developed and analyzed. The new formulations exploit simplifying properties of entropy endowed conservation law systems while retaining the favorable energy properties associated with symmetric variable formulations.

  14. Identification of a Discontinuous Parameter in Stochastic Parabolic Systems

    International Nuclear Information System (INIS)

    Aihara, S. I.

    1998-01-01

    The purpose of this paper is to study the identification problem for a spatially varying discontinuous parameter in stochastic diffusion equations. The consistency property of the maximum likelihood estimate (M.L.E.) and a generating algorithm for M.L.E. have been explored under the condition that the unknown parameter is in a sufficiently regular space with respect to spatial variables. In order to prove the consistency property of the M.L.E. for a discontinuous diffusion coefficient, we use the method of sieves, i.e., first the admissible class of unknown parameters is projected into a finite-dimensional space and next the convergence of the derived finite-dimensional M.L.E. to the infinite-dimensional M.L.E. is justified under some conditions. An iterative algorithm for generating the M.L.E. is also proposed with two numerical examples

  15. NATURAL COURSE OF PATIENTS DISCONTINUING TREATMENT FOR AGE-RELATED MACULAR DEGENERATION AND FACTORS ASSOCIATED WITH VISUAL PROGNOSIS.

    Science.gov (United States)

    Kim, Jae Hui; Chang, Young Suk; Kim, Jong Woo

    2017-12-01

    To evaluate the 24-month natural course of visual changes in patients discontinuing treatment despite persistent or recurrent fluid and factors predictive of visual prognosis. This retrospective, observational study included 35 patients (35 eyes) who initially received anti-vascular endothelial growth factor treatment for neovascular age-related macular degeneration (AMD), but discontinued treatment despite persistent or recurrent fluid. The best-corrected visual acuity (BCVA) at treatment discontinuation was determined and compared with the 24-month BCVA, which was then compared between polypoidal choroidal vasculopathy and other neovascular age-related macular degeneration subtypes. Baseline characteristics predictive of visual outcome and the degree of visual change were also analyzed. The mean number of anti-vascular endothelial growth factor injections before treatment discontinuation was 4.0 ± 1.6. The mean logarithm of minimal angle of resolution of BCVA at treatment discontinuation and that at 24 months were 1.02 ± 0.20 (Snellen equivalents = 20/209) and 1.60 ± 0.56 (20/796), respectively (P macular degeneration subtypes (P = 0.803). The type of fluid (intraretinal fluid vs. no intraretinal fluid) was predictive of 24-month BCVA (P = 0.004) and the degree of changes in BCVA (P = 0.043). Marked deterioration in visual acuity was noted in patients discontinuing treatment, regardless of neovascular age-related macular degeneration subtypes. The presence of intraretinal fluid was associated with worse visual prognosis, suggesting that patients with intraretinal fluid should be strongly warned about their poor prognosis before they decide to discontinue treatment.

  16. 78 FR 8407 - Authorization To Manufacture and Distribute Postage Evidencing Systems; Discontinued Indicia

    Science.gov (United States)

    2013-02-06

    ... MANUFACTURE AND DISTRIBUTE POSTAGE EVIDENCING SYSTEMS 0 1. The authority citation for 39 CFR part 501... POSTAL SERVICE 39 CFR Part 501 Authorization To Manufacture and Distribute Postage Evidencing Systems; Discontinued Indicia AGENCY: Postal Service TM . ACTION: Final rule. SUMMARY: The Postal Service...

  17. 77 FR 41336 - Authorization to Manufacture and Distribute Postage Evidencing Systems; Discontinued Indicia

    Science.gov (United States)

    2012-07-13

    ... MANUFACTURE AND DISTRIBUTE POSTAGE EVIDENCING SYSTEMS 1. The authority citation for 39 CFR part 501 continues... POSTAL SERVICE 39 CFR Part 501 Authorization to Manufacture and Distribute Postage Evidencing Systems; Discontinued Indicia AGENCY: Postal Service\\TM\\. ACTION: Proposed rule. SUMMARY: The Postal...

  18. Continuities and Discontinuities in Accounting Systems: 1998 Survey of ASBO International Membership in North America.

    Science.gov (United States)

    Henstock, Thomas F.

    1999-01-01

    Based on a survey of Association of School Business Officials members, this article focuses on 10 accounting system modules and how respondents felt about their system's operation and integration. Results showed solid continuity among general ledger, accounts payable, and payroll modules and discontinuities among fixed-asset and student accounting…

  19. Arbitrary number of limit cycles for planar discontinuous piecewise linear differential systems with two zones

    Directory of Open Access Journals (Sweden)

    Denis de Carvalho Braga

    2015-09-01

    Full Text Available For any given positive integer $n$ we show the existence of a class of discontinuous piecewise linear differential systems with two zones in the plane having exactly $n$ hyperbolic limit cycles. Moreover, all the points on the separation boundary between the two zones are of sewing type, except the origin which is the only equilibrium point.

  20. Modeling of Multicomponent Diffusions and Natural Convection in Unfractured and Fractured Media by Discontinuous Galerkin and Mixed Methods

    KAUST Repository

    Hoteit, Hussein

    2017-12-29

    Computation of the distribution of species in hydrocarbon reservoirs from diffusions (thermal, molecular, and pressure) and natural convection is an important step in reservoir initialization. Current methods, which are mainly based on the conventional finite difference approach, may not be numerically efficient in fractured and other media with complex heterogeneities. In this work, the discontinuous Galerkin (DG) method combined with the mixed finite element (MFE) method is used for the calculation of compositional variation in fractured hydrocarbon reservoirs. The use of unstructured gridding allows efficient computations for fractured media when the crossflow equilibrium concept is invoked. The DG method has less numerical dispersion than the upwind finite difference (FD) methods. The MFE method ensures continuity of fluxes at the interface of the grid elements. We also use the local discontinuous Galerkin (LDG) method instead of the MFE calculate the diffusion fluxes. Results from several numerical examples are presented to demonstrate the efficiency, robustness, and accuracy of the model. Various features of convection and diffusion in homogeneous, layered, and fractured media are also discussed.

  1. The system of nature

    CERN Document Server

    D'Holbac, Baron

    1999-01-01

    "The source of Man's unhappiness is his ignorance of Nature."D'Holbach believed that the misery he saw in mankind around him was caused by religion and its superstitious beliefs - that there was a God who controlled destiny and would reward or punish individuals. The System of Nature was written to replace these delusions with a schema of understanding based solely on the physical workings of nature. "Let Man study this nature, let him learn her laws, contemplate her energies." For d'Holbach the soul is only the physical body, understood from a certain point of view, which dies when the body dies. All the events and the nature of the world can be understood in terms of the motion and properties of matter; even the tiniest causes contribute to huge events - a simple change in the diet of an Emperor (or some other such insignificant cause), he suggests might have been capable of "saving kingdoms." For him, nature's laws are fixed and necessary, and if Man wants to find happiness it is best to accept this - if g...

  2. 78 FR 59754 - Notice of Application for Approval of Discontinuance or Modification of a Railroad Signal System

    Science.gov (United States)

    2013-09-27

    ..., LLC, Ms. Rhonda Nicoloff, Managing Member, 1505 South Redwood Road, Salt Lake City, UT 84104. GRYR seeks approval of the proposed discontinuance and removal of the automatic block signal (ABS) system...

  3. A contactless positioning system for monitoring discontinuities in three dimensions with geological and geotechnical applications

    Czech Academy of Sciences Publication Activity Database

    Rinaldi-Montes, N.; Rowberry, Matthew David; Frontera, C.; Baroň, I.; Garcés, G.; Blahůt, Jan; Pérez-López, R.; Pennos, C.; Martí, Xavier

    2017-01-01

    Roč. 88, č. 7 (2017), č. článku 074501. ISSN 0034-6748 R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985891 ; RVO:68378271 Keywords : mechanical discontinuities * contactless positioning system * magnetoresistive sensing * geotechnical engineering * structural health monitoring Subject RIV: JB - Sensors, Measurment, Regulation; BM - Solid Matter Physics ; Magnetism (FZU-D) OBOR OECD: Environmental and geological engineering , geotechnics; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D) Impact factor: 1.515, year: 2016

  4. Discontinuous nature of the repulsive-to-attractive colloidal glass transition

    NARCIS (Netherlands)

    De Laar, Van T.; Higler, R.; Schroën, K.; Sprakel, J.

    2016-01-01

    In purely repulsive colloidal systems a glass transition can be reached by increasing the particle volume fraction beyond a certain threshold. The resulting glassy state is governed by configurational cages which confine particles and restrict their motion. A colloidal glass may also be formed by

  5. Characterizing volumetric discontinuities present in NPP heat exchangers with EASY: an eddy current data analysis system

    International Nuclear Information System (INIS)

    Alencar, Donizete A.; Silva Junior, Silverio F.

    2011-01-01

    Eddy current is a very important NDT inspection method widely used to perform integrity evaluation of tubes installed in heat exchangers. For nuclear power plants, a classical example is the remote inspection of steam generators and condensers, as well as other ordinary auxiliary equipment. Data evaluation can be performed by means of precise phase and amplitude measurements of complex impedance signals, represented as Lissajous figures plotted on the screen of the inspection systems. This paper presents the software EASY, a computer assisted analysis system developed at CDTN to help the characterization of volumetric discontinuities present in heat exchangers tubes. Data to be analyzed are obtained from commercial eddy current equipment data file, such as ECT MAD8D. Main advantage of that system is its portability and easy use, since it can be executed in ordinary PC, under Microsoft Windows operating system. (author)

  6. Management applications of discontinuity theory

    Science.gov (United States)

    Angeler, David G.; Allen, Craig R.; Barichievy, Chris; Eason, Tarsha; Garmestani, Ahjond S.; Graham, Nicholas A.J.; Granholm, Dean; Gunderson, Lance H.; Knutson, Melinda; Nash, Kirsty L.; Nelson, R. John; Nystrom, Magnus; Spanbauer, Trisha; Stow, Craig A.; Sundstrom, Shana M.

    2015-01-01

    Human impacts on the environment are multifaceted and can occur across distinct spatiotemporal scales. Ecological responses to environmental change are therefore difficult to predict, and entail large degrees of uncertainty. Such uncertainty requires robust tools for management to sustain ecosystem goods and services and maintain resilient ecosystems.We propose an approach based on discontinuity theory that accounts for patterns and processes at distinct spatial and temporal scales, an inherent property of ecological systems. Discontinuity theory has not been applied in natural resource management and could therefore improve ecosystem management because it explicitly accounts for ecological complexity.Synthesis and applications. We highlight the application of discontinuity approaches for meeting management goals. Specifically, discontinuity approaches have significant potential to measure and thus understand the resilience of ecosystems, to objectively identify critical scales of space and time in ecological systems at which human impact might be most severe, to provide warning indicators of regime change, to help predict and understand biological invasions and extinctions and to focus monitoring efforts. Discontinuity theory can complement current approaches, providing a broader paradigm for ecological management and conservation.

  7. The bioethanol from bagasse with the approach of discontinuous systems and the delay phenomena

    International Nuclear Information System (INIS)

    Albernas Carvajal, Yailet; Gonzalez Cortes, Meilyn; Mesa Garriga, Leyanis; Pedraza Garciga, Julio; Gonzalez Suarez, Erenio

    2011-01-01

    In this paper was analyzed the Bioethanol technology from bagasse considering discontinuous systems' and the delay phenomena. This technology have two stages that are key to succeed in obtaining the fermentable sugars, they are the pretreatment stage and enzymatic hydrolysis for subsequent fermentation. The great obstacle of the two latter stages, is that for best results, need long residence times (and this is where the delay phenomena it appears). For that reason the analysis require a study on how to carry out to ensure that the process global continuous. The enzymatic hydrolysis stage last an average of 24 h, while fermentation stage is accomplishes in 12 h. In this paper, the bioethanol technology was studied taking into account the basic concepts of discontinuous systems. Different technological configurations were studied, obtaining the best configuration: the presaccharification process, according to technical and economics criterions. The process profitability is achieved considering the total process as a bio refinery, which allows the production of high added value by-products such as furfural. (author)

  8. A contactless positioning system for monitoring discontinuities in three dimensions with geological and geotechnical applications.

    Science.gov (United States)

    Rinaldi-Montes, Natalia; Rowberry, Matt; Frontera, Carlos; Baroň, Ivo; Garcés, Javier; Blahůt, Jan; Pérez-López, Raúl; Pennos, Christos; Martí, Xavi

    2017-07-01

    In this paper, a contactless positioning system is presented which has been designed to monitor the kinematic behavior of mechanical discontinuities in three dimensions. The positioning system comprises a neodymium magnet, fixed on one side of a discontinuity, and a magnetoresistive sensing array, fixed on the opposing side. Each of the anisotropic magnetoresistive sensors in the sensing array records the magnetic field along three orthogonal directions. The positioning system intrinsically generates compact data packages which are transmitted effectively using a range of standard wireless telecommunication technologies. These data are then modeled using a global least squares fitting procedure in which the adjustable parameters are represented by the position and orientation of the neodymium magnet. The instrumental resolution of the positioning system can be tuned depending on the strength of the magnetic field generated by the neodymium magnet and the distance between the neodymium magnet and the magnetoresistive sensing array. For a typical installation, the displacement resolution is shown to be circa 10 μm while the rotation resolution is circa 0.1°. The first permanently deployed positioning system was established in June 2016 to monitor the behavior of an N-S trending fault located at the contact between the eastern Alps and the Vienna Basin. The robust design of the positioning system is demonstrated by the fact that no interruptions in the broadcasted data streams have occurred since its installation. It has a range of potential applications in many areas of basic and applied research including geology, geotechnical engineering, and structural health monitoring.

  9. A contactless positioning system for monitoring discontinuities in three dimensions with geological and geotechnical applications

    Science.gov (United States)

    Rinaldi-Montes, Natalia; Rowberry, Matt; Frontera, Carlos; BaroÅ, Ivo; Garcés, Javier; Blahůt, Jan; Pérez-López, Raúl; Pennos, Christos; Martí, Xavi

    2017-07-01

    In this paper, a contactless positioning system is presented which has been designed to monitor the kinematic behavior of mechanical discontinuities in three dimensions. The positioning system comprises a neodymium magnet, fixed on one side of a discontinuity, and a magnetoresistive sensing array, fixed on the opposing side. Each of the anisotropic magnetoresistive sensors in the sensing array records the magnetic field along three orthogonal directions. The positioning system intrinsically generates compact data packages which are transmitted effectively using a range of standard wireless telecommunication technologies. These data are then modeled using a global least squares fitting procedure in which the adjustable parameters are represented by the position and orientation of the neodymium magnet. The instrumental resolution of the positioning system can be tuned depending on the strength of the magnetic field generated by the neodymium magnet and the distance between the neodymium magnet and the magnetoresistive sensing array. For a typical installation, the displacement resolution is shown to be circa 10 μm while the rotation resolution is circa 0.1°. The first permanently deployed positioning system was established in June 2016 to monitor the behavior of an N-S trending fault located at the contact between the eastern Alps and the Vienna Basin. The robust design of the positioning system is demonstrated by the fact that no interruptions in the broadcasted data streams have occurred since its installation. It has a range of potential applications in many areas of basic and applied research including geology, geotechnical engineering, and structural health monitoring.

  10. Organising medication discontinuation

    DEFF Research Database (Denmark)

    Nixon, Michael; Kousgaard, Marius Brostrøm

    2016-01-01

    Background: Discontinuing medications is a complex decision making process and an important medical practice. It is a tool in reducing polypharmacy, reducing health system expenditure and improving patient quality of life. Few studies have looked at how general practitioners (GPs) discontinue a m...

  11. Identifying and quantifying medication errors: evaluation of rapidly discontinued medication orders submitted to a computerized physician order entry system.

    Science.gov (United States)

    Koppel, Ross; Leonard, Charles E; Localio, A Russell; Cohen, Abigail; Auten, Ruthann; Strom, Brian L

    2008-01-01

    All methods of identifying medication prescribing errors are fraught with inaccuracies and systematic bias. A systematic, efficient, and inexpensive way of measuring and quantifying prescribing errors would be a useful step for reducing them. We ask if rapid discontinuations of prescription-orders--where physicians stop their orders within 2 hours--would be an expedient proxy for prescribing errors? To study this we analyzed CPOE-system medication orders entered and then discontinued within 2 hours. We investigated these phenomena in real time via interviews with corresponding ordering physicians. Each order was also independently reviewed by a clinical pharmacist or physicians. We found that of 114 rapidly discontinued orders by 75 physicians, two-thirds (35 of 53, PPV = 66; 95% CI = 53-77) of medication orders discontinued within 45 minutes were deemed inappropriate (overdose, underdose, etc.). Overall, 55% (63 of 114; 95% CI = 46-64%) of medication orders discontinued within 2 hours were deemed inappropriate. This measure offers a rapid, constant, inexpensive, and objective method to identify medication orders with a high probability of error. It may also serve as a screening and teaching mechanism for physicians-in-training.

  12. A one-level FETI method for the drift–diffusion-Poisson system with discontinuities at an interface

    KAUST Repository

    Baumgartner, Stefan

    2013-06-01

    A 3d feti method for the drift-diffusion-Poisson system including discontinuities at a 2d interface is developed. The motivation for this work is to provide a parallel numerical algorithm for a system of PDEs that are the basic model equations for the simulation of semiconductor devices such as transistors and sensors. Moreover, discontinuities or jumps in the potential and its normal derivative at a 2d surface are included for the simulation of nanowire sensors based on a homogenized model. Using the feti method, these jump conditions can be included with the usual numerical properties and the original Farhat-Roux feti method is extended to the drift-diffusion-Poisson equations including discontinuities. We show two numerical examples. The first example verifies the correct implementation including the discontinuities on a 2d grid divided into eight subdomains. The second example is 3d and shows the application of the algorithm to the simulation of nanowire sensors with high aspect ratios. The Poisson-Boltzmann equation and the drift-diffusion-Poisson system with jump conditions are solved on a 3d grid with real-world boundary conditions. © 2013 Elsevier Inc..

  13. Early discontinuation

    DEFF Research Database (Denmark)

    Hansen, Dorte Gilså; Felde, Lina; Gichangi, Anthony

    2007-01-01

    Introduction Discontinuation of medical drug treatment is a serious problem in primary care. The need for a better understanding of the processes, including physician-specific mechanisms, is apparent. The aim of this study was to analyse the association between general practitioners' prescribing....... There was a positive association between the prevalence of prescribing for the specific drugs studied (antidepressants, antidiabetics, drugs against osteoporosis and lipid-lowering drugs) and early discontinuation (r = 0.29 -0.44), but not for anti-hypertensive drugs. The analysis of the association between prevalence...... of all drugs and drug-specific early discontinuation showed some degree of positive association - strongest for anti-hypertensive drugs (r = 0.62) and antidepressants (r = 0.43). Conclusion This study confirmed our hypothesis that general practitioners with high levels of prescribing attain higher rates...

  14. Management applications of discontinuity theory | Science ...

    Science.gov (United States)

    1.Human impacts on the environment are multifaceted and can occur across distinct spatiotemporal scales. Ecological responses to environmental change are therefore difficult to predict, and entail large degrees of uncertainty. Such uncertainty requires robust tools for management to sustain ecosystem goods and services and maintain resilient ecosystems. 2.We propose an approach based on discontinuity theory that accounts for patterns and processes at distinct spatial and temporal scales, an inherent property of ecological systems. Discontinuity theory has not been applied in natural resource management and could therefore improve ecosystem management because it explicitly accounts for ecological complexity. 3.Synthesis and applications. We highlight the application of discontinuity approaches for meeting management goals. Specifically, discontinuity approaches have significant potential to measure and thus understand the resilience of ecosystems, to objectively identify critical scales of space and time in ecological systems at which human impact might be most severe, to provide warning indicators of regime change, to help predict and understand biological invasions and extinctions and to focus monitoring efforts. Discontinuity theory can complement current approaches, providing a broader paradigm for ecological management and conservation This manuscript provides insight on using discontinuity approaches to aid in managing complex ecological systems. In part

  15. A computational model of insect discontinuous gas exchange: A two-sensor, control systems approach.

    Science.gov (United States)

    Grieshaber, Beverley J; Terblanche, John S

    2015-06-07

    The insect gas exchange system is characterised by branching air-filled tubes (tracheae/tracheoles) and valve-like structures in their outer integument (spiracles) which allow for a periodic gas exchange pattern known as the discontinuous gas exchange cycle (DGC). The DGC facilitates the temporal decoupling of whole animal gas exchange from cellular respiration rates and may confer several physiological benefits, which are nevertheless highly controversial (primarily reduction of cellular oxidative damage and/or respiratory water saving). The intrinsic and extrinsic factors influencing DGCs are the focus of extensive ongoing research and little consensus has been reached on the evolutionary genesis or mechanistic costs and benefits of the pattern. Despite several hypotheses and much experimental and evolutionary biology research, a mechanistic physical model, which captures various key elements of the DGC pattern, is currently lacking. Here, we present a biologically realistic computational, two-sensor DGC model (pH/carbon dioxide and oxygen setpoints) for an Orthopteran gas exchange system, and show computationally for the first time that a control system of two interacting feedback loops is capable of generating a full DGC pattern with outputs which are physiologically realistic, quantitatively matching experimental results found in this taxonomic model elsewhere. A finite-element mathematical approach is employed and various trigger sets are considered. Parameter sensitivity analyses suggest that various aspects of insect DGC are adequately captured in this model. In particular, with physiologically relevant input parameters, the full DGC pattern is induced; and the phase durations, endotracheal carbon dioxide partial pressure ranges, and pH fluctuations which arise are physically realistic. The model results support the emergent property hypothesis for the existence of DGC, and indicate that asymmetric loading and off-loading (hysteresis) in one of the sensor

  16. Surface effects and discontinuity behavior in nano-systems composed of Prussian blue analogues

    Science.gov (United States)

    Drissi, L. B.; Zriouel, S.; Bahmad, L.

    2018-04-01

    Magnetic properties and hysteresis loops of a nano-ferrimagnetic surface-bulk Prussian blue analogues (PBA) have been studied by means of Monte Carlo simulations. We have reported the effects of the magnetic and the crystal fields, as well as the intermediate and the bulk couplings, the temperature and the size on the phase diagram, the magnetization, the susceptibility, the hysteresis loops, the critical and the discontinuity temperatures of the model. The thermal dependence of the coercivity and the remanent magnetization are also discussed. This study shows a number of characteristic behaviors, such as the discontinuities in the magnetizations, the existence of Q- and N-types behaviors in the Néel classification nomenclature and the occurrence of single and triple hysteresis loops with high number of step-like plateaus. The obtained results make ferrimagnetic surface-bulk PBA useful for technological applications such as thermo-optical recording.

  17. The elusive character of discontinuous deep-water channels: New insights from Lucia Chica channel system, offshore California

    Science.gov (United States)

    Maier, K.L.; Fildani, A.; Paull, C.K.; Graham, S.A.; McHargue, T.R.; Caress, D.W.; McGann, M.

    2011-01-01

    New high-resolution autonomous underwater vehicle (AUV) seafloor images, with 1 m lateral resolution and 0.3 m vertical resolution, reveal unexpected seafloor rugosity and low-relief (architecture of the depositional area. Flowstripped turbidity currents separated into and reactivated multiple channels to create a distributary pattern and developed discontinuous trains of cyclic scours and megaflutes, which may be erosional precursors to continuous channels. The diverse features now imaged in the Lucia Chica channel system (offshore California) are likely common in modern and ancient systems with similar overall morphologies, but have not been previously mapped with lower-resolution detection methods in any of these systems. ?? 2011 Geological Society of America.

  18. Resolution of the Vlasov-Maxwell system by PIC discontinuous Galerkin method on GPU with OpenCL

    Directory of Open Access Journals (Sweden)

    Crestetto Anaïs

    2013-01-01

    Full Text Available We present an implementation of a Vlasov-Maxwell solver for multicore processors. The Vlasov equation describes the evolution of charged particles in an electromagnetic field, solution of the Maxwell equations. The Vlasov equation is solved by a Particle-In-Cell method (PIC, while the Maxwell system is computed by a Discontinuous Galerkin method. We use the OpenCL framework, which allows our code to run on multicore processors or recent Graphic Processing Units (GPU. We present several numerical applications to two-dimensional test cases.

  19. Natural interaction for unmanned systems

    Science.gov (United States)

    Taylor, Glenn; Purman, Ben; Schermerhorn, Paul; Garcia-Sampedro, Guillermo; Lanting, Matt; Quist, Michael; Kawatsu, Chris

    2015-05-01

    Military unmanned systems today are typically controlled by two methods: tele-operation or menu-based, search-andclick interfaces. Both approaches require the operator's constant vigilance: tele-operation requires constant input to drive the vehicle inch by inch; a menu-based interface requires eyes on the screen in order to search through alternatives and select the right menu item. In both cases, operators spend most of their time and attention driving and minding the unmanned systems rather than on being a warfighter. With these approaches, the platform and interface become more of a burden than a benefit. The availability of inexpensive sensor systems in products such as Microsoft Kinect™ or Nintendo Wii™ has resulted in new ways of interacting with computing systems, but new sensors alone are not enough. Developing useful and usable human-system interfaces requires understanding users and interaction in context: not just what new sensors afford in terms of interaction, but how users want to interact with these systems, for what purpose, and how sensors might enable those interactions. Additionally, the system needs to reliably make sense of the user's inputs in context, translate that interpretation into commands for the unmanned system, and give feedback to the user. In this paper, we describe an example natural interface for unmanned systems, called the Smart Interaction Device (SID), which enables natural two-way interaction with unmanned systems including the use of speech, sketch, and gestures. We present a few example applications SID to different types of unmanned systems and different kinds of interactions.

  20. Singularity and dynamics on discontinuous vector fields

    CERN Document Server

    Luo, Albert CJ

    2006-01-01

    This book discussed fundamental problems in dynamics, which extensively exist in engineering, natural and social sciences. The book presented a basic theory for the interactions among many dynamical systems and for a system whose motions are constrained naturally or artificially. The methodology and techniques presented in this book are applicable to discontinuous dynamical systems in physics, engineering and control. In addition, they may provide useful tools to solve non-traditional dynamics in biology, stock market and internet network et al, which cannot be easily solved by the traditional

  1. Modular Adaptive System Based on a Multi-Stage Neural Structure for Recognition of 2D Objects of Discontinuous Production

    Directory of Open Access Journals (Sweden)

    I. Topalova

    2005-03-01

    Full Text Available This is a presentation of a new system for invariant recognition of 2D objects with overlapping classes, that can not be effectively recognized with the traditional methods. The translation, scale and partial rotation invariant contour object description is transformed in a DCT spectrum space. The obtained frequency spectrums are decomposed into frequency bands in order to feed different BPG neural nets (NNs. The NNs are structured in three stages - filtering and full rotation invariance; partial recognition; general classification. The designed multi-stage BPG Neural Structure shows very good accuracy and flexibility when tested with 2D objects used in the discontinuous production. The reached speed and the opportunuty for an easy restructuring and reprogramming of the system makes it suitable for application in different applied systems for real time work.

  2. Organic carbon transport through a discontinuous fluvial system in a Mediterranean catchment after a greening-up process

    Science.gov (United States)

    Boix-Fayos, Carolina; Almagro, María; Díaz-Pereira, Elvira; Pérez-Cutillas, Pedro; de Vente, Joris; Martínez-Mena, María

    2017-04-01

    Quantification of different organic carbon pools mobilized by lateral fluxes is important to close organic carbon (OC) budgets at the catchment scale. This quantification helps to identify in which forms OC is transferred, deposited, and mineralized during the erosion cycle. Many Mediterranean mountain catchments have experienced important land use changes in the last 50 years leading to a recovery of the vegetation in many cases. Furthermore, many of them are characterized by stream discontinuity with high runoff rates responding to intensive hydrological pulses. There is a current lack of knowledge on fluvial OC fluxes and their relation to soil organic carbon stocks in these systems. The objective of this research was to quantify the amount of organic carbon transported by these systems in a catchment representative of Mediterranean conditions and to explore how intermittent fluvial systems can affect organic carbon transported by lateral flows. During six years OC fluvial fluxes in a catchment of 77 km2 in SE Spain were monitored. The catchment experienced a greening-up process in the last 50 years through a conversion mainly from agricultural use (decrease 44%) to forest (increase 45%). Data on water discharge, sediment concentration, total organic carbon (OC) of suspended sediments and dissolved organic carbon (DOC) were collected throughout 32 rainfall events and 13 sampling periods with base flow conditions. The data were collected from two monitoring stations located on two nested subcatchments covering permanent and ephemeral flow conditions. We found no significant differences in OC concentrations in suspended sediments (10.1 ± 5 g kg-1) and DOC (0.014 ± 0.010 g kg-1) between the ephemeral and the permanent streams. However, sediment concentration, index of aggregation and silt content of suspended load were significantly higher in the ephemeral stream than in the permanent one. OC concentration of suspended sediments was much lower than OC

  3. First-order system least-squares for second-order elliptic problems with discontinuous coefficients: Further results

    Energy Technology Data Exchange (ETDEWEB)

    Bloechle, B.; Manteuffel, T.; McCormick, S.; Starke, G.

    1996-12-31

    Many physical phenomena are modeled as scalar second-order elliptic boundary value problems with discontinuous coefficients. The first-order system least-squares (FOSLS) methodology is an alternative to standard mixed finite element methods for such problems. The occurrence of singularities at interface corners and cross-points requires that care be taken when implementing the least-squares finite element method in the FOSLS context. We introduce two methods of handling the challenges resulting from singularities. The first method is based on a weighted least-squares functional and results in non-conforming finite elements. The second method is based on the use of singular basis functions and results in conforming finite elements. We also share numerical results comparing the two approaches.

  4. 78 FR 47822 - Notice of Application for Approval of Discontinuance or Modification of a Railroad Signal System

    Science.gov (United States)

    2013-08-06

    ..., Glendale, NY 11386. LIRR and NYA jointly seek approval of the proposed discontinuance of the automatic..., S72, and S73 will be removed, as well as the pipe-connected center-lock crossover equipment on...

  5. Discontinuous and heterogeneous glass transition behavior of carbohydrate polymer-plasticizer systems.

    Science.gov (United States)

    Kawai, Kiyoshi; Hagura, Yoshio

    2012-07-01

    In order to understand the glass transition properties of carbohydrate polymer-plasticizer systems, glass transition temperatures of dextrin-glucose and dextrin-maltose systems were investigated systematically using differential scanning calorimetry. The onset (Tg(on)) and offset (Tg(off)) of the glass transition decreased with increasing plasticizer (glucose or maltose) content, and showed an abrupt depression at certain plasticizer content. The abrupt depression of Tg(off) occurred at higher plasticizer content than that of Tg(on). The glass transition was much broader for intermediate plasticizer content. From the enthalpy relaxation behavior of samples aged at various temperatures, it was found that two different glass transitions occurred contentiously in the broad glass transition. These results suggested that carbohydrate polymer-plasticizer systems can be classified into three regions: the entrapment of the plasticizer by the polymer, the formations of the polymer-plasticizer and plasticizer-rich domains, and the embedment of polymer into the plasticizer. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. On the stability of rotational discontinuities

    International Nuclear Information System (INIS)

    Richter, P.; Scholer, M.

    1989-01-01

    The stability of symmetric rotational discontinuities in which the magnetic field rotates by 180 degree is investigated by means of a one-dimensional self-consistent hybrid code. Rotational discontinuities with an angle Θ > 45 degree between the discontinuity normal direction and the upstream magnetic field are found to be relatively stable. The discontinuity normal is in the x direction and the initial magnetic field has finite y component only in the transition region. In the case of the ion (left-handed) sense of rotation of the tangential magnetic field, the transition region does not broaden with time. In the case of the electron (right-handed) sense of rotation, a damped wavetrain builds up in the B y component downstream of the rotational discontinuity and the discontinuity broadens with time. Rotational discontinuities with smaller angles, Θ, are unstable. Examples for a rotational discontinuity with Θ = 30 degree and the electron sense of rotation as well as a rotational discontinuity with Θ = 15 degree and the ion sense of rotation show that these discontinuities into waves. These waves travel approximately with Alfven velocity in the upstream direction and are therefore phase standing in the simulation system. The magnetic hodograms of these disintegrated discontinuities are S-shaped. The upstream portion of the hodogram is always right-handed; the downstream portion is always left-handed

  7. Expert Systems - A Natural History

    OpenAIRE

    Shadbolt, N. R.

    1989-01-01

    This paper examines the origins, current state and future prospects for expert systems. The origins are traced from the schism with classic Artificial Intelligence. The characteristics of early expert systems are described and contrasted with more recent developments. A number of influential forces operating on present day systems are reviewed. The future trends in the evolution of expert systems are discussed.

  8. System of Natural Health Products

    Directory of Open Access Journals (Sweden)

    Angelica Paoletti

    2011-01-01

    Full Text Available Introduction. The safety of vitamin K antagonists (VKA use can be compromised by many popular herbal supplements taken by individuals. The literature reports that 30% of warfarin-treated patients self-medicates with herbs. Possible interactions represent an health risk. We aimed to identify all herbs-oral anticoagulants interactions collected in the Italian database of suspected adverse reactions to “natural health” products. Methods. The Italian database of spontaneous reports of suspected adverse reactions to natural products was analyzed to address herb-VKAs interactions. Results. From 2002 to 2009, we identified 12 reports with 7 cases of INR reduction in patients treated with warfarin (n=3 and acenocoumarol (n=4, and 5 cases of INR increase (all warfarin associated. It was reported 8 different herbal products as possibly interacting. Discussion. Our study confirms the risk of interactions, highlighting the difficulty to characterize them and their mechanisms and, finally, prevent their onset. The reported data underline the urgent need of healthcare providers being aware of the possible interaction between natural products and VKA, also because of the critical clinical conditions affecting patients. This is the first step to have the best approach to understand possible INR alterations linked to herb-VKA interaction and to rightly educate patients in treatment with VKA.

  9. 76 FR 17736 - Notice of Application for Approval of Discontinuance or Modification of a Railroad Signal System

    Science.gov (United States)

    2011-03-30

    ... within Yard Limits, between MP 81.00 and MP 83.2, with the discontinuance and removal of automatic signal 821, at Scott St. (MP 82.03), and automatic signal 831 (MP 83.1) near Orleans St. Electric locks will...-operation and an electric lock will be installed. An electric lock is to be installed on the hand-operated...

  10. American Indian Systems for Natural Resource Management.

    Science.gov (United States)

    Quintana, Jorge O.

    1992-01-01

    Outlines the philosophy and general principles of "primitive" indigenous production technologies and natural resource management systems in North and South America. Discusses indigenous practices that promote sustainable production in gathering, hunting and fishing, minerals extraction, and agriculture. (SV)

  11. Engineered containment and control systems: nurturing nature.

    Science.gov (United States)

    Clarke, James H; MacDonell, Margaret M; Smith, Ellen D; Dunn, R Jeffrey; Waugh, W Jody

    2004-06-01

    The development of engineered containment and control systems for contaminated sites must consider the environmental setting of each site. The behaviors of both contaminated materials and engineered systems are affected by environmental conditions that will continue to evolve over time as a result of such natural processes as climate change, ecological succession, pedogenesis, and landform changes. Understanding these processes is crucial to designing, implementing, and maintaining effective systems for sustained health and environmental protection. Traditional engineered systems such as landfill liners and caps are designed to resist natural processes rather than working with them. These systems cannot be expected to provide long-term isolation without continued maintenance. In some cases, full-scale replacement and remediation may be required within 50 years, at an effort and cost much higher than for the original cleanup. Approaches are being developed to define smarter containment and control systems for stewardship sites, considering lessons learned from implementing prescriptive waste disposal regulations enacted since the 1970s. These approaches more effectively involve integrating natural and engineered systems; enhancing sensors and predictive tools for evaluating performance; and incorporating information on failure events, including precursors and consequences, into system design and maintenance. An important feature is using natural analogs to predict environmental conditions and system responses over the long term, to accommodate environmental change in the design process, and, as possible, to engineer containment systems that mimic favorable natural systems. The key emphasis is harmony with the environment, so systems will work with and rely on natural processes rather than resisting them. Implementing these new integrated systems will reduce current requirements for active management, which are resource-intensive and expensive.

  12. Nature-inspired computing for control systems

    CERN Document Server

    2016-01-01

    The book presents recent advances in nature-inspired computing, giving a special emphasis to control systems applications. It reviews different techniques used for simulating physical, chemical, biological or social phenomena at the purpose of designing robust, predictive and adaptive control strategies. The book is a collection of several contributions, covering either more general approaches in control systems, or methodologies for control tuning and adaptive controllers, as well as exciting applications of nature-inspired techniques in robotics. On one side, the book is expected to motivate readers with a background in conventional control systems to try out these powerful techniques inspired by nature. On the other side, the book provides advanced readers with a deeper understanding of the field and a broad spectrum of different methods and techniques. All in all, the book is an outstanding, practice-oriented reference guide to nature-inspired computing addressing graduate students, researchers and practi...

  13. System for the suppression of noise and of noise fluctuations: extraction of a net signal from another one containing frequencies of noise and discontinuous signal

    International Nuclear Information System (INIS)

    Rambaut, M.

    1989-01-01

    A patent is claimed for an invention relating to a system for the suppression of noise and noise fluctuations. The aim of the system is the detection of the signal contained in noise-and-discontinuous signal mixed frequencies. The invention is to be applied in radiation detection. The results of the measurements are reliable for short counting rates, as compared with the time constant of the background noise fluctuations, and for measurements performed in regions having the same background noise average. The diagram, the characteristics and the operation of the invention are described [fr

  14. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS. VII. IMPLICATIONS FROM THE NEARLY UNIVERSAL NATURE OF HORIZONTAL BRANCH DISCONTINUITIES

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T. M.; Bellini, A.; Anderson, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Cassisi, S.; Pietrinferni, A. [INAF-Osservatorio Astronomico di Teramo, Via Mentore Maggini s.n.c., I-64100 Teramo (Italy); D’Antona, F. [INAF-Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monteporzio Catone, Roma (Italy); Salaris, M. [Astrophysics Research Institute,Liverpool John Moores University, Liverpool Science Park, IC2 Building, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Milone, A. P. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT, 2611 (Australia); Dalessandro, E. [Dipartimento di Fisica e Astronomia, Università degli Studi di Bologna, Viale Berti Pichat 6/2, I-40127 Bologna (Italy); Piotto, G.; Ortolani, S.; Nardiello, D. [Dipartimento di Fisica e Astronomia “Galileo Galilei,”Università di Padova, Vicolo dell’Osservatorio 3, I-35122 Padova (Italy); Renzini, A.; Bedin, L. R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Sweigart, A. V. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Sarajedini, A. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Aparicio, A., E-mail: tbrown@stsci.edu, E-mail: jayander@stsci, E-mail: bellini@stsci.edu, E-mail: cassisi@oa-teramo.inaf.it, E-mail: pietrinferni@oa-teramo.inaf.it, E-mail: dantona@oa-roma.inaf.it, E-mail: M.Salaris@ljmu.ac.uk, E-mail: milone@mso.anu.edu.au [Instituto de Astrofísica de Canarias. Calle Vía Láctea s/n. E38200 — La Laguna, Tenerife, Canary Islands (Spain)

    2016-05-01

    The UV-initiative Hubble Space Telescope Treasury survey of Galactic globular clusters provides a new window into the phenomena that shape the morphological features of the horizontal branch (HB). Using this large and homogeneous catalog of UV and blue photometry, we demonstrate that the HB exhibits discontinuities that are remarkably consistent in color (effective temperature). This consistency is apparent even among some of the most massive clusters hosting multiple distinct sub-populations (such as NGC 2808, ω Cen, and NGC 6715), demonstrating that these phenomena are primarily driven by atmospheric physics that is independent of the underlying population properties. However, inconsistencies arise in the metal-rich clusters NGC 6388 and NGC 6441, where the discontinuity within the blue HB (BHB) distribution shifts ∼1000–2000 K hotter. We demonstrate that this shift is likely due to a large helium enhancement in the BHB stars of these clusters, which in turn affects the surface convection and evolution of such stars. Our survey also increases the number of Galactic globular clusters known to host blue-hook stars (also known as late hot flashers) from 6 to 23 clusters. These clusters are biased toward the bright end of the globular cluster luminosity function, confirming that blue-hook stars tend to form in the most massive clusters with significant self-enrichment.

  15. Knowledge Systems and Natural Resources: Management, Policy ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2007-10-31

    Oct 31, 2007 ... In recent years, knowledge systems have become a key area of concern for researchers, policy-makers, and development activists. Knowledge Systems and Natural Resources is a unique collection of case studies from Nepal. It provides rich and incisive insights into critical social processes and ...

  16. Introduction To Natural Resources Management Extension System ...

    African Journals Online (AJOL)

    Introduction To Natural Resources Management Extension System (Nrmes); Rethinking In Extension Systems For 21st Century. ... Growing food demands, soil nutrient depletion is occurring in many tropical and subtropical countries, and land degradation and desertification continues to progress in many other countries.

  17. Natural Resource Information System. Remote Sensing Studies.

    Science.gov (United States)

    Leachtenauer, J.; And Others

    A major design objective of the Natural Resource Information System entailed the use of remote sensing data as an input to the system. Potential applications of remote sensing data were therefore reviewed and available imagery interpreted to provide input to a demonstration data base. A literature review was conducted to determine the types and…

  18. Stability Analysis of Discontinuous Galerkin Approximations to the Elastodynamics Problem

    KAUST Repository

    Antonietti, Paola F.

    2015-11-21

    We consider semi-discrete discontinuous Galerkin approximations of both displacement and displacement-stress formulations of the elastodynamics problem. We prove the stability analysis in the natural energy norm and derive optimal a-priori error estimates. For the displacement-stress formulation, schemes preserving the total energy of the system are introduced and discussed. We verify our theoretical estimates on two and three dimensions test problems.

  19. Two interpretive systems for natural language?

    Science.gov (United States)

    Frazier, Lyn

    2015-02-01

    It is proposed that humans have available to them two systems for interpreting natural language. One system is familiar from formal semantics. It is a type based system that pairs a syntactic form with its interpretation using grammatical rules of composition. This system delivers both plausible and implausible meanings. The other proposed system is one that uses the grammar together with knowledge of how the human production system works. It is token based and only delivers plausible meanings, including meanings based on a repaired input when the input might have been produced as a speech error.

  20. Natural systems prediction of radionuclide migration

    International Nuclear Information System (INIS)

    Ewing, R.C.

    1991-01-01

    This paper reviews the application (and limitations) of data from natural systems to the verification of performance assessments, particularly as they apply to the evaluation of the long-term performance of waste forms, backfill, canister materials, and finally, the integrity of the repository itself. Two specific examples, the corrosion of borosilicate glass and the formation of alteration products of spent fuel, will be discussed. In both cases, inferences are of three types: 1) directly applicable data (i.e. radiation effects, stable phase assemblages): 2) inferences based on the analogous behaviour of the natural and repository systems (e.g. long-term corrosion rate); 3) specific identification of new phenomena that could not have been anticipated from the short term laboratory data (i.e. new mechanisms for the retention or release of radionuclides). The latter can only be derived from the observation of natural systems. Finally, specific attention will be paid to the limitations in the use of natural systems, particularly as the spatial and temporal scales expand, and to the inherent limitations of prediction and verification. (J.P.N.)

  1. Neural networks with discontinuous/impact activations

    CERN Document Server

    Akhmet, Marat

    2014-01-01

    This book presents as its main subject new models in mathematical neuroscience. A wide range of neural networks models with discontinuities are discussed, including impulsive differential equations, differential equations with piecewise constant arguments, and models of mixed type. These models involve discontinuities, which are natural because huge velocities and short distances are usually observed in devices modeling the networks. A discussion of the models, appropriate for the proposed applications, is also provided. This book also: Explores questions related to the biological underpinning for models of neural networks\\ Considers neural networks modeling using differential equations with impulsive and piecewise constant argument discontinuities Provides all necessary mathematical basics for application to the theory of neural networks Neural Networks with Discontinuous/Impact Activations is an ideal book for researchers and professionals in the field of engineering mathematics that have an interest in app...

  2. The Nature of Stability in Replicating Systems

    Directory of Open Access Journals (Sweden)

    Addy Pross

    2011-02-01

    Full Text Available We review the concept of dynamic kinetic stability, a type of stability associated specifically with replicating entities, and show how it differs from the well-known and established (static kinetic and thermodynamic stabilities associated with regular chemical systems. In the process we demonstrate how the concept can help bridge the conceptual chasm that continues to separate the physical and biological sciences by relating the nature of stability in the animate and inanimate worlds, and by providing additional insights into the physicochemical nature of abiogenesis.

  3. Scaling view by the Virtual Nature Systems

    Science.gov (United States)

    Klenov, Valeriy

    2010-05-01

    The Actual Nature Systems (ANS) continually are under spatial-temporal governing external influences from other systems (Meteorology and Geophysics). This influences provide own spatial temporal patterns on the Earth Nature Systems, which reforms these influences by own manner and scales. These at last three systems belong to the Open Non Equilibrium Nature Systems (ONES). The Geophysics and Meteorology Systems are both governing for the ANS on the Earth. They provide as continual energetic pressure and impacts, and direct Extremes from the both systems to the ANS on Earth surface (earthquakes, storms, and others). The Geodynamics of the ANS is under mixing of influence for both systems, on their scales and on dynamics of their spatial-temporal structures, and by own ANS properties, as the ONES. To select influences of external systems on the Earth systems always is among major tasks of the Geomorphology. Mixing of the Systems scales and dynamics provide specific properties for the memory of Earth system. The memory of the ANS has practical value for their multi-purpose management. The knowledge of these properties is the key for research spatial-temporal GeoDynamics and Trends of Earth Nature Systems. Selection of the influences in time and space requires for special tool, requires elaboration and action of the Virtual Nature Systems (VNS), which are enliven computer doubles for analysis Geodynamics of the ANS. The Experience on the VNS enables to assess influence of each and both external factors on the ANS. It is source of knowledge for regional tectonic and climate oscillations, trends, and threats. Research by the VNS for spatial-temporal dynamics and structures of stochastic regimes of governing systems and processes results in stochastic GeoDynamics of environmental processes, in forming of false trends and blanks in natural records. This ‘wild dance' of 2D stochastic patterns and their interaction each other and generates acting structures of river nets

  4. Studies of natural analogues and geological systems

    International Nuclear Information System (INIS)

    Brandberg, F.; Grundfelt, B.; Hoeglund, L.; Skagius K.; Karlsson, F.; Smellie, J.

    1993-04-01

    This review has involved studies of natural analogues and natural geological systems leading to the identification and quantification of processes and features of importance to the performance and safety of repositories for radioactive waste. The features and processes selected for the study comprise general geochemical issues related to the performance of the near- and far-field, the performance and durability of construction materials and the effects of glaciation. For each of these areas a number of potentially important processes for repository performance have been described, and evidence for their existence, as well as quantification of parameters of models describing the processes have been sought from major natural analogue studies and site investigations. The review has aimed at covering a relatively broad range of issues at the expense of in-depth analysis. The quantitative data presented are in most cases compilations of data from the literature; in a few cases results of evaluations made within the current project are included

  5. Knowledge Systems and Natural Resources : Management, Policy ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    31 oct. 2007 ... Knowledge Systems and Natural Resources est un recueil unique d'études de cas réalisées au Népal. Cet ouvrage apporte un éclairage ... Un débat d'experts organisé par le CRDI s'attaque au mariage précoce lors du forum sur la condition des femmes à l'ONU. Des chercheurs appuyés par le CRDI ...

  6. Arabic Natural Language Processing System Code Library

    Science.gov (United States)

    2014-06-01

    POS Tagging, and Dependency Parsing. Fourth Workshop on Statistical Parsing of Morphologically Rich Languages (SPMRL). English (Note: These are for...Detection, Affix Labeling, POS Tagging, and Dependency Parsing" by Stephen Tratz presented at the Statistical Parsing of Morphologically Rich Languages ...and also English ) natural language processing (NLP), containing code for training and applying the Arabic NLP system described in Stephen Tratz’s

  7. Free discontinuity problems

    CERN Document Server

    Pratelli, Aldo

    2016-01-01

    This book presents a series of lectures on three of the best known examples of free discontinuity problems: the Mumford-Shah model for image segmentation, a variational model for the epitaxial growth of thin films, and the sharp interface limit of the Ohta-Kawasaki model for pattern formation in dyblock copolymers.

  8. Natural oscillation frequencies for arbitrary piping systems

    International Nuclear Information System (INIS)

    Gale, J.; Tiselj, I.

    2007-01-01

    This paper concerns axial and lateral oscillations and oscillation frequencies of various empty (natural frequency of oscillation) and fluid filled (forced oscillation) piping systems. Forced oscillations of fluid filled piping systems and corresponding exchange of energy are denominated also Fluid-Structure-Interaction (FSI). Oscillations appear due to various external or internal impacts and are successfully described with eight-equation physical model for simulations of FSI during fast transients. The physical model is solved with characteristic upwind numerical method and is compiled into a computer code. Simulations were compared to the analytical solutions or solutions from the literature whenever was possible. Discussion on results and problems encountered is given. The proposed physical model gives accurate results, and it enables evaluation of natural frequency of arbitrarily loaded, arbitrarily shaped and arbitrarily supported piping systems. Piping systems are rarely empty, thus forced oscillations due to FSI effects were observed and simulated. Application of various fluids pointed out importance of the fluid's compressibility on pipe's axial oscillations. (author)

  9. Receiver Function Imaging of Mantle Transition Zone Discontinuities Beneath the Tanzania Craton and Adjacent Segments of the East African Rift System

    Science.gov (United States)

    Sun, Muchen; Liu, Kelly H.; Fu, Xiaofei; Gao, Stephen S.

    2017-12-01

    The mantle transition zone (MTZ) discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System are imaged by stacking over 7,100 receiver functions. The mean thickness of the MTZ beneath the Western Branch and Tanzania Craton is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an up to 30 km thinning of the MTZ is observed and is attributable to upwelling of higher temperature materials from either the upper MTZ or the lower mantle. The observations are in agreement with the hypothesis that rifting in Africa is primarily driven by gradients of gravitational potential energy and lateral variations of basal traction force along zones of significant changes of lithospheric thickness such as the edges of the Tanzania Craton.

  10. Reliability evaluation of a natural circulation system

    International Nuclear Information System (INIS)

    Jafari, Jalil; D'Auria, Francesco; Kazeminejad, Hossein; Davilu, Hadi

    2003-01-01

    This paper discusses a reliability study performed with reference to a passive thermohydraulic natural circulation (NC) system, named TTL-1. A methodology based on probabilistic techniques has been applied with the main purpose to optimize the system design. The obtained results have been adopted to estimate the thermal-hydraulic reliability (TH-R) of the same system. A total of 29 relevant parameters (including nominal values and plausible ranges of variations) affecting the design and the NC performance of the TTL-1 loop are identified and a probability of occurrence is assigned for each value based on expert judgment. Following procedures established for the uncertainty evaluation of thermal-hydraulic system codes results, 137 system configurations have been selected and each configuration has been analyzed via the Relap5 best-estimate code. The reference system configuration and the failure criteria derived from the 'mission' of the passive system are adopted for the evaluation of the system TH-R. Four different definitions of a less-than-unity 'reliability-values' (where unity represents the maximum achievable reliability) are proposed for the performance of the selected passive system. This is normally considered fully reliable, i.e. reliability-value equal one, in typical Probabilistic Safety Assessment (PSA) applications in nuclear reactor safety. The two 'point' TH-R values for the considered NC system were found equal to 0.70 and 0.85, i.e. values comparable with the reliability of a pump installed in an 'equivalent' forced circulation (active) system having the same 'mission'. The design optimization study was completed by a regression analysis addressing the output of the 137 calculations: heat losses, undetected leakage, loop length, riser diameter, and equivalent diameter of the test section have been found as the most important parameters bringing to the optimal system design and affecting the TH-R. As added values for this work, the comparison has

  11. IS DISCONTINUOUS BERGSONISM POSSIBLE?

    Directory of Open Access Journals (Sweden)

    TERESA CASTELÃO-LAWLESS

    2010-11-01

    Full Text Available Gaston Bachelard’s position toward the philosophy of Henri Bergson is most interesting. In La Dialectique de la durée (1936, Bachelard claims that “of Bergsonism we accept everything but continuity” and that the rest of his book will be an attempt to show the possibility of a “discontinuous Bergsonism”. In this paper, I focus on the reaction of Bachelard to works of Bergson such as the Essai sur les données immédiates de la conscience (1889, L’Evolution créatrice (1907, and Durée et simultanéité: à propos de la théorie d’Einstein (1922 and demonstrate that even though the conditions necessary for the possibility of a discontinuous Bergsonism are not the same ones which Bachelard had in mind when he accepted most of Bergsonism, their phenomenologies of the scientific spirit were analogous.

  12. Receiver function imaging of mantle transition zone discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System

    Science.gov (United States)

    Sun, M.; Liu, K. H.; Fu, X.; Gao, S. S.

    2017-12-01

    To investigate the mechanism of initiation and development of the Eastern African Rifting System (EARS) circumfluent the Tanzania Craton (TC), over 7,100 P-to-S radial receiver functions (RFs) recorded by 87 broadband seismic stations are stacked to map the topography of mantle transition zone (MTZ) discontinuities beneath the TC and the Eastern and Western Branches of the EARS. After time-depth conversion using the 1-D IASP91 Earth model, the resulting 410 km (d410) and 660 km (d660) discontinuity apparent depths are found to be greater than the global averages beneath the whole study area, implying slower than normal upper mantle velocities. The mean thickness of the MTZ beneath the Western Branch and TC is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an 30 km thinning of the MTZ is observed from an up to 50 km and 20 km apparent depression of the d410 and d660, respectively. On the basis of previous seismic tomographic results and empirical relationships between velocity and thermal anomalies, we propose that the most plausible explanation for the observations beneath the volcanic Eastern Branch is the existence of a low-velocity layer extending from the surface to the upper MTZ, probably caused by decompression partial melting associated with continental rifting. The observations are in general agreement with an upper mantle origin for the initiation and development of both the Western and Eastern Branches of the EARS beneath the study area.

  13. Scaling view by the Virtual Nature Systems

    Science.gov (United States)

    Klenov, Valeriy

    2010-05-01

    The Virtual Nature System is irreplaceable for research and evaluation for governing processes on the Earth. Processes on the Earth depends on external exogenous and endogenous influences, and on own dynamics of the Actual Nature Systems (ANS). To select part of the actors is impossible without take in account factor of the Time, factor for information safety during the Time. The stochastic nature of external influences and stochastic pattern for dynamics of Nature systems complicates evaluation of 2D threat of disasters. These are multi-layer, multi-scale, and multi-driven structures of surface processes. Their spatial-temporal overlapping of them generates relatively stable structure of river basins and of river net. Dynamics of processes in river basins results in remove of the former sediments and levels, and in displace of erosion/sedimentation pattern, in destroy and dissipation for a memory the ANS. This complex process results in the Information Loss Law (ILL) in the ANS, which gradually cut off own Past. This view on the GeoDynamics appeared after long time field measurements thousands of terrace levels, hundreds of terrace ranks, and terrace complexes in river basins (Klenov, 1986, 2004). Action of the ILL leads to blanks in natural records, which are non-linearly increasing to the Past, and in appearance of false trends in the records. This temporal barrier prevents evaluation of the history. The way to view spatial-temporal dynamics of the ANS is creation for the portrait Virtual Nature Systems, as acting doubles of the actual nature systems (ANS). Exogenous and endogenous influences are governing drivers of the ANS and of corresponding VNS. The VNS is necessary for research of spatial-temporal GeoDynamics. Unfortunately, the ILL is working not only for the Past, but also restrict ‘view' the Future. It is because of future drivers are yet unknown with necessary exactness, and due high sensitivity of nature systems to external pressure. However, a time

  14. Naturalness, value systems and perception of risk

    International Nuclear Information System (INIS)

    Drottz Sjoberg, B.M.

    1998-01-01

    Full text of publication follows: what is natural? And what is Nature? Are perceptions of Nature and naturalness related to perceptions of risk? This paper focuses on these aspects based on results from a Swedish representative sample (N=731), where subjects indicated e.g. the degree of naturalness of various phenomena, their views of nature, and personal life values, as well as perceptions of risk in specified contexts. The results showed a tendency to perceive as natural the phenomenon which is positively valued, i.e. what is natural is also good or desirable. Further, there were weak correlations between perceived naturalness and indicators of technological optimism, possibly indicating that persons with a more generous view of what is natural also more easily might accept change and outcomes due to human intelligence and activity. The construct of 'tampering with nature' has previously been shown to be one good predictor of perceived risk. The respondents also rated their agreement with items aimed to reflect the four 'views of nature' as suggested by Cultural Theory, i.e. nature as robust, capricious, tolerant and fragile. Nature was foremost perceived as fragile, but the main result clearly revealed that peoples' views of nature were complex and most often involved several of the suggested categories. The discussion focuses on the possible implications on environmental concern and risk perception given that Nature would develop into an undesirable type of locality. (author)

  15. Discontinuous Galerkin Method for Hyperbolic Conservation Laws

    KAUST Repository

    Mousikou, Ioanna

    2016-11-11

    Hyperbolic conservation laws form a special class of partial differential equations. They describe phenomena that involve conserved quantities and their solutions show discontinuities which reflect the formation of shock waves. We consider one-dimensional systems of hyperbolic conservation laws and produce approximations using finite difference, finite volume and finite element methods. Due to stability issues of classical finite element methods for hyperbolic conservation laws, we study the discontinuous Galerkin method, which was recently introduced. The method involves completely discontinuous basis functions across each element and it can be considered as a combination of finite volume and finite element methods. We illustrate the implementation of discontinuous Galerkin method using Legendre polynomials, in case of scalar equations and in case of quasi-linear systems, and we review important theoretical results about stability and convergence of the method. The applications of finite volume and discontinuous Galerkin methods to linear and non-linear scalar equations, as well as to the system of elastodynamics, are exhibited.

  16. Confinement properties evolution of the cap-rocks argillite-type under CO2 enriched-fluids: impact of the natural and artificial discontinuities

    International Nuclear Information System (INIS)

    Berthe, G.

    2012-01-01

    This research is part of the studies of feasibility of CO 2 storage in deep geological strata, focusing more particularly on the evolution of the confinement properties of cap-rocks type argillite subjected to CO 2 enriched fluids. The argillite of Tournemire (Aveyron, France) were used as analog rocks, having identified what their weak points could be face to storage, namely their mineralogy, natural fractures filled with calcite and the presence of interfaces cement/argillite expected in filled injection wells. The 'through diffusion' experimental setup has been adapted to estimate (i) the possible modification of diffusive transport parameters recorded before and after acid attack for different radioactive tracers (tritium and chlorine-36) and non-radioactive tracers (deuterium and bromide) used to characterize samples of argillite of Tournemire and cement paste and (ii) the evolution of the chemical compositions of the solutions in the upstream and downstream reservoirs of diffusion cells during acid attacks. Finally, the analysis of solids was carried out in part by SEM-EDS, XRD and X-μTomography. Firstly, for all the samples studied, the values of the transport parameters determined before acid attack (effective diffusion coefficient and porosity) are consistent with those of the literature. In addition, it appears that all materials have reacted strongly to acid attacks. Thus, argillites saw their diffusion parameters increase up to a factor of two, especially for anionic tracers, and, whatever the proportion of carbonate minerals initially present in samples of argillite. The post-mortem observations have led to the identification of a zone of dissolution of carbonate minerals in them, but whose extension (400 microns or less) can not alone explain the significant degradation of the containment properties. Only unobservable phenomena during investigation scale, such as wormhole effects in porous network could be the cause. In addition, the samples of

  17. Are Human and Natural Systems Decoupling?

    Science.gov (United States)

    Ehrlich, P. R.; Ehrlich, A. H.

    2012-12-01

    Typically, studies of coupled human and natural systems focus on reciprocating interactions and feedbacks between social systems and their biophysical environments. A major challenge today for CHANS scholars is to determine whether significant coupling remains or whether society is simply plunging ahead without reacting effectively to the deterioration of the environment. Thresholds for serious climate disruption are passing, toxification of Earth is proceeding apace and producing worrying symptoms, losses of vital biodiversity are at a 65 million-year high with serious consequences for ecosystem services, the epidemiological environment is deteriorating and a race is building to control water flows and extract the last high-quality resources, increasing the chances of ending civilization in an environment-wrecking nuclear war. The social system has attempted to respond to this perfect storm of problems. In the 1960s, building on much earlier work, scientists began assessing the consequences of an ever-growing human population and expanding consumption, overuse of pesticides, radioactive fallout, air and water pollution, and other environmental issues - and to recommend ameliorative steps. In the mid-1980s, biologists formed the discipline of conservation biology with the explicit purpose of stemming the hemorrhage of biodiversity. In the late 1980s, perhaps the single most important reaction to the worsening environmental situation was the development of the Montreal Protocol to preserve the vital stratospheric ozone layer. Around the same time, it dawned on the scientific community that climate disruption was going to be more immediate and dangerous than previously thought, but attempts by the world community to take mitigating steps have been pathetic. Action to deal with other dimensions of the environmental dilemma has been utterly inadequate. To see the growing disconnect, one only has to consider the attention paid in public discourse to the relatively

  18. 33 CFR 183.620 - Natural ventilation system.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Natural ventilation system. 183... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.620 Natural ventilation system. (a) Except for compartments open to the atmosphere, a natural ventilation system that meets the...

  19. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System

    Directory of Open Access Journals (Sweden)

    Gianluigi de Gennaro

    2015-12-01

    Full Text Available Around 50% of the world’s population, particularly in developing countries, uses biomass as one of the most common fuels. Biomass combustion releases a considerable amount of various incomplete combustion products, including particulate matter (PM and polycyclic aromatic hydrocarbons (PAHs. The paper presents the results of Indoor Air Quality (IAQ measurements in six houses equipped with wood burning stoves or fireplaces as heating systems. The houses were monitored for 48-h periods in order to collect PM10 samples and measure PAH concentrations. The average, the maximum and the lowest values of the 12-h PM10 concentration were 68.6 μg/m3, 350.7 μg/m3 and 16.8 μg/m3 respectively. The average benzo[a]pyrene 12-h concentration was 9.4 ng/m3, while the maximum and the minimum values were 24.0 ng/m3 and 1.5 ng/m3, respectively. Continuous monitoring of PM10, PAHs, Ultra Fine Particle (UFP and Total Volatile Organic Compounds (TVOC was performed in order to study the progress of pollution phenomena due to biomass burning, their trends and contributions to IAQ. The results show a great heterogeneity of impacts on IAQ in terms of magnitude and behavior of the considered pollutants’ concentrations. This variability is determined by not only different combustion technologies or biomass quality, but overall by different ignition mode, feeding and flame management, which can also be different for the same house. Moreover, room dimensions and ventilation were significant factors for pollution dispersion. The increase of PM10, UFP and PAH concentrations, during lighting, was always detected and relevant. Continuous monitoring allowed singling out contributions of other domestic sources of considered pollutants such as cooking and cigarettes. Cooking contribution produced an impact on IAQ in same cases higher than that of the biomass heating system.

  20. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System.

    Science.gov (United States)

    de Gennaro, Gianluigi; Dambruoso, Paolo Rosario; Di Gilio, Alessia; Di Palma, Valerio; Marzocca, Annalisa; Tutino, Maria

    2015-12-24

    Around 50% of the world's population, particularly in developing countries, uses biomass as one of the most common fuels. Biomass combustion releases a considerable amount of various incomplete combustion products, including particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs). The paper presents the results of Indoor Air Quality (IAQ) measurements in six houses equipped with wood burning stoves or fireplaces as heating systems. The houses were monitored for 48-h periods in order to collect PM10 samples and measure PAH concentrations. The average, the maximum and the lowest values of the 12-h PM10 concentration were 68.6 μg/m³, 350.7 μg/m³ and 16.8 μg/m³ respectively. The average benzo[a]pyrene 12-h concentration was 9.4 ng/m³, while the maximum and the minimum values were 24.0 ng/m³ and 1.5 ng/m³, respectively. Continuous monitoring of PM10, PAHs, Ultra Fine Particle (UFP) and Total Volatile Organic Compounds (TVOC) was performed in order to study the progress of pollution phenomena due to biomass burning, their trends and contributions to IAQ. The results show a great heterogeneity of impacts on IAQ in terms of magnitude and behavior of the considered pollutants' concentrations. This variability is determined by not only different combustion technologies or biomass quality, but overall by different ignition mode, feeding and flame management, which can also be different for the same house. Moreover, room dimensions and ventilation were significant factors for pollution dispersion. The increase of PM10, UFP and PAH concentrations, during lighting, was always detected and relevant. Continuous monitoring allowed singling out contributions of other domestic sources of considered pollutants such as cooking and cigarettes. Cooking contribution produced an impact on IAQ in same cases higher than that of the biomass heating system.

  1. Discontinuous jamming transitions in soft materials: coexistence of flowing and jammed states

    International Nuclear Information System (INIS)

    Dennin, Michael

    2008-01-01

    Many systems in nature exhibit transitions between fluid-like states and solid-like states, or 'jamming transitions'. There is a strong theoretical foundation for understanding equilibrium phase transitions that involve solidification, or jamming. Other jamming transitions, such as the glass transition, are less well understood. The jamming phase diagram has been proposed to unify the description of equilibrium phase transitions, the glass transitions, and other nonequilibrium jamming transitions. As with equilibrium phase transitions, which can either be first order (discontinuous in a relevant order parameter) or second order (continuous), one would expect that generalized jamming transitions can be continuous or discontinuous. In studies of flow in complex fluids, there is a wide range of evidence for discontinuous transitions, mostly in the context of shear localization, or shear banding. In this paper, I review the experimental evidence for discontinuous transitions. I focus on systems in which there is a discontinuity in the rate of strain between two, coexisting states: one in which the material is flowing and the other in which it is solid-like. (topical review)

  2. Desicion Support System For Natural Hazards

    Science.gov (United States)

    Vyazilov, E.

    2009-04-01

    recommendations should be reasonable. To resolve the above problems or to make them less significant it is necessary to develop decision support systems (DSS). DMs need not tables with initial data, analytical, forecasting and climatic information, but messages containing warnings on critical value accidence, information on probability of hazards, information on potential losses, and information on hazardous impacts and recommendations on decision making. DSS can do the following: take into account impacts on specific points and on the total area under consideration; allow for the effects of the environment on economic entities (objects) in any geographical region to be analyzed; distinguish impacts and changes caused both by different phenomena and by their combination; signal when objects are or can be in adverse environmental conditions, e.g. in the area affected by fog, storm, tropical cyclone or in the area where the probability of hazardous ice events is very high, etc. The main component of DSS is a knowledge base based on the following concept: if we know environmental conditions it is possible to predict potential impacts on the economy; if we know impacts it is possible to give a set of recommendations on how to prevent (reduce) losses or how to use natural resources most efficiently. Decision making criteria are safety of people and property, reduction of losses, increase of profit, materials saving, etc. Knowledge base is a set of rules formulated in a formalized way using if, that, else. If "Water level in S.-Petersburg >150 cm" that "To give out warning information "Hazards for building on coastal river Neva is possible" and recommendations "The valuable goods carry out in second floor" else "To switch another rule". To have a knowledge base in place it is necessary to: develop tools of identifying and getting knowledge from experts; arrange the information flow from available information systems (operational data, analyses, forecasts, climatic information) through

  3. Gas exchange measurements in natural systems

    International Nuclear Information System (INIS)

    Broecker, W.S.; Peng, T.H.

    1983-01-01

    Direct knowledge of the rates of gas exchange in lakes and the ocean is based almost entirely on measurements of the isotopes 14 C, 222 Rn and 3 He. The distribution of natural radiocarbon has yielded the average rate of CO 2 exchange for the ocean and for several closed basin lakes. That of bomb produced radiocarbon has been used in the same systems. The 222 Rn to 226 Ra ratio in open ocean surface water has been used to give local short term gas exchange rates. The radon method generally cannot be used in lakes, rivers, estuaries or shelf areas because of the input of radon from sediments. A few attempts have been made to use the excess 3 He produced by decay of bomb produced tritium in lakes to give gas transfer rates. The uncertainty in the molecular diffusivity of helium and in the diffusivity dependence of the rate of gas transfer holds back the application of this method. A few attempts have been made to enrich the surface waters of small lakes with 226 Ra and 3 H in order to allow the use of the 222 Rn and 3 He methods. While these studies give broadly concordant results, many questions remain unanswered. The wind velocity dependence of gas exchange rate has yet to be established in field studies. The dependence of gas exchange rate on molecular diffusivity also remains in limbo. Finally, the degree of enhancement of CO 2 exchange through chemical reactions has been only partially explored. 49 references, 2 figures, 2 tables

  4. Intrauterine Contraceptive Device Discontinuation Among Women in ...

    African Journals Online (AJOL)

    In conclusion, more effort should be directed to counseling for adherence to the IUD use to ensure longer duration of use. Provision of the levonorgestrel intrauterine system which reduces bleeding and dysmenorrhoea, in our clinic may increase the continuation rate of IUD. Key words; IUD, duration of use, discontinuation, ...

  5. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    Administrator

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the ... force, the fundamental problem for the driving force for grain boundary (GB) migration, exists. .... systems (Germany: Springer Verlag). Kashyap K T, Ramachandra C, Sujatha M and ...

  6. Discontinuity formulas for multiparticle amplitudes

    International Nuclear Information System (INIS)

    Stapp, H.P.

    1976-03-01

    It is shown how discontinuity formulas for multiparticle scattering amplitudes are derived from unitarity and analyticity. The assumed analyticity property is the normal analytic structure, which was shown to be equivalent to the space-time macrocausality condition. The discontinuity formulas to be derived are the basis of multi-particle fixed-t dispersion relations

  7. Testing discontinuities in nonparametric regression

    KAUST Repository

    Dai, Wenlin

    2017-01-19

    In nonparametric regression, it is often needed to detect whether there are jump discontinuities in the mean function. In this paper, we revisit the difference-based method in [13 H.-G. Müller and U. Stadtmüller, Discontinuous versus smooth regression, Ann. Stat. 27 (1999), pp. 299–337. doi: 10.1214/aos/1018031100

  8. Note on the natural system of units

    Indian Academy of Sciences (India)

    express L, M and T and therefore all other physical magnitudes in terms of the primary ones. In this Note we take stand with the conventional choice of natural units, making a single change for GN (Newton's constant) so as to avoid the square roots in expressing length, mass and time. We analyse the new proposal in the ...

  9. Inter-Firm Co-Operative Strategies In The Context Of Discontinuous Technological Change. The Case Of The Uk Optical Communications Systems Industry

    NARCIS (Netherlands)

    S. Spedale-Latimer (Simona)

    2002-01-01

    textabstractAt times of discontinuous technological change co-operation represents a viable strategy for both incumbents and new-entrants, provided that the choice of co-operation is consistent with the firm's business strategy (market-pull vs. technology-push) and with its degree of organizational

  10. Are there martial art styles that represent natural systems?

    Directory of Open Access Journals (Sweden)

    Joachim T. Haug

    2015-12-01

    Full Text Available For didactics, systematically structured teaching contents are desirable, and natural systems would be most comprehensible. We tested whether serrada-escrima styles (SES, a type of Filipino martial arts, represent a natural system. Natural systems are considered to have an inner coherence. This means that based on some elements of the system the other elements can be predicted, based on knowledge of the characteristics of the elements of the system. SES is a good candidate to test this hypothesis, as it embraces only a relatively small set of techniques. It appears that SES indeed represents a natural, coherent system with 12 elements that can be grouped into three also coherent sets, each with four techniques. One basic pre-assumption is necessary to make SES a natural system; this pre-assumption is derived from knowledge of medieval European sword fighting, more precisely Messerfechten. We furthermore discuss indications for the historic background of SES.

  11. Method and system for natural gas utilization

    International Nuclear Information System (INIS)

    Halmoe, T.M.

    1995-01-01

    The invention relates to an method on reducing the emission of carbon oxides during methanol production. (a) A first part of the natural feeding gas is to be converted to synthesis gas consisting of CO, H 2 , CO 2 , H 2 O and non-converted natural gas. (b) A second part of the natural feeding gas is to be combusted for the generation of heat used in the conversion process by means of which the volumes of CO 2 and H 2 O are formed. (c) The synthesis gas from (a) is to be converted to a product gas flow consisting of methanol and non-converted synthesis gas. (d) The product gas flow from (c) is to be cooled, and methanol is to be separated. (e) A first part of the non-converted gas from the separation step (d) is to be combined with the synthesis gas from (a). (f) A second part of the non-converted gas from the separation step (d) together with CO 2 and H 2 O from step (b) is to be led to a shift reactor for making the equilibrium of CO, H 2 , CO, and H 2 O. (g) CO from step (f) is to be converted with methanol from step (d) for production of acetic acid. 1 fig

  12. Human Nature and its Implications for the Legal System | Obioha ...

    African Journals Online (AJOL)

    This paper examines the implications the various conceptions of human nature hold for the legal system. No doubt, there are various and conflicting theories of human nature such that the concept of human nature seems to have remained elusive and pervasive. Some conceive man as nothing but matter pure and simple; ...

  13. SERVING TIMES OF DISCONTINUOUS MATERIALS HANDLING MACHINES

    OpenAIRE

    PÉTER TELEK

    2014-01-01

    The performance of production systems highly depend on the effectiveness of the serving process, which consist of different materials handling operations depend on the applied machines. During the design process of serving systems there are key role of the characterisations of the handling equipment: they determine the applicability of the given machines. In my paper, I analyse the serving operations of discontinuous materials handling machines and define the time requirements of them. After ...

  14. Visualization and natural control systems for microscopy

    DEFF Research Database (Denmark)

    Taylor, Russell M.; Borland, David; Brooks, Frederick P.

    2005-01-01

    This chapter presents these microscope systems, along with brief descriptions of the science experiments driving the development of each system. Beginning with a discussion of the philosophy that has driven the Nanoscale Science Research Group (NSRG) and the methods used, the chapter describes th...

  15. Natural disasters and the gas pipeline system.

    Science.gov (United States)

    1996-11-01

    Episodic descriptions are provided of the effects of the Loma Prieta earthquake (1989) on the gas pipeline systems of Pacific Gas & Electric Company and the Cit of Palo Alto and of the Northridge earthquake (1994) on Southern California Gas' pipeline...

  16. Fractal Modeling and Scaling in Natural Systems - Editorial

    Science.gov (United States)

    The special issue of Ecological complexity journal on Fractal Modeling and Scaling in Natural Systems contains representative examples of the status and evolution of data-driven research into fractals and scaling in complex natural systems. The editorial discusses contributions to understanding rela...

  17. Thermal analysis of a kitchen natural ventilation system with ...

    African Journals Online (AJOL)

    A numerical study was conducted to perform the design analysis of a novel kitchen natural ventilation system of Madirelo Hotel School. The analysis was performed by using Computational Fluid Dynamics to assess the performance of natural ventilation system. The design is expected to be energy efficient and cost effective ...

  18. LNG systems for natural gas propelled ships

    Science.gov (United States)

    Chorowski, M.; Duda, P.; Polinski, J.; Skrzypacz, J.

    2015-12-01

    In order to reduce the atmospheric pollution generated by ships, the International Marine Organization has established Emission Controlled Areas. In these areas, nitrogen oxides, sulphur oxides and particulates emission is strongly controlled. From the beginning of 2015, the ECA covers waters 200 nautical miles from the coast of the US and Canada, the US Caribbean Sea area, the Baltic Sea, the North Sea and the English Channel. From the beginning of 2020, strong emission restrictions will also be in force outside the ECA. This requires newly constructed ships to be either equipped with exhaust gas cleaning devices or propelled with emission free fuels. In comparison to low sulphur Marine Diesel and Marine Gas Oil, LNG is a competitive fuel, both from a technical and economical point of view. LNG can be stored in vacuum insulated tanks fulfilling the difficult requirements of marine regulations. LNG must be vaporized and pressurized to the pressure which is compatible with the engine requirements (usually a few bar). The boil-off must be controlled to avoid the occasional gas release to the atmosphere. This paper presents an LNG system designed and commissioned for a Baltic Sea ferry. The specific technical features and exploitation parameters of the system will be presented. The impact of strict marine regulations on the system's thermo-mechanical construction and its performance will be discussed. The review of possible flow-schemes of LNG marine systems will be presented with respect to the system's cost, maintenance, and reliability.

  19. Future systems for living with nature

    Directory of Open Access Journals (Sweden)

    Vesna Petrešin

    2000-01-01

    Full Text Available The architect Jan Kaplicky reached the recognition of his Future Systems and their visionary architectural, design and urban concepts only within the past decade. Their aesthetics, inspired by the latest air- and space technology and materials, has influenced the architectural form of the late 20th century. Future Systems have been dealing with dwelling in various media (earth, air, water, space and developing ideas about reshaping the city centres through their radical urbanism. The numerous flexible and mobile designs have proved to be astonishingly advanced through their ecologic and economic efficiency.

  20. Natural history of eukaryotic DNA methylation systems.

    Science.gov (United States)

    Iyer, Lakshminarayan M; Abhiman, Saraswathi; Aravind, L

    2011-01-01

    Methylation of cytosines and adenines in DNA is a widespread epigenetic mark in both prokaryotes and eukaryotes. In eukaryotes, it has a profound influence on chromatin structure and dynamics. Recent advances in genomics and biochemistry have considerably elucidated the functions and provenance of these DNA modifications. DNA methylases appear to have emerged first in bacterial restriction-modification (R-M) systems from ancient RNA-modifying enzymes, in transitions that involved acquisition of novel catalytic residues and DNA-recognition features. DNA adenine methylases appear to have been acquired by ciliates, heterolobosean amoeboflagellates, and certain chlorophyte algae. Six distinct clades of cytosine methylases, including the DNMT1, DNMT2, and DNMT3 clades, were acquired by eukaryotes through independent lateral transfer of their precursors from bacteria or bacteriophages. In addition to these, multiple adenine and cytosine methylases were acquired by several families of eukaryotic transposons. In eukaryotes, the DNA-methylase module was often combined with distinct modified and unmodified peptide recognition domains and other modules mediating specialized interactions, for example, the RFD module of DNMT1 which contains a permuted Sm domain linked to a helix-turn-helix domain. In eukaryotes, the evolution of DNA methylases appears to have proceeded in parallel to the elaboration of histone-modifying enzymes and the RNAi system, with functions related to counter-viral and counter-transposon defense, and regulation of DNA repair and differential gene expression being their primary ancestral functions. Diverse DNA demethylation systems that utilize base-excision repair via DNA glycosylases and cytosine deaminases appear to have emerged in multiple eukaryotic lineages. Comparative genomics suggests that the link between cytosine methylation and DNA glycosylases probably emerged first in a novel R-M system in bacteria. Recent studies suggest that the 5mC is not

  1. System and method for producing substitute natural gas from coal

    Science.gov (United States)

    Hobbs, Raymond [Avondale, AZ

    2012-08-07

    The present invention provides a system and method for producing substitute natural gas and electricity, while mitigating production of any greenhouse gasses. The system includes a hydrogasification reactor, to form a gas stream including natural gas and a char stream, and an oxygen burner to combust the char material to form carbon oxides. The system also includes an algae farm to convert the carbon oxides to hydrocarbon material and oxygen.

  2. From Continuous to Discontinuous Transitions in Social Diffusion

    Directory of Open Access Journals (Sweden)

    Paula Tuzón

    2018-03-01

    Full Text Available Models of social diffusion reflect processes of how new products, ideas, or behaviors are adopted in a population. These models typically lead to a continuous or a discontinuous phase transition of the number of adopters as a function of a control parameter. We explore a simple model of social adoption where the agents can be in two states, either adopters or non-adopters, and can switch between these two states interacting with other agents through a network. The probability of an agent to switch from non-adopter to adopter depends on the number of adopters in her network neighborhood, the adoption threshold T and the adoption coefficient a, two parameters defining a Hill function. In contrast, the transition from adopter to non-adopter is spontaneous at a certain rate μ. In a mean-field approach, we derive the governing ordinary differential equations and show that the nature of the transition between the global non-adoption and global adoption regimes depends mostly on the balance between the probability to adopt with one and two adopters. The transition changes from continuous, via a transcritical bifurcation, to discontinuous, via a combination of a saddle-node and a transcritical bifurcation, through a supercritical pitchfork bifurcation. We characterize the full parameter space. Finally, we compare our analytical results with Monte Carlo simulations on annealed and quenched degree regular networks, showing a better agreement for the annealed case. Our results show how a simple model is able to capture two seemingly very different types of transitions, i.e., continuous and discontinuous and thus unifies underlying dynamics for different systems. Furthermore, the form of the adoption probability used here is based on empirical measurements.

  3. Actor Bonds in Situations of Discontinuous Business Activities

    DEFF Research Database (Denmark)

    Skaates, Maria Anne

    2000-01-01

    in situations of discontinuity. Therefore an analysis and comparison of relevant concepts that capture the key generative features of actor bonds in both socially constructed networks and socially constructed markets is undertaken. These concepts include the "milieu" of project marketing (Cova et al., 1996......Demand in many industrial buying situations, e.g. project purchases or procurement related to virtual organizations, is discontinuous. In situations of discontinuity, networks are often more of an ad hos informational and social nature, as strong activity and resource links are not present......) and the institutional concept of the "field". Finally this paper introduces the concept of "social capital" (Bourdieu, 1983) and discusses whether it can be used to conceptualize the dynamic features of actor bonds in situations of discontinuity....

  4. Local Conceptualisation of Nature, Forest Knowledge Systems and ...

    African Journals Online (AJOL)

    The results show that the concept of nature is well embedded in the social representation of the vital space of the people of the study area. Three forest management knowledge systems were derived from this concept of nature that combines the space, the time, the supernatural and the distance between forests and its ...

  5. Linking human and natural systems in the planning process

    Science.gov (United States)

    Susan I. Stewart; Miranda H. Mockrin; Roger B. Hammer

    2012-01-01

    Planning links human and natural systems in the urban-rural interface by engaging people in consideration of the future of natural resources. We review evolving ideas about what planning entails, who it involves, and what its outcomes should be. Sense of place, collaboration, emergent planning, and other new developments in planning are discussed. Smaller plans,...

  6. The South African national non-natural mortality surveillance system ...

    African Journals Online (AJOL)

    Background. While individual mortuaries have recorded data for non-natural deaths in time-limited studies, there have been no systematic efforts to draw forensic-medical services and state mortuaries into a nationwide fatal injury surveillance system. Beginning in June 1998, the National Non-Natural Mortality Surveillance ...

  7. Natural coordinates for a class of Benenti systems

    International Nuclear Information System (INIS)

    Blaszak, Maciej; Sergyeyev, Artur

    2007-01-01

    We present explicit formulas for the coordinates in which the Hamiltonians of the Benenti systems with flat metrics take natural form and the metrics in question are represented by constant diagonal matrices

  8. Natural coordinates for a class of Benenti systems

    Energy Technology Data Exchange (ETDEWEB)

    Blaszak, Maciej [Institute of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)]. E-mail: blaszakm@amu.edu.pl; Sergyeyev, Artur [Silesian University in Opava, Mathematical Institute, Na Rybnicku 1, 746 01 Opava (Czech Republic)]. E-mail: artur.sergyeyev@math.slu.cz

    2007-05-21

    We present explicit formulas for the coordinates in which the Hamiltonians of the Benenti systems with flat metrics take natural form and the metrics in question are represented by constant diagonal matrices.

  9. [The fate of nuclides in natural water systems

    International Nuclear Information System (INIS)

    Turekian, K.K.

    1989-01-01

    Our research at Yale on the fate of nuclides in natural water systems has three components to it: the study of the atmospheric precipitation of radionuclides and other chemical species; the study of the behavior of natural radionuclides in groundwater and hydrothermal systems; and understanding the controls on the distribution of radionuclides and stable nuclides in the marine realm. In this section a review of our progress in each of these areas is presented

  10. Study of Natural Convection Passive Cooling System for Nuclear Reactors

    Science.gov (United States)

    Abdillah, Habibi; Saputra, Geby; Novitrian; Permana, Sidik

    2017-07-01

    Fukushima nuclear reactor accident occurred due to the reactor cooling pumps and followed by all emergencies cooling systems could not work. Therefore, the system which has a passive safety system that rely on natural laws such as natural convection passive cooling system. In natural convection, the cooling material can flow due to the different density of the material due to the temperature difference. To analyze such investigation, a simple apparatus was set up and explains the study of natural convection in a vertical closed-loop system. It was set up that, in the closed loop, there is a heater at the bottom which is representing heat source system from the reactor core and cooler at the top which is showing the cooling system performance in room temperature to make a temperature difference for convection process. The study aims to find some loop configurations and some natural convection performances that can produce an optimum flow of cooling process. The study was done and focused on experimental approach and simulation. The obtained results are showing and analyzing in temperature profile data and the speed of coolant flow at some point on the closed-loop system.

  11. System reliability analysis with natural language and expert's subjectivity

    International Nuclear Information System (INIS)

    Onisawa, T.

    1996-01-01

    This paper introduces natural language expressions and expert's subjectivity to system reliability analysis. To this end, this paper defines a subjective measure of reliability and presents the method of the system reliability analysis using the measure. The subjective measure of reliability corresponds to natural language expressions of reliability estimation, which is represented by a fuzzy set defined on [0,1]. The presented method deals with the dependence among subsystems and employs parametrized operations of subjective measures of reliability which can reflect expert 's subjectivity towards the analyzed system. The analysis results are also expressed by linguistic terms. Finally this paper gives an example of the system reliability analysis by the presented method

  12. The Integrated Information System for Natural Disaster Mitigation

    Directory of Open Access Journals (Sweden)

    Junxiu Wu

    2007-08-01

    Full Text Available Supported by the World Bank, the Integrated Information System for Natural Disaster Mitigation (ISNDM, including the operational service system and network telecommunication system, has been in development for three years in the Center of Disaster Reduction, Chinese Academy of Sciences, based on the platform of the GIS software Arcview. It has five main modules: disaster background information, socio- economic information, disaster-induced factors database, disaster scenarios database, and disaster assessment. ISNDM has several significant functions, which include information collection, information processing, data storage, and information distribution. It is a simple but comprehensive demonstration system for our national center for natural disaster reduction.

  13. Contributions of the US state park system to nature recreation.

    Science.gov (United States)

    Siikamäki, Juha

    2011-08-23

    Nature recreation in the United States concentrates in publicly provided natural areas. They are costly to establish and maintain, but their societal contributions are difficult to measure. Here, a unique approach is developed to quantifying nature recreation services generated by the US state park system. The assessment first uses data from five national surveys conducted between 1975 and 2007 to consistently measure the amount of time used for nature recreation. The surveys comprise two official federal surveys and their predecessors. Each survey was designed to elicit nationally representative, detailed data on how people divide their time into different activities. State-level data on time use for nature recreation were then matched with information on the availability of state parks and other potentially important drivers of recreation, so that statistical estimation methods for nonexperimental panel data (difference-in-differences) could be used to examine the net contribution of state parks to nature recreation. The results show that state parks have a robust positive effect on nature recreation. For example, the approximately 2 million acres of state parks established between 1975 and 2007 are estimated to contribute annually 600 million hours of nature recreation (2.7 h per capita, approximately 9% of all nature recreation). All state parks generate annually an estimated 2.2 billion hours of nature recreation (9.7 h per capita; approximately 33% of all nature recreation). Using conventional approaches to valuing time, the estimated time value of nature recreation services generated by the US state park system is approximately $14 billion annually.

  14. Geometrical properties of a discontinuity network in gneissic rock, a case study in high alpine terrain

    Science.gov (United States)

    Koppensteiner, Matthias; Zangerl, Christian

    2017-04-01

    considered, the consistency is obvious. Scanline measurements and analyses provide siginificant results for discontinuity properties under the described circumstances. Considering sampling biases, the obtained dataset is even benefiting from the randomized sampling process, due to the natural terrain. The scanline survey provides a statistical database which can be used for rock mass characterization. Geometrical rock mass characterization is essential to model the in-situ block size distribution, to estimate the degree of fracturing and rock mass anisotropy for quarry oder tunnelling projects or define the mechanical rock mass properties based on classifications systems. The study should contribute a reference for the development and application of other methods for investigating discontinuity properties in instable rock masses.

  15. Numerical modeling of underground storage system for natural gas

    Science.gov (United States)

    Ding, J.; Wang, S.

    2017-12-01

    Natural gas is an important type of base-load energy, and its supply needs to be adjusted according to different demands in different seasons. For example, since natural gas is increasingly used to replace coal for winter heating, the demand for natural gas in winter is much higher than that in other seasons. As storage systems are the essential tools for balancing seasonal supply and demand, the design and simulation of natural gas storage systems form an important research direction. In this study, a large-scale underground storage system for natural gas is simulated based on theoretical analysis and finite element modeling.It is proven that the problem of axi-symmetric Darcy porous flow of ideal gas is governed by the Boussinesq equation. In terms of the exact solution to the Boussinesq equation, the basic operating characteristics of the underground storage system is analyzed, and it is demonstrated that the propagation distance of the pore pressure is proportional to the 1/4 power of the mass flow rate and to the 1/2 power of the propagation time. This quantitative relationship can be used to guide the overall design of natural gas underground storage systems.In order to fully capture the two-way coupling between pore pressure and elastic matrix deformation, a poro-elastic finite element model for natural gas storage is developed. Based on the numerical model, the dynamic processes of gas injection, storage and extraction are simulated, and the corresponding time-dependent surface deformations are obtained. The modeling results not only provide a theoretical basis for real-time monitoring for the operating status of the underground storage system through surface deformation measurements, but also demonstrate that a year-round balance can be achieved through periodic gas injection and extraction.This work is supported by the CAS "100 talents" Program and the National Natural Science Foundation of China (41371090).

  16. The Morphosyntax of Discontinuous Exponence

    Science.gov (United States)

    Campbell, Amy Melissa

    2012-01-01

    This thesis offers a systematic treatment of discontinuous exponence, a pattern of inflection in which a single feature or a set of features bundled in syntax is expressed by multiple, distinct morphemes. This pattern is interesting and theoretically relevant because it represents a deviation from the expected one-to-one relationship between…

  17. Discontinuing Medication: Recurrence Risk Factors

    OpenAIRE

    J Gordon Millichap

    1992-01-01

    The results of antiepileptic drug discontinuation in epileptic children who were seizure free for at least 2 years are reported from the Services of Child Neurology and Psychology, Department of Neurology, Clinics Hospital University of Sao Paulo Medical School, Sao Paulo, Brazil.

  18. Development of a natural Gas Systems Analysis Model (GSAM)

    International Nuclear Information System (INIS)

    Godec, M.; Haas, M.; Pepper, W.; Rose, J.

    1993-01-01

    Recent dramatic changes in natural gas markets have significant implications for the scope and direction of DOE's upstream as well as downstream natural gas R ampersand D. Open access transportation changes the way gas is bought and sold. The end of the gas deliverability surplus requires increased reserve development above recent levels. Increased gas demand for power generation and other new uses changes the overall demand picture in terms of volumes, locations and seasonality. DOE's Natural Gas Strategic Plan requires that its R ampersand D activities be evaluated for their ability to provide adequate supplies of reasonably priced gas. Potential R ampersand D projects are to be evaluated using a full fuel cycle, benefit-cost approach to estimate likely market impact as well as technical success. To assure R ampersand D projects are evaluated on a comparable basis, METC has undertaken the development of a comprehensive natural gas technology evaluation framework. Existing energy systems models lack the level of detail required to estimate the impact of specific upstream natural gas technologies across the known range of geological settings and likely market conditions. Gas Systems Analysis Model (GSAM) research during FY 1993 developed and implemented this comprehensive, consistent natural gas system evaluation framework. Rather than a isolated research activity, however, GSAM represents the integration of many prior and ongoing natural gas research efforts. When complete, it will incorporate the most current resource base description, reservoir modeling, technology characterization and other geologic and engineering aspects developed through recent METC and industry gas R ampersand D programs

  19. Benefit assessment of solar-augmented natural gas systems

    Science.gov (United States)

    Davis, E. S.; French, R. L.; Sohn, R. L.

    1980-01-01

    Report details how solar-energy-augmented system can reduce natural gas consumption by 40% to 70%. Applications discussed include: domestic hot water system, solar-assisted gas heat pumps, direct heating from storage tank. Industrial uses, solar-assisted appliances, and economic factors are discussed.

  20. Systemic Analysis of Sudden Natural Deaths at Braithwaite ...

    African Journals Online (AJOL)

    Peak age group was 30-39 years with 27.7%. Cardiovascular system pathologies were by far the commonest causes of death with 87.6%. The least cause of death was prematurity with 0.4%. Among the cardiovascular system pathologies, hypertensive heart disease was the commonest. All deathswere from natural causes.

  1. Natural Resources Information System for the State of Oklahoma

    International Nuclear Information System (INIS)

    Mankin, C.J.

    1992-01-01

    The objective of this research program was to continue developing, editing, maintaining, utilizing and making publicly available the Natural Resources Information System (NRIS) for the State of Oklahoma. The Oklahoma Geological Survey, working with Geological Information Systems at the University of Oklahoma's Sarkeys Energy Center, undertook to construct this information system in response to the need for a computerized, centrally located library containing accurate, detailed information on the state's natural resources. Particular emphasis during this phase of development was placed on computerizing information related to the energy needs of the nation, specifically oil and gas

  2. Design of natural user interface of indoor surveillance system

    Science.gov (United States)

    Jia, Lili; Liu, Dan; Jiang, Mu-Jin; Cao, Ning

    2015-03-01

    Conventional optical video surveillance systems usually just record what they view, but they can't make sense of what they are viewing. With lots of useless video information stored and transmitted, waste of memory space and increasing the bandwidth are produced every day. In order to reduce the overall cost of the system, and improve the application value of the monitoring system, we use the Kinect sensor with CMOS infrared sensor, as a supplement to the traditional video surveillance system, to establish the natural user interface system for indoor surveillance. In this paper, the architecture of the natural user interface system, complex background monitoring object separation, user behavior analysis algorithms are discussed. By the analysis of the monitoring object, instead of the command language grammar, when the monitored object need instant help, the system with the natural user interface sends help information. We introduce the method of combining the new system and traditional monitoring system. In conclusion, theoretical analysis and experimental results in this paper show that the proposed system is reasonable and efficient. It can satisfy the system requirements of non-contact, online, real time, higher precision and rapid speed to control the state of affairs at the scene.

  3. Novel food packaging systems with natural antimicrobial agents.

    Science.gov (United States)

    Irkin, Reyhan; Esmer, Ozlem Kizilirmak

    2015-10-01

    A new type of packaging that combines food packaging materials with antimicrobial substances to control microbial surface contamination of foods to enhance product microbial safety and to extend shelf-life is attracting interest in the packaging industry. Several antimicrobial compounds can be combined with different types of packaging materials. But in recent years, since consumer demand for natural food ingredients has increased because of safety and availability, these natural compounds are beginning to replace the chemical additives in foods and are perceived to be safer and claimed to alleviate safety concerns. Recent research studies are mainly focused on the application of natural antimicrobials in food packaging system. Biologically derived compounds like bacteriocins, phytochemicals, enzymes can be used in antimicrobial food packaging. The aim of this review is to give an overview of most important knowledge about application of natural antimicrobial packagings with model food systems and their antimicrobial effects on food products.

  4. Natural Language Assistant: A Dialog System for Online Product Recommendation

    OpenAIRE

    Chai, Joyce; Horvath, Veronika; Nicolov, Nicolas; Stys, Margo; Kambhatla, Nanda; Zadrozny, Wlodek; Melville, Prem

    2002-01-01

    With the emergence of electronic-commerce systems, successful information access on electroniccommerce web sites becomes essential. Menu-driven navigation and keyword search currently provided by most commercial sites have considerable limitations because they tend to overwhelm and frustrate users with lengthy, rigid, and ineffective interactions. To provide an efficient solution for information access, we have built the NATURAL language ASSISTANT (NLA), a web-based natural language dialog sy...

  5. Neither nature nor environment: Systemic operationalism and ecologism

    International Nuclear Information System (INIS)

    Gomez E, Luis F

    2009-01-01

    Nature is a complex concept that some critics have found as one of the roots of the current crisis of orthodox modernity. Because of this, we think ecologism should develop a theory where it does not play a pivotal role. Here, we propose systemic operationalism as a theoretical basis for ecologism since it seems to meet this requirement without having to replace it with terms such as environment which appears to keep some of the problems critics see in the concept of nature.

  6. A Large-Telescope Natural Guide Star AO System

    Science.gov (United States)

    Redding, David; Milman, Mark; Needels, Laura

    1994-01-01

    None given. From overview and conclusion:Keck Telescope case study. Objectives-low cost, good sky coverage. Approach--natural guide star at 0.8um, correcting at 2.2um.Concl- Good performance is possible for Keck with natural guide star AO system (SR>0.2 to mag 17+).AO-optimized CCD should b every effective. Optimizing td is very effective.Spatial Coadding is not effective except perhaps at extreme low light levels.

  7. Robust state estimation for neural networks with discontinuous activations.

    Science.gov (United States)

    Liu, Xiaoyang; Cao, Jinde

    2010-12-01

    Discontinuous dynamical systems, particularly neural networks with discontinuous activation functions, arise in a number of applications and have received considerable research attention in recent years. In this paper, the robust state estimation problem is investigated for uncertain neural networks with discontinuous activations and time-varying delays, where the neuron-dependent nonlinear disturbance on the network outputs are only assumed to satisfy the local Lipschitz condition. Based on the theory of differential inclusions and nonsmooth analysis, several criteria are presented to guarantee the existence of the desired robust state estimator for the discontinuous neural networks. It is shown that the design of the state estimator for such networks can be achieved by solving some linear matrix inequalities, which are dependent on the size of the time derivative of the time-varying delays. Finally, numerical examples are given to illustrate the theoretical results.

  8. Discontinuities, cross-scale patterns, and the organization of ecosystems

    Science.gov (United States)

    Nash, Kirsty L.; Allen, Craig R.; Angeler, David G.; Barichievy, Chris; Eason, Tarsha; Garmestani, Ahjond S.; Graham, Nicholas A.J.; Granholm, Dean; Knutson, Melinda; Nelson, R. John; Nystrom, Magnus; Stow, Craig A.; Sandstrom, Shana M.

    2014-01-01

    Ecological structures and processes occur at specific spatiotemporal scales, and interactions that occur across multiple scales mediate scale-specific (e.g., individual, community, local, or regional) responses to disturbance. Despite the importance of scale, explicitly incorporating a multi-scale perspective into research and management actions remains a challenge. The discontinuity hypothesis provides a fertile avenue for addressing this problem by linking measureable proxies to inherent scales of structure within ecosystems. Here we outline the conceptual framework underlying discontinuities and review the evidence supporting the discontinuity hypothesis in ecological systems. Next we explore the utility of this approach for understanding cross-scale patterns and the organization of ecosystems by describing recent advances for examining nonlinear responses to disturbance and phenomena such as extinctions, invasions, and resilience. To stimulate new research, we present methods for performing discontinuity analysis, detail outstanding knowledge gaps, and discuss potential approaches for addressing these gaps.

  9. Natural computing for mechanical systems research: A tutorial overview

    Science.gov (United States)

    Worden, Keith; Staszewski, Wieslaw J.; Hensman, James J.

    2011-01-01

    A great many computational algorithms developed over the past half-century have been motivated or suggested by biological systems or processes, the most well-known being the artificial neural networks. These algorithms are commonly grouped together under the terms soft or natural computing. A property shared by most natural computing algorithms is that they allow exploration of, or learning from, data. This property has proved extremely valuable in the solution of many diverse problems in science and engineering. The current paper is intended as a tutorial overview of the basic theory of some of the most common methods of natural computing as they are applied in the context of mechanical systems research. The application of some of the main algorithms is illustrated using case studies. The paper also attempts to give some indication as to which of the algorithms emerging now from the machine learning community are likely to be important for mechanical systems research in the future.

  10. The divergence and natural selection of autocatalytic primordial metabolic systems.

    Science.gov (United States)

    Marakushev, Sergey A; Belonogova, Ol'ga V

    2013-06-01

    The diversity of the central metabolism of modern organisms is caused by the existence of a few metabolic modules, combination of which produces multiple metabolic pathways. This paper analyzes biomimetically reconstructed coupled autocatalytic cycles as the basis of ancestral metabolic systems. The mechanism for natural selection and evolution in autocatalytic chemical systems may be affected by natural homeostatic parameters such as ambient chemical potentials, temperature, and pressure. Competition between separate parts of an autocatalytic network with positive-plus-negative feedback resulted in the formation of primordial autotrophic, mixotrophic, and heterotrophic metabolic systems. This work examined the last common ancestor of a set of coupled metabolic cycles in a population of protocells. Physical-chemical properties of these cycles determined the main principles of natural selection for the ancestral Bacteria and Archaea taxa.

  11. The Divergence and Natural Selection of Autocatalytic Primordial Metabolic Systems

    Science.gov (United States)

    Marakushev, Sergey A.; Belonogova, Ol'ga V.

    2013-06-01

    The diversity of the central metabolism of modern organisms is caused by the existence of a few metabolic modules, combination of which produces multiple metabolic pathways. This paper analyzes biomimetically reconstructed coupled autocatalytic cycles as the basis of ancestral metabolic systems. The mechanism for natural selection and evolution in autocatalytic chemical systems may be affected by natural homeostatic parameters such as ambient chemical potentials, temperature, and pressure. Competition between separate parts of an autocatalytic network with positive-plus-negative feedback resulted in the formation of primordial autotrophic, mixotrophic, and heterotrophic metabolic systems. This work examined the last common ancestor of a set of coupled metabolic cycles in a population of protocells. Physical-chemical properties of these cycles determined the main principles of natural selection for the ancestral Bacteria and Archaea taxa.

  12. Discontinuous almost automorphic functions and almost automorphic solutions of differential equations with piecewise constant arguments

    Directory of Open Access Journals (Sweden)

    Alan Chavez

    2014-02-01

    Full Text Available In this article we introduce a class of discontinuous almost automorphic functions which appears naturally in the study of almost automorphic solutions of differential equations with piecewise constant argument. Their fundamental properties are used to prove the almost automorphicity of bounded solutions of a system of differential equations with piecewise constant argument. Due to the strong discrete character of these equations, the existence of a unique discrete almost automorphic solution of a non-autonomous almost automorphic difference system is obtained, for which conditions of exponential dichotomy and discrete Bi-almost automorphicity are fundamental.

  13. A Note on Stress Function Discontinuities in Plane Plastic Bending ...

    African Journals Online (AJOL)

    The variational and differential equation formulations of the stress function problem for combined plane bending and torsion of a fully plastic material are discussed. The nature of discontinuities to be expected as well as the actual degree of correspondence between the two formulations is determined. A modification of the ...

  14. Strategies for discontinuation of proton pump inhibitors

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja S; Begtrup, Luise M

    2014-01-01

    PURPOSE: Proton pump inhibitors (PPIs) are considered to be overprescribed. Consensus on how to attempt discontinuation is, however, lacking. We therefore conducted a systematic review of clinical studies on discontinuation of PPIs. METHODS: Systematic review based on clinical studies investigating...

  15. Innovating Big Data Computing Geoprocessing for Analysis of Engineered-Natural Systems

    Science.gov (United States)

    Rose, K.; Baker, V.; Bauer, J. R.; Vasylkivska, V.

    2016-12-01

    Big data computing and analytical techniques offer opportunities to improve predictions about subsurface systems while quantifying and characterizing associated uncertainties from these analyses. Spatial analysis, big data and otherwise, of subsurface natural and engineered systems are based on variable resolution, discontinuous, and often point-driven data to represent continuous phenomena. We will present examples from two spatio-temporal methods that have been adapted for use with big datasets and big data geo-processing capabilities. The first approach uses regional earthquake data to evaluate spatio-temporal trends associated with natural and induced seismicity. The second algorithm, the Variable Grid Method (VGM), is a flexible approach that presents spatial trends and patterns, such as those resulting from interpolation methods, while simultaneously visualizing and quantifying uncertainty in the underlying spatial datasets. In this presentation we will show how we are utilizing Hadoop to store and perform spatial analyses to efficiently consume and utilize large geospatial data in these custom analytical algorithms through the development of custom Spark and MapReduce applications that incorporate ESRI Hadoop libraries. The team will present custom `Big Data' geospatial applications that run on the Hadoop cluster and integrate with ESRI ArcMap with the team's probabilistic VGM approach. The VGM-Hadoop tool has been specially built as a multi-step MapReduce application running on the Hadoop cluster for the purpose of data reduction. This reduction is accomplished by generating multi-resolution, non-overlapping, attributed topology that is then further processed using ESRI's geostatistical analyst to convey a probabilistic model of a chosen study region. Finally, we will share our approach for implementation of data reduction and topology generation via custom multi-step Hadoop applications, performance benchmarking comparisons, and Hadoop

  16. Catastrophes in nature and society mathematical modeling of complex systems

    CERN Document Server

    Khlebopros, Rem G; Fet, Abram I

    2007-01-01

    Many people are concerned about crises leading to disasters in nature, in social and economic life. The book offers a popular account of the causative mechanisms of critical states and breakdown in a broad range of natural and cultural systems - which obey the same laws - and thus makes the reader aware of the origin of catastrophic events and the ways to avoid and mitigate their negative consequences. The authors apply a single mathematical approach to investigate the revolt of cancer cells that destroy living organisms and population outbreaks that upset natural ecosystems, the balance between biosphere and global climate interfered lately by industry, the driving mechanisms of market and related economic and social phenomena, as well as the electoral system the proper use of which is an arduous accomplishment of democracy.

  17. Nature-inspired design of hybrid intelligent systems

    CERN Document Server

    Castillo, Oscar; Kacprzyk, Janusz

    2017-01-01

    This book highlights recent advances in the design of hybrid intelligent systems based on nature-inspired optimization and their application in areas such as intelligent control and robotics, pattern recognition, time series prediction, and optimization of complex problems. The book is divided into seven main parts, the first of which addresses theoretical aspects of and new concepts and algorithms based on type-2 and intuitionistic fuzzy logic systems. The second part focuses on neural network theory, and explores the applications of neural networks in diverse areas, such as time series prediction and pattern recognition. The book’s third part presents enhancements to meta-heuristics based on fuzzy logic techniques and describes new nature-inspired optimization algorithms that employ fuzzy dynamic adaptation of parameters, while the fourth part presents diverse applications of nature-inspired optimization algorithms. In turn, the fifth part investigates applications of fuzzy logic in diverse areas, such as...

  18. Farmers\\' Discontinuance Decision Behaviours Of Yam Minisett ...

    African Journals Online (AJOL)

    Farmers' discontinuance decision behaviours of technologies is attributed to certain reasons and it is governed by certain socio-economic variables. This study identified and analyzed the rate of discontinuance of yam minisett technology, reasons for discontinuance and the socio-economic determinants of the ...

  19. Leveraging natural dynamical structures to explore multi-body systems

    Science.gov (United States)

    Bosanac, Natasha

    Multi-body systems have become the target of an increasing number of mission concepts and observations, supplying further information about the composition, origin and dynamical environment of bodies within the solar system and beyond. In many of these scenarios, identification and characterization of the particular solutions that exist in a circular restricted three-body model is valuable. This insight into the underlying natural dynamical structures is achieved via the application of dynamical systems techniques. One application of such analysis is trajectory design for CubeSats, which are intended to explore cislunar space and other planetary systems. These increasingly complex mission objectives necessitate innovative trajectory design strategies for spacecraft within our solar system, as well as the capability for rapid and well-informed redesign. Accordingly, a trajectory design framework is constructed using dynamical systems techniques and demonstrated for the Lunar IceCube mission. An additional application explored in this investigation involves the motion of an exoplanet near a binary star system. Due to the strong gravitational field near a binary star, physicists have previously leveraged these systems as testbeds for examining the validity of gravitational and relativistic theories. In this investigation, a preliminary analysis into the effect of an additional three-body interaction on the dynamical environment near a large mass ratio binary system is conducted. As demonstrated through both of these sample applications, identification and characterization of the natural particular solutions that exist within a multi-body system supports a well-informed and guided analysis.

  20. Corruption in Russia - Historic Legacy and Systemic Nature

    OpenAIRE

    Schulze, Günther G.; Zakharov, Nikita

    2018-01-01

    This paper argues that corruption in Russia is systemic in nature. Low wage levels of public officials provide strong incentives to engage in corruption. As corruption is illegal, corrupt officials can be exposed any time, which enforces loyalty towards the powers that be; thus corruption is a method of governance. We trace the systemic corruption back to the Mongolian empire and demonstrate its persistence to the current regime. We show the geographic distribution of contemporary corruption ...

  1. Darboux polynomials and first integrals of natural polynomial Hamiltonian systems

    International Nuclear Information System (INIS)

    Maciejewski, Andrzej J.; Przybylska, Maria

    2004-01-01

    We show that for a natural polynomial Hamiltonian system the existence of a single Darboux polynomial (a partial polynomial first integral) is equivalent to the existence of an additional first integral functionally independent with the Hamiltonian function. Moreover, we show that, in a case when the degree of potential is odd, the system does not admit any proper Darboux polynomial, i.e., the only Darboux polynomials are first integrals

  2. A system for tritium analysis in natural water

    International Nuclear Information System (INIS)

    Mozeto, A.A.

    1977-01-01

    A method for the analysis, by scintillation counting, of tritium in natural water enriched electrolytically, is presented. The characteristics of the proposed system are indicated by experimental parameters, and by the performance obtained in the analysis of rain and under ground waters. An evaluation of the precison and reproducibility of the measurements is also made [pt

  3. Disturbance of SH-type waves due to moving stress discontinuity in ...

    Indian Academy of Sciences (India)

    The disturbance and propagation of SH-type waves in an anisotropic soil layer overlying an inhomogeneous elastic half-space by a moving stress discontinuity is considered. Stress discontinuity moves with non-uniform velocity and is impulsive in nature. The displacements are obtained in exact form by themethod due to ...

  4. Disturbance of SH-type waves due to moving stress discontinuity in ...

    Indian Academy of Sciences (India)

    Abstract. The disturbance and propagation of SH-type waves in an anisotropic soil layer overlying an inhomogeneous elastic half-space by a moving stress discontinuity is considered. Stress discontinuity moves with non-uniform velocity and is impulsive in nature. The displacements are obtained in exact form by the method ...

  5. Including natural systems into the system engineering process: benefits to spaceflight and beyond

    Science.gov (United States)

    Studor, George

    2014-03-01

    How did we get to the point where we don't have time to be inspired by the wonders of Nature? Our office walls, homes and city streets are so plain that even when we do escape to a retreat with nature all around us, we may be blind to its magnificence. Yet there are many who have applied what can be known of natural systems (NS) to create practical solutions, but often definite applications for them are lacking. Mimicry of natural systems is not only more possible than ever before, but the education and research programs in many major universities are churning out graduates with a real appreciation for Nature's complex integrated systems. What if these skills and perspectives were employed in the teams of systems engineers and the technology developers that support them to help the teams think "outside-the-box" of manmade inventions? If systems engineers (SE) and technology developers regularly asked the question, "what can we learn from Nature that will help us?" as a part of their processes, they would discover another set of potential solutions. Biomimicry and knowledge of natural systems is exploding. What does this mean for systems engineering and technology? Some disciplines such as robotics and medical devices must consider nature constantly. Perhaps it's time for all technology developers and systems engineers to perceive natural systems experts as potential providers of the technologies they need.

  6. Methane Leaks from Natural Gas Systems Follow Extreme Distributions.

    Science.gov (United States)

    Brandt, Adam R; Heath, Garvin A; Cooley, Daniel

    2016-11-15

    Future energy systems may rely on natural gas as a low-cost fuel to support variable renewable power. However, leaking natural gas causes climate damage because methane (CH 4 ) has a high global warming potential. In this study, we use extreme-value theory to explore the distribution of natural gas leak sizes. By analyzing ∼15 000 measurements from 18 prior studies, we show that all available natural gas leakage data sets are statistically heavy-tailed, and that gas leaks are more extremely distributed than other natural and social phenomena. A unifying result is that the largest 5% of leaks typically contribute over 50% of the total leakage volume. While prior studies used log-normal model distributions, we show that log-normal functions poorly represent tail behavior. Our results suggest that published uncertainty ranges of CH 4 emissions are too narrow, and that larger sample sizes are required in future studies to achieve targeted confidence intervals. Additionally, we find that cross-study aggregation of data sets to increase sample size is not recommended due to apparent deviation between sampled populations. Understanding the nature of leak distributions can improve emission estimates, better illustrate their uncertainty, allow prioritization of source categories, and improve sampling design. Also, these data can be used for more effective design of leak detection technologies.

  7. Limits to natural variation: implications for systemic management

    Directory of Open Access Journals (Sweden)

    Fowler, C. W.

    2002-12-01

    Full Text Available Collectively, the tenets and principles of management emphasize the importance of recognizing and understanding limits. These tenets require the demonstration, measurement and practical use of information about limits to natural variation. It is important to identify limits so as not to incur the risks and loss of integrity when limits are exceeded. Thus, by managing within natural limits, humans (managers simultaneously can achieve sustainability and minimize risk, as well as account for complexity. This is at the heart of systemic management. Systemic management embodies the basic tenets of management. One tenet requires that management ensure that nothing exceed the limits observed in its natural variation. This tenet is based on the principle that variation is constrained by a variety of limiting factors, many of which involve risks. Another tenet of management requires that such factors be considered simultaneously, exhaustively, and in proportion to their relative importance. These factors, in combination, make up the complexity that managers are required to consider in applying the basic principles of management. This combination of elements is reflected in observed limits to natural variation that account for each factor and its relative importance. This paper summarizes conclusions from the literature that has addressed the concept of limits to natural variation, especially in regard to management. It describes: 1. How such limits are inherent to complex systems; 2. How limits have been recognized to be important to the process of management; 3. How they can be used in management. The inherent limits include both those set by the context in which systems occur (extrinsic factors as well as those set by the components and processes within systems (intrinsic factors. This paper shows that information about limits is of utility in guiding human action to fit humans within the normal range of natural variation. This is part of systemic

  8. Occupy the Financial Niche – Saturation and Crisis (discontinuous decisions

    Directory of Open Access Journals (Sweden)

    Ionut PURICA

    2014-09-01

    Full Text Available The model presented is proposing an approach that could verify the nonlinear behaviour during a crisis, such that to quantify and predict potential discontinuous behaviour. In this case, the crisis behaviour associated with financial funds reallocation among various credit instruments, described as memes with the sense of Dawkins, is shown to be of discontinuous nature stemming from a logistic penetration in the financial behaviour niche. Actually the logistic penetration is typical in creating cyclic behaviour of economic structures as shown by Marchetti and others from IIASA. A Fokker-Planck equation description results in a stationary solution having a bifurcation like solution with evolution trajectories on a ‘cusp’ type catastrophe that may describe discontinuous decision behaviour

  9. Modeling shallow water flows using the discontinuous Galerkin method

    CERN Document Server

    Khan, Abdul A

    2014-01-01

    Replacing the Traditional Physical Model Approach Computational models offer promise in improving the modeling of shallow water flows. As new techniques are considered, the process continues to change and evolve. Modeling Shallow Water Flows Using the Discontinuous Galerkin Method examines a technique that focuses on hyperbolic conservation laws and includes one-dimensional and two-dimensional shallow water flows and pollutant transports. Combines the Advantages of Finite Volume and Finite Element Methods This book explores the discontinuous Galerkin (DG) method, also known as the discontinuous finite element method, in depth. It introduces the DG method and its application to shallow water flows, as well as background information for implementing and applying this method for natural rivers. It considers dam-break problems, shock wave problems, and flows in different regimes (subcritical, supercritical, and transcritical). Readily Adaptable to the Real World While the DG method has been widely used in the fie...

  10. A non-conventional discontinuous Lagrangian for viscous flow

    Science.gov (United States)

    Marner, F.

    2017-01-01

    Drawing an analogy with quantum mechanics, a new Lagrangian is proposed for a variational formulation of the Navier–Stokes equations which to-date has remained elusive. A key feature is that the resulting Lagrangian is discontinuous in nature, posing additional challenges apropos the mathematical treatment of the related variational problem, all of which are resolvable. In addition to extending Lagrange's formalism to problems involving discontinuous behaviour, it is demonstrated that the associated equations of motion can self-consistently be interpreted within the framework of thermodynamics beyond local equilibrium, with the limiting case recovering the classical Navier–Stokes equations. Perspectives for applying the new formalism to discontinuous physical phenomena such as phase and grain boundaries, shock waves and flame fronts are provided. PMID:28386415

  11. Modeling shallow water flows using the discontinuous galerkin method

    CERN Document Server

    Khan, Abdul A

    2014-01-01

    Replacing the Traditional Physical Model Approach Computational models offer promise in improving the modeling of shallow water flows. As new techniques are considered, the process continues to change and evolve. Modeling Shallow Water Flows Using the Discontinuous Galerkin Method examines a technique that focuses on hyperbolic conservation laws and includes one-dimensional and two-dimensional shallow water flows and pollutant transports. Combines the Advantages of Finite Volume and Finite Element Methods This book explores the discontinuous Galerkin (DG) method, also known as the discontinuous finite element method, in depth. It introduces the DG method and its application to shallow water flows, as well as background information for implementing and applying this method for natural rivers. It considers dam-break problems, shock wave problems, and flows in different regimes (subcritical, supercritical, and transcritical). Readily Adaptable to the Real World While the DG method has been widely used in the fie...

  12. Deliverability on the interstate natural gas pipeline system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    Deliverability on the Interstate Natural Gas Pipeline System examines the capability of the national pipeline grid to transport natural gas to various US markets. The report quantifies the capacity levels and utilization rates of major interstate pipeline companies in 1996 and the changes since 1990, as well as changes in markets and end-use consumption patterns. It also discusses the effects of proposed capacity expansions on capacity levels. The report consists of five chapters, several appendices, and a glossary. Chapter 1 discusses some of the operational and regulatory features of the US interstate pipeline system and how they affect overall system design, system utilization, and capacity expansions. Chapter 2 looks at how the exploration, development, and production of natural gas within North America is linked to the national pipeline grid. Chapter 3 examines the capability of the interstate natural gas pipeline network to link production areas to market areas, on the basis of capacity and usage levels along 10 corridors. The chapter also examines capacity expansions that have occurred since 1990 along each corridor and the potential impact of proposed new capacity. Chapter 4 discusses the last step in the transportation chain, that is, deliverability to the ultimate end user. Flow patterns into and out of each market region are discussed, as well as the movement of natural gas between States in each region. Chapter 5 examines how shippers reserve interstate pipeline capacity in the current transportation marketplace and how pipeline companies are handling the secondary market for short-term unused capacity. Four appendices provide supporting data and additional detail on the methodology used to estimate capacity. 32 figs., 15 tabs.

  13. RURAL TOURISM IN ROMANIA - EVOLUTIONS AND DISCONTINUITIES

    Directory of Open Access Journals (Sweden)

    Ionica SOARE

    2011-12-01

    Full Text Available This paper analyzes the evolution of rural tourism since the early '70s, the time of onset, and indicates the discontinuity recorded especially after 1989 until the brink of the preparation for Romania's joining the European Union and the present state, one far behind the countries with extremely high degree of urbanization and industrialization, probably as a result of a lack of strategy for this form of tourism in which the beneficiary is the Ministry of Tourism, as the health tourism and ecotourism have recently had. The location of many villages in areas of outstanding natural landscapes, the richness and variety of cultural heritage that endows them, are issues related to an increased tourism potential that can be capitalized and those unique tourism products that can not be seen, admired and offered by other countries.

  14. Thermodynamic Modeling of Natural Gas Systems Containing Water

    DEFF Research Database (Denmark)

    Karakatsani, Eirini K.; Kontogeorgis, Georgios M.

    2013-01-01

    As the need for dew point specifications remains very urgent in the natural gas industry, the development of accurate thermodynamic models, which will match experimental data and will allow reliable extrapolations, is needed. Accurate predictions of the gas phase water content in equilibrium...... with a heavy phase were previously obtained using cubic plus association (CPA) coupled with a solid phase model in the case of hydrates, for the binary systems of water–methane and water–nitrogen and a few natural gas mixtures. In this work, CPA is being validated against new experimental data, both water...... content and phase equilibrium data, and solid model parameters are being estimated for four natural gas main components (methane, ethane, propane, and carbon dioxide). Different tests for the solid model parameters are reported, including vapor-hydrate-equilibria (VHE) and liquid-hydrate-equilibria (LHE...

  15. Conflicting Epistemologies and Inference in Coupled Human and Natural Systems

    Science.gov (United States)

    Garcia, M. E.

    2017-12-01

    Last year, I presented a model that projects per capita water consumption based on changes in price, population, building codes, and water stress salience. This model applied methods from hydrological science and engineering to relationships both within and beyond their traditional scope. Epistemologically, the development of mathematical models of natural or engineered systems is objectivist while research examining relationships between observations, perceptions and action is commonly constructivist or subjectivist. Drawing on multiple epistemologies is common in, and perhaps central to, the growing fields of coupled human and natural systems, and socio-hydrology. Critically, these philosophical perspectives vary in their view of the nature of the system as mechanistic, adaptive or constructed, and the split between aleatory and epistemic uncertainty. Interdisciplinary research is commonly cited as a way to address the critical and domain crossing challenge of sustainability as synthesis across perspectives can offer a more comprehensive view of system dynamics. However, combining methods and concepts from multiple ontologies and epistemologies can introduce contradictions into the logic of inference. These contractions challenge the evaluation of research products and the implications for practical application of research findings are not fully understood. Reflections on the evaluation, application, and generalization of the water consumption model described above are used to ground these broader questions and offer thoughts on the way forward.

  16. Performance study of an innovative natural gas CHP system

    International Nuclear Information System (INIS)

    Fu, Lin; Zhao, Xiling; Zhang, Shigang; Li, Yan; Jiang, Yi; Li, Hui; Sun, Zuoliang

    2011-01-01

    In the last decade, technological innovation and changes in the economic and regulatory environment have resulted in increased attention to distributed energy systems (DES). Combined cooling heating and power (CHP) systems based on the gas-powered internal combustion engine (ICE) are increasingly used as small-scale distribution co-generators. This paper describes an innovative ICE-CHP system with an exhaust-gas-driven absorption heat pump (AHP) that has been set up at the energy-saving building in Beijing, China. The system is composed of an ICE, an exhaust-gas-driven AHP, and a flue gas condensation heat exchanger (CHE), which could recover both the sensible and latent heat of the flue gas. The steady performance and dynamic response of the innovative CHP system with different operation modes were tested. The results show that the system's energy utilization efficiency could reach above 90% based on lower heating value (LHV) of natural gas; that is, the innovative CHP system could increase the heat utilization efficiency 10% compared to conventional CHP systems, and the thermally activated components of the system have much more thermal inertia than the electricity generation component. The detailed test results provide important insight into CHP performance characteristics and could be valuable references for the control of CHP systems. The novel CHP system could take on a very important role in the CHP market. (author)

  17. Emergent Properties in Natural and Artificial Dynamical Systems

    CERN Document Server

    Aziz-Alaoui, M.A

    2006-01-01

    An important part of the science of complexity is the study of emergent properties arising through dynamical processes in various types of natural and artificial systems. This is the aim of this book, which is the outcome of a discussion meeting within the first European conference on complex systems. It presents multidisciplinary approaches for getting representations of complex systems and using different methods to extract emergent structures. This carefully edited book studies emergent features such as self organization, synchronization, opening on stability and robustness properties. Invariant techniques are presented which can express global emergent properties in dynamical and in temporal evolution systems. This book demonstrates how artificial systems such as a distributed platform can be used for simulation used to search emergent placement during simulation execution.

  18. On the Nature of the Hagedorn Transition in NCOS Systems

    CERN Document Server

    Barbón, José L F

    2001-01-01

    We extend the study of the nature of the Hagedorn transition in NCOS systems in various dimensions. The canonical analysis results in a microscopic ionization picture of a bound state system in which the Hagedorn transition is postponed till irrelevancy. A microcanonical analysis leads to a limiting Hagedorn behaviour dominated by highly excited, long open strings. The study of the full phase diagram of the NCOS system using the AdS/CFT correspondence suggests that the microscopic ionization picture is the correct one. We discuss some refinements of the ionization mechanism for $d>2$ NCOS systems, including the formation of a temperature-dependent barrier for the process. Some possible consequences of this behaviour, including a potential puzzle for $d=5$, are discussed. Phase diagrams of a regularized form of NCOS systems are introduced and do accomodate a phase of long open strings which disappears in the strict NCOS limit.

  19. Local CHP Plants between the Natural Gas and Electricity Systems

    DEFF Research Database (Denmark)

    Bregnbæk, Lars; Schaumburg-Müller, Camilla

    2005-01-01

    , and they contribute significantly to the electricity production. CHP is, together with the wind power, the almost exclusive distributed generation in Denmark. This paper deals with the CHP as intermediary between the natural gas system and the electricity system. In particular, the relationship between the peak hour......Local combined heat and power (CHP) plants in Denmark constitute an important part of the national energy conversion capacity. In particular they supply a large share of the district heating networks with heat. At the same time they are important consumers as seen from the gas network system...... characteristics of the electricity and gas systems will be investigated. The point is here that the two systems will tend to have peak demand during the same hours. This is the typical situation, since load is high during the same hours of the day and of the year. Moreover, the random variations in the load...

  20. Rock discontinuity surface roughness variation with scale

    Science.gov (United States)

    Bitenc, Maja; Kieffer, D. Scott; Khoshelham, Kourosh

    2017-04-01

    ABSTRACT: Rock discontinuity surface roughness refers to local departures of the discontinuity surface from planarity and is an important factor influencing the shear resistance. In practice, the Joint Roughness Coefficient (JRC) roughness parameter is commonly relied upon and input to a shear strength criterion such as developed by Barton and Choubey [1977]. The estimation of roughness by JRC is hindered firstly by the subjective nature of visually comparing the joint profile to the ten standard profiles. Secondly, when correlating the standard JRC values and other objective measures of roughness, the roughness idealization is limited to a 2D profile of 10 cm length. With the advance of measuring technologies that provide accurate and high resolution 3D data of surface topography on different scales, new 3D roughness parameters have been developed. A desirable parameter is one that describes rock surface geometry as well as the direction and scale dependency of roughness. In this research a 3D roughness parameter developed by Grasselli [2001] and adapted by Tatone and Grasselli [2009] is adopted. It characterizes surface topography as the cumulative distribution of local apparent inclination of asperities with respect to the shear strength (analysis) direction. Thus, the 3D roughness parameter describes the roughness amplitude and anisotropy (direction dependency), but does not capture the scale properties. In different studies the roughness scale-dependency has been attributed to data resolution or size of the surface joint (see a summary of researches in [Tatone and Grasselli, 2012]). Clearly, the lower resolution results in lower roughness. On the other hand, have the investigations of surface size effect produced conflicting results. While some studies have shown a decrease in roughness with increasing discontinuity size (negative scale effect), others have shown the existence of positive scale effects, or both positive and negative scale effects. We

  1. Rotational discontinuities in anisotropic plasmas

    International Nuclear Information System (INIS)

    Omidi, N.

    1992-01-01

    The kinetic structure of rotational discontinuities (RDs) in anisotropic plasmas with T perpendicular /T parallel > 1 is investigated by using a one-dimensional electromagnetic hybrid code. To form the RD, a new approach is used where the plasma is injected from one boundary and reflected from the other, resulting in the generation of a traveling fast shock and an RD. Unlike the previously used methods, no a priori assumptions are made regarding the initial structure (i.e. width or sense of rotation) of the rotational discontinuity. The results show that across the RD both the magnetic field strength and direction, as well as the plasma density change. Given that such a change can also be associated with an intermediate shock, the Rankine-Hugoniot relations are used to confirm that the observed structures are indeed RDs. It is found that the thickness of RDs is a few ion inertial lengths and is independent of the rotation angle. Also, the preferred sense of rotation is in the electron sense; however, RDs with a rotation angle larger than 180 degree are found to be unstable, changing their rotation to a stable ion sense

  2. Some rock mass assessment procedures for discontinuous crystalline rock

    International Nuclear Information System (INIS)

    Boodt, P.I.; Brown, E.T.

    1985-03-01

    Underground radioactive waste repositories place especially stringent demands on rock mass assessment and excavation design methodologies. As part of the Building Research Establishment's programme of research into geotechnical site assessment methodology, experiments were undertaken at an underground test site in granite at Troon, Cornwall, and in the Imperial College Laboratories. The results of discontinuity surveys showed that the borehole impression packer probe technique can provide an important source of information for radioactive waste repository site assessment. Similarly, borehole pressure tests can provide valuable data on discontinuity apertures and hydraulic conductivities and on rock mass permeabilities. A versatile, modular borehole pressure test system for use from restricted underground locations was developed and used successfully. Field tests gave values of equivalent parallel plate apertures and discontinuity hydraulic conductivities in similar ranges to those measured in laboratory tests on samples recovered from the site. Discontinuity normal stiffnesses were also measured successfully using the Terra Tek Geothermal Rock Mechanics Test System which proved itself capable of providing laboratory test data required to support geotechnical site assessment procedures for radioactive waste repositories in discontinuous rock. (author)

  3. Artificial intelligence, expert systems, computer vision, and natural language processing

    Science.gov (United States)

    Gevarter, W. B.

    1984-01-01

    An overview of artificial intelligence (AI), its core ingredients, and its applications is presented. The knowledge representation, logic, problem solving approaches, languages, and computers pertaining to AI are examined, and the state of the art in AI is reviewed. The use of AI in expert systems, computer vision, natural language processing, speech recognition and understanding, speech synthesis, problem solving, and planning is examined. Basic AI topics, including automation, search-oriented problem solving, knowledge representation, and computational logic, are discussed.

  4. Exploiting Lexical Regularities in Designing Natural Language Systems.

    Science.gov (United States)

    1988-04-01

    ELEMENT. PROJECT. TASKN Artificial Inteligence Laboratory A1A4WR NTumet 0) 545 Technology Square Cambridge, MA 02139 Ln *t- CONTROLLING OFFICE NAME AND...RO-RI95 922 EXPLOITING LEXICAL REGULARITIES IN DESIGNING NATURAL 1/1 LANGUAGE SYSTENS(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE...oes.ary and ftdou.Ip hr Nl wow" L,2This paper presents the lexical component of the START Question Answering system developed at the MIT Artificial

  5. Environmental and natural resource implications of sustainable urban infrastructure systems

    Science.gov (United States)

    Bergesen, Joseph D.; Suh, Sangwon; Baynes, Timothy M.; Kaviti Musango, Josephine

    2017-12-01

    As cities grow, their environmental and natural resource footprints also tend to grow to keep up with the increasing demand on essential urban services such as passenger transportation, commercial space, and thermal comfort. The urban infrastructure systems, or socio-technical systems providing these services are the major conduits through which natural resources are consumed and environmental impacts are generated. This paper aims to gauge the potential reductions in environmental and resources footprints through urban transformation, including the deployment of resource-efficient socio-technical systems and strategic densification. Using hybrid life cycle assessment approach combined with scenarios, we analyzed the greenhouse gas (GHG) emissions, water use, metal consumption and land use of selected socio-technical systems in 84 cities from the present to 2050. The socio-technical systems analyzed are: (1) bus rapid transit with electric buses, (2) green commercial buildings, and (3) district energy. We developed a baseline model for each city considering gross domestic product, population density, and climate conditions. Then, we overlaid three scenarios on top of the baseline model: (1) decarbonization of electricity, (2) aggressive deployment of resource-efficient socio-technical systems, and (3) strategic urban densification scenarios to each city and quantified their potentials in reducing the environmental and resource impacts of cities by 2050. The results show that, under the baseline scenario, the environmental and natural resource footprints of all 84 cities combined would increase 58%-116% by 2050. The resource-efficient scenario along with strategic densification, however, has the potential to curve down GHG emissions to 17% below the 2010 level in 2050. Such transformation can also limit the increase in all resource footprints to less than 23% relative to 2010. This analysis suggests that resource-efficient urban infrastructure and decarbonization of

  6. GeoCEGAS: natural gas distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Lorena C.J. [Companhia de Gas do Ceara (CEGAS), Fortaleza, CE (Brazil); Targa, Fernando O. [Gestao Empresarial e Informatica Ltda. (GEMPI), Sao Paulo, SP (Brazil)

    2009-07-01

    This Technical Paper approach the conception, architecture, design, construction, and implementation of GeoCEGAS, a spatially enabled corporate management information system, oriented to store and provide Web access, to information associated with the natural gas distribution network, owned by CEGAS. This paper reports business processes, business entities and business intelligence approached on the project, as well as an overview of system architecture, applications, and technology used on the implementation of GeoCEGAS. Finally, is presented an introduction to the work methodology used, as well a synopsis of benefits achievements. (author)

  7. Escherichia coli is naturally transformable in a novel transformation system.

    Science.gov (United States)

    Sun, Dongchang; Zhang, Yanmei; Mei, Yunjun; Jiang, Hui; Xie, Zhixiong; Liu, Huihui; Chen, Xiangdong; Shen, Ping

    2006-12-01

    A novel transformation system, in which neither a nonphysiological concentration of Ca2+ and temperature shifts nor electronic shocks were required, was developed to determine whether Escherichia coli is naturally transformable. In the new protocol, E. coli was cultured normally to the stationary phase and then cultured statically at 37 degrees C in Luria-Bertani broth. After static culture, transformation occurred in bacteria spread on Luria-Bertani plates. The protein synthesis inhibitor chloramphenicol inhibited this transformation process. The need for protein synthesis in plated bacteria suggests that the transformation of E. coli in this new system is regulated physiologically.

  8. Natural selection and self-organization in complex adaptive systems.

    Science.gov (United States)

    Di Bernardo, Mirko

    2010-01-01

    The central theme of this work is self-organization "interpreted" both from the point of view of theoretical biology, and from a philosophical point of view. By analysing, on the one hand, those which are now considered--not only in the field of physics--some of the most important discoveries, that is complex systems and deterministic chaos and, on the other hand, the new frontiers of systemic biology, this work highlights how large thermodynamic systems which are open can spontaneously stay in an orderly regime. Such systems can represent the natural source of the order required for a stable self-organization, for homoeostasis and for hereditary variations. The order, emerging in enormous randomly interconnected nets of binary variables, is almost certainly only the precursor of similar orders emerging in all the varieties of complex systems. Hence, this work, by finding new foundations for the order pervading the living world, advances the daring hypothesis according to which Darwinian natural selection is not the only source of order in the biosphere. Thus, the article, by examining the passage from Prigogine's dissipative structures theory to the contemporary theory of biological complexity, highlights the development of a coherent and continuous line of research which is set to individuate the general principles marking the profound reality of that mysterious self-organization characterizing the complexity of life.

  9. Natural language processing in biomedicine: a unified system architecture overview.

    Science.gov (United States)

    Doan, Son; Conway, Mike; Phuong, Tu Minh; Ohno-Machado, Lucila

    2014-01-01

    In contemporary electronic medical records much of the clinically important data-signs and symptoms, symptom severity, disease status, etc.-are not provided in structured data fields but rather are encoded in clinician-generated narrative text. Natural language processing (NLP) provides a means of unlocking this important data source for applications in clinical decision support, quality assurance, and public health. This chapter provides an overview of representative NLP systems in biomedicine based on a unified architectural view. A general architecture in an NLP system consists of two main components: background knowledge that includes biomedical knowledge resources and a framework that integrates NLP tools to process text. Systems differ in both components, which we review briefly. Additionally, the challenge facing current research efforts in biomedical NLP includes the paucity of large, publicly available annotated corpora, although initiatives that facilitate data sharing, system evaluation, and collaborative work between researchers in clinical NLP are starting to emerge.

  10. A common type system for clinical natural language processing

    Directory of Open Access Journals (Sweden)

    Wu Stephen T

    2013-01-01

    Full Text Available Abstract Background One challenge in reusing clinical data stored in electronic medical records is that these data are heterogenous. Clinical Natural Language Processing (NLP plays an important role in transforming information in clinical text to a standard representation that is comparable and interoperable. Information may be processed and shared when a type system specifies the allowable data structures. Therefore, we aim to define a common type system for clinical NLP that enables interoperability between structured and unstructured data generated in different clinical settings. Results We describe a common type system for clinical NLP that has an end target of deep semantics based on Clinical Element Models (CEMs, thus interoperating with structured data and accommodating diverse NLP approaches. The type system has been implemented in UIMA (Unstructured Information Management Architecture and is fully functional in a popular open-source clinical NLP system, cTAKES (clinical Text Analysis and Knowledge Extraction System versions 2.0 and later. Conclusions We have created a type system that targets deep semantics, thereby allowing for NLP systems to encapsulate knowledge from text and share it alongside heterogenous clinical data sources. Rather than surface semantics that are typically the end product of NLP algorithms, CEM-based semantics explicitly build in deep clinical semantics as the point of interoperability with more structured data types.

  11. A common type system for clinical natural language processing.

    Science.gov (United States)

    Wu, Stephen T; Kaggal, Vinod C; Dligach, Dmitriy; Masanz, James J; Chen, Pei; Becker, Lee; Chapman, Wendy W; Savova, Guergana K; Liu, Hongfang; Chute, Christopher G

    2013-01-03

    One challenge in reusing clinical data stored in electronic medical records is that these data are heterogenous. Clinical Natural Language Processing (NLP) plays an important role in transforming information in clinical text to a standard representation that is comparable and interoperable. Information may be processed and shared when a type system specifies the allowable data structures. Therefore, we aim to define a common type system for clinical NLP that enables interoperability between structured and unstructured data generated in different clinical settings. We describe a common type system for clinical NLP that has an end target of deep semantics based on Clinical Element Models (CEMs), thus interoperating with structured data and accommodating diverse NLP approaches. The type system has been implemented in UIMA (Unstructured Information Management Architecture) and is fully functional in a popular open-source clinical NLP system, cTAKES (clinical Text Analysis and Knowledge Extraction System) versions 2.0 and later. We have created a type system that targets deep semantics, thereby allowing for NLP systems to encapsulate knowledge from text and share it alongside heterogenous clinical data sources. Rather than surface semantics that are typically the end product of NLP algorithms, CEM-based semantics explicitly build in deep clinical semantics as the point of interoperability with more structured data types.

  12. A data management system to enable urgent natural disaster computing

    Science.gov (United States)

    Leong, Siew Hoon; Kranzlmüller, Dieter; Frank, Anton

    2014-05-01

    Civil protection, in particular natural disaster management, is very important to most nations and civilians in the world. When disasters like flash floods, earthquakes and tsunamis are expected or have taken place, it is of utmost importance to make timely decisions for managing the affected areas and reduce casualties. Computer simulations can generate information and provide predictions to facilitate this decision making process. Getting the data to the required resources is a critical requirement to enable the timely computation of the predictions. An urgent data management system to support natural disaster computing is thus necessary to effectively carry out data activities within a stipulated deadline. Since the trigger of a natural disaster is usually unpredictable, it is not always possible to prepare required resources well in advance. As such, an urgent data management system for natural disaster computing has to be able to work with any type of resources. Additional requirements include the need to manage deadlines and huge volume of data, fault tolerance, reliable, flexibility to changes, ease of usage, etc. The proposed data management platform includes a service manager to provide a uniform and extensible interface for the supported data protocols, a configuration manager to check and retrieve configurations of available resources, a scheduler manager to ensure that the deadlines can be met, a fault tolerance manager to increase the reliability of the platform and a data manager to initiate and perform the data activities. These managers will enable the selection of the most appropriate resource, transfer protocol, etc. such that the hard deadline of an urgent computation can be met for a particular urgent activity, e.g. data staging or computation. We associated 2 types of deadlines [2] with an urgent computing system. Soft-hard deadline: Missing a soft-firm deadline will render the computation less useful resulting in a cost that can have severe

  13. Evaluation of system codes for analyzing naturally circulating gas loop

    International Nuclear Information System (INIS)

    Lee, Jeong Ik; No, Hee Cheon; Hejzlar, Pavel

    2009-01-01

    Steady-state natural circulation data obtained in a 7 m-tall experimental loop with carbon dioxide and nitrogen are presented in this paper. The loop was originally designed to encompass operating range of a prototype gas-cooled fast reactor passive decay heat removal system, but the results and conclusions are applicable to any natural circulation loop operating in regimes having buoyancy and acceleration parameters within the ranges validated in this loop. Natural circulation steady-state data are compared to numerical predictions by two system analysis codes: GAMMA and RELAP5-3D. GAMMA is a computational tool for predicting various transients which can potentially occur in a gas-cooled reactor. The code has a capability of analyzing multi-dimensional multi-component mixtures and includes models for friction, heat transfer, chemical reaction, and multi-component molecular diffusion. Natural circulation data with two gases show that the loop operates in the deteriorated turbulent heat transfer (DTHT) regime which exhibits substantially reduced heat transfer coefficients compared to the forced turbulent flow. The GAMMA code with an original heat transfer package predicted conservative results in terms of peak wall temperature. However, the estimated peak location did not successfully match the data. Even though GAMMA's original heat transfer package included mixed-convection regime, which is a part of the DTHT regime, the results showed that the original heat transfer package could not reproduce the data with sufficient accuracy. After implementing a recently developed correlation and corresponding heat transfer regime map into GAMMA to cover the whole range of the DTHT regime, we obtained better agreement with the data. RELAP5-3D results are discussed in parallel.

  14. The natural defense system and the normative self model.

    Science.gov (United States)

    Kourilsky, Philippe

    2016-01-01

    Infectious agents are not the only agressors, and the immune system is not the sole defender of the organism. In an enlarged perspective, the 'normative self model' postulates that a 'natural defense system' protects man and other complex organisms against the environmental and internal hazards of life, including infections and cancers. It involves multiple error detection and correction mechanisms that confer robustness to the body at all levels of its organization. According to the model, the self relies on a set of physiological norms, and NONself (meaning : Non Obedient to the Norms of the self) is anything 'off-norms'. The natural defense system comprises a set of 'civil defenses' (to which all cells in organs and tissues contribute), and a 'professional army ', made of a smaller set of mobile cells. Mobile and non mobile cells differ in their tuning abilities. Tuning extends the recognition capabilities of NONself by the mobile cells, which increase their defensive function. To prevent them to drift, which would compromise self/NONself discrimination, the more plastic mobile cells need to periodically refer to the more stable non mobile cells to keep within physiological standards.

  15. Regression Discontinuity Designs Based on Population Thresholds

    DEFF Research Database (Denmark)

    Eggers, Andrew C.; Freier, Ronny; Grembi, Veronica

    ) to measure the effects of these threshold-based policies on political and economic outcomes. Using evidence from France, Germany, and Italy, we highlight two common pitfalls that arise in exploiting population-based policies (confounded treatment and sorting) and we provide guidance for detecting......In many countries, important features of municipal government (such as the electoral system, mayors' salaries, and the number of councillors) depend on whether the municipality is above or below arbitrary population thresholds. Several papers have used a regression discontinuity design (RDD...... and addressing these pitfalls. Even when these problems are present, population-threshold RDD may be the best available research design for studying the effects of certain policies and political institutions....

  16. Representativeness assessment of research natural areas on National Forest System lands in Idaho

    Science.gov (United States)

    Steven K. Rust

    2000-01-01

    A representativeness assessment of National Forest System (NFS) Research Natural Areas in Idaho summarizes information on the status of the natural area network and priorities for identification of new Research Natural Areas. Natural distribution and abundance of plant associations is compared to the representation of plant associations within natural areas. Natural...

  17. Mollified birth in natural-age-grid Galerkin methods for age-structured biological systems

    International Nuclear Information System (INIS)

    Ayati, Bruce P; Dupont, Todd F

    2009-01-01

    We present natural-age-grid Galerkin methods for a model of a biological population undergoing aging. We use a mollified birth term in the method and analysis. The error due to mollification is of arbitrary order, depending on the choice of mollifier. The methods in this paper generalize the methods presented in [1], where the approximation space in age was taken to be a discontinuous piecewise polynomial subspace of L 2 . We refer to these methods as 'natural-age-grid' Galerkin methods since transport in the age variable is computed through the smooth movement of the age grid at the natural dimensionless velocity of one. The time variable has been left continuous to emphasize this smooth motion, as well as the independence of the time and age discretizations. The methods are shown to be superconvergent in the age variable

  18. Local discontinuous Galerkin methods for phase transition problems

    NARCIS (Netherlands)

    Tian, Lulu

    2015-01-01

    In this thesis we develop a local discontinuous Galerkin (LDG) finite element method to solve mathematical models for phase transitions in solids and fluids. The first model we study is called a viscosity-capillarity (VC) system associated with phase transitions in elastic bars and Van der Waals

  19. Connectivity and discontinuity in social work practice: Challenges and opportunities of the implementation of an e-social work system in Romania

    Directory of Open Access Journals (Sweden)

    Anca Mihai

    2016-12-01

    Full Text Available To increase the efficiency of the social work system in Romania, “investments in improving the current IT system in order to build an efficient electronic social work system” (Romanian Government, 2015b, 85 and the “development of a modern payment system” (Romanian Government, 2015b, 85 are key-points in the National Strategy concerning Social Inclusion and Poverty Reduction for the period 2015-2020. Among other utilisations, the e-social work system is meant to be used by potential clients when submitting a request to benefit of means-tested measures. The current level of digitalisation of the Romanian society, particularly among vulnerable groups, leaves room for constructive debate regarding the feasibility and the potential challenges of such a project. The purpose of this paper is to identify the challenges posed to social workers’ daily practice by the introduction of digitalisation in the work place, as well as its potential effects on the social worker-client professional relationship. We discuss based on the national strategies and data provided by the Digital Economy and Society Index (DESI (connectivity infrastructure and quality, digital skills of human capital, use of internet by citizens, integration and digital technology, and digital public services. We identify gaps between the aims and the proposed solutions concerning the e-social work system. Our study contributes to understanding the potential changes in social workers’ traditional roles brought forth by the implementation of a digitized social work system.

  20. Natural Preconditioning and Iterative Methods for Saddle Point Systems

    KAUST Repository

    Pestana, Jennifer

    2015-01-01

    © 2015 Society for Industrial and Applied Mathematics. The solution of quadratic or locally quadratic extremum problems subject to linear(ized) constraints gives rise to linear systems in saddle point form. This is true whether in the continuous or the discrete setting, so saddle point systems arising from the discretization of partial differential equation problems, such as those describing electromagnetic problems or incompressible flow, lead to equations with this structure, as do, for example, interior point methods and the sequential quadratic programming approach to nonlinear optimization. This survey concerns iterative solution methods for these problems and, in particular, shows how the problem formulation leads to natural preconditioners which guarantee a fast rate of convergence of the relevant iterative methods. These preconditioners are related to the original extremum problem and their effectiveness - in terms of rapidity of convergence - is established here via a proof of general bounds on the eigenvalues of the preconditioned saddle point matrix on which iteration convergence depends.

  1. Water: Challenges at the Intersection of Human and Natural Systems

    Energy Technology Data Exchange (ETDEWEB)

    Futrell, J.H.; Gephart, R. E.; Kabat-Lensch, E.; McKnight, D. M.; Pyrtle, A.; Schimel, J. P.; Smyth, R. L.; Skole, D. L. Wilson, J. L.; Gephart, J. M.

    2005-09-01

    There is a growing recognition about the critical role water plays in sustaining people and society. This workshop established dialog between disciplinary scientists and program managers from diverse backgrounds in order to share perspectives and broaden community understanding of ongoing fundamental and applied research on water as a complex environmental problem. Three major scientific themes emerged: (1) coupling of cycles and process, with emphasis on the role of interfaces; (2) coupling of human and natural systems across spatial and temporal scales; and (3) prediction in the face of uncertainty. In addition, the need for observation systems, sensors, and infrastructure; and the need for data management and synthesis were addressed. Current barriers to progress were noted as educational and institutional barriers and the integration of science and policy.

  2. A transportable system of models for natural resource damage assessment

    International Nuclear Information System (INIS)

    Reed, M.; French, D.

    1992-01-01

    A system of computer models has been developed for assessment of natural resource economic damages resulting from spills of oil and hazardous materials in marine and fresh water environments. Under USA federal legislation, the results of the model system are presumed correct in damage litigation proceedings. The model can address a wide range of spatial and temporal scales. The equations describing the motion of both pollutants and biota are solved in three dimensions. The model can simulate continuous releases of a contaminant, with representation of complex coastal boundaries, variable bathymetry, multiple shoreline types, and spatially variable ecosystem habitats. A graphic user interface provides easy control of the system in addition to the ability to display elements of the underlying geographical information system data base. The model is implemented on a personal computer and on a UNIX workstation. The structure of the system is such that transport to new geographic regions can be accomplished relatively easily, requiring only the development of the appropriate physical, toxicological, biological, and economic data sets. Applications are currently in progress for USA inland and coastal waters, the Adriatic Sea, the Strait of Sicily, the Gulf of Suez, and the Baltic Sea. 4 refs., 2 figs

  3. El Paso natural gas nearing completion of system's largest expansion

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    El Paso Natural Gas Co.'s largest expansion program in its 64-year history will be completed along its northern system this spring or early summer. According to the company, the three-tiered, $241.5 million expansion program will increase El Paso's gas-transport capacity by 835 MMcfd to 2.5 bcfd of conventional and coal-seam gas from the San Juan basin in northwestern New Mexico. That's enough natural gas, says the company, to supply the needs of a city of more than 800,000 residents. This paper reports that the expansion involves the San Juan Triangle system, the company's northern main line, and the Permian-San Juan crossover line. The company also filed with the Federal Energy Regulatory Commission (FERC) in October 1991 to construct a new $15.2 million compressor station, Rio Vista, south of Bloomfield, N.M. The station would be used to move additional gas to the main line

  4. Discontinuation of Preventive Drugs in General Practice

    DEFF Research Database (Denmark)

    Andersen, John Sahl; Lindberg, Laura Maria Glahder; Nixon, Michael Simon

    of death in the United States. The public expenses to drug treatment are constantly increasing. The possibility to withdraw the medication must be taken into account but the decision to discontinue drugs is complex and poorly understood. Planned studies: 1. Patients’ views upon discontinuation...

  5. Discontinuities during UV writing of waveguides

    DEFF Research Database (Denmark)

    Svalgaard, Mikael; Harpøth, Anders; Andersen, Marc

    2005-01-01

    UV writing of waveguides can be hampered by discontinuities where the index change process suddenly shuts down. We show that thermal effects may account for this behaviour.......UV writing of waveguides can be hampered by discontinuities where the index change process suddenly shuts down. We show that thermal effects may account for this behaviour....

  6. Vertebral Fractures After Discontinuation of Denosumab

    DEFF Research Database (Denmark)

    Cummings, Steven R; Ferrari, Serge; Eastell, Richard

    2018-01-01

    Denosumab reduces bone resorption and vertebral and nonvertebral fracture risk. Denosumab discontinuation increases bone turnover markers 3 months after a scheduled dose is omitted, reaching above-baseline levels by 6 months, and decreases bone mineral density (BMD) to baseline levels by 12 months....... We analyzed the risk of new or worsening vertebral fractures, especially multiple vertebral fractures, in participants who discontinued denosumab during the FREEDOM study or its Extension. Participants received ≥2 doses of denosumab or placebo Q6M, discontinued treatment, and stayed in the study ≥7...... months after the last dose. Of 1001 participants who discontinued denosumab during FREEDOM or Extension, the vertebral fracture rate increased from 1.2 per 100 participant-years during the on-treatment period to 7.1, similar to participants who received and then discontinued placebo (n = 470; 8.5 per 100...

  7. Green's function approach to neutron flux discontinuities

    International Nuclear Information System (INIS)

    Saad, E.A.; El-Wakil, S.A.

    1980-01-01

    The present work is devoted to the presentation of analytical method for the calculation of elastically and inelastically slowed down neutrons in an infinite non-absorbing medium. On the basis of the central limit theory (CLT) and the integral transform technique the slowing down equation including inelastic scattering, in terms of the Green function of elastic scattering, is solved. The Green function is decomposed according to the number of collisions. Placzec discontinuity associated with elastic scattering in addition to two discontinuities due to inelastic scattering are investigated. Numerical calculations for Fe 56 show that the elastic discontinuity produces about 41.8% change in the collision density whilst the ratio of the inelastic collision density discontinuity at qsub(o)sup(+) to the Placzec discontinuity at usub(o) + 1n 1/oc gives 55.7 percent change. (author)

  8. Design of a Natural Gas Liquefaction System with Minimum Components

    International Nuclear Information System (INIS)

    Bergese, Franco

    2004-01-01

    In this work an economic method for liquefying natural gas by diminishing its temperature by means of the Joule-Thomson effect is presented.The pressures from and to which the gas must be expanded arose from a thermodynamic calculation optimizing the cost per unit mass of Liquefied Natural Gas LNG).It was determined that the gas should be expanded from 200 atm to 4 atm.This expansion ratio can be used in different scales.Large Scale: liquefaction of gas at well.It takes advantage of the fact that the gas inside the well is stored at high pressure.The gas is expanded in a valve / nozzle and then compressed to the pressure of the local pipeline system.The objective of this project is to export natural gas as LNG, which is transported by ships to the markets of consumption.Using this method of liquefaction, the LNG production levels are limited to a fraction of the production of the well, due to the injection of the un condensed gas into the local pipelines system.Medium Scale: A high pressure pipeline is the source of the gas.The expansion is performed and then the gas is again compressed to the pressure of a lower pressure pipeline into which the gas is injected.The pressure reductions of natural gas are performed nearby big cities.The aim of this project scale is the storage of fuel for gas thermal power plants during periods of low energy consumption for later burning when the resource is limited. Another possibility that offers this size of plant is the transportation of gas to regions where the resource is unavailable.This transportation would be carried out by means of cistern trucks, in the same way that conventional liquid fuels are transported.Small scale: the place of production would be a CNG refueling station. The source of gas is in this case a gas pipeline of urban distribution and the gas should be compressed with the compressor of the refueling station.Compressors have generally low loading factor and the periods of time when they are not producing

  9. The systemic nature of mustard lung: Comparison with COPD patients

    Directory of Open Access Journals (Sweden)

    Shahriary Alireza

    2017-11-01

    Full Text Available Sulphur mustard (SM is a powerful blister-causing alkylating chemical warfare agent used by Iraqi forces against Iran. One of the known complications of mustard gas inhalation is mustard lung which is discussed as a phenotype of chronic obstructive pulmonary disease (COPD. In this complication, there are clinical symptoms close to COPD with common etiologies, such as in smokers. Based on information gradually obtained by conducting the studies on mustard lung patients, systemic symptoms along with pulmonary disorders have attracted the attention of researchers. Changes in serum levels of inflammatory markers, such as C-reactive protein (CRP, tumor necrosis factor alpha (TNF-α, nuclear factor κB (NF-κB, matrix metalloproteinases (MMPs, interleukin (IL, chemokines, selectins, immunoglobulins, and signs of imbalance in oxidant-antioxidant system at serum level, present the systemic changes in these patients. In addition to these, reports of extra-pulmonary complications, such as osteoporosis and cardiovascular disease are also presented. In this study, the chance of developing the systemic nature of this lung disease have been followed on using the comparative study of changes in the mentioned markers in mustard lung and COPD patients at stable phases and the mechanisms of pathogenesis and phenomena, such as airway remodeling in these patients.

  10. Sustainable Water Management in Urban, Agricultural, and Natural Systems

    Directory of Open Access Journals (Sweden)

    Tess Russo

    2014-12-01

    Full Text Available Sustainable water management (SWM requires allocating between competing water sector demands, and balancing the financial and social resources required to support necessary water systems. The objective of this review is to assess SWM in three sectors: urban, agricultural, and natural systems. This review explores the following questions: (1 How is SWM defined and evaluated? (2 What are the challenges associated with sustainable development in each sector? (3 What are the areas of greatest potential improvement in urban and agricultural water management systems? And (4 What role does country development status have in SWM practices? The methods for evaluating water management practices range from relatively simple indicator methods to integration of multiple models, depending on the complexity of the problem and resources of the investigators. The two key findings and recommendations for meeting SWM objectives are: (1 all forms of water must be considered usable, and reusable, water resources; and (2 increasing agricultural crop water production represents the largest opportunity for reducing total water consumption, and will be required to meet global food security needs. The level of regional development should not dictate sustainability objectives, however local infrastructure conditions and financial capabilities should inform the details of water system design and evaluation.

  11. Historical transformation and epistemological discontinuity

    Directory of Open Access Journals (Sweden)

    Močnik Rastko

    2013-01-01

    Full Text Available Starting from recent formulas of EU bureaucracy for subordinating scientific and educational apparatuses to the needs of the capital and to the requests of its political representatives, the article analyses the interconnection between the historical transformation of the ideological state apparatuses (universities, higher education institutions, research institutes etc. and the epistemological discontinuity provoked by the triumph of technosciences. The hypothesis to be tested is the following: While the crisis of West European-North American capitalism requires an ever tighter submission of ideological state apparatuses, and especially of scientific and academic apparatuses to the needs of the capital, theoretical practices in the humanities and social sciences have come to the point where they entered into an open conflict with the domination of the capital and have, as a consequence, started to subvert their own institutional supports in the ideological apparatuses of the capitalist state. For this purpose, the article reconsiders social sciences as a compromise formation and, eventually, reassesses the historical materialism as a non-Cartesian modern science.

  12. Organic materials in planetary and protoplanetary systems: nature or nurture?

    Science.gov (United States)

    Dalle Ore, C. M.; Fulchignoni, M.; Cruikshank, D. P.; Barucci, M. A.; Brunetto, R.; Campins, H.; de Bergh, C.; Debes, J. H.; Dotto, E.; Emery, J. P.; Grundy, W. M.; Jones, A. P.; Mennella, V.; Orthous-Daunay, F. R.; Owen, T.; Pascucci, I.; Pendleton, Y. J.; Pinilla-Alonso, N.; Quirico, E.; Strazzulla, G.

    2011-09-01

    Aims: The objective of this work is to summarize the discussion of a workshop aimed at investigating the properties, origins, and evolution of the materials that are responsible for the red coloration of the small objects in the outer parts of the solar system. Because of limitations or inconsistencies in the observations and, until recently, the limited availability of laboratory data, there are still many questions on the subject. Our goal is to approach two of the main questions in a systematic way: - Is coloring an original signature of materials that are presolar in origin ("nature") or stems from post-formational chemical alteration, or weathering ("nurture")? - What is the chemical signature of the material that causes spectra to be sloped towards the red in the visible? We examine evidence available both from the laboratory and from observations sampling different parts of the solar system and circumstellar regions (disks). Methods: We present a compilation of brief summaries gathered during the workshop and describe the evidence towards a primordial vs. evolutionary origin for the material that reddens the small objects in the outer parts of our, as well as in other, planetary systems. We proceed by first summarizing laboratory results followed by observational data collected at various distances from the Sun. Results: While laboratory experiments show clear evidence of irradiation effects, particularly from ion bombardment, the first obstacle often resides in the ability to unequivocally identify the organic material in the observations. The lack of extended spectral data of good quality and resolution is at the base of this problem. Furthermore, that both mechanisms, weathering and presolar, act on the icy materials in a spectroscopically indistinguishable way makes our goal of defining the impact of each mechanism challenging. Conclusions: Through a review of some of the workshop presentations and discussions, encompassing laboratory experiments as well

  13. Guiding climate change adaptation within vulnerable natural resource management systems.

    Science.gov (United States)

    Bardsley, Douglas K; Sweeney, Susan M

    2010-05-01

    Climate change has the potential to compromise the sustainability of natural resources in Mediterranean climatic systems, such that short-term reactive responses will increasingly be insufficient to ensure effective management. There is a simultaneous need for both the clear articulation of the vulnerabilities of specific management systems to climate risk, and the development of appropriate short- and long-term strategic planning responses that anticipate environmental change or allow for sustainable adaptive management in response to trends in resource condition. Governments are developing climate change adaptation policy frameworks, but without the recognition of the importance of responding strategically, regional stakeholders will struggle to manage future climate risk. In a partnership between the South Australian Government, the Adelaide and Mt Lofty Ranges Natural Resource Management Board and the regional community, a range of available research approaches to support regional climate change adaptation decision-making, were applied and critically examined, including: scenario modelling; applied and participatory Geographical Information Systems modelling; environmental risk analysis; and participatory action learning. As managers apply ideas for adaptation within their own biophysical and socio-cultural contexts, there would be both successes and failures, but a learning orientation to societal change will enable improvements over time. A base-line target for regional responses to climate change is the ownership of the issue by stakeholders, which leads to an acceptance that effective actions to adapt are now both possible and vitally important. Beyond such baseline knowledge, the research suggests that there is a range of tools from the social and physical sciences available to guide adaptation decision-making.

  14. The development of a natural gas transportation logistics management system

    International Nuclear Information System (INIS)

    Pereira dos Santos, Sidney; Eugenio Leal, Jose; Oliveira, Fabricio

    2011-01-01

    Efficient management of the natural gas business chain - based on pipeline transmission networks and taking into consideration the interaction among the main players (e.g., shippers, suppliers, transmission companies and local distribution companies) - requires the use of decision-making support systems. These support systems maximise resources and mitigate contingencies due to gas supply shortfalls, operational contingencies from scheduled and non-scheduled equipment outages and market demand shortfalls. This study presents a practical use for technologies, such as a thermohydraulic simulation of gas flow through pipelines, a Monte Carlo simulation for compressor station availability studies, an economic risk evaluation related to potential revenue losses and contractual penalties and linear programming for the maximisation of income and the minimisation of contractual penalties. The proposed system allows the optimum availability level to be defined and maintained by the Transporter (by installing reserve capacity) to mitigate losses related to revenue and contractual penalties. It also economically identifies, quantifies and justifies the installation of stand-by compressor units that can mitigate the Transporter's exposure to losses caused by capacity shortfalls as a consequence of scheduled and non-scheduled outages. - Highlights: → We present a DSS to help the decision on investments on spare compressor units of pipelines systems. → The system may be applied to new or existing projects. → The system is able to estimate the revenue losses and the contractual penalties. → An economical evaluation shows the NPV for each configuration of spare units. → The method was applied to the case study of the Bolivia-Brazil gas pipeline.

  15. Extending topological surgery to natural processes and dynamical systems.

    Directory of Open Access Journals (Sweden)

    Stathis Antoniou

    Full Text Available Topological surgery is a mathematical technique used for creating new manifolds out of known ones. We observe that it occurs in natural phenomena where a sphere of dimension 0 or 1 is selected, forces are applied and the manifold in which they occur changes type. For example, 1-dimensional surgery happens during chromosomal crossover, DNA recombination and when cosmic magnetic lines reconnect, while 2-dimensional surgery happens in the formation of tornadoes, in the phenomenon of Falaco solitons, in drop coalescence and in the cell mitosis. Inspired by such phenomena, we introduce new theoretical concepts which enhance topological surgery with the observed forces and dynamics. To do this, we first extend the formal definition to a continuous process caused by local forces. Next, for modeling phenomena which do not happen on arcs or surfaces but are 2-dimensional or 3-dimensional, we fill in the interior space by defining the notion of solid topological surgery. We further introduce the notion of embedded surgery in S3 for modeling phenomena which involve more intrinsically the ambient space, such as the appearance of knotting in DNA and phenomena where the causes and effect of the process lies beyond the initial manifold, such as the formation of black holes. Finally, we connect these new theoretical concepts with a dynamical system and we present it as a model for both 2-dimensional 0-surgery and natural phenomena exhibiting a 'hole drilling' behavior. We hope that through this study, topology and dynamics of many natural phenomena, as well as topological surgery itself, will be better understood.

  16. The Episodic Nature of Experience: A Dynamical Systems Analysis.

    Science.gov (United States)

    Sreekumar, Vishnu; Dennis, Simon; Doxas, Isidoros

    2017-07-01

    Context is an important construct in many domains of cognition, including learning, memory, and emotion. We used dynamical systems methods to demonstrate the episodic nature of experience by showing a natural separation between the scales over which within-context and between-context relationships operate. To do this, we represented an individual's emails extending over about 5 years in a high-dimensional semantic space and computed the dimensionalities of the subspaces occupied by these emails. Personal discourse has a two-scaled geometry with smaller within-context dimensionalities than between-context dimensionalities. Prior studies have shown that reading experience (Doxas, Dennis, & Oliver, 2010) and visual experience (Sreekumar, Dennis, Doxas, Zhuang, & Belkin, 2014) have a similar two-scaled structure. Furthermore, the recurrence plot of the emails revealed that experience is predictable and hierarchical, supporting the constructs of some influential theories of memory. The results demonstrate that experience is not scale-free and provide an important target for accounts of how experience shapes cognition. Copyright © 2016 Cognitive Science Society, Inc.

  17. A model integrating social-cultural concepts of nature into frameworks of interaction between social and natural systems

    DEFF Research Database (Denmark)

    Muhar, Andreas; Raymond, Christopher M.; van den Born, Riyan J.G.

    2018-01-01

    Existing frameworks for analysing interactions between social and natural systems (e.g. Social-Ecological Systems framework, Ecosystem Services concept) do not sufficiently consider and operationalize the dynamic interactions between people's values, attitudes and understandings of the human-nature...... relationship at both individual and collective levels. We highlight the relevance of individual and collective understandings of the human-nature relationship as influencing factors for environmental behaviour, which may be reflected in natural resource management conflicts, and review the diversity....... Integrating this model into existing frameworks provides a tool for the exploration of how social-cultural concepts of nature interact with existing contexts to influence governance of social-ecological systems....

  18. Markerless client-server augmented reality system with natural features

    Science.gov (United States)

    Ning, Shuangning; Sang, Xinzhu; Chen, Duo

    2017-10-01

    A markerless client-server augmented reality system is presented. In this research, the more extensive and mature virtual reality head-mounted display is adopted to assist the implementation of augmented reality. The viewer is provided an image in front of their eyes with the head-mounted display. The front-facing camera is used to capture video signals into the workstation. The generated virtual scene is merged with the outside world information received from the camera. The integrated video is sent to the helmet display system. The distinguishing feature and novelty is to realize the augmented reality with natural features instead of marker, which address the limitations of the marker, such as only black and white, the inapplicability of different environment conditions, and particularly cannot work when the marker is partially blocked. Further, 3D stereoscopic perception of virtual animation model is achieved. The high-speed and stable socket native communication method is adopted for transmission of the key video stream data, which can reduce the calculation burden of the system.

  19. Thermal dimensioning of wet natural draft cooling systems

    International Nuclear Information System (INIS)

    Bourillot, Claudine.

    1975-01-01

    The conventional models of calculating wet natural draft cooling systems include two different parts. First, the thermal calculation of the dispersion is made either with an ''exact'' method of separating convection and evaporation phenomena and taking account for the steam in exces in the saturated air, or with a ''simplified'' method considering the heat transfer in the whole as resulting of a difference in enthalpies. (The latter is the Merkel theory). Secondly, the draft equation is solved for calculating air flow rate. Values of the mass transfer coefficients and pressure drops of the dispersion being needed for the computation, test bench measurements are made by the designers. As for counter-current cooling systems the models of the dispersion calculation are one-dimensional models not allowing the radial flow and air temperature distributions to be simulated; exchanges inside the rain zone are also neglected. As for crossed-current cooling systems the flow geometry entails a more complicated two-dimensional model to be used for the dispersion. In both cases, the dependence on meteorological factors such as wind, height gradients of temperature, or sunny features are disregarded [fr

  20. Nature-aligned approaches to form students’ system motivation

    Directory of Open Access Journals (Sweden)

    Marina V. Ulyanova

    2017-01-01

    Full Text Available Sustainable development of the society involves the transition of the society from the current evolutional stage to a higher stage without revolutionary destruction of the existing frames of society. An individual, playing a prominent role in human history from time to time, is able to provide for the evolution of consciousness of the whole community, appearing on the top of the evolutional cone in the moment of passing of the system to the qualitatively new stage of its development. Only an integral individual, a person-creator possessing a high potential of harmony is able to accomplish such transition. The golden proportion of the social structure of the society implies a certain correlation of ontological categories of people, having personality orientation that characterizes them as a creator, consumer or destroyer. The modern approaches to education involve motivating a human being to self-improvement all his/her lifelong. The question is that, how much pedagogical systems correspond to the laws of harmony, which provide formation of social strata golden proportion structure considered not from the perspective of class position, but from the perspective of creative personality orientation. The analysis of the existing educational approaches showed, that the best indices satisfying the set social problem belong to noospheric pedagogics, based on nature-aligned methodology of teaching academic disciplines. It is built on principles of health protection and health development, intellectual potential, system motivation of an individual to self-perfection. Nature-aligned educational methodology is personality oriented and enables the student to accomplish object-subject transformation in the process of education, as a result of which, following the receipt of special educational knowledge, abilities and skills, he/she gets common educational abilities and skills, on the basis of which the processes of self-actualization, self

  1. Discontinuity Detection in the Shield Metal Arc Welding Process.

    Science.gov (United States)

    Cocota, José Alberto Naves; Garcia, Gabriel Carvalho; da Costa, Adilson Rodrigues; de Lima, Milton Sérgio Fernandes; Rocha, Filipe Augusto Santos; Freitas, Gustavo Medeiros

    2017-05-10

    This work proposes a new methodology for the detection of discontinuities in the weld bead applied in Shielded Metal Arc Welding (SMAW) processes. The detection system is based on two sensors-a microphone and piezoelectric-that acquire acoustic emissions generated during the welding. The feature vectors extracted from the sensor dataset are used to construct classifier models. The approaches based on Artificial Neural Network (ANN) and Support Vector Machine (SVM) classifiers are able to identify with a high accuracy the three proposed weld bead classes: desirable weld bead, shrinkage cavity and burn through discontinuities. Experimental results illustrate the system's high accuracy, greater than 90% for each class. A novel Hierarchical Support Vector Machine (HSVM) structure is proposed to make feasible the use of this system in industrial environments. This approach presented 96.6% overall accuracy. Given the simplicity of the equipment involved, this system can be applied in the metal transformation industries.

  2. Rangelands, pastoralists and governments: interlinked systems of people and nature.

    Science.gov (United States)

    Walker, Brian H; Janssen, Marco A

    2002-05-29

    We analyse commercially operated rangelands as coupled systems of people and nature. The biophysical components include: (i) the reduction and recovery of potential primary production, reflected as changes in grass production per unit of rainfall; (ii) changes in woody plants dependent on the grazing and fire regimes; and (iii) livestock and wool dynamics influenced by season, condition of the rangeland and numbers of wild and feral animals. The social components include the managers, who vary with regard to a range of cognitive abilities and lifestyle choices, and the regulators who vary in regard to policy goals. We compare agent-based and optimization models of a rangeland system. The agent-based model leads to recognition that policies select for certain management practices by creating a template that governs the trajectories of the behaviour of individuals, learning, and overall system dynamics. Conservative regulations reduce short-term loss in production but also restrict learning. A free-market environment leads to severe degradation but the surviving pastoralists perform well under subsequent variable conditions. The challenge for policy makers is to balance the needs for learning and for preventing excessive degradation. A genetic algorithm model optimizing for net discounted income and based on a population of management solutions (stocking rate, how much to suppress fire, etc.) indicates that robust solutions lead to a loss of about 40% compared with solutions where the sequence of rainfall was known in advance: this is a similar figure to that obtained from the agent-based model. We conclude that, on the basis of Levin's three criteria, rangelands with their livestock and human managers do constitute complex adaptive systems. If this is so, then command-and-control approaches to rangeland policy and management are bound to fail.

  3. Using a Remotely Piloted Aircraft System (RPAS) to analyze the stability of a natural rock slope

    Science.gov (United States)

    Salvini, Riccardo; Esposito, Giuseppe; Mastrorocco, Giovanni; Seddaiu, Marcello

    2016-04-01

    This paper describes the application of a rotary wing RPAS for monitoring the stability of a natural rock slope in the municipality of Vecchiano (Pisa, Italy). The slope under investigation is approximately oriented NNW-SSE and has a length of about 320 m; elevation ranges from about 7 to 80 m a.s.l.. The hill consists of stratified limestone, somewhere densely fractured, with dip direction predominantly oriented in a normal way respect to the slope. Fracture traces are present in variable lengths, from decimetre to metre, and penetrate inward the rock versant with thickness difficult to estimate, often exceeding one meter in depth. The intersection between different fracture systems and the slope surface generates rocky blocks and wedges of variable size that may be subject to phenomena of gravitational instability (with reference to the variation of hydraulic and dynamic conditions). Geometrical and structural info about the rock mass, necessary to perform the analysis of the slope stability, were obtained in this work from geo-referenced 3D point clouds acquired using photogrammetric and laser scanning techniques. In particular, a terrestrial laser scanning was carried out from two different point of view using a Leica Scanstation2. The laser survey created many shadows in the data due to the presence of vegetation in the lower parts of the slope and limiting the feasibility of geo-structural survey. To overcome such a limitation, we utilized a rotary wing Aibotix Aibot X6 RPAS geared with a Nikon D3200 camera. The drone flights were executed in manual modality and the images were acquired, according to the characteristics of the outcrops, under different acquisition angles. Furthermore, photos were captured very close to the versant (a few meters), allowing to produce a dense 3D point cloud (about 80 Ma points) by the image processing. A topographic survey was carried out in order to guarantee the necessary spatial accuracy to the process of images exterior

  4. Natural Resource Information System. Volume 2: System operating procedures and instructions

    Science.gov (United States)

    1972-01-01

    A total computer software system description is provided for the prototype Natural Resource Information System designed to store, process, and display data of maximum usefulness to land management decision making. Program modules are described, as are the computer file design, file updating methods, digitizing process, and paper tape conversion to magnetic tape. Operating instructions for the system, data output, printed output, and graphic output are also discussed.

  5. A discontinuous Galerkin method on kinetic flocking models

    OpenAIRE

    Tan, Changhui

    2014-01-01

    We study kinetic representations of flocking models. They arise from agent-based models for self-organized dynamics, such as Cucker-Smale and Motsch-Tadmor models. We prove flocking behavior for the kinetic descriptions of flocking systems, which indicates a concentration in velocity variable in infinite time. We propose a discontinuous Galerkin method to treat the asymptotic $\\delta$-singularity, and construct high order positive preserving scheme to solve kinetic flocking systems.

  6. Terrestrial ecological systems and natural communities of Nebraska

    Data.gov (United States)

    Department of the Interior — Over two decades ago, The Nature Conservancy (TNC) and state natural heritage programs developed the “coarse filter/fine filter” approach to preserving biological...

  7. Derivative discontinuity with localized Hartree-Fock potential.

    Science.gov (United States)

    Nazarov, V U; Vignale, G

    2015-08-14

    The localized Hartree-Fock potential has proven to be a computationally efficient alternative to the optimized effective potential, preserving the numerical accuracy of the latter and respecting the exact properties of being self-interaction free and having the correct -1/r asymptotics. In this paper we extend the localized Hartree-Fock potential to fractional particle numbers and observe that it yields derivative discontinuities in the energy as required by the exact theory. The discontinuities are numerically close to those of the computationally more demanding Hartree-Fock method. Our potential enjoys a "direct-energy" property, whereby the energy of the system is given by the sum of the single-particle eigenvalues multiplied by the corresponding occupation numbers. The discontinuities c↑ and c↓ of the spin-components of the potential at integer particle numbers N↑ and N↓ satisfy the condition c↑N↑ + c↓N↓ = 0. Thus, joining the family of effective potentials which support a derivative discontinuity, but being considerably easier to implement, the localized Hartree-Fock potential becomes a powerful tool in the broad area of applications in which the fundamental gap is an issue.

  8. Politics of Natural Resource Management and Accountable Systems ...

    African Journals Online (AJOL)

    The political behaviour of public institutions exhibited in the management of critical natural resources influences the nature of service delivery. In particular, the character of such public organizations as regulators of natural resources, like water, impacts not only on what such management bodies do and their functionality, ...

  9. High Altitude Aerial Natural Gas Leak Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Richard T. Wainner; Mickey B. Frish; B. David Green; Matthew C. Laderer; Mark G. Allen; Joseph R. Morency

    2006-12-31

    The objective of this program was to develop and demonstrate a cost-effective and power-efficient advanced standoff sensing technology able to detect and quantify, from a high-altitude (> 10,000 ft) aircraft, natural gas leaking from a high-pressure pipeline. The advanced technology is based on an enhanced version of the Remote Methane Leak Detector (RMLD) platform developed previously by Physical Sciences Inc. (PSI). The RMLD combines a telecommunications-style diode laser, fiber-optic components, and low-cost DSP electronics with the well-understood principles of Wavelength Modulation Spectroscopy (WMS), to indicate the presence of natural gas located between the operator and a topographic target. The transceiver transmits a laser beam onto a topographic target and receives some of the laser light reflected by the target. The controller processes the received light signal to deduce the amount of methane in the laser's path. For use in the airborne platform, we modified three aspects of the RMLD, by: (1) inserting an Erbium-doped optical fiber laser amplifier to increase the transmitted laser power from 10 mW to 5W; (2) increasing the optical receiver diameter from 10 cm to 25 cm; and (3) altering the laser wavelength from 1653 nm to 1618 nm. The modified RMLD system provides a path-integrated methane concentration sensitivity {approx}5000 ppm-m, sufficient to detect the presence of a leak from a high capacity transmission line while discriminating against attenuation by ambient methane. In ground-based simulations of the aerial leak detection scenario, we demonstrated the ability to measure methane leaks within the laser beam path when it illuminates a topographic target 2000 m away. We also demonstrated simulated leak detection from ranges of 200 m using the 25 cm optical receiver without the fiber amplifier.

  10. Logistical management system for natural gas distribution; Sistema de gestao logistica para a distribuicao de gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Arruda, Joao Bosco F.; Nobre Junior, Ernesto F.; Praca, Eduardo R. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Nucleo de Pesquisa em Logistica, Transportes e Desenvolvimento

    2004-07-01

    The Brazilian Federal Government has the very purpose of increasing the participation of the Natural Gas in the primary energy internal supply from 7,5% nowadays to about 12% till 2010. However, for that, it is necessary to eliminate the great impedance represented by the restricted accessibility to the product, due to the high distribution costs involved. So, there is an urgent need for availability of technologies to help natural gas distribution systems. This paper proposes an innovative logistics-based approach on the subject of the natural gas distribution, through a computational tool (GASLOG System) to be applied in the North and Northeastern urban and country areas of Brazil, with initial case study in the city of Fortaleza. In its conception, the GASLOG System focuses on the point-of-view of everyone of the actors involved with the natural gas distribution process trying to respond their particular necessities in the sector. (author)

  11. Interactions in Natural Colloid Systems "Biosolids" - Soil and Plant

    Science.gov (United States)

    Kalinichenko, Kira V.; Nikovskaya, Galina N.; Ulberg, Zoya R.

    2016-04-01

    The "biosolids" are complex biocolloid system arising in huge amounts (mln tons per year) from biological municipal wastewater treatment. These contain clusters of nanoparticles of heavy metal compounds (in slightly soluble or unsoluble forms, such as phosphates, sulphates, carbonates, hydroxides, and etc.), cells, humic substances and so on, involved in exopolysaccharides (EPS) net matrix. One may consider that biosolids are the natural nanocomposite. Due to the presence of nitrogen, phosphorus, potassium and other macro- and microelements (heavy metals), vitamins, aminoacids, etc., the biosolids are a depot of bioelements for plant nutrition. Thus, it is generally recognized that most rationally to utilize them for land application. For this purpose the biocolloid process was developed in biosolids system by initiation of microbial vital ability followed by the synthesis of EPS, propagation of ecologically important microorganisms, loosening of the structure and weakening of the coagulation contacts between biosolids colloids, but the structure integrity maintaining [1,2]. It was demonstrated that the applying of biosolids with metabolizing microorganisms to soil provided the improving soil structure, namely the increasing of waterstable aggregates content (70% vs. 20%). It occurs due to flocculation ability of biosolids EPS. The experimental modelling of mutual interactions in systems of soils - biosolids (with metabolizing microorganisms) were realized and their colloid and chemical mechanisms were formulated [3]. As it is known, the most harmonious plant growth comes at a prolonged entering of nutrients under the action of plant roots exudates which include pool of organic acids and polysaccharides [4]. Special investigations showed that under the influence of exudates excreted by growing plants, the biosolids microelements can release gradually from immobilized state into environment and are able to absorb by plants. Thus, the biosolids can serve as an active

  12. Discontinuity Detection for Analysis of Telerobot Trajectories

    Science.gov (United States)

    Yeom, Kiwon; Ellis, Stephen R.; Adelstein, Bernard D.

    2013-01-01

    To identify spatial and temporal discontinuities in telerobot movement in order to describe the shift in operators control and error correction strategies from continuous control to move-and-wait strategies. This shift was studied under conditions of simulated increasingly time-delayed teleoperation. The ultimate goal is to determine if the time delay associated with the shift is invariant with independently imposed control difficulty. We expect this shift to manifest itself as changes in the number of discontinuity of movement path. We proposed an approach to spatial and temporal discontinuity detection algorithm for analysis of teleoperated trajectory in three dimensional space. The algorithm provides a simple and potentially objective method for detecting the discontinuity during telerobot operation and evaluating the difficulty of rotational coordinate condition in teleoperation.

  13. Discontinuous Galerkin for the Radiative Transport Equation

    KAUST Repository

    Guermond, Jean-Luc

    2013-10-11

    This note presents some recent results regarding the approximation of the linear radiative transfer equation using discontinuous Galerkin methods. The locking effect occurring in the diffusion limit with the upwind numerical flux is investigated and a correction technique is proposed.

  14. Discontinuance of ADHD Treatment in Adolescents

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-04-01

    Full Text Available Prevalence of ADHD drug discontinuance in adolescents and young adults was studied in the UK by using the General Practice Database for patients aged 15-21 years from 1999 to 2006.

  15. 76 FR 22825 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems

    Science.gov (United States)

    2011-04-25

    ... AGENCY 40 CFR Parts 98 Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems AGENCY..., 2010 EPA promulgated Subpart W: Petroleum and Natural Gas Systems of the Greenhouse Gas Reporting Rule... outlined for calculating greenhouse gas emissions for the petroleum and natural gas systems source category...

  16. Discontinuous Galerkin algorithms for fully kinetic plasmas

    Science.gov (United States)

    Juno, J.; Hakim, A.; TenBarge, J.; Shi, E.; Dorland, W.

    2018-01-01

    We present a new algorithm for the discretization of the non-relativistic Vlasov-Maxwell system of equations for the study of plasmas in the kinetic regime. Using the discontinuous Galerkin finite element method for the spatial discretization, we obtain a high order accurate solution for the plasma's distribution function. Time stepping for the distribution function is done explicitly with a third order strong-stability preserving Runge-Kutta method. Since the Vlasov equation in the Vlasov-Maxwell system is a high dimensional transport equation, up to six dimensions plus time, we take special care to note various features we have implemented to reduce the cost while maintaining the integrity of the solution, including the use of a reduced high-order basis set. A series of benchmarks, from simple wave and shock calculations, to a five dimensional turbulence simulation, are presented to verify the efficacy of our set of numerical methods, as well as demonstrate the power of the implemented features.

  17. FABRIC TENSOR FOR DISCONTINUOUS GEOLOGICAL MATERIALS

    OpenAIRE

    小田, 匡寛

    1982-01-01

    Geometrical property (fabric) of discontinuity in geological materials is discussed in terms of (1) position and density, (2) shape and dimension and (3) orientation of related discontinuities such as joint, fault and discrete particle. By taking into account these geometrical elements, a unique measure called fabric tensor F_ is definitely introduced to embody the fabric concept without loss of generality.The first invariant of F_ is important as an index measure to evaluate the crack intens...

  18. Area Regge calculus and discontinuous metrics

    International Nuclear Information System (INIS)

    Wainwright, Chris; Williams, Ruth M

    2004-01-01

    Taking the triangle areas as independent variables in the theory of Regge calculus can lead to ambiguities in the edge lengths, which can be interpreted as discontinuities in the metric. We construct solutions to area Regge calculus using a triangulated lattice and find that on a spacelike or timelike hypersurface no such discontinuity can arise. On a null hypersurface however, we can have such a situation and the resulting metric can be interpreted as a so-called refractive wave

  19. Cultivo da levedura Phaffia rhodozyma (Xanthophyllomyces dendrorhous em processo descontínuo alimentado para produção de astaxantina Cultivation of Phaffia rhodozyma (Xanthophyllomyces dendrorhous yeast in discontinuous system to obtain astaxanthin

    Directory of Open Access Journals (Sweden)

    Miriam Blümel Chociai

    2002-12-01

    Full Text Available A levedura Phaffia rhodozyma, produtora de astaxantina, pigmento carotenóide largamente empregado na aqüicultura de peixes e crustáceos, pode ser eficientemente cultivada num meio de cultura de baixo custo, à base de caldo de cana diluído 1:10 e uréia a 1 g/L. No entanto, a produção de biomassa e a formação do carotenóide sofrem a inibição pelo substrato (efeito "Crabtree", limitando desta forma a utilização do caldo de cana com concentrações da fonte de carbono superiores a 20 g/L, importante consideração na produção industrial de astaxantina. No presente trabalho, o cultivo da levedura P. rhodozyma foi realizado em processo descontínuo alimentado, no qual se obteve produtividade volumétrica de 0,024 mg astaxantina/L.h. em relação aos 0,013 mg astaxantina/L.h. obtidos no cultivo controle, que não sofreu alimentação da fonte de carbono.The yeast Phaffia rhodozyma produces astaxanthin, a carotenoid pigment widely applied in fish and crustaceous cultivation. This yeast can be efficiently cultured in a low cost medium, sugar cane broth diluted 1:10 and supplemented with 1 g/L urea. However, the biomass and astaxanthin production undergo inhibition by the substrate (Crabtree effect, limiting the utilization of sugar cane broth up to 20 g/L total sugar concentration. Therefore, this effect must be considered during the industrial production of astaxanthin. In the present work, using fed batch system to cultivate P. rhodozyma we were able to obtain 0.024 mg astaxanthin/l.h compared to 0.013 mg astaxanthin/l.h obtained by the discontinuous cultivation system.

  20. A gradient estimate for solutions to parabolic equations with discontinuous coefficients

    Directory of Open Access Journals (Sweden)

    Jishan Fan

    2013-04-01

    Full Text Available Li-Vogelius and Li-Nirenberg gave a gradient estimate for solutions of strongly elliptic equations and systems of divergence forms with piecewise smooth coefficients, respectively. The discontinuities of the coefficients are assumed to be given by manifolds of codimension 1, which we called them emph{manifolds of discontinuities}. Their gradient estimate is independent of the distances between manifolds of discontinuities. In this paper, we gave a parabolic version of their results. That is, we gave a gradient estimate for parabolic equations of divergence forms with piecewise smooth coefficients. The coefficients are assumed to be independent of time and their discontinuities are likewise the previous elliptic equations. As an application of this estimate, we also gave a pointwise gradient estimate for the fundamental solution of a parabolic operator with piecewise smooth coefficients. Both gradient estimates are independent of the distances between manifolds of discontinuities.

  1. natural

    Directory of Open Access Journals (Sweden)

    Elías Gómez Macías

    2006-01-01

    Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.

  2. Biochar as enhancement material in natural attenuation systems

    Science.gov (United States)

    Kirmizakis, P.; Doherty, R.; Mendonça, C. A.; Costeira, R.; Allen, C.; Kulakov, L.

    2017-12-01

    Bioelectrochemical systems (BESs) have gained increasingly popularity over the last years especially in monitoring and clean-up of contaminants. BES are systems that combine wastewater treatment with energy production and resource recovery by harness the electro-activity of microorganisms. BESs consist of two electrodes, an anode and a cathode, separated with a proton-exchange membrane and an external electrical circuit which permits the passage of electrons generated at the anode to the cathode. Here we present a speed up of this natural breakdown process by providing a place to capture the anaerobic contaminants onto Biochar which captures the contaminants and also acts like a high surface area electrode passing electrons to the aerobic environments. For the purpose of this project, identical graphite and Teflon cells were constructed to compare and determine whether a Biochar BES was more efficient than a standard BES and more efficient than Biochar as sorption agent. Current production monitoring used as a real-time view of the process. The Biochar BES out performed both the BES and the Biochar BES in reduction of contaminants across the board. Our results suggest that the maximum growth and electro-activity of the microbial community occurred in the Biochar BES. This is in agreement with microbial findings which suggests that Biochar BES has a less diverse population which is more focused towards degradation and electroactive activity. For further understanding of the results, further geochemical analysis performed to provide additional insight on the process. This works shows clearly the applicability and efficiency of biochar among other electrode and sorption materials and electrical monitoring is versatile experimental tool to the remediation process and can be used as a non-destructive way to indirectly reveal process leading in understanding basic fundamental physical behaviours under specific experimental conditions.

  3. A counter system for natural C14 measurement

    International Nuclear Information System (INIS)

    Oona, H.; Fan, C.Y.

    1977-01-01

    Two proportional counters made of plastic scintillator were constructed for measuring the C14 contents in dated tree rings. One is for background and the other for specimen. CH 4 at 1 atm pressure was used as the counter gas; each counter has an active volume approximately 5.5 l. The wall, being a scintillator, serves as a 4π anti-coincidence shell for rejection of natural radioactivity in the material housing the proportional counter and penetrating cosmic ray muons. The outputs of the proportional counters which are in anticoincidence with the scintillation counter were recorded in a pulse height analyzer. After background subtraction, it yields the beta-decay spectrum of carbon-14 in the methane filled proportional counter. Simultaneously, the outputs which are in coincidence with the scintillation counter were also recorded as a monitor of the operational characteristics of the detector systems. The problems inherent with pulse height analyzers and the use of scintillators are discussed and evaluated. (Auth.)

  4. Virtual Pipeline System Testbed to Optimize the U.S. Natural Gas Transmission Pipeline System

    Energy Technology Data Exchange (ETDEWEB)

    Kirby S. Chapman; Prakash Krishniswami; Virg Wallentine; Mohammed Abbaspour; Revathi Ranganathan; Ravi Addanki; Jeet Sengupta; Liubo Chen

    2005-06-01

    The goal of this project is to develop a Virtual Pipeline System Testbed (VPST) for natural gas transmission. This study uses a fully implicit finite difference method to analyze transient, nonisothermal compressible gas flow through a gas pipeline system. The inertia term of the momentum equation is included in the analysis. The testbed simulate compressor stations, the pipe that connects these compressor stations, the supply sources, and the end-user demand markets. The compressor station is described by identifying the make, model, and number of engines, gas turbines, and compressors. System operators and engineers can analyze the impact of system changes on the dynamic deliverability of gas and on the environment.

  5. Natural frequency extraction of a beam-moving mass system with periodic passages using its pseudo-natural frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Ghorbani, Esmaeil; Keshmiri, Mehdi [Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2016-07-15

    Wind turbines, helicopters, and turbo-machineries' rotary motion, along with a variety of nonlinear structures linearized with their periodic limit cycles, may all contain time-periodic terms in their equations of motion even if the equations remain linear. The purpose of this study is to model these systems into a beam-moving mass system. Natural frequencies of the beam are calculated using past work in which pseudo-natural frequencies of a beam-moving mass system were extracted, followed by the homotopy perturbation method. The findings of this study are valuable to the industry, and they decrease error margin in resonance range assessment. This approach indicates that for beam-moving mass systems, extraction of natural frequencies that ignore the moving mass effect can lead to inaccurate results, whereas only a limited amount of physical data are needed obtain accurate calculations. Furthermore, this study used homotopy perturbation for operational modal analysis purposes and not for solving nonlinear equations.

  6. Multi-slicing strategy for the three-dimensional discontinuity layout optimization (3D DLO).

    Science.gov (United States)

    Zhang, Yiming

    2017-03-01

    Discontinuity layout optimization (DLO) is a recently presented topology optimization method for determining the critical layout of discontinuities and the associated upper bound limit load for plane two-dimensional and three-dimensional (3D) problems. The modelling process (pre-processing) for DLO includes defining the discontinuities inside a specified domain and building the target function and the global constraint matrix for the optimization solver, which has great influence on the the efficiency of the computation processes and the reliability of the final results. This paper focuses on efficient and reliable pre-processing of the discontinuities within the 3D DLO and presents a multi-slicing strategy, which naturally avoids the overlapping and crossing of different discontinuities. Furthermore, the formulation of the 3D discontinuity considering a shape of an arbitrary convex polygon is introduced, permitting the efficient assembly of the global constraint matrix. The proposed method eliminates unnecessary discontinuities in 3D DLO, making it possible to apply 3D DLO for solving large-scale engineering problems such as those involving landslides. Numerical examples including a footing test, a 3D landslide and a punch indentation are considered, illustrating the effectiveness of the presented method. © 2016 The Authors. International Journal for Numerical and Analytical Methods in Geomechanics published by John Wiley & Sons Ltd.

  7. Convergent High-Order Compact WENO Discontinuity Capturing with Positivity Preserving for Unstructured Discontinuous Galerkin Schemes

    Data.gov (United States)

    National Aeronautics and Space Administration — Challenges: Our recent investigation revealed that the more advanced discontinuity capturing weighted essentially nonoscillatory (WENO) technique, which is of...

  8. Finite element and discontinuous Galerkin methods for transient wave equations

    CERN Document Server

    Cohen, Gary

    2017-01-01

    This monograph presents numerical methods for solving transient wave equations (i.e. in time domain). More precisely, it provides an overview of continuous and discontinuous finite element methods for these equations, including their implementation in physical models, an extensive description of 2D and 3D elements with different shapes, such as prisms or pyramids, an analysis of the accuracy of the methods and the study of the Maxwell’s system and the important problem of its spurious free approximations. After recalling the classical models, i.e. acoustics, linear elastodynamics and electromagnetism and their variational formulations, the authors present a wide variety of finite elements of different shapes useful for the numerical resolution of wave equations. Then, they focus on the construction of efficient continuous and discontinuous Galerkin methods and study their accuracy by plane wave techniques and a priori error estimates. A chapter is devoted to the Maxwell’s system and the important problem ...

  9. Generic Natural Systems Evaluation - Thermodynamic Database Development and Data Management

    International Nuclear Information System (INIS)

    Wolery, T.W.; Sutton, M.

    2011-01-01

    Thermodynamic data are essential for understanding and evaluating geochemical processes, as by speciation-solubility calculations, reaction-path modeling, or reactive transport simulation. These data are required to evaluate both equilibrium states and the kinetic approach to such states (via the affinity term or its equivalent in commonly used rate laws). These types of calculations and the data needed to carry them out are a central feature of geochemistry in many applications, including water-rock interactions in natural systems at low and high temperatures. Such calculations are also made in engineering studies, for example studies of interactions involving man-made materials such as metal alloys and concrete. They are used in a fairly broad spectrum of repository studies where interactions take place among water, rock, and man-made materials (e.g., usage on YMP and WIPP). Waste form degradation, engineered barrier system performance, and near-field and far-field transport typically incorporate some level of thermodynamic modeling, requiring the relevant supporting data. Typical applications of thermodynamic modeling involve calculations of aqueous speciation (which is of great importance in the case of most radionuclides), solubilities of minerals and related solids, solubilities of gases, and stability relations among the various possible phases that might be present in a chemical system at a given temperature and pressure. If a phase can have a variable chemical composition, then a common calculational task is to determine that composition. Thermodynamic modeling also encompasses ion exchange and surface complexation processes. Any and all of these processes may be important in a geochemical process or reactive transport calculation. Such calculations are generally carried out using computer codes. For geochemical modeling calculations, codes such as EQ3/6 and PHREEQC, are commonly used. These codes typically provide 'full service' geochemistry, meaning that

  10. Generic Natural Systems Evaluation - Thermodynamic Database Development and Data Management

    Energy Technology Data Exchange (ETDEWEB)

    Wolery, T W; Sutton, M

    2011-09-19

    Thermodynamic data are essential for understanding and evaluating geochemical processes, as by speciation-solubility calculations, reaction-path modeling, or reactive transport simulation. These data are required to evaluate both equilibrium states and the kinetic approach to such states (via the affinity term or its equivalent in commonly used rate laws). These types of calculations and the data needed to carry them out are a central feature of geochemistry in many applications, including water-rock interactions in natural systems at low and high temperatures. Such calculations are also made in engineering studies, for example studies of interactions involving man-made materials such as metal alloys and concrete. They are used in a fairly broad spectrum of repository studies where interactions take place among water, rock, and man-made materials (e.g., usage on YMP and WIPP). Waste form degradation, engineered barrier system performance, and near-field and far-field transport typically incorporate some level of thermodynamic modeling, requiring the relevant supporting data. Typical applications of thermodynamic modeling involve calculations of aqueous speciation (which is of great importance in the case of most radionuclides), solubilities of minerals and related solids, solubilities of gases, and stability relations among the various possible phases that might be present in a chemical system at a given temperature and pressure. If a phase can have a variable chemical composition, then a common calculational task is to determine that composition. Thermodynamic modeling also encompasses ion exchange and surface complexation processes. Any and all of these processes may be important in a geochemical process or reactive transport calculation. Such calculations are generally carried out using computer codes. For geochemical modeling calculations, codes such as EQ3/6 and PHREEQC, are commonly used. These codes typically provide 'full service' geochemistry

  11. Transition strategies for managing technological discontinuities: lessons from the history of the semiconductor industry

    NARCIS (Netherlands)

    Stoelhorst, J.W.

    2002-01-01

    This paper explores the nature of competition under conditions of technological change and asks how firms can manage technological discontinuities. By drawing on the literatures on strategic management and technology dynamics, it is proposed that firms should change the nature of their strategy as a

  12. Silver nanoparticles delivery system based on natural rubber latex membranes

    Energy Technology Data Exchange (ETDEWEB)

    Guidelli, Eder Jose, E-mail: ederguidelli@gmail.com [Universidade de Sao Paulo/FFCLRP-DF (Brazil); Kinoshita, Angela [Universidade do Sagrado Coracao (Brazil); Ramos, Ana Paula [Universidade de Sao Paulo/FFCLRP-DQ (Brazil); Baffa, Oswaldo [Universidade de Sao Paulo/FFCLRP-DF (Brazil)

    2013-04-15

    The search for new materials for biomedical applications is extremely important. Here, we present results on the performance of a silver nanoparticles delivery system using natural rubber latex (NRL) as the polymeric matrix. Our aim was to obtain an optimized wound dressing by combining materials with potential healing action. The synthesis of silver nanoparticles and their characterization by UV-Vis spectroscopy, transmission electron microscopy, zeta potential, dynamic light scattering, and Fourier transform infrared spectroscopy (FTIR) are depicted. The NRL membranes are good matrix for silver nanoparticles and allow for their gradual release. The release of 30 nm silver nanoparticles by the NRL membranes depends on their mass percentage in NRL membranes. The total concentration of AgNP released by the NRL membranes was calculated. The AgNP attached to the cis-isoprene molecules in the NRL matrix remain attached to the membrane ({approx}0.1 % w/w). So, only the AgNP bound to the non-rubber molecules are released. FTIR spectra suggest that non-rubber molecules, like aminoacids and proteins, associated with the serum fraction of the NRL may be attached to the surfaces of the released nanoparticles, thereby increasing the release of such molecules. The released silver nanoparticles are sterically stabilized, more stable and well dispersed. Because the serum fraction of the NRL is responsible for the angiogenic properties of the matrix, the silver nanoparticles could increment the angiogenic properties of NRL. This biomaterial has desirable properties for the fabrication of a wound dressing with potential healing action, since it combines the angiogenic and antibacterial properties of the silver nanoparticles with the increased angiogenic properties of the NRL.Graphical AbstractThe AgNP attached to the cis-isoprene molecules remain in the NRL matrix and only the AgNP bound to the non-rubber molecules (NRL serum fraction) are released. The released AgNP are

  13. Silver nanoparticles delivery system based on natural rubber latex membranes

    Science.gov (United States)

    Guidelli, Éder José; Kinoshita, Angela; Ramos, Ana Paula; Baffa, Oswaldo

    2013-04-01

    The search for new materials for biomedical applications is extremely important. Here, we present results on the performance of a silver nanoparticles delivery system using natural rubber latex (NRL) as the polymeric matrix. Our aim was to obtain an optimized wound dressing by combining materials with potential healing action. The synthesis of silver nanoparticles and their characterization by UV-Vis spectroscopy, transmission electron microscopy, zeta potential, dynamic light scattering, and Fourier transform infrared spectroscopy (FTIR) are depicted. The NRL membranes are good matrix for silver nanoparticles and allow for their gradual release. The release of 30 nm silver nanoparticles by the NRL membranes depends on their mass percentage in NRL membranes. The total concentration of AgNP released by the NRL membranes was calculated. The AgNP attached to the cis-isoprene molecules in the NRL matrix remain attached to the membrane ( 0.1 % w/w). So, only the AgNP bound to the non-rubber molecules are released. FTIR spectra suggest that non-rubber molecules, like aminoacids and proteins, associated with the serum fraction of the NRL may be attached to the surfaces of the released nanoparticles, thereby increasing the release of such molecules. The released silver nanoparticles are sterically stabilized, more stable and well dispersed. Because the serum fraction of the NRL is responsible for the angiogenic properties of the matrix, the silver nanoparticles could increment the angiogenic properties of NRL. This biomaterial has desirable properties for the fabrication of a wound dressing with potential healing action, since it combines the angiogenic and antibacterial properties of the silver nanoparticles with the increased angiogenic properties of the NRL.

  14. Weather impacts on natural, social and economic systems. German report

    Energy Technology Data Exchange (ETDEWEB)

    Flechsig, M.; Gerlinger, K.; Herrmann, N.; Klein, R.J.T.; Schneider, M.; Sterr, H.; Schellnhuber, H.J.

    2000-05-01

    The EU project Weather Impacts on Natural, Social and Economic Systems (WISE) has analysed impacts of current climate variability to evaluate the sensitivity of today's society to extreme weather. Unlike studies of anticipated impacts of climate change, WISE did not rely on scenarios and projections, but on existing and newly collected data. The research involved (i) the statistical modelling of meteorological and sectoral time series, aimed at quantifying the impacts of changing weather variables on sector output, (ii) a population survey, aimed at investigating public perception of and behavioural response to unusually hot and dry summers and mild winters, and (iii) a management survey, aimed at obtaining insight into managers' awareness and perception of the importance of extreme weather on their operations. The three activities revealed a wealth of data and information, providing relevant insights into Germany's sensitivity to and perception of extreme weather events. Sectors that were analysed included agriculture, outdoor fire, water supply, human health, electricity and gas consumption and tourism. It appears from the statistical modelling that extreme weather can have impressive impacts on all sectors, especially when expressed in monetary terms. However, weather variability is generally considered a manageable risk, to which sectors in Germany appear reasonably well-adapted. The population and management surveys reveal both positive and negative impacts of extreme weather. People generally respond to these impacts by adjusting their activities. The utilities (electricity, gas and water) indicate that they are robsut to the current level of weather variability and do not consider climate change an important threat to their operations. The tourism sector experiences impacts but typically takes a reactive approach to adaptation, although it is also developing weather-insensitive products. (orig.)

  15. Discontinuation Decision in Assisted Reproductive Techniques

    Directory of Open Access Journals (Sweden)

    Ashraf Moini

    2009-01-01

    Full Text Available Background: In vitro fertilization (IVF and intra cytoplasmic sperm injection (ICSI are recognizedas established and increasingly successful forms of treatment for infertility, yet significant numbersof couples discontinue treatment without achieving a live birth. This study aims to identify majorfactors that influence the decision to discontinue IVF/ICSI treatments.Materials and Methods: We studied the data of 338 couples who discontinued their infertilitytreatments after three cycles; based on medical records and phone contact. The main measure wasthe reason for stopping their treatments.Results: Economical problems were cited by 212 couples (62.7%, as their mean income wassignificantly less than other couples (p<0.0001. Lack of success was reported as a reason by229 (67.8%, from whom 165 (72% also had economical problems. Achieving independent-ART pregnancy was the reason for discontinuation in 20 (5.9% couples. Psychological stress,depression and anxiety were reported as other cessation factors by 169 (50%, 148 (43.8% and 182(53.8% couples, respectively.Conclusion: This survey suggests that the most common reasons for assisted reproductivetechnique (ART discontinuation after three cycles are: prior unsuccessful cycles, economicaland psychological problems. Therefore, the substantial proportion of couples could benefit frompsychological intervention, increasing awareness of ART outcomes and health funding to copemore adequately with failed treatments.

  16. 27 CFR 478.127 - Discontinuance of business.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Discontinuance of business... Records § 478.127 Discontinuance of business. Where a licensed business is discontinued and succeeded by a... be delivered to the successor. Where discontinuance of the business is absolute, the records shall be...

  17. 27 CFR 555.128 - Discontinuance of business.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Discontinuance of business... Discontinuance of business. Where an explosive materials business or operations is discontinued and succeeded by... such facts and shall be delivered to the successor. Where discontinuance of the business or operations...

  18. 27 CFR 478.57 - Discontinuance of business.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Discontinuance of business... Licenses § 478.57 Discontinuance of business. (a) Where a firearm or ammunition business is either discontinued or succeeded by a new owner, the owner of the business discontinued or succeeded shall within 30...

  19. The Enigmatic but Unique Nature of the Israeli Legal System ...

    African Journals Online (AJOL)

    In this respect, Israel may have contributed much to the reinvigoration of the modern comparative law agenda, and it may continue to do so in the future, as the system is not one of legal stasis (a mixed system) but one of legal kinesis (a mixing system). Keywords: Israeli legal system, Israeli Supreme Court, legal systemics, ...

  20. On the discontinuous nature of the Mozambique Current

    Directory of Open Access Journals (Sweden)

    Wilhelmus P.M. de Ruijter

    2012-01-01

    Full Text Available The concept of a spatially continuous western boundary current in the Mozambique Channel has historically been based on erroneous interpretations of ships’ drift. Recent observations have demonstrated that the circulation in the Channel is instead dominated by anti-cyclonic eddies drifting poleward. It has therefore been suggested that no coherent Mozambique Current exists at any time. However, satellite and other observations indicate that a continuous current – not necessarily an inherent part of Mozambique Eddies – may at times be found along the full Mozambican shelf break. Using a high-resolution, numerical model we have demonstrated how such a feature may come about. In the model, a continuous current is a highly irregularly occurring event, occurring about once per year, with an average duration of only 9 days and with a vertical extent of about 800 m. Surface speeds may vary from 0.5 m/s to 1.5 m/s and the volume flux involved is about 10 Sv. The continuous current may occasionally be important for the transport of biota along the continental shelf and slope.

  1. On the discontinuous nature of the Mozambique Current

    NARCIS (Netherlands)

    Lutjeharms, J.R.E.; Biastoch, A.; van der Werf, P.M.; Ridderinkhof, H.; de Ruijter, W.P.M.

    2012-01-01

    The concept of a spatially continuous western boundary current in the Mozambique Channel has historically been based on erroneous interpretations of ships' drift. Recent observations have demonstrated that the circulation in the Channel is instead dominated by anti-cyclonic eddies drifting poleward.

  2. Localization in Naturally Deformed Systems - the Default State?

    Science.gov (United States)

    Clancy White, Joseph

    2017-04-01

    Based on the extensive literature on localized rock deformation, conventional wisdom would interpret it to be a special behaviour within an anticipated background of otherwise uniform deformation. The latter notwithstanding, the rock record is so rife with transient (cyclic), heterogeneous deformation, notably shear localization, as to characterize localization as the anticipated 'normal' behaviour. The corollary is that steady, homogeneous deformation is significantly less common, and if achieved must reflect some special set of conditions that are not representative of the general case. An issue central to natural deformation is then not the existance of localized strain, but rather how the extant deformation processes scale across tectonic phenomena and in turn organize to enable a coherent(?) descripion of Earth deformation. Deformation is fundamentally quantized, discrete (diffusion, glide, crack propagation) and reliant on the defect state of rock-forming minerals. The strain energy distribution that drives thermo-mechanical responses is in the first instance established at the grain-scale where the non-linear interaction of defect-mediated micromechanical processes introduces heterogeneous behaviour described by various gradient theories, and evidenced by the defect microstructures of deformed rocks. Hence, the potential for non-uniform response is embedded within even quasi-uniform, monomineralic materials, seen, for example, in the spatially discrete evolution of dynamic recrystallization. What passes as homogeneous or uniform deformation at various scales is the aggregation of responses at some characteristic dimension at which heterogeneity is not registered or measured. Nevertheless, the aggregate response and associated normalized parameters (strain, strain rate) do not correspond to any condition actually experienced by the deforming material. The more common types of macroscopic heterogeneity promoting localization comprise mechanically contrasting

  3. The Nature and Assessment of Systemic Risk in Terms of Liquidity of the Banking System

    Directory of Open Access Journals (Sweden)

    Lavreniuk Vladyslav V.

    2016-11-01

    Full Text Available The aim of the article is to determine the nature of systemic risk as a threat to the financial stability of the banking system and develop analytical tools to assess its impact on the banking system in terms of its liquidity. To solve the tasks assigned, there used general scientific and specific methods, such as: logical and dialectical method, mathematical and graphical one. Based on the generalization, analysis and comparison of different interpretations, there clarified the concept of «systemic risk» as a risk generated by financial institutions or individual sectors through the implementation of the mechanism of risk transmission, achieving significant scale of distribution and adversely affecting the stability of the financial system and the real sector of economy. There identified key aspects of systemic risk: a systemic risk is not a sum of all individual risks of financial institutions; b spreads through the channels of interconnectedness between financial institutions; c is a result of accumulated structural imbalances; d affects the stability of the financial/banking system, public confidence and the real sector of economy. Analytical tools for estimation of the bank’s contribution to the systemic liquidity risk on the basis of which it is determined that the first place in terms of the effect on the aggregate systemic risk of liquidity of the Ukrainian banking system is occupied by banks of Group I, the second place — by Privatbank, the third, fourth, fifth places — by banks in Group II — Oschadbank, Ukreximbank. It is found that it is systemically important state-owned banks that have a significant impact on systemic liquidity risk. It is determined that the probability of default of a leading systemically important bank could result in considerable cumulative losses for the entire banking system and real economy. The prospects of further research are the development of tools for systemic risk assessment with respect to

  4. Theory and observation of double discontinuities

    Directory of Open Access Journals (Sweden)

    Y. C. Whang

    2004-01-01

    Full Text Available Recent research using high-resolution magnetic field data to examine the interior structures of MHD shocks in interplanetary space and in the magnetotail led to a surprising discovery that a slow-mode shock is often followed by an adjoining rotational discontinuity layer on the postshock side. The thickness of each layer is of the order of a few ion inertial lengths. Such a compound structure is known as a double discontinuity. When the magnetic field rotates by several degrees per ion inertial length inside a thin layer, the Hall current term becomes important in the generalized Ohm's law. Steady state solutions based on the Hall-MHD theory have been obtained to show the merging of a rotational layer and a slow shock layer to form a compound structure like the observed double discontinuities.

  5. Systems metabolic engineering of microorganisms for natural and non-natural chemicals.

    Science.gov (United States)

    Lee, Jeong Wook; Na, Dokyun; Park, Jong Myoung; Lee, Joungmin; Choi, Sol; Lee, Sang Yup

    2012-05-17

    Growing concerns over limited fossil resources and associated environmental problems are motivating the development of sustainable processes for the production of chemicals, fuels and materials from renewable resources. Metabolic engineering is a key enabling technology for transforming microorganisms into efficient cell factories for these compounds. Systems metabolic engineering, which incorporates the concepts and techniques of systems biology, synthetic biology and evolutionary engineering at the systems level, offers a conceptual and technological framework to speed the creation of new metabolic enzymes and pathways or the modification of existing pathways for the optimal production of desired products. Here we discuss the general strategies of systems metabolic engineering and examples of its application and offer insights as to when and how each of the different strategies should be used. Finally, we highlight the limitations and challenges to be overcome for the systems metabolic engineering of microorganisms at more advanced levels.

  6. A decision support system for rebase location in a nature ...

    African Journals Online (AJOL)

    It is important that rebases are available on standby at strategic locations in a nature conservation area from where wildre ignition points can be reached rapidly and such res brought under control before they spread. Two facility location models are proposed in this paper which may form the basis for decision support when ...

  7. Emergency Message Dissemination System for Smartphones During Natural Disasters

    NARCIS (Netherlands)

    Wu, Xian; Mazurowski, Maciej; Chen, Zhen; Meratnia, Nirvana

    This paper revolves around the concept of utilizing the modern smartphone communication capabilities to transmit messages through an ad hoc network during a disaster, which renders the traditional cellular base station inaccessible. Due to dynamic and decentralized nature of the considered

  8. Artificial intelligence system for the monitoring of natural gas production systems; Intelligente Ueberwachung von Erdgasfoerderanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Tschaetsch, H.U.

    2001-02-01

    The article explains a novel, artificial intelligence-based system called HISS (Human Interface Supervision System) which has been installed as a prototype for the monitoring of a natural gas production site at Thoense near Hannover/Germany. The system is capable to perform audio-visual and smelling functions, analogous to the human sensory perception. (orig./CB) [German] Die Aufrechterhaltung eines einwandfreien Betriebszustandes von technischen Anlagen durch staendige Kontrollen und regelmaessige Wartungsarbeiten ist haeufig eine aufwendige und kostspielige Angelegenheit. Gleichwohl ist sie - sowohl was die Frage der Sicherheit als auch des Umweltschutzes anbelangt - unentbehrlich. Die Erdgasfoerderanlage Thoense bei Hannover wird von einem intelligenten Ueberwachungssystem, HISS - Human Interface Supervision System, kontrolliert, das die menschlichen Eigenschaften sehen, hoeren und riechen beherrscht. (orig.)

  9. New exponential synchronization criteria for time-varying delayed neural networks with discontinuous activations.

    Science.gov (United States)

    Cai, Zuowei; Huang, Lihong; Zhang, Lingling

    2015-05-01

    This paper investigates the problem of exponential synchronization of time-varying delayed neural networks with discontinuous neuron activations. Under the extended Filippov differential inclusion framework, by designing discontinuous state-feedback controller and using some analytic techniques, new testable algebraic criteria are obtained to realize two different kinds of global exponential synchronization of the drive-response system. Moreover, we give the estimated rate of exponential synchronization which depends on the delays and system parameters. The obtained results extend some previous works on synchronization of delayed neural networks not only with continuous activations but also with discontinuous activations. Finally, numerical examples are provided to show the correctness of our analysis via computer simulations. Our method and theoretical results have a leading significance in the design of synchronized neural network circuits involving discontinuous factors and time-varying delays. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Discontinued students in nursing education - Who and why?

    Science.gov (United States)

    Kukkonen, Pia; Suhonen, Riitta; Salminen, Leena

    2016-03-01

    There has been increasing interest in student nurse attrition due to the high level of attrition rates in many countries. Studies about nursing education and attrition have been conducted internationally, but only a few have explored attrition from the perspective of the students' own experiences. The purpose of this study was to describe who is a discontinued student in nursing education and the students' own experiences of reasons for leaving a nursing school. A descriptive design and qualitative approach was used. 25 nursing students were interviewed at two different universities of applied sciences in Finland. Four different types of discontinued nursing students were identified: those who moved to another school, those who faced a life crisis, those who made the wrong career choice and those who lived 'busy years'. The results show that the nursing student population is diverse, which has an effect on the students' career intentions, their learning and their ability to cope with studies. In nursing education, it is important to identify students who are at risk of discontinue their studies and develop individual support systems to help nursing students complete their studies and enter into the workforce. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Expert System for support of natural gas network management; Sistema especialista para gerenciamento de redes de gas natural: SEGRED

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jonny Carlos da [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Hirano, Eduardo Wulff [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Lab. de Hidraulica e Pneumatica (LASHIP); Moura, Newton Reis de [PETROBRAS, Rio de Janeiro, RJ (Brazil); Freire, Luiz Gustavo de Melo [PETROBRAS S.A., Pojuca, BA (Brazil). Unidade de Negocios de Gas Natural (UNGN)

    2004-07-01

    This work reports on the SEGRED project, which aims to develop an expert system for management of natural gas transportation networks. The system is currently being developed by LASHIP-UFSC in partnership with PETROBRAS/CENPES and TBG. The SEGRED system consists of an environment designed to support natural gas pipeline management by means of remote supervision of process parameters and analysis of the mutual interactions of those parameters by an expert system integrated to a dynamic simulator. The system is deployed through a process that contributes to making available for use the knowledge about functions such as line packing analysis and line break detection, thus enhancing the quality of execution of these tasks, which are related to the management of natural gas transportation network. The main benefits consist of promoting efforts to acquire and organize expert knowledge. This process contributes to the generation of a knowledge base with corporate technical memory, which can be made available in a permanent, expansible and useful way for decision-making. (author)

  12. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show ... 100 > ± 0.1, DP is observed. This criterion points to diffusional coherency strain theory to be the operative mechanism for DP.

  13. Problems with Discontinuous Diffusion/Dispersion Coefficients

    Directory of Open Access Journals (Sweden)

    Stefano Ferraris

    2012-01-01

    accurate on smooth solutions and based on a special numerical treatment of the diffusion/dispersion coefficients that makes its application possible also when such coefficients are discontinuous. Numerical experiments confirm the convergence of the numerical approximation and show a good behavior on a set of benchmark problems in two space dimensions.

  14. General practitioners’ decisions about discontinuation of medication

    DEFF Research Database (Denmark)

    Nixon, Michael Simon; Vendelø, Morten Thanning

    2016-01-01

    Purpose – The purpose of this paper is to investigate how general practitioners’ (GPs) decisions about discontinuation of medication are influenced by their institutional context. Design/methodology/approach – In total, 24 GPs were interviewed, three practices were observed and documents were...

  15. Multiple discontinuities for 2-to-4 processes

    International Nuclear Information System (INIS)

    Cahill, Kevin; Stapp, H.P.

    1976-01-01

    Formulas that express the multiple normal-threshold discontinuities of scattering functions for 2-to-4 processes as sums of products of scattering amplitudes for related processes are derived from a combination field-theory and S-matrix principles [fr

  16. Forecasting Technological Discontinuities in the ICT Industry

    DEFF Research Database (Denmark)

    Hoisl, Karin; Stelzer, Tobias; Biala, Stefanie

    2015-01-01

    in the ICT industry. The conjoint approach allows for a simulation of the forecasting process and considers utility trade-offs. The results show that for both types of experts the perceived benefit of users most highly contributes to predicting technological discontinuities. Internal experts assign more...

  17. An equilibrium closure result for discontinuous games

    NARCIS (Netherlands)

    Balder, E.J.

    2011-01-01

    For games with discontinuous payoffs Simon and Zame (1990) introduced payoff indeterminacy, in the form of endogenous sharing rules, which are measurable selections of a certain payoff correspondence. Their main result concerns the existence of a mixed Nash equilibrium and an associated sharing

  18. 38 CFR 21.7135 - Discontinuance dates.

    Science.gov (United States)

    2010-07-01

    ... education, the discontinuance date of educational assistance shall be the last date of attendance. (b) Death... veteran is receiving additional educational assistance based on a child's school attendance between the..., withdraws from all courses or receives all nonpunitive grades, and in either case there are no mitigating...

  19. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, , has been calculated and predicted that if 100 > ± 0.1, DP is ...

  20. Hydrogen Rich Natural Gas as a Fuel for SOFC Systems

    OpenAIRE

    Leucht, Florian; Henke, Moritz; Willich, Caroline; Westner, Christina; Kallo, Josef; Friedrich, K. Andreas

    2012-01-01

    With the increase in installed renewable power in Europe and especially in Germany, the need for energy storage becomes urgent. One interesting option due to its high energy density is the generation of hydrogen from renewable electricity using electrolysis. Produced hydrogen can either be sold as fuel for mobile applications or it can be stored in existing infrastructure. One major storage capability is the natural gas pipeline network in which a huge amount of energy can be stored and distr...

  1. Programed Death is Favored by Natural Selection in Spatial Systems.

    Science.gov (United States)

    Werfel, Justin; Ingber, Donald E; Bar-Yam, Yaneer

    2015-06-12

    Standard evolutionary theories of aging and mortality, implicitly based on mean-field assumptions, hold that programed mortality is untenable, as it opposes direct individual benefit. We show that in spatial models with local reproduction, programed deaths instead robustly result in long-term benefit to a lineage, by reducing local environmental resource depletion via spatiotemporal patterns causing feedback over many generations. Results are robust to model variations, implying that direct selection for shorter life span may be quite widespread in nature.

  2. ROLE OF DISCRETE NATURE OF CHIP FORMATION AND NATURAL VIBRATIONS OF SYSTEM COMPONENTS IN CHATTER FORMATION DURING METAL CUTTING

    Directory of Open Access Journals (Sweden)

    A. K. M. Nurulamin

    2010-05-01

    Full Text Available In the present work a review of the existing theories of chatter formation has been conducted and the weaknesses of the most widely accepted ‘Regenerative Chatter theory’ in explaining various phenomena related to chatter formation have been identified. An attempt has been made in this work to determine the common causes of chatter formation in different metal cutting operations, namely, turning, thread cutting and end milling conducted on plain carbon steel AISI 1040. Experimental investigations have been conducted during the above types of machining processes to identify the marks of instability and chatter on the formed chips. It has been identified that in all the three machining operations the chips formed show a common type of discreteness in the form of secondary saw teeth, which appear at the free edge of the chip. Mechanism of formation of these teeth has been studied and the frequencies of their formation have been determined for different cutting conditions. Apart from the secondary saw teeth primary saw teeth have also been identified at the main section of the chip and their frequencies were also determined. At the same time the natural vibrations of the main system components have been identified and the acceleration amplitudes at the prominent natural frequencies during actual machining were recoded using a dedicated vibration monitoring system. The frequencies of secondary chip serration and the natural frequencies of the system components were plotted against cutting speed. Acceleration amplitudes at the prominent natural frequencies were also plotted separately against cutting force. Based on comparison and analysis of these two frequency and amplitude graphs it was concluded that chatter (vibration with relatively high amplitude appears in the system when the frequency of secondary saw teeth approaches values equal to half or integer multiple of a prominent natural frequency of the system resulting in resonance. In the

  3. H4: A challenging system for natural orbital functional approximations

    International Nuclear Information System (INIS)

    Ramos-Cordoba, Eloy; Lopez, Xabier; Piris, Mario; Matito, Eduard

    2015-01-01

    The correct description of nondynamic correlation by electronic structure methods not belonging to the multireference family is a challenging issue. The transition of D 2h to D 4h symmetry in H 4 molecule is among the most simple archetypal examples to illustrate the consequences of missing nondynamic correlation effects. The resurgence of interest in density matrix functional methods has brought several new methods including the family of Piris Natural Orbital Functionals (PNOF). In this work, we compare PNOF5 and PNOF6, which include nondynamic electron correlation effects to some extent, with other standard ab initio methods in the H 4 D 4h /D 2h potential energy surface (PES). Thus far, the wrongful behavior of single-reference methods at the D 2h –D 4h transition of H 4 has been attributed to wrong account of nondynamic correlation effects, whereas in geminal-based approaches, it has been assigned to a wrong coupling of spins and the localized nature of the orbitals. We will show that actually interpair nondynamic correlation is the key to a cusp-free qualitatively correct description of H 4 PES. By introducing interpair nondynamic correlation, PNOF6 is shown to avoid cusps and provide the correct smooth PES features at distances close to the equilibrium, total and local spin properties along with the correct electron delocalization, as reflected by natural orbitals and multicenter delocalization indices

  4. Long-range interactions and the sign of natural amplitudes in two-electron systems

    NARCIS (Netherlands)

    Giesbertz, K.J.H.; Van Leeuwen, R.

    In singlet two-electron systems, the natural occupation numbers of the one-particle reduced density matrix are given as squares of the natural amplitudes which are defined as the expansion coefficients of the two-electron wave function in a natural orbital basis. In this work, we relate the sign of

  5. Monolithic natural gas storage delivery system based on sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Hornbostel, Marc; Krishnan, Gopala N.; Sanjurjo, Angel

    2016-09-27

    The invention provides methods for producing a strong, light, sorbent-based storage/dispenser system for gases and fuels. The system comprises a porous monolithic material with an adherent strong impervious skin that is capable of storing a gas under pressure in a safe and usable manner.

  6. Do marine natural products interfere with prokaryotic AHL regulatory systems?

    DEFF Research Database (Denmark)

    Kjelleberg, S.; Steinberg, P.; Givskov, Michael Christian

    1997-01-01

    inhibited in a fashion that suggests that both classes of compounds have affinity for the same receptor site in the AHL regulatory system. Finally, by performing structure- function experiments on the inhibition of AHL systems by a range of different furanones, we identified the structural prerequisites...

  7. Systems biology approaches to understand natural products biosynthesis

    Directory of Open Access Journals (Sweden)

    Cuauhtemoc eLicona-Cassani

    2015-12-01

    Full Text Available Actinomycetes populate soils and aquatic sediments which impose biotic and abiotic challenges for their survival. As a result, actinomycetes metabolism and genomes have evolved to produce an overwhelming diversity of specialized molecules. Polyketides, non-ribosomal peptides, post-translationally modified peptides, lactams and terpenes are well known bioactive natural products with enormous industrial potential. Accessing such biological diversity has proven difficult due to the complex regulation of cellular metabolism in actinomycetes and to the sparse knowledge of their physiology. The past decade, however, has seen the development of omics technologies that have significantly contributed to our better understanding of their biology. Key observations have contributed towards a shift in the exploitation of actinomycetes biology, such as using their full genomic potential, activating entire pathways through key metabolic elicitors and pathway engineering to improve biosynthesis. Here, we review recent efforts devoted to achieving enhanced discovery, activation and manipulation of natural product biosynthetic pathways in model actinomycetes using genome-scale biological datasets.

  8. Stress-assisted discontinuous precipitation during creep of Ti3Al-Nb alloys

    International Nuclear Information System (INIS)

    Rowe, R.G.; Hall, E.L.

    1991-01-01

    This paper reports on stress-assisted discontinuous precipitation observed during creep of Ti-25Al-12.5Nb at.% and associated with microstructures in which large primary creep strains are observed. It was found that a large shift between the equilibrium β 0 (B2) phase composition at the heat treatment temperature and disordered β (bcc) phase at the creep temperature provided a driving force for discontinuous precipitation of disordered beta phase. Applied stress accelerated the growth of discontinuous β phase at grain boundaries perpendicular to the principal stress axis, but did not produce a significant shift in composition. The difference between beta and ordered beta phase boundaries in the Ti-Al-Nb system at 650 degrees C and 1040 degrees C suggests that discontinuous precipitation or related dissolution should occur in all Ti 3 Al-Nb alloys

  9. 28 CFR 16.99 - Exemption of the Immigration and Naturalization Service Systems-limited access.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Exemption of the Immigration and....99 Exemption of the Immigration and Naturalization Service Systems-limited access. (a) The following systems of records of the Immigration and Naturalization Service are exempt from 5 U.S.C. 552a (c) (3) and...

  10. Yellowstone wolves and the forces that structure natural systems.

    Directory of Open Access Journals (Sweden)

    Andy P Dobson

    2014-12-01

    Full Text Available Since their introduction in 1995 and 1996, wolves have had effects on Yellowstone that ripple across the entire structure of the food web that defines biodiversity in the Northern Rockies ecosystem. Ecological interpretations of the wolves have generated a significant amount of debate about the relative strength of top-down versus bottom-up forces in determining herbivore and vegetation abundance in Yellowstone. Debates such as this are central to the resolution of broader debates about the role of natural enemies and climate as forces that structure food webs and modify ecosystem function. Ecologists need to significantly raise the profile of these discussions; understanding the forces that structure food webs and determine species abundance and the supply of ecosystem services is one of the central scientific questions for this century; its complexity will require new minds, new mathematics, and significant, consistent funding.

  11. Assessing the impacts of climate change on natural resource systems

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, K.D.; Rosenberg, N.J. [eds.

    1994-11-30

    This volume is a collection of papers addressing the theme of potential impacts of climatic change. Papers are entitled Integrated Assessments of the Impacts of Climatic Change on Natural Resources: An Introductory Editorial; Framework for Integrated Assessments of Global Warming Impacts; Modeling Land Use and Cover as Part of Global Environmental Change; Assessing Impacts of Climatic Change on Forests: The State of Biological Modeling; Integrating Climatic Change and Forests: Economic and Ecological Assessments; Environmental Change in Grasslands: Assessment using Models; Assessing the Socio-economic Impacts of Climatic Change on Grazinglands; Modeling the Effects of Climatic Change on Water Resources- A Review; Assessing the Socioeconomic Consequences of Climate Change on Water Resources; and Conclusions, Remaining Issues, and Next Steps.

  12. Natural solar energy amplifiers in planet-atmosphere system

    International Nuclear Information System (INIS)

    Njau, E. C.

    2004-01-01

    Planets and their atmospheres (including the Earth and its atmosphere) continuously receive solar energy which comprises very small variable components and a relatively huge constant component. On the basis of certain conditions, specific physical mechanism can exist in each planet-atmosphere system under which the tiny variable solar energy components so received apparently undergo large amplifications. In the case of the Earth-Atmosphere system, these energy amplifications continuously exist and involve maximum amplification factors that range from ∼ 2312 to over 6915 for frequencies equal to or less than the 11-year sunspot cycle frequency. Consequently energy and hence temperature variations at the solar (or sunspot) cycle frequencies dominantly exist in the Earth-Atmosphere system. These energy and temperature variations are continuously mapped or translated into corresponding variations in the other weather parameters as verified by past records

  13. Natural ionizing system to electrical protection and energy; Sistema ionizante natural de proteccion electrica y energias

    Energy Technology Data Exchange (ETDEWEB)

    Cabareda Fermin; Luis [Universidad de Los Andes (Venezuela)]. E-mail: lcabaredaf@gmail.com

    2013-03-15

    This is the new highest technology, 100% Venezuelan and unique in the world, technological innovation, world patent for maximum protection, security and zero risk (0) to all electrical and power generation systems: hydroelectric and thermoelectric power plants, wind, nuclear and solar power plants, etc; it's the only technology around the world that has the potential to disperse and propagate to land mass the enormous energies associated to the atmospheric discharges (lightning), which are in the order: 200,000 to 500,000 Amperes; 1,000 million Kilowatts and high-level transient voltage of 100 million Volts. This new high technology is the solution to the paradigm of Benjamin Franklin and it is the mechanism to end blackouts that produce so many damages and losses of billions of dollars to both generators and users of electrical service, throughout the world. [Spanish] Esta nueva mas alta tecnologia, 100% venezolana y unica en el mundo, innovacion tecnologica, patente mundial ofrece maxima proteccion, seguridad y riesgo cero (0) a todos los sistemas de generacion electrica: centrales hidroelectricas, termoelectricas, de viento, nucleares y solar, otros; es la unica tecnologia en el mundo que tiene el potencial para dispersar y propagar a la masa terrestre las enormes energias asociadas a las descargas atmosfericas (rayos) que estan en el orden de: 200.000 a 500.000 amperios, 1.000 millones de kilovatios y voltajes transitorios de alto nivel de 100 millones de voltios. Esta nueva alta tecnologia es la solucion al paradigma de Benjamin Franklin y es el mecanismo para eliminar apagones que producen danos y perdidas de billones de dolares para ambos: generados y usuarios del servicio electrico, alrededor del mundo.

  14. Complex Systems Education for natural Hazards and from down to up Pushing of Government and Officials: A Case Study

    Science.gov (United States)

    Zvelebil, J.

    2009-04-01

    interplays of highly organized entities. Of course, such efforts mainly fail due to existence of qualitative differences between description of the same phenomena on different time-space scales or functional levels. Main features of a basic course "Application of nonlinear dynamics and Theory of Complex Systems for Physical Geographers" are described. They also partially follow the course reader's opinion about necessity of new reunion of modern philosophy and methodology of natural and human sciences Dangerous distortion of reflections of reality by the frequently proposed substitution of human science methodology by the natural science one is stressed. On the contrary, examples from philosophy (Bergson 1919, Wittgenstein 1953), which had anticipated and even defined some profound themes of Complex Systems (e.g. Kauffman 1993), as e.g. self-organizing, entropy decreasing behavior, or existence of discontinuities between description of the same phenomena on different time-space scales or functional levels. The second priority has information dissemination for decisions makers of natural Hazards management. Any successful Case history is better then ten popular lectures for those decision makers. A case history of highly computerized Integrated Information System (IIS) for unstable rock slope monitoring, on-line rock fall precursors diagnostics of time series and automated early warning launching, the both with the use of predominantly nonlinear tools is outlined. It stands to support author's opinion that pushing of officials is effective only if it is provided from down to up. That means it is based on satisfactory solution of specific community needs, instead of from up to down flowing more or less general directives of some far away sitting clerks. The third tactical item is rather long-distance run. Change of paradigm cannot be ordered, it is matter of generation change, as on scientific, as well as on decision makers (hopefully recruited from students already aware of

  15. A study of velocity discontinuity for single air bubbles rising in an associative polymer

    Science.gov (United States)

    Soto, E.; Goujon, C.; Zenit, R.; Manero, O.

    2006-12-01

    The motion of air bubbles in aqueous solutions of a hydrophobic alkali-swellable associative polymer is studied in this work. The associative nature of these polymer systems dictates their rheological properties: for moderate values of the shear rate, the formation of structure can lead to a shear-thickening behavior and to the appearance of first normal stress difference. For larger shear rates, the polymer associations can be broken, leading to shear thinning. In general, these fluids show a Newtonian behavior for small values of the shear rate, but behave as viscoelastic liquids for large shear rates. Experimental results show the appearance of a critical bubble volume at which a discontinuity in the relation velocity-volume occurs; however, the velocity increase found in this case is not as large as that previously reported for the case of shear-thinning viscoelastic fluids. The discontinuity is associated with a significant change of the bubble shape: before the critical volume, the bubbles are convex spheroids, while past the critical volume a sharp cusped end appears. The appearance of the tail is also associated with the appearance of an inflection point (change of curvature) on the bubble surface. Moreover, since the rheology of the liquids is measured it was found that the discontinuity, and hence the change of shape, occurs when the elastic nature of the liquid first manifests itself (appearance of a first normal stress difference). A comparison of the measured velocities for small bubbles with predictions from a Stokes-Hadamard law shows a discrepancy. The Newtonian viscosity measured in a viscometric flow was smaller than that determined from a falling-ball arrangement. Considering the viscosity measured under this nonviscometric flow, the comparison between theory and experiments was very good for bubbles having volumes lower than the critical one. Moreover, due to the importance of the elasticity, and due to the change of the shape of the bubble, a

  16. The Enigmatic Nature of the Israeli Legal System

    African Journals Online (AJOL)

    10332324

    South Africa. She argues convincingly that the current unrecognised status of Muslim marriages is not favourable to women because their marriages fall outside the realm of the mainstream legal systems in South Africa (the common and the customary law). She continues to discuss two Bills in various stages of evolution ...

  17. A Linguistic Image of Nature: The Burmese Numerative Classifier System

    Science.gov (United States)

    Becker, Alton L.

    1975-01-01

    The Burmese classifier system is coherent because it is based upon a single elementary semantic dimension: deixis. On that dimension, four distances are distinguished, distances which metaphorically substitute for other conceptual relations between people and other living beings, people and things, and people and concepts. (Author/RM)

  18. The Enigmatic Nature of the Israeli Legal System

    African Journals Online (AJOL)

    NWUuser

    multilateral trading system. Instead there is a steady rise to power by emerging economies, especially those of Brazil, Russia, India, China and South Africa. These countries form the now familiar BRICS front and are now considered future economic powerhouses that can contribute to the construction of a new international.

  19. Electrochemical metal speciation in natural and model polyelectrolyte systems

    NARCIS (Netherlands)

    Hoop, van den M.A.G.T.

    1994-01-01

    The purpose of the research described in this thesis was to examine the applicability of electro-analytical techniques in obtaining information on the speciation of metals, i.e. their distribution over different physico-chemical forms, in aquatic systems containing charged macromolecules.

  20. The natural horn as an efficient sound radiating system ...

    African Journals Online (AJOL)

    Results obtained showed that the locally made horn are efficient sound radiating systems and are therefore excellent for sound production in local musical renditions. These findings, in addition to the portability and low cost of the horns qualify them to be highly recommended for use in music making and for other purposes ...

  1. Natural resource use by agricultural systems : linking biodiversity to poverty

    NARCIS (Netherlands)

    Tonneijck, A.E.G.; Hengsdijk, H.; Bindraban, P.S.

    2006-01-01

    Agricultural development is a well-known threat to the conservation of biodiversity and the loss and fragmentation of native habitats. It also is considered to be an important engine of economic development in developing countries. Changes in agricultural production systems might affect directly

  2. The Enigmatic Nature of the Israeli Legal System

    African Journals Online (AJOL)

    RV

    Many have, of course, since developed their own custom-made intellectual property law systems. In the majority of ... development has been recognised.9 Economic development, "'a process of structural transformations' ..... appropriately be attributed to factors such as an adverse business environment and the influence of ...

  3. A Sanctuary for Science: The Hastings Natural History Reservation and the Origins of the University of California's Natural Reserve System.

    Science.gov (United States)

    Alagona, Peter S

    2012-01-01

    In 1937 Joseph Grinnell founded the University of California's (U.C.) first biological field station, the Hastings Natural History Reservation. Hastings became a center for field biology on the West Coast, and by 1960 it was serving as a model for the creation of additional U.C. reserves. Today, the U.C. Natural Reserve System (NRS) is the largest and most diverse network of university-based biological field stations in the world, with 36 sites covering more than 135,000 acres. This essay examines the founding of the Hastings Reservation, and asks how it managed to grow and develop, in the 1940s and 1950s, during a time of declining support for natural history research. It shows how faculty and staff courted the support of key institutional allies, presented themselves as the guardians of a venerable tradition in nature study, and emphasized the station's capacity to document ecological change and inform environmental policy and management. In the years since, Hastings and other U.C. reserves have played crucial roles in California environmental politics. Biological field stations in the post-war era deserve more attention not only from historians of biology, but also from environmental historians and other scholars interested in the role of science in society.

  4. Discontinuation of Preventive Drugs in General Practice

    DEFF Research Database (Denmark)

    Andersen, John Sahl; Lindberg, Laura Maria Glahder; Nixon, Michael Simon

    Introduction: In Denmark about 600,000 persons are treated for hypertension and more than 300,000 people are receiving cholesterol lowering drugs. The prevalence of hypertension in people aged 80 years is 70%. For antidepressants the defined daily doses/1000 aged >80 years/day exceed 200. By far...... the most preventive drugs are prescribed in general practice. Special considerations exist in relation to medication of elderly patients. The prevalence of polypharmacy and the subsequent increased risk of side effects and drug interactions is high. Drug-related problems represent the fifth leading cause...... of death in the United States. The public expenses to drug treatment are constantly increasing. The possibility to withdraw the medication must be taken into account but the decision to discontinue drugs is complex and poorly understood. Planned studies: 1. Patients’ views upon discontinuation...

  5. Flight Testing of an Advanced Airborne Natural Gas Leak Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Dawn Lenz; Raymond T. Lines; Darryl Murdock; Jeffrey Owen; Steven Stearns; Michael Stoogenke

    2005-10-01

    ITT Industries Space Systems Division (Space Systems) has developed an airborne natural gas leak detection system designed to detect, image, quantify, and precisely locate leaks from natural gas transmission pipelines. This system is called the Airborne Natural Gas Emission Lidar (ANGEL) system. The ANGEL system uses a highly sensitive differential absorption Lidar technology to remotely detect pipeline leaks. The ANGEL System is operated from a fixed wing aircraft and includes automatic scanning, pointing system, and pilot guidance systems. During a pipeline inspection, the ANGEL system aircraft flies at an elevation of 1000 feet above the ground at speeds of between 100 and 150 mph. Under this contract with DOE/NETL, Space Systems was funded to integrate the ANGEL sensor into a test aircraft and conduct a series of flight tests over a variety of test targets including simulated natural gas pipeline leaks. Following early tests in upstate New York in the summer of 2004, the ANGEL system was deployed to Casper, Wyoming to participate in a set of DOE-sponsored field tests at the Rocky Mountain Oilfield Testing Center (RMOTC). At RMOTC the Space Systems team completed integration of the system and flew an operational system for the first time. The ANGEL system flew 2 missions/day for the duration for the 5-day test. Over the course of the week the ANGEL System detected leaks ranging from 100 to 5,000 scfh.

  6. System model of a natural circulation integral test facility

    Science.gov (United States)

    Galvin, Mark R.

    The Department of Nuclear Engineering and Radiation Health Physics (NE/RHP) at Oregon State University (OSU) has been developing an innovative modular reactor plant concept since being initiated with a Department of Energy (DoE) grant in 1999. This concept, the Multi-Application Small Light Water Reactor (MASLWR), is an integral pressurized water reactor (PWR) plant that utilizes natural circulation flow in the primary and employs advanced passive safety features. The OSU MASLWR test facility is an electrically heated integral effects facility, scaled from the MASLWR concept design, that has been previously used to assess the feasibility of the concept design safety approach. To assist in evaluating operational scenarios, a simulation tool that models the test facility and is based on both test facility experimental data and analytical methods has been developed. The tool models both the test facility electric core and a simulated nuclear core, allowing evaluation of a broad spectrum of operational scenarios to identify those scenarios that should be explored experimentally using the test facility or design-quality multi-physics tools. Using the simulation tool, the total cost of experimentation and analysis can be reduced by directing time and resources towards the operational scenarios of interest.

  7. Hybridized Multiscale Discontinuous Galerkin Methods for Multiphysics

    Science.gov (United States)

    2015-09-14

    Helmholtz equation for a very wide range of wave frequencies, 4) presented an embedded discontinuous Galerkin (EDG) method for numerically ...of freedom (for the same mesh and polynomial degree of the approximation) in comparison to the well-established finite element methods for diffusion... equations , J. Comput. Phys., 228 (2009), pp. 8841–8855. [4] N.-C. NGUYEN, J. PERAIRE, AND B. COCKBURN, A comparison of HDG methods for Stokes flow, J.

  8. A Discontinuous Galerkin Model for Fluorescence Loss in Photobleaching

    DEFF Research Database (Denmark)

    Hansen, Christian Valdemar; Schroll, Achim; Wüstner, Daniel

    2018-01-01

    Galerkin method, the computational complexity is drastically reduced compared to continuous Galerkin methods. Using this approach on green uorescent protein (GFP), we can determine its intracellular di usion constant, the strength of localized hindrance to di usion as well as the permeability......Fluorescence loss in photobleaching (FLIP) is a modern microscopy method for visualization of transport processes in living cells. This paper presents the simulation of FLIP sequences based on a calibrated reaction–di usion system de ned on segmented cell images. By the use of a discontinuous...

  9. Expert System for natural gas transportation network management; Sistema especialista para gerenciamento de redes de transporte de gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jonny Carlos da; Porciuncula, Gilson Simoes [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica Lab. de Sistemas Hidraulicos e Pneumaticos

    2003-07-01

    This paper presents a project to integrate expert system and dynamic simulation of natural gas transportation network applying the concept of agents. Natural gas pipeline operation requires the intermittent analysis of hundreds interrelated operational parameters, which represent the network state. The combination of expert system and dynamic simulation is a synergic solution for this kind of problem. With expert system techniques, it is possible to implement rules that describe the relationship between current operational parameters and the network normal operational conditions based on heuristic knowledge. By applying such rules, the system aims to evaluate the real network state and to predict abnormal conditions via dynamic simulation, allowing time analysis of operational situation in advance. At the current stage, the project presents a well defined model. The process of knowledge acquisition and representation has taken place following an incremental approach, considered as development paradigm. The project objectives are to reduce costs, increase the reliability and organize pipeline operation and maintenance information. This work is part of SEGRED project established as partnership among LASHIP/UFSC, SCGAS, TBG and PETROBRAS. The project also received support from FINEP. (author)

  10. Discontinuity effects in dynamically loaded tilting pad journal bearings

    DEFF Research Database (Denmark)

    Thomsen, Kim; Klit, Peder; Vølund, Anders

    2011-01-01

    This paper describes two discontinuity effects that can occur when modelling radial tilting pad bearings subjected to high dynamic loads. The first effect to be treated is a pressure build-up discontinuity effect. The second effect is a contact-related discontinuity that disappears when a contact...... force is included in the theoretical model. Methods for avoiding the pressure build-up discontinuity effect are proposed....

  11. Entropy: A Unifying Path for Understanding Complexity in Natural, Artificial and Social Systems

    Science.gov (United States)

    2011-07-01

    us now address complex systems which include a substantial social component. We may start with economics and theory of finance. Given the long memory ...Entropy: A Unifying Path for Understanding Complexity in Natural, Artificial and Social Systems * Constantino Tsallis Centro Brasileiro de...Path for Understanding Complexity in Natural, Artificial and Social Systems 5a. CONTRACT NUMBER FA23861114006 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  12. Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems

    Directory of Open Access Journals (Sweden)

    Romeu de Souza Werner

    Full Text Available ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense of Brazil. The treatments, which included mowed natural rangeland (NR, burned natural rangeland (BR, natural rangeland improved through the introduction of plant species after harrowing (IH, and natural rangeland improved through the introduction of plant species after chisel plowing (IC, were evaluated in a Nitossolo Bruno (Nitisol. In the improved treatments, soil acidity was corrected, phosphate fertilizer was applied, and intercropped annual ryegrass (Lolium multiflorum, velvet grass (Holcus lanatus, and white clover (Trifolium repens were sown. Management systems with harrowed or chisel plowed soil showed improved soil physical properties; however, the effect decreased over time and values approached those of burned and mowed natural rangelands. Natural rangeland systems in the establishment phase had little influence on soil organic C. The mowed natural rangeland and improved natural rangeland exhibited greater production of grazing material, while burning the field decreased production and increased the proportion of weeds. Improvement of the natural rangelands increased leguminous biomass for pasture.

  13. 25 CFR 175.21 - Discontinuance of service.

    Science.gov (United States)

    2010-04-01

    ... Utility Service Administration § 175.21 Discontinuance of service. Failure of customer(s) to comply with... 25 Indians 1 2010-04-01 2010-04-01 false Discontinuance of service. 175.21 Section 175.21 Indians... service. The procedure(s) for discontinuance of service shall be set forth in the operations manual. ...

  14. 27 CFR 555.61 - Discontinuance of business or operations.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Discontinuance of business... Permits § 555.61 Discontinuance of business or operations. Where an explosive materials business or operations is either discontinued or succeeded by a new owner, the owner of the business or operations...

  15. Seismic wave propagation in fractured media: A discontinuous Galerkin approach

    KAUST Repository

    De Basabe, Jonás D.

    2011-01-01

    We formulate and implement a discontinuous Galekin method for elastic wave propagation that allows for discontinuities in the displacement field to simulate fractures or faults using the linear- slip model. We show numerical results using a 2D model with one linear- slip discontinuity and different frequencies. The results show a good agreement with analytic solutions. © 2011 Society of Exploration Geophysicists.

  16. Technical description of the Swedish natural gas distribution system

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ronny [KM Miljoeteknik AB (Sweden)

    1997-06-01

    This description of the Swedish distribution network has been produced to provide information for distribution companies, trade organisations, etc., who have an interest in getting a clear understanding of the technical design and standards, technical directives, etc., which have served as guidance in the development. The technical description covers the piping system from a measuring and regulating station (MR station) up to the consumer`s substation, however, only sections with a maximum operating pressure of 4 bar. By way of introduction, the description contains introductory information on supply channels, consumption patterns and the principal design of the high pressure network in Sweden 10 refs, 10 figs, 1 tab

  17. Controlled Ecological Life Support Systems: Natural and Artificial Ecosystems

    Science.gov (United States)

    Macelroy, Robert D. (Editor); Thompson, Brad G. (Editor); Tibbitts, Theodore W. (Editor); Volk, Tyler (Editor)

    1989-01-01

    The scientists supported by the NASA sponsored Controlled Ecological Life Support Systems (CELSS) program have played a major role in creating a Committee on Space Research (COSPAR) section devoted to the development of bioregenerative life support for use in space. The series of 22 papers were sponsored by Subcommission F.4. The papers deal with many of the diverse aspects of life support, and with outgrowth technologies that may have commercial applications in fields such as biotechnology and bioengineering. Papers from researchers in France, Canada, Japan and the USSR are also presented.

  18. The Nature of Unintended Benefits in Health Information Systems

    DEFF Research Database (Denmark)

    Kuziemsky, Craig E.; Borycki, Elizabeth; Nøhr, Christian

    2012-01-01

    Health information systems (HISs) have been shown to introduce unintended consequences post implementation. Much of the current research on these consequences has focused on the negative aspects of them. However unintended consequences of HIS usage can also be beneficial to various aspects...... of healthcare delivery. This paper uses several case studies of HIS implementation to develop a model of unintended benefits of HIS usage with three categories of benefits: patient, service delivery and administrative. We also discuss the implications of these benefits on the design and evaluation of HISs....

  19. Fracture systems and mesoscale structural patterns in the siliciclastic mesozoic reservoir-caprock succession of the longyearbyen CO2 lab project: Implications for geological CO2 sequestration in central spitsbergen, svalbard

    NARCIS (Netherlands)

    Ogata, Kei; Senger, Kim; Braathen, Alvar; Tveranger, Jan; Olaussen, Snorre

    2014-01-01

    In unconventional, naturally fractured reservoirs, networks of structural discontinuities largely control fluid flow. In this study, we mapped and analysed systematic fracture patterns within the Mesozoic succession of Central Spitsbergen to characterise the reservoir-caprock system explored for

  20. Molecular communications and nanonetworks from nature to practical systems

    CERN Document Server

    Atakan, Barış

    2014-01-01

    In this book, the concepts of molecular communications and nanonetworks are introduced. Throughout the book, the existing molecular communication paradigms are categorized into two main groups. The first group includes the Passive Molecular Communication (PMC) paradigms in which molecules freely diffuse to transfer information from a transmitter to a receiver. The second group includes the Active Molecular Communication (AMC) paradigms in which molecules are carried or guided by some mediators such as molecular motors, gap junction channels and bacteria. In the book, after briefly discussing why molecular communication is needed for the sophisticated nano and biotechnology applications, the existing molecular communication systems are first presented. Then, the principles of diffusion phenomena and molecular reception with absorbers and the ligand-receptor binding mechanism are introduced. Based on these principles, the communication theories and techniques are given for the PMC. Then, the physical dynamics o...

  1. Nonregenerative natural resources in a sustainable system of energy supply.

    Science.gov (United States)

    Bradshaw, Alex M; Hamacher, Thomas

    2012-03-12

    Following the lead of the European Union in introducing binding measures to promote the use of regenerative energy forms, it is not unreasonable to assume that the global demand for combustible raw materials for energy generation will be reduced considerably in the second half of this century. This will not only have a favourable effect on the CO(2) concentration in the atmosphere, but will also help preserve fossil fuels-important as raw materials in the chemical industry-for future generations. Nevertheless, associated with the concomitant massive shift to regenerative energy forms, there will be a strong demand for other exhaustible raw materials, in particular metals, some of which are already regarded as scarce. After reviewing the debate on mineral depletion between "cornucopians" and "pessimists", we discuss the meaning of mineral "scarcity", particularly in the geochemical sense, and mineral "exhaustion". The expected drastic increase in demand for mineral resources caused by demographic and societal pressures, that is, due to the increase in in-use stock, is emphasised. Whilst not discussing the issue of "strong" versus "weak" sustainability in detail, we conclude that regenerative energy systems-like nearly all resource-consuming systems in our society-do not necessarily satisfy generally accepted sustainability criteria. In this regard, we discuss some current examples, namely, lithium and cobalt for batteries, rare earth-based permanent magnets for wind turbines, cadmium and tellurium for solar cells and copper for electrical power distribution. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Super-convergence of Discontinuous Galerkin Method Applied to the Navier-Stokes Equations

    Science.gov (United States)

    Atkins, Harold L.

    2009-01-01

    The practical benefits of the hyper-accuracy properties of the discontinuous Galerkin method are examined. In particular, we demonstrate that some flow attributes exhibit super-convergence even in the absence of any post-processing technique. Theoretical analysis suggest that flow features that are dominated by global propagation speeds and decay or growth rates should be super-convergent. Several discrete forms of the discontinuous Galerkin method are applied to the simulation of unsteady viscous flow over a two-dimensional cylinder. Convergence of the period of the naturally occurring oscillation is examined and shown to converge at 2p+1, where p is the polynomial degree of the discontinuous Galerkin basis. Comparisons are made between the different discretizations and with theoretical analysis.

  3. Visual system evolution and the nature of the ancestral snake.

    Science.gov (United States)

    Simões, B F; Sampaio, F L; Jared, C; Antoniazzi, M M; Loew, E R; Bowmaker, J K; Rodriguez, A; Hart, N S; Hunt, D M; Partridge, J C; Gower, D J

    2015-07-01

    The dominant hypothesis for the evolutionary origin of snakes from 'lizards' (non-snake squamates) is that stem snakes acquired many snake features while passing through a profound burrowing (fossorial) phase. To investigate this, we examined the visual pigments and their encoding opsin genes in a range of squamate reptiles, focusing on fossorial lizards and snakes. We sequenced opsin transcripts isolated from retinal cDNA and used microspectrophotometry to measure directly the spectral absorbance of the photoreceptor visual pigments in a subset of samples. In snakes, but not lizards, dedicated fossoriality (as in Scolecophidia and the alethinophidian Anilius scytale) corresponds with loss of all visual opsins other than RH1 (λmax 490-497 nm); all other snakes (including less dedicated burrowers) also have functional sws1 and lws opsin genes. In contrast, the retinas of all lizards sampled, even highly fossorial amphisbaenians with reduced eyes, express functional lws, sws1, sws2 and rh1 genes, and most also express rh2 (i.e. they express all five of the visual opsin genes present in the ancestral vertebrate). Our evidence of visual pigment complements suggests that the visual system of stem snakes was partly reduced, with two (RH2 and SWS2) of the ancestral vertebrate visual pigments being eliminated, but that this did not extend to the extreme additional loss of SWS1 and LWS that subsequently occurred (probably independently) in highly fossorial extant scolecophidians and A. scytale. We therefore consider it unlikely that the ancestral snake was as fossorial as extant scolecophidians, whether or not the latter are para- or monophyletic. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  4. Emergency field water supply system using natural filtration elements

    Science.gov (United States)

    Vikneswaran, M.; Yahya, Muhamad Azani; Yusof, Mohammed Alias; Ismail, Siti Nor Kamariah

    2018-02-01

    Water is the most important resource in times of emergency and during military missions. In addition, if there is a war in a country, sources of clean water are essential for life. But, the safety and cleanliness of the river water for the campers and hikers still uncertain. Usually, polluted and contaminated river water is not safe to be directly consumed by human. However, this problem can be partly resolved by using water filter where the river water can be consumed directly after the filtration process. In respect of that, this study was conducted to design the filter media for personal water purification system. Hence, the objective of this work also is to develop a personal, portable dual purpose handy water filter to provide an easier way to get safe, clean and healthy drinking water for human wherever they go. The water quality of samples collected before and after filtration were analyzed. Water samples were taken from a waterfall near Lestari Block and Lake beside Marine Centre UPNM Campus. The experimental results were analyzed based on the assessment of water quality parameters. Overall, the analysis of the results showed that the water filter was designed with basic mix tabs aqua filter water purification tablets is showing a better result where it achieve the class I of water quality index (WQI). In details, the water sample taken from waterfall near Lestari Block shown the WQI around 93 which is higher than WQI of water sample from Lake near Marine Centre UPNM which is 86, class II A which can be used for external purpose only.

  5. Soil cover by natural trees in agroforestry systems

    Science.gov (United States)

    Diaz-Ambrona, C. G. H.; Almoguera Millán, C.; Tarquis Alfonso, A.

    2009-04-01

    The dehesa is common agroforestry system in the Iberian Peninsula. These open oak parklands with silvo-pastoral use cover about two million hectares. Traditionally annual pastures have been grazed by cows, sheep and also goats while acorns feed Iberian pig diet. Evergreen oak (Quercus ilex L.) has other uses as fuelwood collection and folder after tree pruning. The hypothesis of this work is that tree density and canopy depend on soil types. We using the spanish GIS called SIGPAC to download the images of dehesa in areas with different soil types. True colour images were restoring to a binary code, previously canopy colour range was selected. Soil cover by tree canopy was calculated and number of trees. Processing result was comparable to real data. With these data we have applied a dynamic simulation model Dehesa to determine evergreen oak acorn and annual pasture production. The model Dehesa is divided into five submodels: Climate, Soil, Evergreen oak, Pasture and Grazing. The first three require the inputs: (i) daily weather data (maximum and minimum temperatures, precipitation and solar radiation); (ii) the soil input parameters for three horizons (thickness, field capacity, permanent wilting point, and bulk density); and (iii) the tree characterization of the dehesa (tree density, canopy diameter and height, and diameter of the trunk). The influence of tree on pasture potential production is inversely proportional to the canopy cover. Acorn production increase with tree canopy cover until stabilizing itself, and will decrease if density becomes too high (more than 80% soil tree cover) at that point there is competition between the trees. Main driving force for dehesa productivity is soil type for pasture, and tree cover for acorn production. Highest pasture productivity was obtained on soil Dystric Planosol (Alfisol), Dystric Cambisol and Chromo-calcic-luvisol, these soils only cover 22.4% of southwest of the Iberian peninssula. Lowest productivity was

  6. Computerized map-based information management system for natural resource management

    Energy Technology Data Exchange (ETDEWEB)

    Miller, K.

    1995-12-01

    Federal agencies, states and resource managers have control and stewardship responsibility over a significant inventory of natural resources. A number of federal regulations require the review, protection and preservation of natural resource protection. Examples of such actions include the reauthorization of the Clean Water Act and the modification of the National Contingency Plan to incorporate the requirements of the Oil Pollution Act of 1990. To successfully preserve conserve and restore natural resources on federal reservations, and state and private lands, and to comply with Federal regulations designed to protect natural resources located on their sites, and the type of information on these resources required by environmental regulations. This paper presents an approach using a computerized, graphical information management system to catalogue and track data for the management of natural resources under Federal and state regulations, and for promoting resource conservation, preservation and restoration. The system is designed for use by Federal facility resource managers both for the day-to-day management of resources under their control, and for the longer-term management of larger initiatives, including restoration of significant or endangered resources, participation in regional stewardship efforts, and general ecosystem management. The system will be valuable for conducting natural resource baseline inventories an implementing resource management plans on lands other than those controlled by the Federal government as well. The system can provide a method for coordinating the type of natural resource information required by major federal environmental regulations--thereby providing a cost-effective means for managing natural resource information.

  7. Natural Language Understanding Systems Within the A. I. Paradigm: A Survey and Some Comparisons.

    Science.gov (United States)

    Wilks, Yorick

    The paper surveys the major projects on the understanding of natural language that fall within what may now be called the artificial intelligence paradigm of natural language systems. Some space is devoted to arguing that the paradigm is now a reality and different in significant respects from the generative paradigm of present-day linguistics.…

  8. Discontinuous finite element treatment of duct problems in transport calculations

    International Nuclear Information System (INIS)

    Mirza, A. M.; Qamar, S.

    1998-01-01

    A discontinuous finite element approach is presented to solve the even-parity Boltzmann transport equation for duct problems. Presence of ducts in a system results in the streaming of particles and hence requires the employment of higher order angular approximations to model the angular flux. Conventional schemes based on the use of continuous trial functions require the same order of angular approximations to be used everywhere in the system, resulting in wastage of computational resources. Numerical investigations for the test problems presented in this paper indicate that the discontinuous finite elements eliminate the above problems and leads to computationally efficient and economical methods. They are also found to be more suitable for treating the sharp changes in the angular flux at duct-observer interfaces. The new approach provides a single-pass alternate to extrapolation and interactive schemes which need multiple passes of the solution strategy to acquire convergence. The method has been tested with the help of two case studies, namely straight and dog-leg duct problems. All results have been verified against those obtained from Monte Carlo simulations and K/sup +/ continuous finite element method. (author)

  9. Stakeholder Workshop Presentations: EPA Greenhouse Gas Data on Petroleum and Natural Gas Systems

    Science.gov (United States)

    View the summary and presentations from the November 2015 stakeholder workshop on greenhouse gas data on petroleum and natural gas systems from the Greenhouse Gas Reporting Program and U.S. Greenhouse Gas Inventory of Emissions and Sinks.

  10. Fate of nuclides in natural water systems. Annual progress report, April 1, 1983-March 31, 1984

    International Nuclear Information System (INIS)

    Turekian, K.K.

    1983-01-01

    This study of the behavior of nuclides in natural water systems is divided into studies of atmospheric aerosols, soils, groundwater, rivers, estuaries and coastal zones, the carbon cycle and the growth rates of marine organisms

  11. Modeling the transient security constraints of natural gas network in day-ahead power system scheduling

    DEFF Research Database (Denmark)

    Yang, Jingwei; Zhang, Ning; Kang, Chongqing

    2017-01-01

    accurately, they are hard to be embedded into the power system scheduling model, which consists of algebraic equations and inequations. This paper addresses this dilemma by proposing an algebraic transient model of natural gas network which is similar to the branch-node model of power network. Based......The rapid deployment of gas-fired generating units makes the power system more vulnerable to failures in the natural gas system. To reduce the risk of gas system failure and to guarantee the security of power system operation, it is necessary to take the security constraints of natural gas...... pipelines into account in the day-ahead power generation scheduling model. However, the minute- and hour-level dynamic characteristics of gas systems prevents an accurate decision-making simply with the steady-state gas flow model. Although the partial differential equations depict the dynamics of gas flow...

  12. Status, Antimicrobial Mechanism, and Regulation of Natural Preservatives in Livestock Food Systems

    OpenAIRE

    Lee, Na-Kyoung; Paik, Hyun-Dong

    2016-01-01

    This review discusses the status, antimicrobial mechanisms, application, and regulation of natural preservatives in livestock food systems. Conventional preservatives are synthetic chemical substances including nitrates/nitrites, sulfites, sodium benzoate, propyl gallate, and potassium sorbate. The use of artificial preservatives is being reconsidered because of concerns relating to headache, allergies, and cancer. As the demand for biopreservation in food systems has increased, new natural a...

  13. Decision-support systems for natural-hazards and land-management issues

    Science.gov (United States)

    Dinitz, Laura; Forney, William; Byrd, Kristin

    2012-01-01

    Scientists at the USGS Western Geographic Science Center are developing decision-support systems (DSSs) for natural-hazards and land-management issues. DSSs are interactive computer-based tools that use data and models to help identify and solve problems. These systems can provide crucial support to policymakers, planners, and communities for making better decisions about long-term natural hazards mitigation and land-use planning.

  14. A Discontinuous Unscented Kalman Filter for Non-Smooth Dynamic Problems

    Directory of Open Access Journals (Sweden)

    Manolis N. Chatzis

    2017-10-01

    Full Text Available For a number of applications, including real/time damage diagnostics as well as control, online methods, i.e., methods which may be implemented on-the-fly, are necessary. Within a system identification context, this implies adoption of filtering algorithms, typically of the Kalman or Bayesian class. For engineered structures, damage or deterioration may often manifest in relation to phenomena such as fracture, plasticity, impact, or friction. Despite the different nature of the previous phenomena, they are described by a common denominator: switching behavior upon occurrence of discrete events. Such events include for example, crack initiation, transitions between elastic and plastic response, or between stick and slide modes. Typically, the state-space equations of such models are non-differentiable at such events, rendering the corresponding systems non-smooth. Identification of non-smooth systems poses greater difficulties than smooth problems of similar computational complexity. Up to a certain extent, this may be attributed to the varying identifiability of such systems, which violates a basic requirement of online Bayesian Identification algorithms, thus affecting their convergence for non-smooth problems. Herein, a treatment to this problem is proposed by the authors, termed the Discontinuous D– modification, where unidentifiable parameters are acknowledged and temporarily excluded from the problem formulation. In this work, the D– modification is illustrated for the case of the Unscented Kalman Filter UKF, resulting in a method termed DUKF, proving superior performance to the conventional, and widely adopted, alternative.

  15. Development of a Natural Rearing System to Improve Supplemental Fish Quality, 1991-1995 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Maynard, Desmond J.; Flagg, Thomas A.; Mahnken, Conrad V.W.

    1996-08-01

    In this report, the National Marine Fisheries Service (NMFS), in collaboration with the Bonneville Power Administration (BPA), the Washington State Department of Fish and Wildlife (WDFW), and the US Fish and Wildlife Service (USFWS), presents research findings and guidelines for development and evaluation of innovative culture techniques to increase postrelease survival of hatchery fish. The Natural Rearing Enhancement System (NATURES) described in this report is a collection of experimental approaches designed to produce hatchery-reared chinook salmon (Oncorhynchus tshawytscha) that exhibit wild-like behavior, physiology, and morphology. The NATURES culture research for salmonids included multiple tests to develop techniques such as: raceways equipped with cover, structure, and natural substrates to promote development of proper body camouflage coloration; feed-delivery systems that condition fish to orient to the bottom rather than the surface of the rearing vessel; predator conditioning of fish to train them to avoid predators; and supplementing diets with natural live foods to improve foraging ability. The underlying assumptions are that NATURES will: (1) promote the development of natural cryptic coloration and antipredator behavior; (2) increase postrelease foraging efficiency; (3) improve fish health and condition by alleviating chronic, artificial rearing habitat-induced stress; and (4) reduce potential genetic selection pressures induced by the conventional salmon culture environment. A goal in using NATURES is to provide quality fish for rebuilding depleted natural runs.

  16. Orbital energies and negative electron affinities from density functional theory: Insight from the integer discontinuity

    Science.gov (United States)

    Teale, Andrew M.; de Proft, Frank; Tozer, David J.

    2008-07-01

    Orbital energies in Kohn-Sham density functional theory (DFT) are investigated, paying attention to the role of the integer discontinuity in the exact exchange-correlation potential. A series of closed-shell molecules are considered, comprising some that vertically bind an excess electron and others that do not. High-level ab initio electron densities are used to calculate accurate orbital energy differences, Δɛ, between the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO), using the same potential for both. They are combined with accurate vertical ionization potentials, I0, and electron affinities, A0, to determine accurate ``average'' orbital energies. These are the orbital energies associated with an exchange-correlation potential that averages over a constant jump in the accurate potential, of magnitude ΔXC=(I0-A0)-Δɛ, as given by the discontinuity analysis. Local functional HOMO energies are shown to be almost an order of magnitude closer to these average values than to -I0, with typical discrepancies of just 0.02 a.u. For systems that do not bind an excess electron, this level of agreement is only achieved when A0 is set equal to the negative experimental affinity from electron transmission spectroscopy (ETS); it degrades notably when the zero ground state affinity is instead used. Analogous observations are made for the local functional LUMO energies, although the need to use the ETS affinities is less pronounced for systems where the ETS values are very negative. The application of an asymptotic correction recovers the preference, leading to positive LUMO energies (but bound orbitals) for these systems, consistent with the behavior of the average energies. The asymptotically corrected LUMO energies typically agree with the average values to within 0.02 a.u., comparable to that observed with the HOMOs. The study provides numerical support for the view that local functionals exhibit a near-average behavior

  17. Characterization of natural circulation looping of emergency cooling systems in naval and advanced reactors

    International Nuclear Information System (INIS)

    Macedo, Luiz Alberto; Baptista Filho, Benedito Dias

    2000-01-01

    This paper describes the natural circuit looping, resumes the main project characteristics, presents results of the hydraulic characterization, consisting of pressure loss measurements, and presents results from calibration tests of the power and flow measurements and the first experiments in natural circulation. Those experiments comprised transients in natural circulation with application of application of power steps. The results shown a non linear behaviour of the magnetic flow meter and a dependence on the fluid temperature as well. The assembly circuit/instrumentation/data acquisition system is suitable for the research on emergency cooling passive systems

  18. A carborne gamma-ray spectrometer system for natural radioactivity mapping and environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Grasty, R.L.; Cox, J.R. [Exploranium Ltd., Mississauga, Ontario (Canada)

    1997-12-31

    This paper summarizes the experience gained in the use of a carborne gamma-ray spectrometer system for mapping both natural and man-made radiation. Particular emphasis is placed on the calibration of the system for converting the gamma-ray measurements to ground concentrations of potassium, uranium and thorium and the activity of {sup 137}Cs. During the Finnish Emergency Response Exercise (Resume95), the carborne system was shown to be effective in mapping both natural and man-made radiation from {sup 137}Cs fallout and in locating radioactive sources. The application of the carborne system for mineral exploration is also demonstrated. (au). 10 refs.

  19. Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

    International Nuclear Information System (INIS)

    1995-01-01

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A

  20. Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-02-17

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A.

  1. New pre-heating system for natural gas pressure regulating stations

    International Nuclear Information System (INIS)

    Zullo, G.; Vertuani, C.; Borghesani, O.; Vignoli, F.

    1999-01-01

    Costs for running natural gas pressure regulating stations are mainly due to operation and maintenance of a natural gas preheating system, usually equipment with a hot water boiler or an armour-plated electric resistance immersed in a fluid. The article describe a system, considering a natural circulation boiler which uses steam/condensate (at 100 degrees C and 0,5 bar) as a thermal conductor, in thermodynamic balance and in absence of un condensable. This new boiler, already operating with satisfactory results in heating system for industrial buildings, does not require testing, notifications, periodical inspections by the competent authorities, constant monitoring by trained or patented staff. Besides, it allows easier installations procedures and running cost savings. The system, to be considered as static because it has no moving parts, is a good alternative to conventional forced hot water circulation or electric heating system [it

  2. Discontinuity of Breastfeeding Care: "There's No Captain of the Ship".

    Science.gov (United States)

    Garner, Christine D; Ratcliff, Stephannie L; Thornburg, Loralei L; Wethington, Elaine; Howard, Cynthia R; Rasmussen, Kathleen M

    2016-01-01

    Breastfeeding rates in the United States are suboptimal. Health professionals (HPs) have a unique opportunity to support breastfeeding because of the frequency and timing of their visits with mothers and infants as well as their call by professional organizations to do so. The objective of this study was to understand HPs' perceived roles and experiences with providing breastfeeding-related care. In-depth qualitative interviews were conducted with 34 HPs (obstetricians, midwives, pediatricians, nurses, and lactation consultants) who care for pregnant or lactating women. Interviews were audio-recorded, transcribed, and verified for accuracy; content analysis was used to identify themes using a grounded theory approach. The overarching theme was discontinuity in breastfeeding care across the continuum. Most HPs relied on other HPs to provide breastfeeding care, which resulted from and contributed to problematic gaps in care that were reported. A minority of HPs attempted to bridge gaps in breastfeeding care or improve continuity. Contributing to the discontinuity were a lack of time, lack of skills, inconsistent messages, and low communication across stages of care. HPs were unsure whether their help was effective and whether required follow-up was completed. Despite HPs' recognition of breastfeeding as the best choice for infant feeding, breastfeeding care may be disjointed and a barrier to achieving breastfeeding recommendations. These problems should be investigated and systemically addressed in future research so that maternal-infant dyad breastfeeding care can be improved.

  3. Regulation causes nitrogen cycling discontinuities in Mediterranean rivers.

    Science.gov (United States)

    von Schiller, Daniel; Aristi, Ibon; Ponsatí, Lídia; Arroita, Maite; Acuña, Vicenç; Elosegi, Arturo; Sabater, Sergi

    2016-01-01

    River regulation has fundamentally altered large sections of the world's river networks. The effects of dams on the structural properties of downstream reaches are well documented, but less is known about their effect on river ecosystem processes. We investigated the effect of dams on river nutrient cycling by comparing net uptake of total dissolved nitrogen (TDN), phosphorus (TDP) and organic carbon (DOC) in river reaches located upstream and downstream from three reservoir systems in the Ebro River basin (NE Iberian Peninsula). Increased hydromorphological stability, organic matter standing stocks and ecosystem metabolism below dams enhanced the whole-reach net uptake of TDN, but not that of TDP or DOC. Upstream from dams, river reaches tended to be at biogeochemical equilibrium (uptake≈release) for all nutrients, whereas river reaches below dams acted as net sinks of TDN. Overall, our results suggest that flow regulation by dams may cause relevant N cycling discontinuities in rivers. Higher net N uptake capacity below dams could lead to reduced N export to downstream ecosystems. Incorporating these discontinuities could significantly improve predictive models of N cycling and transport in complex river networks. Copyright © 2015. Published by Elsevier B.V.

  4. Bifurcation in autonomous and nonautonomous differential equations with discontinuities

    CERN Document Server

    Akhmet, Marat

    2017-01-01

    This book is devoted to bifurcation theory for autonomous and nonautonomous differential equations with discontinuities of different types. That is, those with jumps present either in the right-hand-side or in trajectories or in the arguments of solutions of equations. The results obtained in this book can be applied to various fields such as neural networks, brain dynamics, mechanical systems, weather phenomena, population dynamics, etc. Without any doubt, bifurcation theory should be further developed to different types of differential equations. In this sense, the present book will be a leading one in this field. The reader will benefit from the recent results of the theory and will learn in the very concrete way how to apply this theory to differential equations with various types of discontinuity. Moreover, the reader will learn new ways to analyze nonautonomous bifurcation scenarios in these equations. The book will be of a big interest both for beginners and experts in the field. For the former group o...

  5. Plutonium - its behavior in natural-water systems and assimilation by man

    International Nuclear Information System (INIS)

    Larsen, R.P.; Nelson, D.M.; Bhattacharyya, M.H.; Oldham, R.D.

    1981-01-01

    There are a number of factors which must be considered in establishing whether or not the inadvertent intrusion of a sizable amount of plutonium-bearing material into a natural-water system may have a significant impact on the health of those individuals who use that system as a drinking-water resource. These factors include the chemical form(s) and solubility of plutonium in natural waters, its behavior in relation to natural processes (geochemical and biological), its fate in water-treatment systems, and its uptake by man from drinking water. From the results obtained of the behavior in natural-water systems, it appears that (1) the chemical forms of plutonium dissolved in natural waters are Pu(IV) and Pu(V), (2) the soluble plutonium in many waters is bound to the organic constituents which probably enhance plutonium solubility, (3) the natural process responsible for the removal of plutonium from water is adsorption onto sediments, and (4) in water-treatment systems, soluble plutonium is oxidized to the VI state and this form is not removed. From investigations of gastrointestinal absorption, it appears that the value for f 1 , the fraction transferred from the gut to blood, is greater than 1 x 10 - 3 and may be as high as 2 x 10 - 1

  6. Discontinuous hygroscopic growth of an aqueous surfactant/salt aerosol particle levitated in an electrodynamic balance

    Science.gov (United States)

    Soonsin, V.; Krieger, U. K.; Peter, T.

    2010-12-01

    Organic compounds are a major fraction of tropospheric aerosol. The organic fraction is usually internally mixed with inorganic salts. Surface-active organic matter or surfactants, enriched in the oceanic surface layer and transferred to the atmosphere by bubble-bursting processes, are the most likely candidates to contribute the observed organic fraction in sea salt aerosol [1, 2]. If the organic substance is a surfactant, it will lower the surface tension. In addition aggregates of the organic monomers, called micelles, will form if the concentration of the organic exceeds a certain limit (critical micelle concentration). These aggregates do have different morphology (spheres or globular or rod like micelles, or spherical bilayer vesicles etc.) and size, depending on the nature of the organic molecule, its concentration and the concentration of inorganic salts [3]. These aggregate may promote solubilisation of organic compounds in aqueous atmospheric aerosol. We performed measurements of ternary aqueous solution particles consisting of tetraethylene glycol monooctyl ether (C8E4) as organic surfactant and sodium chloride (NaCl) as inorganic salt and water (H2O) using single levitated aerosol particles in an electrodynamic balance. The particles can be stored contact-free in a temperature and humidity controlled chamber and optical resonance spectroscopy is used to monitor radius change [4]. Mie resonance spectra of ternary droplets show discontinuous growth with increasing relative humidity (RH) and also discontinuous shrinkage with decreasing relative humidity. We observe this behavior at temperatures and RHs at which the salt is completely deliquesced and the concentration of the organic surfactant is larger than the critical micelle concentration. Independent measurements of particle mass show also discontinuous water uptake. We speculate that this discontinuous, step-like, growth is caused by disaggregation of a micelle needed to conserve the monolayer of

  7. Categorization of hydrogen storage with reference to natural gas storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Venter, R. D.; Selim, M. A. [Toronto Univ., ON (Canada)

    1997-05-01

    This poster session presentation proposes a categorization scheme of hydrogen storage systems based on energy content of the stored hydrogen. The presentation is based on data about various liquid and gaseous hydrogen storage installations and analogous data on storage systems for natural gas. The proposed system would serve to define and differentiate terms such as bulk storage, industrial storage and small storage systems, and would enable the comparison of existing and developing infrastructure requirements in the emerging context of hydrogen storage.

  8. Status, Antimicrobial Mechanism, and Regulation of Natural Preservatives in Livestock Food Systems.

    Science.gov (United States)

    Lee, Na-Kyoung; Paik, Hyun-Dong

    2016-01-01

    This review discusses the status, antimicrobial mechanisms, application, and regulation of natural preservatives in livestock food systems. Conventional preservatives are synthetic chemical substances including nitrates/nitrites, sulfites, sodium benzoate, propyl gallate, and potassium sorbate. The use of artificial preservatives is being reconsidered because of concerns relating to headache, allergies, and cancer. As the demand for biopreservation in food systems has increased, new natural antimicrobial compounds of various origins are being developed, including plant-derived products (polyphenolics, essential oils, plant antimicrobial peptides (pAMPs)), animal-derived products (lysozymes, lactoperoxidase, lactoferrin, ovotransferrin, antimicrobial peptide (AMP), chitosan and others), and microbial metabolites (nisin, natamycin, pullulan, ε-polylysine, organic acid, and others). These natural preservatives act by inhibiting microbial cell walls/membranes, DNA/RNA replication and transcription, protein synthesis, and metabolism. Natural preservatives have been recognized for their safety; however, these substances can influence color, smell, and toxicity in large amounts while being effective as a food preservative. Therefore, to evaluate the safety and toxicity of natural preservatives, various trials including combinations of other substances or different food preservation systems, and capsulation have been performed. Natamycin and nisin are currently the only natural preservatives being regulated, and other natural preservatives will have to be legally regulated before their widespread use.

  9. Proposal for Holistic Assessment of Urban System Resilience to Natural Disasters

    Science.gov (United States)

    Koren, David; Kilar, Vojko; Rus, Katarina

    2017-10-01

    Urban system is a complex mix of interdependent components and dynamic interactions between them that enable it to function effectively. Resilience of urban system indicates the ability of a system to resist, absorb, accommodate to and recover from the effects of a hazard in a timely and efficient manner. In the relevant literature, most studies consider individual components separately. On the other hand, the purpose of this paper is to assess the urban system as a whole, considering all relevant components and their interactions. The goal is a study of possibilities for holistic evaluation of urban system resilience to natural disasters. Findings from the preliminary study are presented: (i) the definition of urban system and categorization of its components, (ii) a set of attributes of individual components with impact on disaster resilience of the entire system and (iii) review of different methods and approaches for resilience assessment. Based on literature review and extensive preliminary studies a new conceptual framework for urban resilience assessment is proposed. In the presented paper, a conceptual model of urban system by abstraction of its components as nodes (buildings), patches - specific nodes with spatial properties (open space), links (infrastructures) and base layer (community) is created. In the suggested model, each component is defined by its own quantitative attributes, which have been identified to have an important impact on the urban system resilience to natural disasters. System is presented as a mathematical graph model. Natural disaster is considered an external factor that affects the existing system and leads to some system distortion. In further analyses, mathematical simulation of various natural disasters scenarios is going to be carried out, followed by comparison of the system functionality before and after the accident. Various properties of the system (accessibility, transition, complexity etc.) are going to be analysed with

  10. Application of remote sensing and Geographic Information Systems to ecosystem-based urban natural resource management

    Science.gov (United States)

    Xiaohui Zhang; George Ball; Eve Halper

    2000-01-01

    This paper presents an integrated system to support urban natural resource management. With the application of remote sensing (RS) and geographic information systems (GIS), the paper emphasizes the methodology of integrating information technology and a scientific basis to support ecosystem-based management. First, a systematic integration framework is developed and...

  11. Multi-Area Predictive Control for Combined Electricity and Natural Gas Systems

    NARCIS (Netherlands)

    Arnold, M.; Negenborn, R.R.; Andersson, G.; De Schutter, B.

    2009-01-01

    The optimal operation of an integrated electricity and natural gas system is investigated. The couplings between these two systems are modeled by energy hubs, which serve as interface between the loads and the transmission infrastructures. Previously, we have applied a distributed control scheme to

  12. Integrating social science into empirical models of coupled human and natural systems

    Science.gov (United States)

    Jeffrey D. Kline; Eric M. White; A Paige Fischer; Michelle M. Steen-Adams; Susan Charnley; Christine S. Olsen; Thomas A. Spies; John D. Bailey

    2017-01-01

    Coupled human and natural systems (CHANS) research highlights reciprocal interactions (or feedbacks) between biophysical and socioeconomic variables to explain system dynamics and resilience. Empirical models often are used to test hypotheses and apply theory that represent human behavior. Parameterizing reciprocal interactions presents two challenges for social...

  13. Nouns Referring to Tools and Natural Objects Differentially Modulate the Motor System

    Science.gov (United States)

    Gough, Patricia M.; Riggio, Lucia; Chersi, Fabian; Sato, Marc; Fogassi, Leonardo; Buccino, Giovanni

    2012-01-01

    While increasing evidence points to a critical role for the motor system in language processing, the focus of previous work has been on the linguistic category of verbs. Here we tested whether nouns are effective in modulating the motor system and further whether different kinds of nouns--those referring to artifacts or natural items, and items…

  14. The influence of an estimated energy saving due to natural ventilation on the Mexican energy system

    DEFF Research Database (Denmark)

    Oropeza-Perez, Ivan; Østergaard, Poul Alberg

    2014-01-01

    This article shows the impacts of the extensive use of NV (natural ventilation) in the Mexican residential sector on the Mexican energy system. By integrating a thermal-airflow simulation programme with an energy systems analysis model, the impact on the Mexican energy system of replacing air...... conditioning, in particular, with natural ventilation to cool residential buildings is determined. It is shown that when, as in Mexico, there is a relatively simple connection between supply and electricity demand, NV creates savings which could be used to reduce either the fossil-fuel-based generation...

  15. Combining a building simulation with energy systems analysis to assess the benefits of natural ventilation

    DEFF Research Database (Denmark)

    Oropeza-Perez, Ivan; Østergaard, Poul Alberg; Remmen, Arne

    2013-01-01

    This article shows the combination of a thermal air flow simulation program with an energy systems analysis model in order to assess the use of natural ventilation as a method for saving energy within residential buildings in large-scale scenarios. The aim is to show the benefits for utilizing...... natural airflow instead of active systems such as mechanical ventilation or air-conditioning in buildings where the indoor temperature is over the upper limit of the comfort range. The combination is done by introducing the energy saving output - calculated with a model of natural ventilation using...... a thermal air flow simulation program - Into the energy systems analysis model. Descriptions of the energy systems in two geographical locations, i.e. Mexico and Denmark, are set up as inputs. Then, the assessment is done by calculating the energy impacts as well as environmental benefits in the energy...

  16. Strategic behavior and governance challenges in self-organized coupled natural-human systems

    Science.gov (United States)

    Muneepeerakul, R.; Anderies, J. M.

    2017-12-01

    Successful and sustainable coupling of human societies and natural systems requires effective governance, which depends on the existence of proper infrastructure (both hard and soft). In recent decades, much attention has been paid to what has allowed many small-scale self-organized coupled natural-human systems around the world to persist for centuries, thanks to a large part to the work by Elinor Ostrom and colleagues. In this work, we mathematically operationalize a conceptual framework that is developed based on this body of work by way of a stylized model. The model captures the interplay between replicator dynamics within the population, dynamics of natural resources, and threshold characteristics of public infrastructure. The model analysis reveals conditions for long-term sustainability and collapse of the coupled systems as well as other tradeoffs and potential pitfalls in governing these systems.

  17. Geometry and Width of the Ringwoodite - Bridgmanite+Ferropericlase Binary Loop in the System (Mg,Fe)2SiO4: Interpretation of the Sharpness of the 660-km Discontinuity

    Science.gov (United States)

    Katsura, T.; Ishii, T.; Huang, R.; Maeda, F.; Yuan, L.; Bhat, S.; Farla, R. J.; Kawazoe, T.; Tsujino, N.; Liu, Z.; Fei, H.; Wang, L.; Druzhbin, D.; Yamamoto, T.; Kulik, E.; Koemets, I.; Higo, Y.; Tange, Y.

    2017-12-01

    Short wave-length seismic reflections from the 660 km discontinuity (D660) indicated an extreme sharp, namely less than 2 km thick boundary. To explain this observation, Ito and Takahashi [1989] estimated that the pressure interval of the dissociation of ringwoodite (Rw) to bridgmanite (Brg) plus ferropericlase (fPc) is hours. Simultaneously, after several trials, the press load was increased at the right rate at the temperature to maintain nearly constant pressure within 0.2 GPa. X-ray diffractions of the samples and pressure maker were taken to determine pressure and phases present. An important finding is that the transition pressure in Fo70 is 0.1 GPa higher than that in Fo100. Namely, the hypothetical transition pressure in Fe2SiO4 is 0.3 GPa higher than the transition pressure in Mg2SiO4. This geometry is contrary to the previous understanding. The obtained pressure difference and the partition coefficients of Fe and Mg among Brg, Rw and fPc suggest that the pressure interval is almost zero, which explains the sharpness of the D660.

  18. Factors predicting successful discontinuation of continuous renal replacement therapy.

    Science.gov (United States)

    Katayama, S; Uchino, S; Uji, M; Ohnuma, T; Namba, Y; Kawarazaki, H; Toki, N; Takeda, K; Yasuda, H; Izawa, J; Tokuhira, N; Nagata, I

    2016-07-01

    This multicentre, retrospective observational study was conducted from January 2010 to December 2010 to determine the optimal time for discontinuing continuous renal replacement therapy (CRRT) by evaluating factors predictive of successful discontinuation in patients with acute kidney injury. Analysis was performed for patients after CRRT was discontinued because of renal function recovery. Patients were divided into two groups according to the success or failure of CRRT discontinuation. In multivariate logistic regression analysis, urine output at discontinuation, creatinine level and CRRT duration were found to be significant variables (area under the receiver operating characteristic curve for urine output, 0.814). In conclusion, we found that higher urine output, lower creatinine and shorter CRRT duration were significant factors to predict successful discontinuation of CRRT.

  19. Natural fracture systems on planetary surfaces: Genetic classification and pattern randomness

    Science.gov (United States)

    Rossbacher, Lisa A.

    1987-01-01

    One method for classifying natural fracture systems is by fracture genesis. This approach involves the physics of the formation process, and it has been used most frequently in attempts to predict subsurface fractures and petroleum reservoir productivity. This classification system can also be applied to larger fracture systems on any planetary surface. One problem in applying this classification system to planetary surfaces is that it was developed for ralatively small-scale fractures that would influence porosity, particularly as observed in a core sample. Planetary studies also require consideration of large-scale fractures. Nevertheless, this system offers some valuable perspectives on fracture systems of any size.

  20. Does Prescribed Randomness Hold the Key to Interface Synthetic and Natural Systems?

    Science.gov (United States)

    Xu, Ting

    The bottlenecks to engineering biomimetic functional materials are not only to duplicate hierarchical structures, but also to manipulate the system dynamics. Bio-inspired responsive materials have been investigated extensively within the past few decades with much success. Yet, the level of control of these complex systems is still rather simplistic. More importantly, we have yet to uncover the design rules to synergize natural and synthetic building blocks that allows us to go beyond just a few specific families of natural building blocks. I am going to discuss our recent studies that demonstrated the feasibility to develop synthetic protein-like polymers that can interface with natural proteins and biomachinaries. Rational design of these protein-like polymers thus opens a viable approach toward functional materials based on natural components. The work is supported by DOD-ARO W911NF-16-1-0405.

  1. USING CUSTOM TRIFLANGE IMPLANT IN REVISION HIP ARTHROPLASTY IN PATIENT WITH PELVIC DISCONTINUITY (CASE REPORT

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2016-01-01

    Full Text Available Revision hip arthroplasty rate is growing, and pelvic discontinuity rate ranges from 1% to 5% of acetabular component revision reasons. According to AAOS acetabular defects classification, pelvic discontinuity is fourth type defect in which cranial part of hip bone is separated from caudal part at acetabular level. Usually it occurs from bone loss secondary to osteolysis, infection, fracture or aseptic loosening. There are a lot of techniques for pelvis discontinuity treatment. Published results of bulk allografts and antiprotrusion cages have generally been poor. More preferable methods with acceptable rate of good results are cup-cage systems and custom triflange acetabular components(CTAC. CTACs are designed based on preoperative CT scans to build a custom titanium 3D-printed implant to address the patient's specific bone defect and provide secure fixation in the ilium, pubis, and ischium. We faced pelvic discontinuity, in which extensive iliac bone loss was added to caudal hip bone part medial displacement and pelvic ring deformity, in patient with multiple hip surgeries. Preoperative investigation called into question the possibility of using off-the-shelf hip implants, which could restore the biomechanics of the hip and provide reliable primary fixation at the same time. We present case report of the patient with pelvic discontinuity and massive bone loss treatment using a custom triflange component.

  2. A hyper-spherical adaptive sparse-grid method for high-dimensional discontinuity detection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guannan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Webster, Clayton G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gunzburger, Max D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burkardt, John V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-03-01

    This work proposes and analyzes a hyper-spherical adaptive hierarchical sparse-grid method for detecting jump discontinuities of functions in high-dimensional spaces is proposed. The method is motivated by the theoretical and computational inefficiencies of well-known adaptive sparse-grid methods for discontinuity detection. Our novel approach constructs a function representation of the discontinuity hyper-surface of an N-dimensional dis- continuous quantity of interest, by virtue of a hyper-spherical transformation. Then, a sparse-grid approximation of the transformed function is built in the hyper-spherical coordinate system, whose value at each point is estimated by solving a one-dimensional discontinuity detection problem. Due to the smoothness of the hyper-surface, the new technique can identify jump discontinuities with significantly reduced computational cost, compared to existing methods. Moreover, hierarchical acceleration techniques are also incorporated to further reduce the overall complexity. Rigorous error estimates and complexity analyses of the new method are provided as are several numerical examples that illustrate the effectiveness of the approach.

  3. Studies of natural analogues and geological systems. Their importance to performance assessment

    International Nuclear Information System (INIS)

    Brandberg, F.; Grundfelt, B.; Hoeglund, L.O.; Skagius, K.; Karlsson, Fred; Smellie, J.

    1992-04-01

    This review has involved studies of natural analogues and natural geological systems leading to the identification and quantification of processes and features of importance to the performance and safety of repositories for radioactive waste. The features and processes selected for the study comprise general geochemical issues related to the performance of the near- and of the far-field, the performance and durability of construction materials and the effects of glaciation. For each of these areas a number of potentially important processes for repository performance have been described, and evidence for their existence, as well as quantification of parameters of models describing the processes, have been sought from major natural analogue studies and site investigations. The review has aimed at covering a relatively broad range of issues at the expense of in-depth analysis. The quantitative data presented are in most cases compilations of data from the literature; in a few cases results of evaluations made within the current project are included. The results of the study show that studies of natural analogues and natural geological systems have provided significant information regarding many issues of importance to repository performance. In several cases the evidence from natural analogues has demonstrated that processes assumed to take place in repositories actually occur in natural systems or under conditions similar to those predicted to prevail in a future repository. One example of such a process is coprecipitation of fission products and ferric oxyhydroxides as an analogue to corrosion products from a steel canister. In addition, the study of concentration gradients of uranium and other trace substances in the rock surrounding groundwater conduits confirm that matrix diffusion occurs in nature and that the diffusivities in the rock matrix measured in the laboratory are consistent with the observations in nature

  4. Hydrate Formation/Dissociation in (Natural Gas + Water + Diesel Oil Emulsion Systems

    Directory of Open Access Journals (Sweden)

    Chang-Yu Sun

    2013-02-01

    Full Text Available Hydrate formation/dissociation of natural gas in (diesel oil + water emulsion systems containing 3 wt% anti-agglomerant were performed for five water cuts: 5, 10, 15, 20, and 25 vol%. The natural gas solubilities in the emulsion systems were also examined. The experimental results showed that the solubility of natural gas in emulsion systems increases almost linearly with the increase of pressure, and decreases with the increase of water cut. There exists an initial slow hydrate formation stage for systems with lower water cut, while rapid hydrate formation takes place and the process of the gas-liquid dissolution equilibrium at higher water cut does not appear in the pressure curve. The gas consumption amount due to hydrate formation at high water cut is significantly higher than that at low water cut. Fractional distillation for natural gas components also exists during the hydrate formation process. The experiments on hydrate dissociation showed that the dissociation rate and the amount of dissociated gas increase with the increase of water cut. The variations of temperature in the process of natural gas hydrate formation and dissociation in emulsion systems were also examined.

  5. Discontinuation of Opiate Treatment: A Retrospective Review of 49 Patients

    OpenAIRE

    Alen J Salerian

    2015-01-01

    This retrospective study reviews 49 patients- one year with opiate and one year post treatment discontinuation - treated at a private outpatient psychopharmacology center. This retrospective study reviews the health status of 398 patients with two distinct subgroups, 17 local and 32 out-of-town patients. Results revealed significant rise in fatalities after opiate discontinuation. The review results are consistent with increased risk of premature death following opiate discontinuation. It may...

  6. Discontinuity minimization for omnidirectional video projections

    Science.gov (United States)

    Alshina, Elena; Zakharchenko, Vladyslav

    2017-09-01

    Advances in display technologies both for head mounted devices and television panels demand resolution increase beyond 4K for source signal in virtual reality video streaming applications. This poses a problem of content delivery trough a bandwidth limited distribution networks. Considering a fact that source signal covers entire surrounding space investigation reviled that compression efficiency may fluctuate 40% in average depending on origin selection at the conversion stage from 3D space to 2D projection. Based on these knowledge the origin selection algorithm for video compression applications has been proposed. Using discontinuity entropy minimization function projection origin rotation may be defined to provide optimal compression results. Outcome of this research may be applied across various video compression solutions for omnidirectional content.

  7. Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. Subsequent chapters of this report provide: an overview of NGTDM; a description of the interface between the NEMS and NGTDM; an overview of the solution methodology of the NGTDM; the solution methodology for the Annual Flow Module; the solution methodology for the Distributor Tariff Module; the solution methodology for the Capacity Expansion Module; the solution methodology for the Pipeline Tariff Module; and a description of model assumptions, inputs, and outputs.

  8. Disaster Management System as an Element of Risk Management for Natural Disaster Systems Using the PESTLE Framework

    OpenAIRE

    Sarwar, D; Ramachandran, M; Hosseinian Far, A

    2017-01-01

    Recently, we have witnessed so many natural catastrophes such as earthquakes in Japan, severe floods in the UK, US and many other parts of the world. Consequently businesses have been losing tens of billions of dollars as a result of various natural and man-made disasters. Disaster Management System (DMS) have proven to be important means for reducing risks associated with such damages to businesses. A DMS can minimize and in some cases, eliminates the risks through technical, management or o...

  9. Factors related to continuous and discontinuous attendance at memory clinics.

    Science.gov (United States)

    Hishikawa, N; Fukui, Y; Nakano, Y; Morihara, R; Takemoto, M; Sato, K; Yamashita, T; Ohta, Y; Abe, K

    2017-05-01

    Few studies have examined why some patients with dementia stop attending medical consultations. We conducted a retrospective study to investigate factors associated with discontinuous clinic attendance. Participants were 988 patients with dementia from university hospital (UH) clinics and affiliated local hospital (LH) clinics. We compared continuous and discontinuous attenders on cognitive and affective functions and activities of daily living (ADL), and also compared UH and LH patients (UH: continuous, n = 176; discontinuous, n = 207; LH: continuous, n = 418; discontinuous, n = 187). The total annual rate of discontinuation was 8.0%, and the mean period of attendance before discontinuation was 2.2 ± 2.4 years (UH, 2.8 ± 3.0; LH, 1.5 ± 1.3, P attendance at their own discretion (35.3% for LH). We identified the main reasons for discontinuation of attendance as returning to the family doctor and cessation of hospital attendance at their own discretion. The best predictors of discontinuation were ADL decline and worsening BPSD. There were significant differences in discontinuation between UH and LH patients with dementia. © 2017 EAN.

  10. A system for the analysis of tritium content in natural waters, through benzene

    International Nuclear Information System (INIS)

    Bocchi, N.

    1980-01-01

    A system is described for the analysis of tritium ( 3 H) in natural waters. The system consists of an electrolytic enrichment equipment and a vacuum line for benzene synthesis. The benzene is mixed with a scintillating solution and so used in tritium activity measurements by liquid scintillation spectrometry. The characteristcs of the system, as well as its performance, are pointed out through analysis of ground and rain waters. The precision and reproducibility of the measurements are discussed. (Author) [pt

  11. Prevalence and associated factors of contraceptive discontinuation and switching among Bangladeshi married women of reproductive age

    Directory of Open Access Journals (Sweden)

    Mahumud RA

    2015-01-01

    Full Text Available Rashidul Alam Mahumud,1 Md Golam Hossain,2 Abdur Razzaque Sarkar,1 Md Nurul Islam,2 Md Ripter Hossain,2 Aik Saw,3 Jahangir AM Khan1,4 1Health Economics and Financing Research Group, Center for Equity and Health Systems, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh; 2Department of Statistics, University of Rajshahi, Rajshahi, Bangladesh; 3Department of Orthopaedic Surgery, National Orthopaedic Centre of Excellence for Research and Learning, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; 4Adjunct Faculty, Health Economics Unit, Department of Learning, Informatics, Management and Ethics, Karolinska Institutet, Stockholm, Sweden Introduction: Contraceptive discontinuation is a worldwide incident that may be connected with low incentive to avoid pregnancy. Contraceptive discontinuation highly contributes to unplanned pregnancy and unwanted births.Objectives: The objective of this study was to observe the prevalence of discontinuation and switching of contraceptive methods among Bangladeshi married women. In addition, the sociodemographic factors associated with contraceptive discontinuation and switching were assessed.Methods: Secondary cross-sectional data was used in this study. A total of 16,273 married Bangladeshi women of reproductive age (15–49 years were considered in the present study, from the Bangladesh Demographic and Health Survey, 2011. Logistic regression models were used to determine the relationships between key sociodemographic factors and user status.Results: The prevalence of discontinuation and switching of contraceptive method among women were 38.4% and 15.4%, respectively. The logistic regression model demonstrated that women in early reproductive years (25–29 years and 30–34 years significantly more often (odds ratio [OR] =0.84 and 0.71, respectively discontinued use of contraceptives. Significantly higher rates of discontinuation were pronounced among women who

  12. Natural ventilation systems to enhance sustainability in buildings: a review towards zero energy buildings in schools

    Science.gov (United States)

    Gil-Baez, Maite; Barrios-Padura, Ángela; Molina-Huelva, Marta; Chacartegui, Ricardo

    2017-11-01

    European regulations set the condition of Zero Energy Buildings for new buildings since 2020, with an intermediate milestone in 2018 for public buildings, in order to control greenhouse gases emissions control and climate change mitigation. Given that main fraction of energy consumption in buildings operation is due to HVAC systems, advances in its design and operation conditions are required. One key element for energy demand control is passive design of buildings. On this purpose, different recent studies and publications analyse natural ventilation systems potential to provide indoor air quality and comfort conditions minimizing electric power consumption. In these passive systems are of special relevance their capacities as passive cooling systems as well as air renovation systems, especially in high-density occupied spaces. With adequate designs, in warm/mild climates natural ventilation systems can be used along the whole year, maintaining indoor air quality and comfort conditions with small support of other heating/cooling systems. In this paper is analysed the state of the art of natural ventilation systems applied to high density occupied spaces with special focus on school buildings. The paper shows the potential and applicability of these systems for energy savings and discusses main criteria for their adequate integration in school building designs.

  13. Case studies of scenario analysis for adaptive management of natural resource and infrastructure systems

    DEFF Research Database (Denmark)

    Hamilton, M.C.; Thekdi, S.A.; Jenicek, E.M.

    2013-01-01

    Management of natural resources and infrastructure systems for sustainability is complicated by uncertainties in the human and natural environment. Moreover, decisions are further complicated by contradictory views, values, and concerns that are rarely made explicit. Scenario analysis can play...... a major role in addressing the challenges of sustainability management, especially the core question of how to scan the future in a structured, integrated, participatory, and policy-relevant manner. In a context of systems engineering, scenario analysis can provide an integrated and timely understanding...... of emergent conditions and help to avoid regret and belated action. The purpose of this paper is to present several case studies in natural resources and infrastructure systems management where scenario analysis has been used to aide decision making under uncertainty. The case studies include several resource...

  14. Bringing together social-ecological system and territoire concepts to explore nature-society dynamics

    Directory of Open Access Journals (Sweden)

    Olivier Barreteau

    2016-12-01

    Full Text Available We examine two academic traditions that address the nature-society interface. These traditions are organized around two main concepts: social-ecological system and territoire. These traditions have grown independently and are rooted respectively in ecology and social geography. We show that they have much in common: Both come with a systemic view of the nature-society interface and have the intention of understanding better the relations between nature and society and improving their sustainability. However, they differ in how they deal with space and society. We foresee that the combination of both traditions could improve the understanding of these systems, their definition, and their evolution, and hence, the capacity to assess and manage their resilience.

  15. Coordinated Operation of the Electricity and Natural Gas Systems with Bi-directional Energy Conversion

    DEFF Research Database (Denmark)

    Zeng, Qing; Zhang, Baohua; Fang, Jiakun

    2017-01-01

    A coordinated operation of the natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables. This work focuses on the unified optimal operation of the integrated natural gas and electricity system considering the network...... constraints in both systems. An iterative method is proposed to deal with the nonlinearity in the proposed model. The models of the natural gas and power system are linearized in every iterative step. Simulation results demonstrate the effectiveness of the approach. Applicability of the proposed method...... is tested in the sample case. Finally, the effect of Power to Gas (P2G) on the daily economic dispatch is also investigated....

  16. Adaptive discontinuous Galerkin methods for non-linear reactive flows

    CERN Document Server

    Uzunca, Murat

    2016-01-01

    The focus of this monograph is the development of space-time adaptive methods to solve the convection/reaction dominated non-stationary semi-linear advection diffusion reaction (ADR) equations with internal/boundary layers in an accurate and efficient way. After introducing the ADR equations and discontinuous Galerkin discretization, robust residual-based a posteriori error estimators in space and time are derived. The elliptic reconstruction technique is then utilized to derive the a posteriori error bounds for the fully discrete system and to obtain optimal orders of convergence. As coupled surface and subsurface flow over large space and time scales is described by (ADR) equation the methods described in this book are of high importance in many areas of Geosciences including oil and gas recovery, groundwater contamination and sustainable use of groundwater resources, storing greenhouse gases or radioactive waste in the subsurface.

  17. Discontinuous phase transition in an open-ended Naming Game

    International Nuclear Information System (INIS)

    Crokidakis, Nuno; Brigatti, Edgardo

    2015-01-01

    In this work we study on a 2D square lattice a recent version of the Naming Game, an agent-based model used for describing the emergence of linguistic structures. The system is open-ended and agents can invent new words throughout the evolution of the game, picking them up from a pool characterised by a Gaussian distribution with standard deviation σ. The model displays a nonequilibrium phase transition at a critical point σ c  ≈ 25.6, which separates an absorbing consensus state from an active fragmented state where agents continuously exchange different words. The finite-size scaling analysis of our simulations strongly suggests that the phase transition is discontinuous. (paper)

  18. Proposal for an Experimental Methodology for Evaluation of Natural Lighting Systems Applied in Buildings

    Directory of Open Access Journals (Sweden)

    Anderson Diogo Spacek

    2017-07-01

    Full Text Available This work has the objective of developing a methodology for the evaluation of indoor natural lighting systems, which, with speed and practicality, provides from real conditions of use a reliable result about the quality and performance of the proposed system. The methodology is based on the construction of two real-size test environments, which will be subjected to a natural light system through reflexive tubes made from recycled material, and to a commercial system already certified and consolidated, creating the possibility of comparison. Furthermore, the data acquired in the test environments will be examined in light of the values of solar radiation obtained from a digital meteorological station, such that it is possible to stipulate the lighting capacity of the systems at different times of the year.

  19. Neural control systems for alternatively fuelled vehicles and natural gas fuel injection for DACIA NOVA

    Energy Technology Data Exchange (ETDEWEB)

    Sulatisky, M. [Saskatchewan Research Council, Saskatoon, SK (Canada); Ghelesel, A. [BC Gas International, Vancouver, BC (Canada)

    1999-07-01

    The elements of natural gas vehicle conversion technology are described as background to a discussion of the development of bi-fuel injection system for the Rumanian-manufactured DACIA-NOVA automobile. The bi-fuel injection system mirrors the fueling system installed by the original equipment manufacturer; it can also be easily installed on Ford, General Motors and DaimlerChrysler vehicles as well as on most imports.To meet emission standards after 2000, it is envisaged to install on the DACIA NOVA a neural control system (NCS) and a completely adaptive linear control system (ACLS). Details of natural gas vehicles development and the development of NCS and ACLS are discussed, including short-term and long-term objectives.

  20. Interdependency Assessment of Coupled Natural Gas and Power Systems in Energy Market

    Science.gov (United States)

    Yang, Hongzhao; Qiu, Jing; Zhang, Sanhua; Lai, Mingyong; Dong, Zhao Yang

    2015-12-01

    Owing to the technological development of natural gas exploration and the increasing penetration of gas-fired power generation, gas and power systems inevitably interact with each other from both physical and economic points of view. In order to effectively assess the two systems' interdependency, this paper proposes a systematic modeling framework and constructs simulation platforms for coupled gas and power systems in an energy market environment. By applying the proposed approach to the Australian national electricity market (NEM) and gas market, the impacts of six types of market and system factors are quantitatively analyzed, including power transmission limits, gas pipeline contingencies, gas pipeline flow constraints, carbon emission constraints, power load variations, and non-electric gas load variations. The important interdependency and infrastructure weakness for the two systems are well studied and identified. Our work provides a quantitative basis for grid operators and policy makers to support and guide operation and investment decisions for electric power and natural gas industries.

  1. Health risk assessment linked with purified biogas injection in a natural gas distribution system

    International Nuclear Information System (INIS)

    Leroux, Carole; Modelon, Hugues; Rousselle, Christophe; Zdanevitch, Isabelle; Evanno, Sebastien

    2009-06-01

    This document provides for the opinion of the French Agency for Environmental and Occupational Health and Safety (Afsset) expressed after the collective expertise carried out for the evaluation of the health risk linked with biogas injection in the natural gas distribution system. Following the recommendations issued by the Afsset, works have been started in order to collect the sludge-derived biogas and to analyse its composition. These data will be used to assess accidental risks (resulting from biogas valorisation, pipeline transport, industrial and domestic energy valorisation) as well as health risks for users (resulting from the injection in the natural gas distribution system)

  2. Static semifluxons in a long Josephson junction with π-discontinuity points

    NARCIS (Netherlands)

    Susanto, H.; van Gils, Stephanus A.; Visser, T.P.P.; Ariando, A.; Smilde, H.J.H.; Hilgenkamp, Johannes W.M.

    2003-01-01

    We investigate analytically a long Josephson junction with several $\\pi$-discontinuity points characterized by a jump of $\\pi$ in the phase difference of the junction. The system is described by a perturbed-combined sine-Gordon equation. Via phase-portrait analysis, it is shown how the existence of

  3. 78 FR 79564 - Discontinuance of Annual Financial Assessments-Delay in Implementation

    Science.gov (United States)

    2013-12-30

    ... INFORMATION: Certain veterans are enrolled in the VA health care system based on their income: Priority Groups... computer software, VA is postponing implementation of this change. FOR FURTHER INFORMATION CONTACT: Kristin... AFFAIRS Discontinuance of Annual Financial Assessments--Delay in Implementation AGENCY: Department of...

  4. Identification of rock mass discontinuities in a cluster of seismic event hypocenters.

    CSIR Research Space (South Africa)

    Kijko, A

    1999-01-01

    Full Text Available cluster is obtained. This simplified pattern might then be interpreted in terms of a fault, a system of faults or in general, as a rock mass discontinuity. The process is tested and demonstrated for three synthetic sets of data: a single fault, two joined...

  5. Passive safety systems and natural circulation in water cooled nuclear power plants

    International Nuclear Information System (INIS)

    2009-11-01

    Nuclear power produces 15% of the world's electricity. Many countries are planning to either introduce nuclear energy or expand their nuclear generating capacity. Design organizations are incorporating both proven means and new approaches for reducing the capital costs of their advanced designs. In the future most new nuclear plants will be of evolutionary design, often pursuing economies of scale. In the longer term, innovative designs could help to promote a new era of nuclear power. Since the mid-1980s it has been recognized that the application of passive safety systems (i.e. those whose operation takes advantage of natural forces such as convection and gravity), can contribute to simplification and potentially improve economics of new nuclear power plant designs. The IAEA Conference on The Safety of Nuclear Power: Strategy for the Future, which was convened in 1991, noted that for new plants 'the use of passive safety features is a desirable method of achieving simplification and increasing the reliability of the performance of essential safety functions, and should be used wherever appropriate'. Some new designs also utilize natural circulation as a means to remove core power during normal operation. The use of passive systems can eliminate the costs associated with the installation, maintenance, and operation of active systems that require multiple pumps with independent and redundant electric power supplies. However, considering the weak driving forces of passive systems based on natural circulation, careful design and analysis methods must be employed to ensure that the systems perform their intended functions. To support the development of advanced water cooled reactor designs with passive systems, investigations of natural circulation are conducted in several IAEA Member States with advanced reactor development programmes. To foster international collaboration on the enabling technology of passive systems that utilize natural circulation, the IAEA

  6. For Nature: Deep Greening World-Systems Analysis for the 21st Century

    Directory of Open Access Journals (Sweden)

    Sing S. Chew

    2015-08-01

    Full Text Available From its conception the world-systems perspective has been preoccupied with the study of long term global transformations (see for ex., Frank 1968, 1979; Wallerstein 1974; Amin 1974; Wolf, 1982; Chase-Dunn 1989; Chase-Dunn and Hall 1992; Kaplan 1978.2. To this extent, the various structural relationships, trends, and cycles of the world system have been identified to explain the processes of global transformation. The varied attempts to pinpoint and analyze these relations, trends, and cycles have been within the context of connections between humans, classes, status groups, industries, regions, and states in the world economy. From an ecological point of view (ontologically and epistemologically, such a manner of understanding change is quite anthropocentric, as global transformation necessitates a changing relationship with Nature. In an era of increasing global concern and awareness of the finite nature of natural resources and the growing realization of the contemporary losses in plant and animal species and the continued susceptibility of the human species to climatological changes and diseases despite various scientific and technological advances, we need to consider that besides social relations and structures, the basis of human reproduction includes our relationships with the non-human world (ecology. World-systems /world system analyses need to move beyond deciphering the processes of global change only through the social (anthropocentric dimension of the relations underlining these processes. Keeping to just the social relations/structures of the reproduction of the system limits the range of explanations we can provide for global transformation, and also restricts the dimensions whereby the basis for these changes can be explored. This paper is an attempt to introduce the other basic dimension (our relations with Nature into the overall equation of world-systems/world system analyses for our understanding of global change. Ultimately

  7. Discontinuation of Buprenorphine Maintenance Therapy: Perspectives and Outcomes

    Science.gov (United States)

    Bentzley, Brandon S.; Barth, Kelly S.; Back, Sudie E.; Book, Sarah W.

    2015-01-01

    Buprenorphine maintenance therapy (BMT) is increasingly the preferred opioid maintenance agent due to its reduced toxicity and availability in an office-based setting in the United States. Although BMT has been shown to be highly efficacious, it is often discontinued soon after initiation. No current systematic review has yet investigated providers’ or patients’ reasons for BMT discontinuation or the outcomes that follow. Hence, provider and patient perspectives associated with BMT discontinuation after a period of stable buprenorphine maintenance and the resultant outcomes were systematically reviewed with specific emphasis on pre-buprenorphine-taper parameters predictive of relapse following BMT discontinuation. Few identified studies address provider or patient perspectives associated with buprenorphine discontinuation. Within the studies reviewed providers with residency training in BMT were more likely to favor long term BMT instead of detoxification, and providers were likely to consider BMT discontinuation in the face of medication misuse. Patients often desired to remain on BMT because of fear of relapse to illicit opioid use if they were to discontinue BMT. The majority of patients who discontinued BMT did so involuntarily, often due to failure to follow strict program requirements, and 1 month following discontinuation, rates of relapse to illicit opioid use exceeded 50% in every study reviewed. Only lower buprenorphine maintenance dose, which may be a marker for attenuated addiction severity, predicted better outcomes across studies. Relaxed BMT program requirements and frequent counsel on the high probability of relapse if BMT is discontinued may improve retention in treatment and prevent the relapse to illicit opioid use that is likely to follow BMT discontinuation. PMID:25601365

  8. Effects of Natural Gas Compositions on CNG Fast Filling Process for Buffer Storage System

    Directory of Open Access Journals (Sweden)

    Farzaneh-Gord M.

    2013-02-01

    Full Text Available The accurate modeling of the fast-fill process occurring in Compressed Natural Gas (CNG fuelled vehicle storage cylinders is a complex process and should be thoroughly studied. Final in-cylinder conditions should meet appropriate cylinder safety standards. The composition of natural gas plays an important role on its thermodynamic properties and consequently, on the fast-fill process and the final conditions. Here, a theoretical analysis has been developed to study the effects of the natural gas composition on the filling process of an onboard Natural Gas Vehicle (NGV cylinder. The cylinder is assumed as a lumped system. The analysis is based on laws of thermodynamics and mass balance. Based on AGA8 Equation of State (EOS and thermodynamics relationships, the required properties of natural gas mixtures have been calculated. The results are presented for an adiabatic system. The results show that the compositions of natural gas have great effects on the filling process and final in-cylinder conditions. Furthermore, the gas with less methane percentage in its composition is more suitable for the filling process.

  9. Integrating human and natural systems in community psychology: an ecological model of stewardship behavior.

    Science.gov (United States)

    Moskell, Christine; Allred, Shorna Broussard

    2013-03-01

    Community psychology (CP) research on the natural environment lacks a theoretical framework for analyzing the complex relationship between human systems and the natural world. We introduce other academic fields concerned with the interactions between humans and the natural environment, including environmental sociology and coupled human and natural systems. To demonstrate how the natural environment can be included within CP's ecological framework, we propose an ecological model of urban forest stewardship action. Although ecological models of behavior in CP have previously modeled health behaviors, we argue that these frameworks are also applicable to actions that positively influence the natural environment. We chose the environmental action of urban forest stewardship because cities across the United States are planting millions of trees and increased citizen participation in urban tree planting and stewardship will be needed to sustain the benefits provided by urban trees. We used the framework of an ecological model of behavior to illustrate multiple levels of factors that may promote or hinder involvement in urban forest stewardship actions. The implications of our model for the development of multi-level ecological interventions to foster stewardship actions are discussed, as well as directions for future research to further test and refine the model.

  10. Development of a Natural Rearing System to Improve Supplemental Fish Quality, 1996-1998 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Maynard, Desmond J.

    2001-09-13

    This report covers the 1996-1998 Natural Rearing Enhancement System (NATURES) research for increasing hatchery salmon postrelease survival and producing fish with more wild-like behavior, physiology, and morphology prior to release. Experiments were conducted evaluating automatic subsurface feeders; natural diets; exercise systems; seminatural raceway habitat enriched with cover, structure, and substrate; and predator avoidance conditioning for hatchery salmonids. Automatic subsurface feed delivery systems did not affect chinook salmon depth distribution or vulnerability to avian predators. Live-food diets only marginally improved the ability of chinook salmon to capture prey in stream enclosures. A prototype exercise system that can be retrofitted to raceways was developed, however, initial testing indicated that severe amounts of exercise may increase in culture mortality. Rearing chinook salmon in seminatural raceway habitat with gravel substrate, woody debris structure, and overhead cover improved coloration and postrelease survival without impacting in-culture health or survival. Steelhead fry reared in enriched environments with structure, cover, and point source feeders dominated and outcompeted conventionally reared fish. Exposing chinook salmon to caged predators increased their postrelease survival. Chinook salmon showed an antipredator response to chemical stimuli from injured conspecifics and exhibited acquired predator recognition following exposure to paired predator-prey stimuli. The report also includes the 1997 Natural Rearing System Workshop proceedings.

  11. CONSIDERATIONS REGARDING THE INTEGRATION OF FUNDAMENTAL HUMAN RIGHTS IN THE SYSTEM OF NATURAL LAW

    Directory of Open Access Journals (Sweden)

    Claudiu Ramon D. Butculescu

    2016-11-01

    Full Text Available This article studies the relationships and interactions between fundamental human rights and natural law school. The objectives of this paper are circumscribed to the way fundamental human rights, by their nature, can be integrated within the doctrine of natural law or to the contrary, may be related to various branches of legal positivism. In specialized literature, it was pointed out that fundamental human rights constitute genuine natural rights which have the same natural law recognized attributes: immutability, non-alienable nature et. al. However, in the context of contemporary changes within the European Union, generated by cultural differences which are becoming ever more significant, the question rises of whether those rights are in fact a creation of legal positivism. Within the paperthere are several doctrine opinions described, as well as some arguments for reconsidering the placement of fundamental rights within the sphere of legal positivism. Using the comparative method, the study analyzes the common points and the points of divergence between fundamental rights and the doctrines of natural law and legal positivism, seen through the prism of the general theory of systems, legal culture, legal colonialism and legal ethnocentrism.

  12. Gas analysis modeling system forecast for the Energy Modeling Forum North American Natural Gas Market Study

    International Nuclear Information System (INIS)

    Mariner-Volpe, B.; Trapmann, W.

    1989-01-01

    The Gas Analysis Modeling System is a large computer-based model for analyzing the complex US natural gas industry, including production, transportation, and consumption activities. The model was developed and first used in 1982 after the passage of the NGPA, which initiated a phased decontrol of most natural gas prices at the wellhead. The categorization of gas under the NGPA and the contractual nature of the natural gas market, which existed at the time, were primary factors in the development of the basic structure of the model. As laws and regulations concerning the natural gas market have changed, the model has evolved accordingly. Recent increases in competition in the wellhead market have also led to changes in the model. GAMS produces forecasts of natural gas production, consumption, and prices annually through 2010. It is an engineering-economic model that incorporates several different mathematical structures in order to represent the interaction of the key groups involved in the natural gas market. GAMS has separate supply and demand components that are equilibrated for each year of the forecast by means of a detailed transaction network

  13. THE INFLUENCE OF DISCONTINUITY FABRIC AND OTHER FACTORS ON OPTIMUM EXPLOITATION OF DIMENSION STONE

    OpenAIRE

    Ivan Tomašić

    1994-01-01

    Dimension stone as a specific nonmetallic raw material, regarding deposit conditions, exploitation methods and processing, demands an adequate estimate of dimensioning i.e. opti-malizalion of the exploitation in relation to the structural elements. The analyzed and presented examples show that in natural conditions adaptation of the exploitation technology to the discontinuity fabric could result in considerable gains in utilization of rock mass in stone blocks, specialy if these blocks ar...

  14. The immune system, natural autoantibodies and general homeostasis in health and disease.

    Science.gov (United States)

    Poletaev, A; Boura, P

    2011-10-01

    It is generally accepted that the destination of the immune system is not only to discriminate between self and non-self but also to mount responses against non-self. During the last decades, it became evident that weak self-reactivity is a necessary condition for immune homeostasis. Natural self reactivity and the internal image created by autoantibodies, participate greatly to the maintenance of homeostasis. Under conditions of increased or altered antigenic pressure, the homeostatic status is disrupted and the organism becomes vulnerable to the emergence of diseases. "Immunculus" is the self-reactive and interconnected entity of the immune system, provided by a complicated network of natural autoantibobies of different specificity, as a mosaic picture. Quantitative changes in each part of the image are related to variations of expression of relative antigens. The immune system takes in account image information from the continuous screening of the antigenic status and compares between presented state and the desired (optimal) one. Substantial and prolonged deviations from the optimal state, triggers the induction of compensatory and reparative processes, aiming to restore molecular and functional homeostasis. So, natural autoimmunity through the ability of natural a-Abs to induce mechanisms of natural and acquired immunity, aims to prevent pathogenic processes and maintain or restore health status.

  15. Using natural gas generation to improve power system efficiency in China

    International Nuclear Information System (INIS)

    Hu, Junfeng; Kwok, Gabe; Xuan, Wang; Williams, James H.; Kahrl, Fredrich

    2013-01-01

    China's electricity sector faces the challenge of managing cost increases, improving reliability, and reducing its environmental footprint even as operating conditions become more complex due to increasing renewable penetration, growing peak demand, and falling system load factors. Addressing these challenges will require changes in how power generation is planned, priced, and dispatched in China. This is especially true for natural gas generation, which is likely to play an important role in power systems worldwide as a flexible generation resource. Although natural gas is commonly perceived to be economically uncompetitive with coal in China, these perceptions are based on analysis that fails to account for the different roles that natural gas generation plays in power systems—baseload, load following, and peaking generation. Our analysis shows that natural gas generation is already cost-effective for meeting peak demand in China, resulting in improved capacity factors and heat rates for coal-fired generators and lower system costs. We find that the largest barrier to using natural gas for peaking generation in China is generation pricing, which could be addressed through modest reforms to support low capacity factor generation. - Highlights: • Using gas generation as a “capacity resource” in China could have multiple benefits. • Benefits include lower total costs, improved efficiency for coal generators. • Price reforms needed to support low capacity factor generation in China

  16. Natural gas transmission and distribution model of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of Integrated Analysis and Forecasting of the Energy Information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. From 1982 through 1993, the Intermediate Future Forecasting System (IFFS) was used by the EIA for its analyses, and the Gas Analysis Modeling System (GAMS) was used within IFFS to represent natural gas markets. Prior to 1982, the Midterm Energy Forecasting System (MEFS), also referred to as the Project Independence Evaluation System (PIES), was employed. NEMS was developed to enhance and update EIA`s modeling capability by internally incorporating models of energy markets that had previously been analyzed off-line. In addition, greater structural detail in NEMS permits the analysis of a broader range of energy issues. The time horizon of NEMS is the midterm period (i.e., through 2015). In order to represent the regional differences in energy markets, the component models of NEMS function at regional levels appropriate for the markets represented, with subsequent aggregation/disaggregation to the Census Division level for reporting purposes.

  17. Natural gas transmission and distribution model of the National Energy Modeling System

    International Nuclear Information System (INIS)

    1997-02-01

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of Integrated Analysis and Forecasting of the Energy Information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. From 1982 through 1993, the Intermediate Future Forecasting System (IFFS) was used by the EIA for its analyses, and the Gas Analysis Modeling System (GAMS) was used within IFFS to represent natural gas markets. Prior to 1982, the Midterm Energy Forecasting System (MEFS), also referred to as the Project Independence Evaluation System (PIES), was employed. NEMS was developed to enhance and update EIA's modeling capability by internally incorporating models of energy markets that had previously been analyzed off-line. In addition, greater structural detail in NEMS permits the analysis of a broader range of energy issues. The time horizon of NEMS is the midterm period (i.e., through 2015). In order to represent the regional differences in energy markets, the component models of NEMS function at regional levels appropriate for the markets represented, with subsequent aggregation/disaggregation to the Census Division level for reporting purposes

  18. Discontinuities in Early Development of the Understanding of Physical Causality

    Science.gov (United States)

    Aschersleben, Gisa; Henning, Anne; Daum, Moritz M.

    2013-01-01

    Research on early physical reasoning has shown surprising discontinuities in developmental trajectories. Infants possess some skills that seem to disappear and then re-emerge in childhood. It has been suggested that prediction skills required in search tasks might cause these discontinuities (Keen, 2003). We tested 3.5- to 5-year-olds'…

  19. Enacting discontinuity-what's useful and what's cumbersome

    NARCIS (Netherlands)

    Stegmaier, Peter

    2015-01-01

    In this paper, I will review various empirical and theoretical sets of conditions and strategies under which active and purposeful discontinuity appears accomplishable. More abrupt and more incremental processes of discontinuation will be distinguished, as well as how they are linked to different

  20. Discontinuous Galerkin finite element methods for hyperbolic differential equations

    NARCIS (Netherlands)

    van der Vegt, Jacobus J.W.; van der Ven, H.; Boelens, O.J.; Boelens, O.J.; Toro, E.F.

    2002-01-01

    In this paper a suryey is given of the important steps in the development of discontinuous Galerkin finite element methods for hyperbolic partial differential equations. Special attention is paid to the application of the discontinuous Galerkin method to the solution of the Euler equations of gas

  1. Qualitative study of reasons for discontinuation of injectable ...

    African Journals Online (AJOL)

    Discontinuation of contraception is a major problem in Kenya. Even though they want to space or limit their births, over a quarter of contraceptive injectable users discontinue use of the method within 12 months of beginning use. Fourteen focus group discussions were conducted in Nyando District, Kenya among current ...

  2. 27 CFR 25.277 - Discontinuance of operations.

    Science.gov (United States)

    2010-04-01

    ... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Pilot Brewing Plants § 25.277 Discontinuance of operations. When operations of a pilot brewing plant are to be discontinued, the operator shall notify the... operations have been completed and all beer at the premises has been disposed of and accounted for, the...

  3. Discontinuous pn-heterojunction for organic thin film transistors

    NARCIS (Netherlands)

    Cho, B.; Yu, S.H.; Kim, M.; Lee, M.H.; Huh, W.; Lee, J.; Kim, J.; Cho, J.H.; Lee, J.Y.; Song, Y.J.; Kang, M.S.

    2014-01-01

    Utilization of discontinuous pn-oragnic heterojunction is introduced as a versatile method to improve charge transport in organic thin film transistors (OTFTs). The method is demonstrated by depositing n-type dioctyl perylene tetracarboxylic diimide (PTCDI-C8) discontinuously onto base p-type

  4. 27 CFR 21.3 - Stocks of discontinued formulas.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Stocks of discontinued..., DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM General Provisions § 21.3 Stocks of discontinued formulas. Denaturers, or specially denatured spirits dealers or users, having on hand stocks of...

  5. The 1D Richards' equation in two layered soils: a Filippov approach to treat discontinuities

    Science.gov (United States)

    Berardi, Marco; Difonzo, Fabio; Vurro, Michele; Lopez, Luciano

    2018-05-01

    The infiltration process into the soil is generally modeled by the Richards' partial differential equation (PDE). In this paper a new approach for modeling the infiltration process through the interface of two different soils is proposed, where the interface is seen as a discontinuity surface defined by suitable state variables. Thus, the original 1D Richards' PDE, enriched by a particular choice of the boundary conditions, is first approximated by means of a time semidiscretization, that is by means of the transversal method of lines (TMOL). In such a way a sequence of discontinuous initial value problems, described by a sequence of second order differential systems in the space variable, is derived. Then, Filippov theory on discontinuous dynamical systems may be applied in order to study the relevant dynamics of the problem. The numerical integration of the semidiscretized differential system will be performed by using a one-step method, which employs an event driven procedure to locate the discontinuity surface and to adequately change the vector field.

  6. Achieving structured colour in inorganic systems: Learning from the natural world

    Science.gov (United States)

    Withnall, R.; Silver, J.; Ireland, T. G.; Zhang, S.; Fern, G. R.

    2011-03-01

    Structural colour is observed in a number of naturally occurring minerals such as labradorite, bornite, hematite and ammolite, in addition to the well-known example of opal, the semi-precious gemstone. The origin of the structural colour is examined for these inorganic systems using electron microscopy to obtain structural information on the nanoscale. The structural colour that is observed in natural inorganic systems can be mimicked in synthetic inorganic systems, as exemplified by the synthetic opals reported herein. These systems exhibit stop bands, i.e. wavelength regions in which visible light cannot propagate, which show a shift in their wavelength location when the angle of the incident light is varied. When light-emitting phosphors and dyes are incorporated into the opal structures, their emission spectra are modified when the stop bands of the opals overlap the emission bands of the light-emitting materials.

  7. Natural disaster risk analysis for critical infrastructure systems: An approach based on statistical learning theory

    International Nuclear Information System (INIS)

    Guikema, Seth D.

    2009-01-01

    Probabilistic risk analysis has historically been developed for situations in which measured data about the overall reliability of a system are limited and expert knowledge is the best source of information available. There continue to be a number of important problem areas characterized by a lack of hard data. However, in other important problem areas the emergence of information technology has transformed the situation from one characterized by little data to one characterized by data overabundance. Natural disaster risk assessments for events impacting large-scale, critical infrastructure systems such as electric power distribution systems, transportation systems, water supply systems, and natural gas supply systems are important examples of problems characterized by data overabundance. There are often substantial amounts of information collected and archived about the behavior of these systems over time. Yet it can be difficult to effectively utilize these large data sets for risk assessment. Using this information for estimating the probability or consequences of system failure requires a different approach and analysis paradigm than risk analysis for data-poor systems does. Statistical learning theory, a diverse set of methods designed to draw inferences from large, complex data sets, can provide a basis for risk analysis for data-rich systems. This paper provides an overview of statistical learning theory methods and discusses their potential for greater use in risk analysis

  8. Natural gas pricing reform in China: Getting closer to a market system?

    International Nuclear Information System (INIS)

    Paltsev, Sergey; Zhang, Danwei

    2015-01-01

    Recent policy in China targets an increase in the contribution of natural gas to the nation's energy supply. Historically, China's natural gas prices have been highly regulated with a goal to protect consumers. The old pricing regime failed to provide enough incentives for natural gas suppliers, which often resulted in natural gas shortage. A new gas pricing reform was tested in Guangdong and Guangxi provinces in 2011, and introduced nationwide in 2013. The reform is aimed at creating a more market-based pricing mechanism. We show that a substantial progress toward a better predictability and transparency of prices has been made. The prices are now more connected with the international fuel oil and liquid petroleum gas prices. The government's approach for a temporary two-tier pricing when some volumes are still traded at old prices reduced a potential opposition during the new regime implementation. Some limitations of the natural gas pricing remain as it created biased incentives for producers and favors large natural gas suppliers. The pricing reform at its current stage falls short of establishing a complete market mechanism driven by an interaction of supply and demand of natural gas in China. - Highlights: • China's reform of natural gas pricing is in effect nationwide from 2013. • Prices are now connected to international fuel oil and liquid petroleum gas prices. • The reform benefits domestic producers and importers of natural gas. • There are still price distortions between industrial and residential sector. • The reform needs to create a system where both supply and demand are considered.

  9. Anterior segment optical coherence tomography changes with introduction and discontinuation of tamsulosin.

    Science.gov (United States)

    Al-Kharashi, Abdullah; Azimzadeh, Amir A; Leung, Jerry; Radomski, Sidney; Radomski, Lenny; Lam, Wai-Ching

    2016-01-01

    The aim of this study was to quantify changes and reversibility in pupil dilation and iris dilator muscle region thickness associated with introduction and subsequent discontinuation of tamsulosin in patients naïve to this drug with the aid of an anterior OCT system. The study was carried out on 7 patients (14 eyes) naïve to tamsulosin and with benign prostatic hypertrophy (BHP). Measurements taken by Vistante OCT were done pre- and post-dilation of the following: pupil size, iris dilator muscle region (DMR) thickness, sphincter muscle region (SMR) thickness, and anterior chamber depth. These measurement were taken at Day 0 (tamsulosin naive), Day 30 (after one month of tamsulosin, the treatment period) and day 60 (after one month of no tamsulosin, the discontinuation period). Post-dilation pupil diameter significantly increased during the discontinuation period ( P  = 0.047). Iris DMR thickness measurements post-dilation significantly decreased during treatment ( P  = 0.00044), discontinuation (0.00011), and combined periods ( P  = 0.000050). Anterior chamber depth measurements in post-dilation were significantly decreased during treatment ( P  = 0.0016), discontinuation ( P  = 0.017), and combined periods ( P  = 0.00022). Tamsulosin discontinuation effectively increases dilated pupil size, a measure that has been inversely linked to IFIS incidence pre-operatively. Decreased DMR thickness in this short term likely illustrates changes aside from atrophy, such as vascular changes. Decreased anterior chamber depths suggest aqueous humor production is decreased as well.

  10. Undulative induction electron accelerator for the waste and natural water purification systems

    CERN Document Server

    Kulish, Victor V; Gubanov, I V

    2001-01-01

    The project analysis of Undulative Induction Accelerator (EH - accelerator) for the waste and natural water purification systems is accomplished. It is shown that the use of the four-channel design of induction block and the standard set of auxiliary equipment (developed earlier for the Linear Induction Accelerators - LINACs) allow to construct commercially promising purification systems. A quality analysis of the accelerator is done and the optimal parameters are chosen taking into account the specific sphere of its usage.

  11. Applying a Methodological Approach to the Development of a Natural Interaction System

    Science.gov (United States)

    Del Valle-Agudo, David; Rivero-Espinosa, Jessica; Calle-Gómez, Francisco Javier; Cuadra-Fernández, Dolores

    This work describes the methodology used to design a Natural Interaction System for guiding services. A national research project was the framework where the approach was applied. The aim of that system is interacting with clients of a hotel for providing diverse services. Apart from the description of the methodology, a case study is added to the paper in order to outline strengths of the approach, and limits that should lead to future research.

  12. Experimental analysis on a novel solar collector system achieved by supercritical CO2 natural convection

    International Nuclear Information System (INIS)

    Chen, Lin; Zhang, Xin-Rong

    2014-01-01

    Highlights: • Supercritical CO 2 flow is proposed for natural circulation solar water heater system. • Experimental system established and consists of supercritical fluid high pressure side and water side. • Stable supercritical CO 2 natural convective flow is well induced and water heating process achieved. • Seasonal solar collector system efficiency above 60% achieved and optimization discussed. - Abstract: Solar collector has become a hot topic both in scientific research and engineering applications. Among the various applications, the hot water supply demand accounts for a large part of social energy consumption and has become one promising field. The present study deals with a novel solar thermal conversion and water heater system achieved by supercritical CO 2 natural circulation. Experimental systems are established and tested in Zhejiang Province (around N 30.0°, E 120.6°) of southeast China. The current system is designed to operate in the supercritical region, thus the system can be compactly made and achieve smooth high rate natural convective flow. During the tests, supercritical CO 2 pipe flow with Reynolds number higher than 6700 is found. The CO 2 fluid temperature in the heat exchanger can be as high as 80 °C and a stable supply of hot water above 45 °C is achieved. In the seasonal tests, relative high collector efficiency generally above 60.0% is obtained. Thermal and performance analysis is carried out with the experiment data. Comparisons between the present system and previous solar water heaters are also made in this paper

  13. Evolution of nitrate level in green lettuce conventional grown under natural conditions and aquaponic system

    OpenAIRE

    Flavius Blidariu; Drasovean Alexandru; Grozea Adrian; Radulov Isidora; Lalescu Dacian

    2013-01-01

    Aquaponics integrates growing plants without soil technology with aquaculture, having an important role in recovery of nutrients from effluents. The research aimed to evaluate nitrates level in lettuce (Lactuca sativa) conventional grown under natural conditions and in integrated aquaponic system with a recirculated aquaculture system designed for pikeperch growth (Sander lucioperca). Conventional production (54 plants) has been obtained in the field without fertilizer or pesticide management...

  14. Changes to the oil and natural gas royalty system: Technical detail and financial impact

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This document describes the changes to the oil and natural gas royalty system and the structure of the new royalty formulas for new and old gas, third-tier oil, new and old oil, reactivated, low productivity and horizontal re-entry oil wells, and experimental oilsands. A summary of the future oil and gas royalty system, and its financial impact on government and producers are also included. Background information is also included.

  15. The Evolution and Nature of School Accountability in the Singapore Education System

    Science.gov (United States)

    Ng, Pak Tee

    2010-01-01

    This paper describes and examines the nature and evolution of school accountability in the Singapore Education System. In particular, the different facets of school accountability are examined through a theoretical framework comprising four relatively distinct concepts of accountability as performance reporting; as a technical process; as a…

  16. Nouns referring to tools and natural objects differentially modulate the motor system.

    Science.gov (United States)

    Gough, Patricia M; Riggio, Lucia; Chersi, Fabian; Sato, Marc; Fogassi, Leonardo; Buccino, Giovanni

    2012-01-01

    While increasing evidence points to a critical role for the motor system in language processing, the focus of previous work has been on the linguistic category of verbs. Here we tested whether nouns are effective in modulating the motor system and further whether different kinds of nouns - those referring to artifacts or natural items, and items that are graspable or ungraspable - would differentially modulate the system. A Transcranial Magnetic Stimulation (TMS) study was carried out to compare modulation of the motor system when subjects read nouns referring to objects which are Artificial or Natural and which are Graspable or Ungraspable. TMS was applied to the primary motor cortex representation of the first dorsal interosseous (FDI) muscle of the right hand at 150 ms after noun presentation. Analyses of Motor Evoked Potentials (MEPs) revealed that across the duration of the task, nouns referring to graspable artifacts (tools) were associated with significantly greater MEP areas. Analyses of the initial presentation of items revealed a main effect of graspability. The findings are in line with an embodied view of nouns, with MEP measures modulated according to whether nouns referred to natural objects or artifacts (tools), confirming tools as a special class of items in motor terms. Additionally our data support a difference for graspable versus non graspable objects, an effect which for natural objects is restricted to initial presentation of items. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Four Complete Datatype Defining Rewrite Systems for an Abstract Datatype of Natural Numbers

    NARCIS (Netherlands)

    Bergstra, J.A.

    2014-01-01

    Natural numbers with zero, one, successor, addition and multiplication, constitute a classic example of an abstract datatype amenable for equational initial algebra specification. Datatype defining rewrite systems provide a specification which at the same time is a complete, that is confluent and

  18. Assessing impacts of payments for watershed services on sustainability in coupled human and natural systems

    Science.gov (United States)

    Heidi Asbjornsen; Alex S. Mayer; Kelly W. Jones; Theresa Selfa; Leonardo Saenz; Randall K. Kolka; Kathleen E. Halvorsen

    2015-01-01

    Payments for watershed services (PWS) as a policy tool for enhancing water quality and supply have gained momentum in recent years, but their ability to lead to sustainable watershed outcomes is uncertain. Consequently, the demand for effective monitoring and evaluation (M&E) of PWS impacts on coupled human and natural systems (CHANS) and their implications for...

  19. 75 FR 18607 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems

    Science.gov (United States)

    2010-04-12

    ... complex as climate change (e.g. indirect emissions from electricity use). In that sense, one could view... vented carbon dioxide (CO 2 ) and methane (CH 4 ) emissions from petroleum and natural gas systems... 2 emissions in the petroleum and gas industry, while significantly reducing industry burden. Under...

  20. The effect of hospitalist discontinuity on adverse events.

    Science.gov (United States)

    O'Leary, Kevin J; Turner, Jonathan; Christensen, Nicholas; Ma, Madeleine; Lee, Jungwha; Williams, Mark V; Hansen, Luke O

    2015-03-01

    Patient-physician continuity is difficult to achieve in hospital settings because of the need to provide care continuously. The impact of hospital physician discontinuity on patient safety is unknown. To determine the association between hospital physician continuity and the incidence of adverse events (AEs). Retrospective observational study using multivariable models to adjust for patient characteristics. Patients admitted to a nonteaching hospitalist service in a large academic hospital between March 1, 2009 and December 31, 2011. Two measures of continuity were used. The Number of Physicians Index (NPI) was the total number of unique hospitalists caring for a patient. The Usual Provider of Care (UPC) Index was the proportion of encounters with the most frequently encountered hospitalist. Outcome measures were AEs detected by automated queries of information systems and confirmed by 2 physician researchers. Our analysis included data from 474 hospitalizations. In unadjusted models, each 1-unit increase in the NPI (ie, less continuity) was significantly associated with the incidence of 1 or more AEs (odds ratio = 1.75; P < 0.001). However, UPC was not associated with incidence of AEs. Across all adjusted models, neither NPI nor UPC was significantly associated with the incidence of AEs. The direction of the effect of discontinuity on AEs was also inconsistent across models. Hospitalist physician continuity does not appear to be associated with the incidence of AEs. Because hospital care is provided by teams of clinicians, future research should evaluate the impact of team complexity and dynamics on patient outcomes. © 2014 Society of Hospital Medicine.

  1. Discontinuities in a damped quantum harmonic oscillator

    International Nuclear Information System (INIS)

    Giraldi, Filippo; Petruccione, Francesco

    2012-01-01

    The quantum model for a damped harmonic oscillator linearly coupled to a reservoir of continuous frequency modes has been exactly diagonalized either with or without the rotating wave approximation. The exact dynamics, formally described in terms of the coupling function, is analyzed for the Drude model. In this scenario, we focus on a class of couplings recovering the Drude form as a limiting case. The exact time evolution of the expectation values of the position, momentum and number operators are described through Fox H-functions, as well as the correlation function of the reservoir. In correspondence with the critical values of the frequency, discontinuities appear in the long time scale dynamics, arbitrarily slowing down the relaxations of the above observables. This effect allows one to enhance arbitrarily the lifetime of the excitations, giving relevant applications in the study of the quantum domain of opto-mechanical and nano-mechanical resonators. The critical frequency approach constitutes a further method of control in the scenario of environment-induced decoherence via reservoir engineering. (paper)

  2. The Nature of Living Systems: An Exposition of the Basic Concepts in General Systems Theory.

    Science.gov (United States)

    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…

  3. The relationship between nature-based tourism and autonomic nervous system function among older adults.

    Science.gov (United States)

    Chang, Liang-Chih

    2014-01-01

    Nature-based tourism has recently become a topic of interest in health research. This study was aimed at examining relationships among nature-based tourism, stress, and the function of the autonomic nervous system (ANS). Three hundred and twenty-two older adults living in Taichung City, Taiwan, were selected as participants. Data were collected by a face-to-face survey that included measures of the frequency of participation in domestic and international nature-based tourism and the stress and ANS function of these participants. The data were analyzed using a path analysis. The results demonstrated that the frequency of participation in domestic nature-based tourism directly contributed to ANS function and that it also indirectly contributed to ANS function through stress reduction. Domestic nature-based tourism can directly and indirectly contribute to ANS function among older adults. Increasing the frequency of participation in domestic nature-based tourism should be considered a critical element of health programs for older adults. © 2014 International Society of Travel Medicine.

  4. Developing natural resource models using the object modeling system: feasibility and challenges

    Directory of Open Access Journals (Sweden)

    L. R. Ahuja

    2005-01-01

    Full Text Available Current challenges in natural resource management have created demand for integrated, flexible, and easily parameterized hydrologic models. Most of these monolithic models are not modular, thus modifications (e.g., changes in process representation require considerable time, effort, and expense. In this paper, the feasibility and challenges of using the Object Modeling System (OMS for natural resource model development will be explored. The OMS is a Java-based modeling framework that facilitates simulation model development, evaluation, and deployment. In general, the OMS consists of a library of science, control, and database modules and a means to assemble the selected modules into an application-specific modeling package. The framework is supported by data dictionary, data retrieval, GIS, graphical visualization, and statistical analysis utility modules. Specific features of the OMS that will be discussed include: 1 how to reduce duplication of effort in natural resource modeling; 2 how to make natural resource models easier to build, apply, and evaluate; 3 how to facilitate long-term maintainability of existing and new natural resource models; and 4 how to improve the quality of natural resource model code and ensure credibility of model implementations. Examples of integrating a simple water balance model and a large monolithic model into the OMS will be presented.

  5. A System Dynamics Analysis of Investment, Technology and Policy that Affect Natural Gas Exploration and Exploitation in China

    OpenAIRE

    Xiao, Jianzhong; Cheng, Jinhua; Shen, Jun; Wang, Xiaolin

    2017-01-01

    Natural gas has an increasing role in Chinese energy transformation. We present a system dynamics model of the natural gas industry in China. A new system dynamics model for natural gas companies based on reserve exploration and well construction as well as investment dynamics is proposed. The contribution of the paper is to analyze the influence of technology, investment and policy factors on the natural gas industry. We found that the dynamics of the main variables, including gas policy, co...

  6. Natural gas markets and the creation of an export gas pipeline system in Eastern Russia

    International Nuclear Information System (INIS)

    Saneev, B.G.; Sokolov, A.D.; Popov, S.P.

    2003-01-01

    The world natural gas markets are analysed, with a special focus on the countries of Northeast Asia (NEA). The natural gas demands of China, Japan and South Korea, until the year 2020, is projected, considering a possible share of Russian gas. The resource potential of natural gas from the Siberian platform and the Sakhalin shelf is given as a sound basis for fuelling Russia's position in the natural gas market of NEA countries. Development of the powerful gas industry in the East of Russia faces some particular conditions that can decrease the effectiveness of investments. The eastern geopolitical direction is very important for Russia and the necessity to create a favourable political and economic environment for oil and gas export is of prime interest, as stressed in Energy Strategy for Russia till the Year 2020. In this context, the long-term market for natural gas in East Siberia and the Far East of Russia is investigated. Possible routes of natural gas export from Russia to NEA countries include three main directions: to the west of China with connection to the 'West-East gas pipeline', a route through and/or round Mongolia and, finally, a route along the Trans-Siberian or Baikal-Amur railroads to Russian ports in the Far East. As a result of complex studies, three stages in the creation of the unified gas pipeline system are suggested. Evaluation of the investments required for construction of such a natural gas pipeline system, expected gas volumes and prices on the markets show its high economic efficiency. In conclusion, the most valuable ideas are stressed. (author)

  7. Numerical solution of the Neutron Transport Equation using discontinuous nodal methods at X-Y geometry

    International Nuclear Information System (INIS)

    Delfin L, A.

    1996-01-01

    The purpose of this work is to solve the neutron transport equation in discrete-ordinates and X-Y geometry by developing and using the strong discontinuous and strong modified discontinuous nodal finite element schemes. The strong discontinuous and modified strong discontinuous nodal finite element schemes go from two to ten interpolation parameters per cell. They are describing giving a set D c and polynomial space S c corresponding for each scheme BDMO, RTO, BL, BDM1, HdV, BDFM1, RT1, BQ and BDM2. The solution is obtained solving the neutron transport equation moments for each nodal scheme by developing the basis functions defined by Pascal triangle and the Legendre moments giving in the polynomial space S c and, finally, looking for the non singularity of the resulting linear system. The linear system is numerically solved using a computer program for each scheme mentioned . It uses the LU method and forward and backward substitution and makes a partition of the domain in cells. The source terms and angular flux are calculated, using the directions and weights associated to the S N approximation and solving the angular flux moments to find the effective multiplication constant. The programs are written in Fortran language, using the dynamic allocation of memory to increase efficiently the available memory of the computing equipment. (Author)

  8. Discontinuities concentrate mobile predators: Quantifying organism-environment interactions at a seascape scale

    Science.gov (United States)

    Kennedy, Christina G.; Mather, Martha E.; Smith, Joseph M.; Finn, John T.; Deegan, Linda A.

    2016-01-01

    Understanding environmental drivers of spatial patterns is an enduring ecological problem that is critical for effective biological conservation. Discontinuities (ecologically meaningful habitat breaks), both naturally occurring (e.g., river confluence, forest edge, drop-off) and anthropogenic (e.g., dams, roads), can influence the distribution of highly mobile organisms that have land- or seascape scale ranges. A geomorphic discontinuity framework, expanded to include ecological patterns, provides a way to incorporate important but irregularly distributed physical features into organism–environment relationships. Here, we test if migratory striped bass (Morone saxatilis) are consistently concentrated by spatial discontinuities and why. We quantified the distribution of 50 acoustically tagged striped bass at 40 sites within Plum Island Estuary, Massachusetts during four-monthly surveys relative to four physical discontinuities (sandbar, confluence, channel network, drop-off), one continuous physical feature (depth variation), and a geographic location variable (region). Despite moving throughout the estuary, striped bass were consistently clustered in the middle geographic region at sites with high sandbar area, close to channel networks, adjacent to complex confluences, with intermediate levels of bottom unevenness, and medium sized drop-offs. In addition, the highest striped bass concentrations occurred at sites with the greatest additive physical heterogeneity (i.e., where multiple discontinuities co-occurred). The need to incorporate irregularly distributed features in organism–environment relationships will increase as high-quality telemetry and GIS data accumulate for mobile organisms. The spatially explicit approach we used to address this challenge can aid both researchers who seek to understand the impact of predators on ecosystems and resource managers who require new approaches for biological conservation.

  9. Energy performance of supermarket refrigeration and air conditioning integrated systems working with natural refrigerants

    International Nuclear Information System (INIS)

    Cecchinato, Luca; Corradi, Marco; Minetto, Silvia

    2012-01-01

    The current trends in commercial refrigeration aim at reducing the synthetic refrigerant charge, either by minimising the internal volume of the circuit or by utilising natural refrigerants, and at energy saving. The energy efficiency of supermarkets can be improved by optimising components design, recovering thermal and refrigerating energy, adopting innovative technology solutions, integrating the HVAC system with medium temperature and low temperature refrigeration plants and, finally, reducing thermal loads on refrigerated cases. This study aims at investigating the performance of different lay-out and technological solutions where only natural refrigerants are used and at finding the potential for improving energy efficiency over the traditional systems in different climates. In the analysis, chillers and heat pumps working with ammonia or propane, medium temperature systems working with ammonia or propane and carbon dioxide as heat transfer fluid or with carbon dioxide as the refrigerant and low temperature systems working with carbon dioxide are considered and benchmarked with a state-of-the-art HFCs based plant. The most efficient investigated solution enables an annual energy saving higher than 15% with respect to the baseline solution for all the considered climates. - Highlights: ► Different natural refrigerants supermarket HVAC and R integrated systems are analysed. ► Some of the proposed solutions offer a significant benefit over the baseline one. ► Up to 18.7% energy saving is achieved in the considered climates. ► The refrigeration unit condensation by the AC chiller offers the poorest results.

  10. Fractal reactor: An alternative nuclear fusion system based on nature's geometry

    International Nuclear Information System (INIS)

    Siler, T. L.

    2007-01-01

    The author presents his concept of the Fractal Reactor, which explores the possibility of building a plasma fusion power reactor based on the real geometry of nature [fractals], rather than the virtual geometry that Euclid postulated around 330 BC; nearly every architect of our plasma fusion devices has been influenced by his three-dimensional geometry. The idealized points, lines, planes, and spheres of this classical geometry continue to be used to represent the natural world and to describe the properties of all geometrical objects, even though they neither accurately nor fully convey nature's structures and processes. The Fractal Reactor concept contrasts the current containment mechanisms of both magnetic and inertial containment systems for confining and heating plasmas. All of these systems are based on Euclidean geometry and use geometrical designs that, ultimately, are inconsistent with the Non-Euclidean geometry and irregular, fractal forms of nature (3). The author explores his premise that a controlled, thermonuclear fusion energy system might be more effective if it more closely embodies the physics of a star

  11. Global early warning systems for natural hazards: systematic and people-centred.

    Science.gov (United States)

    Basher, Reid

    2006-08-15

    To be effective, early warning systems for natural hazards need to have not only a sound scientific and technical basis, but also a strong focus on the people exposed to risk, and with a systems approach that incorporates all of the relevant factors in that risk, whether arising from the natural hazards or social vulnerabilities, and from short-term or long-term processes. Disasters are increasing in number and severity and international institutional frameworks to reduce disasters are being strengthened under United Nations oversight. Since the Indian Ocean tsunami of 26 December 2004, there has been a surge of interest in developing early warning systems to cater to the needs of all countries and all hazards.

  12. Monitoring of good practices programs and independence for electricity and natural gas system operators. Report 2012

    International Nuclear Information System (INIS)

    2013-09-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 8. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2012. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2012 and audits carried out by the CRE services in these companies in 2012

  13. Teleology and randomness in the development of natural sciences research: systems, ontology and evolution

    Directory of Open Access Journals (Sweden)

    Paulo Pereira Martins Júnior

    2011-12-01

    Full Text Available This is an investigation on the subject of  Teleology, which has been dealt with all along the history of the human thought with special emphasis to the interval related to the development of scientific theories referring to the study of Nature.  The presentation of the subject starts with the conceptual definitions of Teleology. Following, this subject is revisited all along the historical application of the concept in the development of science. In this respect, the first approach is about teleology in Biology and life sciences, with emphasis on the repercussion over the vitalist conception and natural selection.  Hence, the discussion turns around the dialectic conceptions of teleological systems and random systems. Finally, this paper finishes with a thought about how these themes may be pertinent within the environmental studies whereon physical, biological and human systems are in co-operation, with the various applications of nuances and uses of the teleological concept.

  14. Monitoring of good practices programs and independence for electricity and natural gas system operators. 2010 report

    International Nuclear Information System (INIS)

    2011-01-01

    Electricity and natural gas transmission system operators (TSO) and distribution system operators (DSO) are regulated operators that provide public service functions for the benefit of the network users and the consumers they serve. Accordingly, European and French law requires that they be under independent and nondiscriminatory obligations. In particular, they must develop a good practices program which includes a range of measures to prevent the risk of discriminatory practices in network access. Pursuant to Article L.134-15 of the Energy Code, the Energy Regulatory Commission (CRE) is publishing this year its 6. annual report on the monitoring of good practices programs and independence for electricity and natural gas system operators for the year 2010. This report is based on analysis of the 'reports on the implementation of good practices programs' submitted to the CRE by the operators in late 2010 and audits carried out by the CRE services in these companies in 2010

  15. Impact, adaptation and vulnerability of natural and human systems in Europe

    International Nuclear Information System (INIS)

    Martin, Eric; Salas y Melia, David; Delire, Christine; Lemonsu, Aude; Masson, Valery; Badeau, Vincent; Gattuso, Jean-Pierre; Pigeon, Gregoire; Regimbeau, Mathieu; Viguie, Vincent

    2015-01-01

    This article analyses the observed and projected impacts of climate change on human and natural systems, their vulnerability and adaptation options. It provides insight into the main results related to hydrology, agriculture, natural ecosystems, transport, energy, tourism, infrastructures, health and social aspects. This article presents the main results concerning Europe that were compiled in the contribution of Working Group II to the IPCC fifth assessment report published in 2014. Several studies focused on mainland France are also presented, without claiming to be exhaustive. (authors)

  16. [New polymer-drug systems based on natural and synthetic polymers].

    Science.gov (United States)

    Racoviţă, Stefania; Vasiliu, Silvia; Foia, Liliana

    2010-01-01

    The great versatility of polymers makes them very useful in the biomedical and pharmaceutical fields. The combination of natural and synthetic polymers leads to new materials with tailored functional properties. The aim of this work consists in the preparation of new drug delivery system based on chitosan (natural polymer) and polybetaines (synthetic polymers), by a simple process, well known in the literature as complex coacervation methods. Also, the adsorption and release studies of two antibiotics as well as the preservation of their bactericidal capacities were performed.

  17. A new nasal drug delivery system for Diazepam using natural Mucoadhesive Polysaccharide obtained from tamarind seeds

    International Nuclear Information System (INIS)

    Datta, R.; Bandyopadhyaya, Amal K.

    2006-01-01

    A new nasal drug delivery system of diazepam has been developed with a natural mucoadhesive agent from Tamarindus indica L. The mucoadhesive strength, viscosity and gelling property of this natural mucoadhesive agent was found to be higher in comparison to synthetic polymers, hydroxyl propyl methyl cellulose (HPMC) and carbopol 934 which are conventionally used for similar purpose. In vitro drug release characteristic through franz-diffusion cell using excised bovine nasal membrane was also found to be better in comparison to the above synthetic polymers. This patient friendly, needle free dosage form may replace the diazepam injections in future. (author)

  18. Simplifying and upscaling water resources systems models that combine natural and engineered components

    Science.gov (United States)

    McIntyre, N.; Keir, G.

    2014-12-01

    Water supply systems typically encompass components of both natural systems (e.g. catchment runoff, aquifer interception) and engineered systems (e.g. process equipment, water storages and transfers). Many physical processes of varying spatial and temporal scales are contained within these hybrid systems models. The need to aggregate and simplify system components has been recognised for reasons of parsimony and comprehensibility; and the use of probabilistic methods for modelling water-related risks also prompts the need to seek computationally efficient up-scaled conceptualisations. How to manage the up-scaling errors in such hybrid systems models has not been well-explored, compared to research in the hydrological process domain. Particular challenges include the non-linearity introduced by decision thresholds and non-linear relations between water use, water quality, and discharge strategies. Using a case study of a mining region, we explore the nature of up-scaling errors in water use, water quality and discharge, and we illustrate an approach to identification of a scale-adjusted model including an error model. Ways forward for efficient modelling of such complex, hybrid systems are discussed, including interactions with human, energy and carbon systems models.

  19. Using systems gaming to explore decision-making under uncertainty in natural hazard crises

    Science.gov (United States)

    McCaughey, Jamie W.; Finnigan, David

    2017-04-01

    Faced with uncertain scientific forecasts of a potential hazard, it is perhaps natural to wait and see. As we wait, uncertainties do decrease, but so do our options to minimise impacts of the hazard. This tradeoff is fundamental to preparing for natural hazards, yet difficult to communicate. Interactive systems gaming is one promising way forward. We are developing in-person interactive games, drawing on role-playing and other table-top scenario exercises in natural hazards, as well as on game-based modeling of complex systems. Our games model an unfolding natural hazard crisis (such as volcanic unrest or an approaching typhoon) as a complex social-physical system. Participants take on the roles of diverse stakeholder groups (including government, scientists, media, farmers, city residents, and others) with differing expertise, responsibilities, and priorities. Interactions among these groups play out in a context of decreasing scientific uncertainty and decreasing options for actions to reduce societal risk. Key design challenges are (1) to engage players without trivialising the real-world context; (2) to provide the right level of guidance for players to navigate the system; and (3) to enable players to face realistic tradeoffs and see realistic consequences of their choices, without feeling frustrated that the game is set up for them to fail. We will first prototype the games with general public and secondary-school participants, then adjust this for specialist groups working in disaster management. We will illustrate participatory systems gaming techniques in our presentation 'A toolkit of systems gaming techniques' in the companion EGU session EOS6: 'Perform! A platform to discuss art & science projects with live presentation'.

  20. Knowledge acquisition from natural language for expert systems based on classification problem-solving methods

    Science.gov (United States)

    Gomez, Fernando

    1989-01-01

    It is shown how certain kinds of domain independent expert systems based on classification problem-solving methods can be constructed directly from natural language descriptions by a human expert. The expert knowledge is not translated into production rules. Rather, it is mapped into conceptual structures which are integrated into long-term memory (LTM). The resulting system is one in which problem-solving, retrieval and memory organization are integrated processes. In other words, the same algorithm and knowledge representation structures are shared by these processes. As a result of this, the system can answer questions, solve problems or reorganize LTM.

  1. Systemic functional grammar in natural language generation linguistic description and computational representation

    CERN Document Server

    Teich, Elke

    1999-01-01

    This volume deals with the computational application of systemic functional grammar (SFG) for natural language generation. In particular, it describes the implementation of a fragment of the grammar of German in the computational framework of KOMET-PENMAN for multilingual generation. The text also presents a specification of explicit well-formedness constraints on syntagmatic structure which are defined in the form of typed feature structures. It thus achieves a model of systemic functional grammar that unites both the strengths of systemics, such as stratification, functional diversification

  2. Energy Performance of a Novel System Combining Natural Ventilation with Diffuse Ceiling Inlet and Thermally Activated Building Systems (TABS)

    DEFF Research Database (Denmark)

    Yu, Tao

    . Both steady-state and dynamic measurements are carried out in the experimental chamber to investigate the energy performance of the system and the thermal comfort in the test room. Overall, this integrated system has high energy saving potential without any compromise of thermal comfort even in extreme...... and thermally activated building systems (TABS) for cooling and ventilation in future Danish office buildings. The new solution would have the special potential of using natural ventilation all year round even in the extremely cold seasons without any draught risk. The main focuses of this study are the energy...

  3. Dynamic response of underground openings in discontinuous rock

    International Nuclear Information System (INIS)

    Asmis, H.W.

    1984-02-01

    This report examines the behaviour of underground openings in discontinuous rock in response to seismic waves associated with either earthquakes or rock bursts. A literature search revealed that well-constructed underground structures, such as would be expected for nuclear fuel waste disposal vaults, underground pumped-storage or nuclear plants, have an extremely high resistance to damage from seismic motion. To complement these qualitative results, it was necessary to examine the basic mechanisms of the entire progression of seismic motion, from wave generation and propagation, to wave interaction with the underground opening. From these investigations, it was found that unless a seismic event occurs very close to the installation, the stresses generated will be low with respect to the excavation stresses, because high stress waves are rapidly attenuated in travelling through rock. As well, an earthquake may generate extremely high accelerations, but is limited in the maximum amount of stress that it can create. The question, however, of the actual specific nature of underground seismic motions still remains essentially unanswered, although it is expected that there is a reduction in peak motions with depth due to the effect of the free surface of the earth

  4. How Condom Discontinuation Occurs: Interviews With Emerging Adult Women.

    Science.gov (United States)

    Mullinax, Margo; Sanders, Stephanie; Dennis, Barbara; Higgins, Jenny; Fortenberry, J Dennis; Reece, Michael

    We have almost no data on how and when couples stop using condoms. This qualitative study investigated the process of condom discontinuation. From November 2013 to April 2014, a total of 25 women living in a college town in the Midwest, ages 18 to 25, participated in semistructured interviews centered around three domains: partner interactions, contraceptive use, and sexually transmitted infection (STI) prevention. Analysis followed a critical qualitative research orientation. Participants described actively seeking the best options to prevent pregnancy, perceiving condom discontinuation in favor of hormonal methods as a smart decision, and reported wanting to discontinue using condoms due to physical discomfort. Oftentimes, nonverbal communication around contextual instances of condom unavailability paved the way for discontinuation. Participants indicated the decision to stop using condoms was neither deliberate nor planned. Condom discontinuation rarely occurred at one point in time; instead, it was preceded by a period of occasional use. Even after participants described themselves as not using condoms, sporadic condom use was normal (typically related to fertility cycles). This study provides a more detailed understanding of how and why emerging adults negotiate condom discontinuation, thereby enhancing our ability to design effective condom continuation messages. Attention should be paid to helping emerging adults think more concretely about condom discontinuation.

  5. Adaptive Finite Element Methods for Elliptic Problems with Discontinuous Coefficients

    KAUST Repository

    Bonito, Andrea

    2013-01-01

    Elliptic PDEs with discontinuous diffusion coefficients occur in application domains such as diffusions through porous media, electromagnetic field propagation on heterogeneous media, and diffusion processes on rough surfaces. The standard approach to numerically treating such problems using finite element methods is to assume that the discontinuities lie on the boundaries of the cells in the initial triangulation. However, this does not match applications where discontinuities occur on curves, surfaces, or manifolds, and could even be unknown beforehand. One of the obstacles to treating such discontinuity problems is that the usual perturbation theory for elliptic PDEs assumes bounds for the distortion of the coefficients in the L∞ norm and this in turn requires that the discontinuities are matched exactly when the coefficients are approximated. We present a new approach based on distortion of the coefficients in an Lq norm with q < ∞ which therefore does not require the exact matching of the discontinuities. We then use this new distortion theory to formulate new adaptive finite element methods (AFEMs) for such discontinuity problems. We show that such AFEMs are optimal in the sense of distortion versus number of computations, and report insightful numerical results supporting our analysis. © 2013 Societ y for Industrial and Applied Mathematics.

  6. Predictors of premature discontinuation of treatment in multiple disease states

    Directory of Open Access Journals (Sweden)

    Eric Nantz

    2009-01-01

    Full Text Available Eric Nantz1, Hong Liu-Seifert2, Vladimir Skljarevski21Department of Statistics, Western Michigan University, Kalamazoo, MI, USA; 2Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USABackground: Premature discontinuation of treatment impacts outcomes of clinical practice. The traditional perception has been patient discontinuation is mainly driven by unwanted side effects. Systematic analysis of data from clinical trials across several disease states was performed to identify predictors of premature discontinuation during clinical interventions.Methods: A post hoc analysis was conducted on 22 randomized, double-blind, placebo-controlled clinical trials for treatment of fibromyalgia, diabetic peripheral neuropathic pain, major depressive disorder, and generalized anxiety disorder. Analyses were conducted on pooled data within each disease state.Results: Lack of early therapeutic response was a significant predictor of patient discontinuation in each disease state. Visit-wise changes in therapeutic response and severity of adverse events were also significant risk factors, with change in therapeutic response having a higher significance level in three disease states. Patients who discontinued due to adverse events had similar therapeutic responses as patients completing treatment.Conclusion: Contrary to the conventional belief that premature treatment discontinuation is primarily related to adverse events, our findings suggest lack of therapeutic response also plays a significant role in patient attrition. This research highlights the importance of systematic monitoring of therapeutic response in clinical practice as a measure to prevent patients’ discontinuation from pharmacological treatments.Keywords: attrition, depression, generalized anxiety disorder, fibromyalgia, therapeutic response, adverse event

  7. Natural language processing systems for capturing and standardizing unstructured clinical information: A systematic review.

    Science.gov (United States)

    Kreimeyer, Kory; Foster, Matthew; Pandey, Abhishek; Arya, Nina; Halford, Gwendolyn; Jones, Sandra F; Forshee, Richard; Walderhaug, Mark; Botsis, Taxiarchis

    2017-09-01

    We followed a systematic approach based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to identify existing clinical natural language processing (NLP) systems that generate structured information from unstructured free text. Seven literature databases were searched with a query combining the concepts of natural language processing and structured data capture. Two reviewers screened all records for relevance during two screening phases, and information about clinical NLP systems was collected from the final set of papers. A total of 7149 records (after removing duplicates) were retrieved and screened, and 86 were determined to fit the review criteria. These papers contained information about 71 different clinical NLP systems, which were then analyzed. The NLP systems address a wide variety of important clinical and research tasks. Certain tasks are well addressed by the existing systems, while others remain as open challenges that only a small number of systems attempt, such as extraction of temporal information or normalization of concepts to standard terminologies. This review has identified many NLP systems capable of processing clinical free text and generating structured output, and the information collected and evaluated here will be important for prioritizing development of new approaches for clinical NLP. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Identification of manganese as a toxicant in a groundwater treatment system: Addressing naturally occurring toxicants

    International Nuclear Information System (INIS)

    Goodfellow, W. Jr.; Sohn, V.; Richey, M.; Yost, J.

    1995-01-01

    Effluent from a groundwater remediation system at a bulk oil storage and distribution terminal has been chronically toxic to Ceriodaphnia dubia. The remediation system was designed in response to a hydrocarbon plume in the area of the terminal. The remediation system consists of a series of groundwater recovery wells and groundwater intercept trench systems with groundwater treatment and phased-separated hydrocarbon recovery systems. The groundwater treatment and petroleum recovery systems consist of oil/water separators, product recovery tanks, air strippers, filters, and carbon adsorption units. The characteristics of this effluent are low total suspended solids, total dissolved solids, and hardness concentrations as well as meeting stringent NPDES permit requirements for lead, copper, zinc, mercury, total petroleum hydrocarbons, and BTEX. Additional priority pollutant evaluations revealed no compounds of concern. Performance of a Toxicity identification Evaluation (TIE) indicated that manganese was the principle toxicant in the effluent. Manganese is a naturally occurring constituent in this groundwater source and is not added to the treatment system. This paper will present the results of the TIE with a discussion of treatability/control options for manganese control at this facility. Recommendations for addressing naturally occurring toxicants that are not a result of the facility's operations will also be presented

  9. Chemistry and migration behaviour of the actinides and fission products in natural aquatic systems

    International Nuclear Information System (INIS)

    Kim, J.I.; Warnecke, E.

    1986-10-01

    The 66th PTB seminar was held on April 24th and 25th, 1986, at the Munich Technical University (TUM) in Garching in cooperation with the Institute for Radiochemistry of the Munich Technical University, the 'Nuclear Chemistry' special group of the Society of German Chemists, and UB/SN responsible for the BMFT project. The seminar was organized by the TUM's Institute for Radiochemistry. The seminar dealt with the following main topics: primary geochemical reactions and colloid formation; sorption mechamisms and migration behaviour in Konrad/Gorleben aquifer systems; sampling and experimental investigations; evaluation and interpretation of the data obtained by experiments. The seminar was to achieve the following objectives: information and exchange of experience with regard to the work carried out up to the present; if necessary, formulation of new issues to be discussed; improvement of the interdisciplinary cooperation (chemistry, geosciences, modelling). The following topics and individual aspects were of particular interest and were given special attention: complementary basic research in order to interpret, support and model the results obtained by experiments (sorption mechanisms and thermodynamic data for natural systems); comparability of batch, column and diffusion tests; transferability of laboratory data to natural systems (e.g. Gorleben, Konrad); redox transitions for Np, Tc at Eh values of the natural systems; dependence of the sorption/desorption data on different influencing factors, importance of the influencing factors and selection of data for model calculations. Subject analyses of the individual contributions have been made for the Energy data base. (orig./RB) [de

  10. Ecological impacts of Synthetic Natural Gas from wood (SNG) used in current heating and car systems

    Energy Technology Data Exchange (ETDEWEB)

    Felder, R.; Dones, R.

    2007-07-01

    This illustrated poster illustrates how synthetic natural gas (SNG) from wood is a promising option to partially substitute fossil energy carriers. The comprehensive life cycle-based ecological impact of SNG is compared with that of natural gas, fuel oil, petrol/diesel, and wood chips that deliver the same services. The methods used for comparison, including Eco-indicator '99 perspectives, Eco-scarcity '97 (UBP), IPCC (2001), and external costs are discussed. The results indicate best ecological performance of the SNG system if consumption of fossil resources is strongly weighted. The performance of natural gas and wood-based systems are also discussed. The main negative aspects of the SNG system are discussed, as is the better ecological score of wood when highly-efficient particulate matter filters are installed. SNG is quoted as performing better than oil derivatives. External costs for SNG are examined. The authors recommend that SNG should preferably be used in cars, since the reduction of overall ecological impact and external costs when substituting oil-based fuels is higher for cars than for heating systems.

  11. A review of natural aerosol interactions and feedbacks within the Earth system

    Directory of Open Access Journals (Sweden)

    K. S. Carslaw

    2010-02-01

    Full Text Available The natural environment is a major source of atmospheric aerosols, including dust, secondary organic material from terrestrial biogenic emissions, carbonaceous particles from wildfires, and sulphate from marine phytoplankton dimethyl sulphide emissions. These aerosols also have a significant effect on many components of the Earth system such as the atmospheric radiative balance and photosynthetically available radiation entering the biosphere, the supply of nutrients to the ocean, and the albedo of snow and ice. The physical and biological systems that produce these aerosols can be highly susceptible to modification due to climate change so there is the potential for important climate feedbacks. We review the impact of these natural systems on atmospheric aerosol based on observations and models, including the potential for long term changes in emissions and the feedbacks on climate. The number of drivers of change is very large and the various systems are strongly coupled. There have therefore been very few studies that integrate the various effects to estimate climate feedback factors. Nevertheless, available observations and model studies suggest that the regional radiative perturbations are potentially several Watts per square metre due to changes in these natural aerosol emissions in a future climate. Taking into account only the direct radiative effect of changes in the atmospheric burden of natural aerosols, and neglecting potentially large effects on other parts of the Earth system, a global mean radiative perturbation approaching 1 W m−2 is possible by the end of the century. The level of scientific understanding of the climate drivers, interactions and impacts is very low.

  12. Understanding the systemic nature of cities to improve health and climate change mitigation.

    Science.gov (United States)

    Chapman, Ralph; Howden-Chapman, Philippa; Capon, Anthony

    2016-09-01

    Understanding cities comprehensively as systems is a costly challenge and is typically not feasible for policy makers. Nevertheless, focusing on some key systemic characteristics of cities can give useful insights for policy to advance health and well-being outcomes. Moreover, if we take a coevolutionary systems view of cities, some conventional assumptions about the nature of urban development (e.g. the growth in private vehicle use with income) may not stand up. We illustrate this by examining the coevolution of urban transport and land use systems, and institutional change, giving examples of policy implications. At a high level, our concern derives from the need to better understand the dynamics of urban change, and its implications for health and well-being. At a practical level, we see opportunities to use stylised findings about urban systems to underpin policy experiments. While it is now not uncommon to view cities as systems, policy makers appear to have made little use so far of a systems approach to inform choice of policies with consequences for health and well-being. System insights can be applied to intelligently anticipate change - for example, as cities are subjected to increasing natural system reactions to climate change, they must find ways to mitigate and adapt to it. Secondly, systems insights around policy cobenefits are vital for better informing horizontal policy integration. Lastly, an implication of system complexity is that rather than seeking detailed, 'full' knowledge about urban issues and policies, cities would be well advised to engage in policy experimentation to address increasingly urgent health and climate change issues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Discontinuous Spectral Difference Method for Conservation Laws on Unstructured Grids

    Science.gov (United States)

    Liu, Yen; Vinokur, Marcel; Wang, Z. J.

    2004-01-01

    A new, high-order, conservative, and efficient method for conservation laws on unstructured grids is developed. The concept of discontinuous and high-order local representations to achieve conservation and high accuracy is utilized in a manner similar to the Discontinuous Galerkin (DG) and the Spectral Volume (SV) methods, but while these methods are based on the integrated forms of the equations, the new method is based on the differential form to attain a simpler formulation and higher efficiency. A discussion on the Discontinuous Spectral Difference (SD) Method, locations of the unknowns and flux points and numerical results are also presented.

  14. Discontinuity of maximum entropy inference and quantum phase transitions

    International Nuclear Information System (INIS)

    Chen, Jianxin; Ji, Zhengfeng; Yu, Nengkun; Zeng, Bei; Li, Chi-Kwong; Poon, Yiu-Tung; Shen, Yi; Zhou, Duanlu

    2015-01-01

    In this paper, we discuss the connection between two genuinely quantum phenomena—the discontinuity of quantum maximum entropy inference and quantum phase transitions at zero temperature. It is shown that the discontinuity of the maximum entropy inference of local observable measurements signals the non-local type of transitions, where local density matrices of the ground state change smoothly at the transition point. We then propose to use the quantum conditional mutual information of the ground state as an indicator to detect the discontinuity and the non-local type of quantum phase transitions in the thermodynamic limit. (paper)

  15. Stacking by electroinjection with discontinuous buffers in capillary zone electrophoresis.

    Science.gov (United States)

    Shihabi, Zak K

    2002-08-01

    The work presented here demonstrates that electroinjection can be performed using discontinuous buffers, which can result in better stacking than that obtained by hydrodynamic injection. The sample can be concentrated at the tip of the capillary leaving practically the whole capillary for sample separation. This results in several advantages, such as better sample concentration, higher plate number and shorter time of stacking. However, sample introduction by electromigration is suited for samples free or low in salt content. Samples, which are high in salt content, are better introduced by the hydrodynamic injection for stacking by the discontinuous buffers. Different simple methods to introduce the discontinuity in the buffer for electroinjection are discussed.

  16. A Simple Stochastic Differential Equation with Discontinuous Drift

    DEFF Research Database (Denmark)

    Simonsen, Maria; Leth, John-Josef; Schiøler, Henrik

    2013-01-01

    In this paper we study solutions to stochastic differential equations (SDEs) with discontinuous drift. We apply two approaches: The Euler-Maruyama method and the Fokker-Planck equation and show that a candidate density function based on the Euler-Maruyama method approximates a candidate density...... function based on the stationary Fokker-Planck equation. Furthermore, we introduce a smooth function which approximates the discontinuous drift and apply the Euler-Maruyama method and the Fokker-Planck equation with this input. The point of departure for this work is a particular SDE with discontinuous...

  17. Risk of discontinuation of Advanced Therapy Medicinal Products clinical trials.

    Science.gov (United States)

    Hanna, Eve; Rémuzat, Cecile; Auquier, Pascal; Toumi, Mondher

    2016-01-01

    Advanced therapy medicinal products (ATMPs) constitute a class of innovative products that encompasses gene therapy, somatic cell therapy, and tissue-engineered products (TEP). There is an increased investment of commercial and non-commercial sponsors in this field and a growing number of ATMPs randomized clinical trials (RCT) and patients enrolled in such trials. RCT generate data to prove the efficacy of a new therapy, but the discontinuation of RCTs wastes scarce resources. Our objective is to identify the number and characteristics of discontinued ATMPs trials in order to evaluate the rate of discontinuation. We searched for ATMPs trials conducted between 1999 to June 2015 using three databases, which are Clinicaltrials.gov, the International Clinical Trials Registry Platform (ICTRP), and the EU Drug Regulating Authorities Clinical Trials (EudraCT). We selected the ATMPs trials after elimination of the duplicates. We identified the disease areas and the sponsors as commercial or non-commercial organizations. We classified ATMPs by type and trial status, that is, ongoing, completed, terminated, discontinued, and prematurely ended. Then, we calculated the rate of discontinuation. Between 1999 and June 2015, 143 withdrawn, terminated, or prematurely ended ATMPs clinical trials were identified. Between 1999 and June 2013, 474 ongoing and completed clinical trials were identified. Therefore, the rate of discontinuation of ATMPs trials is 23.18%, similar to that for non-ATMPs drugs in development. The probability of discontinuation is, respectively, 27.35, 16.28, and 16.34% for cell therapies, gene therapies, and TEP. The highest discontinuation rate is for oncology (43%), followed by cardiology (19.2%). It is almost the same for commercial and non-commercial sponsors; therefore, the discontinuation reason may not be financially driven. No failure risk rate per development phase is available for ATMPs. The discontinuation rate may prove helpful when assessing the

  18. Numerical Study on Radiation Effects to Evaporator in Natural Vacuum Solar Desalination System

    Science.gov (United States)

    Siregar, R. E. T.; Ronowikarto, A. D.; Setyawan, E. Y.; Ambarita, H.

    2018-01-01

    The need for clean water is increasing day by day due to the increasing factor of living standard of mankind, hence designed natural vacuum solar desalination. The natural vacuum Solar desalination is studied experimentally. A small-scale natural vacuum desalination study consists of evaporator and condenser as the main components designed and manufactured. To transfer heat from the solar collector into the evaporator, the fluid transfer system uses a pump powered by a solar cell. Thus, solar collectors are called hybrid solar collectors. The main purpose of this exposure is to know the characteristics of the radiation effects on incoming energy on the evaporator during the process. This system is tested by exposing the unit to the solar radiation in the 4th floor building in Medan. The experiment was conducted from 8.00 to 16.00 local time. The results show that natural vacuum solar desalination with hybrid solar collectors can be operated perfectly. If the received radiation is high, then the incoming energy received by the evaporator will also be high. From measurements with HOBO microstation, obtained the highest radiation 695.6 W/m2, and the calculation result of incoming energy received evaporator obtained highest result 1807.293 W.

  19. Dynamic Optimal Energy Flow in the Integrated Natural Gas and Electrical Power Systems

    DEFF Research Database (Denmark)

    Fang, Jiakun; Zeng, Qing; Ai, Xiaomeng

    2018-01-01

    . Simulation on the test case illustrates the success of the modelling and the beneficial roles of the power-to-gas are analyzed. The proposed model can be used in the decision support for both planning and operation of the coordinated natural gas and electrical power systems.......This work focuses on the optimal operation of the integrated gas and electrical power system with bi-directional energy conversion. Considering the different response times of the gas and power systems, the transient gas flow and steady- state power flow are combined to formulate the dynamic...... optimal energy flow in the integrated gas and power systems. With proper assumptions and simplifications, the problem is transformed into a single stage linear programming. And only a single stage linear programming is needed to obtain the optimal operation strategy for both gas and power systems...

  20. Origin of discontinuities in coal-bearing strata at roaring creek (basal Pennsylvanian of Indiana)

    Science.gov (United States)

    Nelson, W.J.; Eggert, D.L.; DiMichele, W.A.; Stecyk, A.C.

    1985-01-01

    Basal Pennsylvanian coal-bearing strata exposed along Roaring Creek, west-central Indiana, exhibit extreme lateral discontinuity. Coal seams abruptly change in thickness and elevation; they split, grade into shale, are cut out by channels and disrupted by soft-sediment deformational structures. Initial sediments were laid down by a network of southwest-flowing streams that traversed a deeply channelized upland surface of Mississippian carbonate rocks. Channels aggraded rapidly as uplands were worn down, so the region changed through time from uplands to upper deltaic plain. Local environments included channels, localized point bars, small natural levees and crevasse splays, overbank deposits, and swamps. Differential compaction and subsidence, slumping stream banks, and possibly collapsing sinkholes influenced sedimentation. As a consequence, coals are too discontinuous for economical mining, although they are locally thick and high in quality. ?? 1985.

  1. The Decision of Dismissal, Suspension, or Discontinuation of Employment of Public/Private School Teachers

    Directory of Open Access Journals (Sweden)

    Jui-Che Wu

    2014-06-01

    Full Text Available There have been controversies over the legal attribute of the decision of dismissal, suspension, or discontinuation of employment of public and private school teachers. The Supreme Administrative Court passed a resolution in July, 2009. In this resolution, the legal relationship between public schools and their teachers was regarded as administrative contracts while the legal attribute of the decision of dismissal, suspension, or discontinuation of employment was categorized into administrative dispositions. Besides, the administrative disposition will not take effect until it obtains approval from the competent educational authorities, and teachers can seek administrative appeal as remedy first, which makes remedy procedure complicated. Therefore, this study first attempts to categorize the legal relationship between the public and private schools and their teachers. Then, the legal attribute of the decision of dismissal, suspension, or discontinuation of employment and the remedy procedure are discussed. It is concluded in this study that the legal relationships between public/private schools and their teachers fall into the categories of administrative/civic contract respectively. Any decision of dismissal, suspension, or discontinuation of employment should be based on this categorization, and the remedy procedure can thus be reduced. Besides teacher’s appeal and re-appeal system being in accordance with Teacher’s Act, the appeal of declaratory judgment on contractual relationship to either the Administrative Court or the Civic Court can also be filed. As a result, the remedy procedure can be simplified to an extent to follow the basic principles stated in the resolution.

  2. Periodic synchronization control of discontinuous delayed networks by using extended Filippov-framework.

    Science.gov (United States)

    Cai, Zuowei; Huang, Lihong; Guo, Zhenyuan; Zhang, Lingling; Wan, Xuting

    2015-08-01

    This paper is concerned with the periodic synchronization problem for a general class of delayed neural networks (DNNs) with discontinuous neuron activation. One of the purposes is to analyze the problem of periodic orbits. To do so, we introduce new tools including inequality techniques and Kakutani's fixed point theorem of set-valued maps to derive the existence of periodic solution. Another purpose is to design a switching state-feedback control for realizing global exponential synchronization of the drive-response network system with periodic coefficients. Unlike the previous works on periodic synchronization of neural network, both the neuron activations and controllers in this paper are allowed to be discontinuous. Moreover, owing to the occurrence of delays in neuron signal, the neural network model is described by the functional differential equation. So we introduce extended Filippov-framework to deal with the basic issues of solutions for discontinuous DNNs. Finally, two examples and simulation experiments are given to illustrate the proposed method and main results which have an important instructional significance in the design of periodic synchronized DNNs circuits involving discontinuous or switching factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. The problem of the legal nature of Green Certificates in the Italian legal system

    International Nuclear Information System (INIS)

    Colcelli, Valentina

    2012-01-01

    Green Certificates are usually described as negotiable instruments or commercial papers. The Italian legal system identifies Green Certificates as rights but, due to the ambiguity of the definition, their juridical nature remains uncertain. This reverberates on the functioning of the Green Certificates market and on the enforcement of the relevant norms. This paper discusses the actual legal nature of Green Certificates in Italy and concludes that they should be regarded as goods. This means that private law instruments apply in their market transactions, with consequent implications on the policy side. - Highlights: ► A definition of Green Certificates in the Italian legal system is provided. ► Green Certificates are not Credit Instruments. ► However, they may be negotiated separately from the energy they represent. ► Green Certificates are goods, which relate to new properties.

  4. Implementation of a Geographical Information System. GIS, in the Natural National Park, Cliffs of Cali

    International Nuclear Information System (INIS)

    Zapata Pardo, Maria Victoria; Martinez Zarate, Camilo; Gonzalez, Carlos A

    1999-01-01

    The objective of this project was to generate a tool to improve the handling, conservation and administration of the Park National Natural - Cliffs of Cali, belonging to the Special Administrative Unit of the System of Natural National Parks, UAESPNN, of the Ministry of the Environment. With this purpose it was implemented a System of Geographical Information, GIS, like methodological model. The GIS; Cliffs of Cali used a database relational, developed with the software ACCESS t m, compatible with the used GIS Arc/INFO t m and Arc/View t m (for work station). The data space accessed to the database were those of topography, hydrology, areas of life, geology, limit, fronts, to zone with handling ends, precipitation, indigenous occupation and municipalities; it contain related alphanumeric information, administrative, socioeconomic handling and physique among others

  5. Design of intelligent systems based on fuzzy logic, neural networks and nature-inspired optimization

    CERN Document Server

    Castillo, Oscar; Kacprzyk, Janusz

    2015-01-01

    This book presents recent advances on the design of intelligent systems based on fuzzy logic, neural networks and nature-inspired optimization and their application in areas such as, intelligent control and robotics, pattern recognition, time series prediction and optimization of complex problems. The book is organized in eight main parts, which contain a group of papers around a similar subject. The first part consists of papers with the main theme of theoretical aspects of fuzzy logic, which basically consists of papers that propose new concepts and algorithms based on fuzzy systems. The second part contains papers with the main theme of neural networks theory, which are basically papers dealing with new concepts and algorithms in neural networks. The third part contains papers describing applications of neural networks in diverse areas, such as time series prediction and pattern recognition. The fourth part contains papers describing new nature-inspired optimization algorithms. The fifth part presents div...

  6. Review article: the use of remotely piloted aircraft systems (RPASs) for natural hazards monitoring and management

    Science.gov (United States)

    Giordan, Daniele; Hayakawa, Yuichi; Nex, Francesco; Remondino, Fabio; Tarolli, Paolo

    2018-04-01

    The number of scientific studies that consider possible applications of remotely piloted aircraft systems (RPASs) for the management of natural hazards effects and the identification of occurred damages strongly increased in the last decade. Nowadays, in the scientific community, the use of these systems is not a novelty, but a deeper analysis of the literature shows a lack of codified complex methodologies that can be used not only for scientific experiments but also for normal codified emergency operations. RPASs can acquire on-demand ultra-high-resolution images that can be used for the identification of active processes such as landslides or volcanic activities but can also define the effects of earthquakes, wildfires and floods. In this paper, we present a review of published literature that describes experimental methodologies developed for the study and monitoring of natural hazards.

  7. Explicit formulation for natural frequencies of double-beam system with arbitrary boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mirzabeigy, Alborz; Madoliat, Reza [Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Dabbagh, Vahid [University of Malaya, Kuala Lumpur (Malaysia)

    2017-02-15

    In this paper, free transverse vibration of two parallel beams connected through Winkler type elastic layer is investigated. Euler- Bernoulli beam hypothesis has been applied and it is assumed that boundary conditions of upper and lower beams are similar while arbitrary without any limitation even for non-ideal boundary conditions. Material properties and cross-section geometry of beams could be different from each other. The motion of the system is described by a homogeneous set of two partial differential equations, which is solved by using the classical Bernoulli-Fourier method. Explicit expressions are derived for the natural frequencies. In order to verify accuracy of results, the problem once again solved using modified Adomian decomposition method. Comparison between results indicates excellent accuracy of proposed formulation for any arbitrary boundary conditions. Derived explicit formulation is simplest method to determine natural frequencies of double-beam systems with high level of accuracy in comparison with other methods in literature.

  8. Early warning, warning or alarm systems for natural hazards? A generic classification.

    Science.gov (United States)

    Sättele, Martina; Bründl, Michael; Straub, Daniel

    2013-04-01

    Early warning, warning and alarm systems have gained popularity in recent years as cost-efficient measures for dangerous natural hazard processes such as floods, storms, rock and snow avalanches, debris flows, rock and ice falls, landslides, flash floods, glacier lake outburst floods, forest fires and even earthquakes. These systems can generate information before an event causes loss of property and life. In this way, they mainly mitigate the overall risk by reducing the presence probability of endangered objects. These systems are typically prototypes tailored to specific project needs. Despite their importance there is no recognised system classification. This contribution classifies warning and alarm systems into three classes: i) threshold systems, ii) expert systems and iii) model-based expert systems. The result is a generic classification, which takes the characteristics of the natural hazard process itself and the related monitoring possibilities into account. The choice of the monitoring parameters directly determines the system's lead time. The classification of 52 active systems moreover revealed typical system characteristics for each system class. i) Threshold systems monitor dynamic process parameters of ongoing events (e.g. water level of a debris flow) and incorporate minor lead times. They have a local geographical coverage and a predefined threshold determines if an alarm is automatically activated to warn endangered objects, authorities and system operators. ii) Expert systems monitor direct changes in the variable disposition (e.g crack opening before a rock avalanche) or trigger events (e.g. heavy rain) at a local scale before the main event starts and thus offer extended lead times. The final alarm decision incorporates human, model and organisational related factors. iii) Model-based expert systems monitor indirect changes in the variable disposition (e.g. snow temperature, height or solar radiation that influence the occurrence probability

  9. Discontinuation of continuous renal replacement therapy: A post hoc analysis of a prospective multicenter observational study

    NARCIS (Netherlands)

    Uchino, Shigehiko; Bellomo, Rinaldo; Morimatsu, Hiroshi; Morgera, Stanislao; Schetz, Miet; Tan, Ian; Bouman, Catherine; Macedo, Ettiene; Gibney, Noel; Tolwani, Ashita; Oudemans-van Straaten, Heleen; Ronco, Claudio; Kellum, John A.

    2009-01-01

    Objectives: To describe current practice for the discontinuation of continuous renal replacement therapy in a multinational setting and to identify variables associated with successful discontinuation. The approach to discontinue continuous renal replacement therapy may affect patient outcomes.

  10. Evaluation of CO2-precooled Nitrogen Expander Systems for Natural Gas Liquefaction

    OpenAIRE

    Hasle, Siv Avdal

    2013-01-01

    This Master thesis is a continuation of a project thesis written fall 2012 ?Evaluation of Liquefaction systems for Floating LNG?. Two processes for liquefaction of natural gas for a floating unit was compared and evaluated. The main basis for comparison came from simulations conducted in the simulation program Aspen HYSYS. These two processes were a dual mixed refrigerant process, DMR, from Air Products and Chemicals and a turbo-expander process from TOTAL. (Ref) The specific power consumpti...

  11. Numerical analysis of a natural convection cooling system for radioactive canisters storage

    Energy Technology Data Exchange (ETDEWEB)

    Tsal, R.J.; Anwar, S.; Mercada, M.G. [Fluor Daniel Inc., Irvine, CA (United States)

    1995-02-01

    This paper describes the use of numerical analysis for studying natural convection cooling systems for long term storage of heat producing radioactive materials, including special nuclear materials and nuclear waste. The paper explains the major design philosophy, and shares the experiences of numerical modeling. The strategy of storing radioactive material is to immobilize nuclear high-level waste by a vitrification process, convertion it into borosilicate glass, and cast the glass into stainless steel canisters. These canisters are seal welded, decontaminated, inspected, and temporarily stored in an underground vault until they can be sent to a geologic repository for permanent storage. These canisters generate heat by nuclear decay of radioactive isotopes. The function of the storage facility ventilation system is to ensure that the glass centerline temperature does not exceed the glass transition temperature during storage and the vault concrete temperatures remain within the specified limits. A natural convection cooling system was proposed to meet these functions. The effectiveness of a natural convection cooling system is dependent on two major factors that affect air movement through the vault for cooling the canisters: (1) thermal buoyancy forces inside the vault which create a stack effect, and (2) external wind forces, that may assist or oppose airflow through the vault. Several numerical computer models were developed to analyze the thermal and hydraulic regimes in the storage vault. The Site Model is used to simulate the airflow around the building and to analyze different air inlet/outlet devices. The Airflow Model simulates the natural convection, thermal regime, and hydraulic resistance in the vault. The Vault Model, internal vault temperature stratification; and, finally, the Hot Area Model is used for modeling concrete temperatures within the vault.

  12. Bistability of the naturally induced lactose utilization system of Escherichia coli

    Science.gov (United States)

    Stajic, Jelena; Wall, Michael

    2006-03-01

    In the absence of the preferred sugar glucose, lactose utilization machinery in the bacterium E. coli is activated. The genetic circuit responsible for this response, lac operon, has been observed to exhibit bistability when induced by an artificial inducer, TMG. Here we investigate conditions under which bistability might be observed in response to lactose. The aim of our study is to establish whether the natural system exhibits bistability, as is often assumed despite the lack of experimental support.

  13. Fluvial obstacle marks as complex geomorphic systems: a comparison between physically modelled and natural forms

    Science.gov (United States)

    Euler, T.

    2009-04-01

    Fluvial obstacle marks are bedforms that develop if flow is separated by an immobile obstacle at the stream bed. Due to local acceleration and deceleration of the flow, areas of potential erosion and deposition arise in the obstacle surrounding. This results in forms that commonly consist of a scour hole reaching from the upstream part to the sides of an obstacle and an adjacent depositional ridge. Natural fluvial obstacle marks develop around pebbles, boulders, woody debris and plants. Individual forms of obstacle marks result from specific current patterns in the obstacle surrounding, which in turn are dependent on a variety of independent parameters like obstacle shape, -inclination, -alignment, -geometry, -porosity, -surface roughness and -flexibility as well as on sediment grading, bed-resistance, flow velocity, flow depth and steadiness of flow. Reciprocal interactions of these parameters make natural obstacle marks noteworthy examples of complex geomorphic systems. In contrast, experimentally simulated obstacle marks in laboratory flumes can be regarded as complexity-reduced geomorphic systems and are characterised by diverging morphological features compared to natural obstacle marks. In spite of these emergent divergences flume experiments are still inevitable to identify principle formative processes. Also experimental simulations are necessary to develop physically-based explanatory approaches that can predict significant morphometric features (like maximum depth of scour, eroded/deposited material) of fluvial obstacle marks. Within the scope of this work examples of natural fluvial obstacle marks are compared with obstacle marks simulated experimentally in a laboratory flume. In spite of morphological differences it can be deduced that a horseshoe-vortex system is the main agent that drives formative processes in the obstacle surrounding. The input of kinetic energy into this vortex system can be well described by determining the obstacle Reynolds

  14. Improvements in robotic natural orifice surgery with a novel material handling system.

    Science.gov (United States)

    Midday, Jeff; Nelson, Carl A; Oleynikov, Dmitry

    2013-09-01

    Natural orifice translumenal endoscopic surgery (NOTES) has many potential advantages over other minimally invasive surgical techniques, but it presents a number of challenges introduced by the restrictive natural access points. Fully insertable dexterous in vivo robots have been developed that eliminate the spatial restrictions of the entry point, but they also are isolated within the abdomen. A material handling system (MHS) developed to bridge the gap between the in vivo robots and the surgical team promises a number of improvements over other current technologies. The MHS was implemented with two different nonsurvival swine models to validate the utility and benefits of the system. The first procedure was attempted transgastrically but proved too difficult because the geometry of the esophagus was prohibitively small. The system was instead inserted via a 50-mm GelPort and tested for robustness. The second procedure used a transvaginal insertion via a custom 25-mm trocar. Throughout both procedures, the practitioners were asked for qualitative feedback regarding the effectiveness of the device and its long-term efficiencies. The MHS was able to deliver a standard surgical staple securely to the peritoneal cavity. The practitioner was able to use the laparoscopic grasper both to insert and to remove the staple from the MHS. The system also proved capable of maintaining insufflation pressure throughout a procedure. It was cycled a total of five times in both the insertion and the retraction directions. Visualization from the MHS camera was poor at times because the lighting on the system was somewhat inadequate. No excessive bleeding or collateral damage to surrounding tissues was observed during the procedure. This study demonstrated that the MHS is fully capable of achieving payload transport during a NOTES operation. The system is intuitive and easy to use. It dramatically decreases collateral trauma in the natural access point and can advantageously reduce

  15. How nature designs light-harvesting antenna systems: design principles and functional realization in chlorophototrophic prokaryotes

    Science.gov (United States)

    Bryant, Donald A.; Canniffe, Daniel P.

    2018-02-01

    Chlorophyll-based phototrophs, or chlorophototrophs, convert light energy into stored chemical potential energy using two types of photochemical reaction center (RC), denoted type-1 and type-2. After excitation with light, a so-called special pair of chlorophylls in the RC is oxidized, and an acceptor is reduced. To ensure that RCs function at maximal rates in diffuse and variable light conditions, chlorophototrophs have independently evolved diverse light-harvesting antenna systems to rapidly and efficiently transfer that energy to the RCs. Energy transfer between weakly coupled chromophores is generally believed to proceed by resonance energy transfer, a dipole-induced-dipole process that was initially described theoretically by Förster. Nature principally optimizes three parameters in antenna systems: the distance separating the donor and acceptor chromophores, the relative orientations of those chromophores, and the spectral overlap between the donor and the acceptor chromophores. However, there are other important biological parameters that nature has optimized, and some common themes emerge from comparisons of different antenna systems. This tutorial considers structural and functional characteristics of three fundamentally different light-harvesting antenna systems of chlorophotrophic bacteria: phycobilisomes of cyanobacteria, the light-harvesting complexes (LH1 and LH2) of purple bacteria, and chlorosomes of green bacteria. Phycobilisomes are generally considered to represent an antenna system in which the chromophores are weakly coupled, while the strongly coupled bacteriochlorophyll molecules in LH1 and LH2 are strongly coupled and are better described by exciton theory. Chlorosomes can contain up to 250 000 bacteriochlorophyll molecules, which are very strongly coupled and form supramolecular, nanotubular arrays. The general and specific principles that have been optimized by natural selection during the evolution of these diverse light

  16. Atomic switch networks-nanoarchitectonic design of a complex system for natural computing.

    Science.gov (United States)

    Demis, E C; Aguilera, R; Sillin, H O; Scharnhorst, K; Sandouk, E J; Aono, M; Stieg, A Z; Gimzewski, J K

    2015-05-22

    Self-organized complex systems are ubiquitous in nature, and the structural complexity of these natural systems can be used as a model to design new classes of functional nanotechnology based on highly interconnected networks of interacting units. Conventional fabrication methods for electronic computing devices are subject to known scaling limits, confining the diversity of possible architectures. This work explores methods of fabricating a self-organized complex device known as an atomic switch network and discusses its potential utility in computing. Through a merger of top-down and bottom-up techniques guided by mathematical and nanoarchitectonic design principles, we have produced functional devices comprising nanoscale elements whose intrinsic nonlinear dynamics and memorization capabilities produce robust patterns of distributed activity and a capacity for nonlinear transformation of input signals when configured in the appropriate network architecture. Their operational characteristics represent a unique potential for hardware implementation of natural computation, specifically in the area of reservoir computing-a burgeoning field that investigates the computational aptitude of complex biologically inspired systems.

  17. Environment between System and Nature: Alan Sonfist and the Art of the Cybernetic Environment

    Directory of Open Access Journals (Sweden)

    Etienne Benson

    2014-09-01

    Full Text Available This paper examines the role of systems thinking in environmental(ist art and activism through a close reading and contextualization of Army Ants: Patterns and Structures (1972, an installation by Alan Sonfist, one of the leading figures in U.S. land art and environmental art of the 1960s and 1970s. It challenges a commonly held retrospective understanding of "environmental art" as being inherently about bringing nature into art (or into the gallery by showing how important systems thinking, which blurred the natural-cultural divide, was to Sonfist and other artists of the time. It suggests that these two understandings of the environment -- one focused on nature, the other on systems -- were both allied and in tension, and that the unexpected technical problems faced by Army Ants can be attributed at least in part to a failure to acknowledge those tensions. Similarly, the paper suggests, the legacy of glossing over these different understandings of the environment has been at the root of broader conceptual problems with environmental art and activism.

  18. Atomic switch networks—nanoarchitectonic design of a complex system for natural computing

    Science.gov (United States)

    Demis, E. C.; Aguilera, R.; Sillin, H. O.; Scharnhorst, K.; Sandouk, E. J.; Aono, M.; Stieg, A. Z.; Gimzewski, J. K.

    2015-05-01

    Self-organized complex systems are ubiquitous in nature, and the structural complexity of these natural systems can be used as a model to design new classes of functional nanotechnology based on highly interconnected networks of interacting units. Conventional fabrication methods for electronic computing devices are subject to known scaling limits, confining the diversity of possible architectures. This work explores methods of fabricating a self-organized complex device known as an atomic switch network and discusses its potential utility in computing. Through a merger of top-down and bottom-up techniques guided by mathematical and nanoarchitectonic design principles, we have produced functional devices comprising nanoscale elements whose intrinsic nonlinear dynamics and memorization capabilities produce robust patterns of distributed activity and a capacity for nonlinear transformation of input signals when configured in the appropriate network architecture. Their operational characteristics represent a unique potential for hardware implementation of natural computation, specifically in the area of reservoir computing—a burgeoning field that investigates the computational aptitude of complex biologically inspired systems.

  19. Climate change and geothermal ecosystems: natural laboratories, sentinel systems, and future refugia.

    Science.gov (United States)

    O'Gorman, Eoin J; Benstead, Jonathan P; Cross, Wyatt F; Friberg, Nikolai; Hood, James M; Johnson, Philip W; Sigurdsson, Bjarni D; Woodward, Guy

    2014-11-01

    Understanding and predicting how global warming affects the structure and functioning of natural ecosystems is a key challenge of the 21st century. Isolated laboratory and field experiments testing global change hypotheses have been criticized for being too small-scale and overly simplistic, whereas surveys are inferential and often confound temperature with other drivers. Research that utilizes natural thermal gradients offers a more promising approach and geothermal ecosystems in particular, which span a range of temperatures within a single biogeographic area, allow us to take the laboratory into nature rather than vice versa. By isolating temperature from other drivers, its ecological effects can be quantified without any loss of realism, and transient and equilibrial responses can be measured in the same system across scales that are not feasible using other empirical methods. Embedding manipulative experiments within geothermal gradients is an especially powerful approach, informing us to what extent small-scale experiments can predict the future behaviour of real ecosystems. Geothermal areas also act as sentinel systems by tracking responses of ecological networks to warming and helping to maintain ecosystem functioning in a changing landscape by providing sources of organisms that are preadapted to different climatic conditions. Here, we highlight the emerging use of geothermal systems in climate change research, identify novel research avenues, and assess their roles for catalysing our understanding of ecological and evolutionary responses to global warming. © 2014 John Wiley & Sons Ltd.

  20. Natural Medicines Used in the Traditional Tibetan Medical System for the Treatment of Liver Diseases

    Science.gov (United States)

    Li, Qi; Li, Hai-Jiao; Xu, Tong; Du, Huan; Huan Gang, Chen-Lei; Fan, Gang; Zhang, Yi

    2018-01-01

    Liver disease is one of the most risk factors threatening human health. It is of great significance to find drugs that can treat liver diseases, especially for acute and chronic hepatitis, non-alcoholic fatty liver disease, and liver cancer. The search for drugs with good efficacy from traditional natural medicines has attracted more and more attention. Tibetan medicine, one of the China's traditional medical systems, has been widely used by the Tibetan people for the prevention and treatment of liver diseases for hundreds of years. The present paper summarized the natural Tibetan medicines that have been used in Tibetan traditional system of medicine to treat liver diseases by bibliographic investigation of 22 Tibetan medicine monographs and drug standards. One hundred and ninety three species including 181 plants, 7 animals, and 5 minerals were found to treat liver diseases in traditional Tibetan medicine system. The most frequently used species are Carthamus tinctorius, Brag-zhun, Swertia chirayita, Swertia mussotii, Halenia elliptica, Herpetospermum pedunculosum, and Phyllanthus emblica. Their names, families, medicinal parts, traditional uses, phytochemicals information, and pharmacological activities were described in detail. These natural medicines might be a valuable gift from the old Tibetan medicine to the world, and would be potential drug candidates for the treatment of liver diseases. Further studies are needed to prove their medicinal values in liver diseases treatment, identify bioactive compounds, elucidate the underlying mechanism of action, and clarify their side effects or toxicity with the help of modern phytochemical, pharmacological, metabonomics, and/or clinical trial methods. PMID:29441019

  1. Variability of the Quorum Sensing System in Natural Isolates of Bacillus sp.

    Directory of Open Access Journals (Sweden)

    Ines Mandic-Mulec

    2003-01-01

    Full Text Available Bacteria communicate with one another by (emitting and/or reacting to chemical signals. These communications, also known as quorum sensing, enable cells to control gene expression in response to cell density at the intra- and inter-species level. While bacteria use common signaling themes, variations in the design of the extracellular signals, the signal detection apparatus, and the biochemical mechanisms of signal relay have allowed quorum sensing systems to be adapted to diverse uses. The quorum sensing systems that govern natural genetic competence in Bacillus subtilis involve the ComX pheromones and the ComP-ComA, two-component regulator. ComX is synthesized as an inactive precursor and is then cleaved and modified by ComQ before export to the extra-cellular environment. The comQXP' loci of a set of natural Bacillus isolates have been sequenced and a striking polymorphism that correlates with specific patterns of activation of the quorum sensing response was shown. The ComX molecules representing different pherotypes were purified and characterized by mass spectroscopy. The analyses revealed that ComX variants also differ at the level of posttranslational modification of a conserved tryptophane residue, which was found to be an isoprenoid. The striking variability found in competence quorum sensing systems might be important for the survival of these bacteria in nature to escape the inappropriate induction of competence by closely related strains, playing the role of a sexual isolation mechanism.

  2. Performance Recovery of Natural Draft Dry Cooling Systems by Combined Air Leading Strategies

    Directory of Open Access Journals (Sweden)

    Weijia Wang

    2017-12-01

    Full Text Available The cooling efficiency of natural draft dry cooling system (NDDCS are vulnerable to ambient winds, so the implementation of measures against the wind effects is of great importance. This work presents the combined air leading strategies to recover the flow and heat transfer performances of NDDCS. Following the energy balance among the exhaust steam, circulating water, and cooling air, numerical models of natural draft dry cooling systems with the combined air leading strategies are developed. The cooling air streamlines, volume effectiveness, thermal efficiency and outlet water temperature for each cooling delta of the large-scale heat exchanger are obtained. The overall volume effectiveness, average outlet water temperature of NDDCS and steam turbine back pressure are calculated. The results show that with the air leading strategies inside or outside the dry-cooling tower, the thermo-flow performances of natural draft dry cooling system are improved under all wind conditions. The combined inner and outer air leading strategies are superior to other single strategy in the performance recovery, thus can be recommended for NDDCS in power generating units.

  3. Natural Medicines Used in the Traditional Tibetan Medical System for the Treatment of Liver Diseases.

    Science.gov (United States)

    Li, Qi; Li, Hai-Jiao; Xu, Tong; Du, Huan; Huan Gang, Chen-Lei; Fan, Gang; Zhang, Yi

    2018-01-01

    Liver disease is one of the most risk factors threatening human health. It is of great significance to find drugs that can treat liver diseases, especially for acute and chronic hepatitis, non-alcoholic fatty liver disease, and liver cancer. The search for drugs with good efficacy from traditional natural medicines has attracted more and more attention. Tibetan medicine, one of the China's traditional medical systems, has been widely used by the Tibetan people for the prevention and treatment of liver diseases for hundreds of years. The present paper summarized the natural Tibetan medicines that have been used in Tibetan traditional system of medicine to treat liver diseases by bibliographic investigation of 22 Tibetan medicine monographs and drug standards. One hundred and ninety three species including 181 plants, 7 animals, and 5 minerals were found to treat liver diseases in traditional Tibetan medicine system. The most frequently used species are Carthamus tinctorius , Brag-zhun, Swertia chirayita, Swertia mussotii, Halenia elliptica, Herpetospermum pedunculosum , and Phyllanthus emblica . Their names, families, medicinal parts, traditional uses, phytochemicals information, and pharmacological activities were described in detail. These natural medicines might be a valuable gift from the old Tibetan medicine to the world, and would be potential drug candidates for the treatment of liver diseases. Further studies are needed to prove their medicinal values in liver diseases treatment, identify bioactive compounds, elucidate the underlying mechanism of action, and clarify their side effects or toxicity with the help of modern phytochemical, pharmacological, metabonomics, and/or clinical trial methods.

  4. Top 40 questions in coupled human and natural systems (CHANS research

    Directory of Open Access Journals (Sweden)

    Daniel Boyd. Kramer

    2017-06-01

    Full Text Available Understanding and managing coupled human and natural systems (CHANS is a central challenge of the 21st century, but more focus is needed to pursue the most important questions within this vast field given limited research capacity and funding. We present 40 important questions for CHANS research, identified through a two-part crowdsourcing exercise within the CHANS community. We solicited members of the International Network of Research on Coupled Human and Natural Systems (CHANS-Net to submit up to three questions that they considered transformative, receiving 540 questions from 207 respondents. After editing for clarity and consistency, we asked the network's members to each evaluate a random subset of 20 questions in importance on a scale from 1 (least important to 7 (extremely important. Questions on land use and agriculture topped the list, with a median importance ranking of 5.7, followed by questions of scale, climate change and energy, sustainability and development, adaptation and resilience, in addition to seven other categories. We identified 40 questions with a median importance of 6.0 or above, which we highlight as the current view of researchers active in the field as research questions to pursue in order to maximize impact on understanding and managing coupled human and natural systems for achieving sustainable development goals and addressing emerging global challenges.

  5. Gas management of measurement system; Sistema informatizado de programacao e controle integrado de gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Niedersberg, Luis Carlos [Companhia de Gas do Estado do Rio Grande do Sul (Sulgas), Porto Alegre, RS (Brazil). Coordenacao de Programacao e Controle Integrado; Gomes, Lea Visali [Companhia de Gas do Estado do Rio Grande do Sul (Sulgas), Porto Alegre, RS (Brazil). Gerencia Executiva de Logistica de Operacoes

    2008-07-01

    This paper has for objective to present the software developed for control of measurement of natural gas in the Gas Company of the Rio Grande do Sul State - Sulgas. This paper will be presented the previous control system, developed as Microsoft Excel and the new system developed in Company's ERP. This software automated great part of the process, reducing possible mistakes, reducing the reverse-work index and improving the quality of the measurements considerably and of the revenue of the Company. (author)

  6. Modelling discontinuous well log signal to identify lithological ...

    Indian Academy of Sciences (India)

    Identification of sharp and discontinuous lithological boundaries from well log signal stemming fromheterogeneous subsurface structures assumes a special significance in geo-exploration studies. Well logdata acquired from various geological settings generally display nonstationary/nonlinear characteristicswith varying ...

  7. Clopidogrel discontinuation after myocardial infarction and risk of thrombosis

    DEFF Research Database (Denmark)

    Charlot, Mette; Nielsen, Lars Hougaard; Lindhardsen, Jesper

    2012-01-01

    The benefit of extending clopidogrel treatment beyond the 12-month period recommended in current guidelines after myocardial infarction (MI) is debated. We analysed the risk of adverse cardiovascular outcomes after discontinuation of 12 months of clopidogrel treatment....

  8. Reasons for discontinuation of implanon among users in Buffalo City ...

    African Journals Online (AJOL)

    Reasons for discontinuation of implanon among users in Buffalo City Metropolitan Municipality, South Africa: a cross-sectional study. Khungelwa Patricia Mrwebi, Daniel Ter Goon, Eyitayo Omolara Owolabi, Oladele Vincent Adeniyi, Eunice Seekoe, Anthony Idowu Ajayi ...

  9. On cell entropy inequality for discontinuous Galerkin methods

    Science.gov (United States)

    Jiang, Guangshan; Shu, Chi-Wang

    1993-01-01

    We prove a cell entropy inequality for a class of high order discontinuous Galerkin finite element methods approximating conservation laws, which implies convergence for the one dimensional scalar convex case.

  10. Discontinuous conduction mode analysis of phase-modulated series ...

    Indian Academy of Sciences (India)

    modulated dc–dc series resonant converter (SRC) operating in discontinuous conduction mode (DCM). The conventional fundamental harmonic approximation technique is extended for a non-ideal series resonant tank to clarify the limitations of ...

  11. Rotational discontinuities and the structure of the magnetopause

    International Nuclear Information System (INIS)

    Swift, D.W.; Lee, L.C.

    1983-01-01

    Symmetric and asymmetric rotational discontinuities are studied by means of a one-dimensional computer simulation and by single-particle trajectory calculations. The numerical simulations show the symmetric rotation to be stable for both ion and electron senses of rotation with a thickness of the order of a few ion gyroradii when the rotation angle of the tangential field is 180 0 or less. Larger rotation angles tend to be unstable. In an expansive discontinuity, when the magnetic field on the downstream side of the discontinuity is larger, an expanding transition layer separating the high-field from a low-field region develops on the downstream side, and a symmetric rotational discontinuity forms at the upstream edge. The implication of these results for magnetopause structure and energy flow through the magnetopause is described

  12. On the Issue of Labor Relations Discontinuance by Staff Reduction

    Directory of Open Access Journals (Sweden)

    Sheveleva A. A.

    2012-11-01

    Full Text Available This article is devoted to consideration of issues related to the procedure of labor law contract termination by staff reduction. The author, analyzing the judicial practice, gives practical recommendations on the procedure of employment relationships discontinuance

  13. Father's Labour Migration and Children's School Discontinuation in Rural Mozambique.

    Science.gov (United States)

    Yabiku, Scott T; Agadjanian, Victor

    2017-08-01

    We examine how the discontinuation of schooling among left-behind children is related to multiple dimensions of male labor migration: the accumulation of migration experience, the timing of these migration experiences in the child's life course, and the economic success of the migration. Our setting is rural southern Mozambique, an impoverished area with massive male labor out-migration. Results show that fathers' economically successful labor migration is more beneficial for children's schooling than unsuccessful migration or non-migration. There are large differences, however, by gender: compared to sons of non-migrants, sons of migrant fathers (regardless of migration success) have lower rates of school discontinuation, while daughters of migrant fathers have rates of school discontinuation no different than daughters of non-migrants. Furthermore, accumulated labor migration across the child's life course is beneficial for boys' schooling, but not girls'. Remittances sent in the past year reduce the rate of discontinuation for sons, but not daughters.

  14. Testing an AAC system that transforms pictograms into natural language with persons with cerebral palsy.

    Science.gov (United States)

    Pahisa-Solé, Joan; Herrera-Joancomartí, Jordi

    2017-10-18

    In this article, we describe a compansion system that transforms the telegraphic language that comes from the use of pictogram-based augmentative and alternative communication (AAC) into natural language. The system was tested with four participants with severe cerebral palsy and ranging degrees of linguistic competence and intellectual disabilities. Participants had used pictogram-based AAC at least for the past 30 years each and presented a stable linguistic profile. During tests, which consisted of a total of 40 sessions, participants were able to learn new linguistic skills, such as the use of basic verb tenses, while using the compansion system, which proved a source of motivation. The system can be adapted to the linguistic competence of each person and required no learning curve during tests when none of its special features, like gender, number, verb tense, or sentence type modifiers, were used. Furthermore, qualitative and quantitative results showed a mean communication rate increase of 41.59%, compared to the same communication device without the compansion system, and an overall improvement in the communication experience when the output is in natural language. Tests were conducted in Catalan and Spanish.

  15. Flashing in riser and its effect on flow stability in natural circulation system

    International Nuclear Information System (INIS)

    Wu Xinxin; Wu Shaorong; Jiang Shengyao; Zhou Lei; Tong Yunxian; Zhang Youjie; Han Bing

    1991-09-01

    The experimental investigation was performed in the full scale thermo-hydraulic simulation test loop (HRTL-5) for the 5 MW-Heating Reactor at Institute of Nuclear Energy Technology, Tsinghua University. Under different pressures the flashing in riser of natural circulation system and its effect on flow stability were studied by the method of visual observation in synchronism with data recording. The results show that the lower the system pressure, the more obvious the flashing in the riser, and the stronger the effect on flow stability in the natural circulation system. Under very low pressure even if subcooling at the exit of heated test section is relatively higher, the flashing riser will appears due to gradual energy accumulation by strong thermodynamic non-equilibrium process. Consequently, a long period flow oscillation is stimulated in the system, and the time of period can be up to 40 s. When the system pressure reaches to 1.5 MPa, the flashing in riser is vanished. Based on these experiments, the mechanism of flashing in riser and the flow instability stimulated by the flashing are basically explained

  16. Oral anticoagulant discontinuation in patients with nonvalvular atrial fibrillation.

    Science.gov (United States)

    Kachroo, Sumesh; Hamilton, Melissa; Liu, Xianchen; Pan, Xianying; Brixner, Diana; Marrouche, Nassir; Biskupiak, Joseph

    2016-01-01

    To identify factors associated with all-cause discontinuation (patient discontinued on their own or physician discontinuation) of oral anticoagulants (OACs) among nonvalvular atrial fibrillation (NVAF) patients. Retrospective cohort study. We analyzed the MarketScan claims database from October 2009 to July 2012. Adult patients were eligible if they newly initiated an OAC in the study period, had an atrial fibrillation diagnosis (International Classification of Diseases, Ninth Revision, Clinical Modification code 427.31 or 472.32), and had at least 6 months of continuous enrollment after OAC initiation. Multivariable Cox proportional hazards regression was used to assess factors associated with discontinuation. Adjusted hazard ratios (HRs) and 95% CIs were reported. Among 12,129 eligible patients, 8143 (67.1%) initiated warfarin and 3986 (32.9%) initiated direct oral anticoagulants (DOACs). Overall, 47.3% of patients independently discontinued during follow-up (mean number of days of follow-up = 416.6 [SD ± 141.7]) with mean time to discontinuation of 120 days (SD ± 114.7). Patients significantly less likely to discontinue included those taking DOACs versus warfarin (HR, 0.91; 95% CI, 0.86-0.97), older patients (≥65 years vs 18 to 34 years) (HR, 0.32; 95% CI, 0.24-0.43), those with diabetes (HR, 0.84; 95% CI, 0.77-0.90), those with prior stroke/transient ischemic attack (HR, 0.65; 95% CI, 0.56-0.75), those with prior pulmonary embolism (HR, 0.71; 95% CI, 0.58-0.88), and those with congestive heart failure (HR, 0.80; 95% CI, 0.74-0.87). Patients with prior bleeding events were significantly more likely to independently discontinue (HR, 1.20; 95% CI, 1.08-1.34). The risk of independent discontinuation of OAC treatment among NVAF patients was high. Patients on DOACs compared with warfarin and those with several comorbid conditions had significantly lower risk of discontinuation, while those with prior bleeding were more likely to discontinue.

  17. Managing Watersheds as Couple Human-Natural Systems: A Review of Research Opportunities

    Science.gov (United States)

    Cai, X.

    2011-12-01

    Many watersheds around the world are impaired with severe social and environmental problems due to heavy anthropogenic stresses. Humans have transformed hydrological and biochemical processes in watersheds from a stationary to non-stationary status through direct (e.g., water withdrawals) and indirect (e.g., altering vegetation and land cover) interferences. It has been found that in many watersheds that socio-economic drivers, which have caused increasingly intensive alteration of natural processes, have even overcome natural variability to become the dominant factor affecting the behavior of watershed systems. Reversing this trend requires an understanding of the drivers of this intensification trajectory, and needs tremendous policy reform and investment. As stressed by several recent National Research Council (NRC) reports, watershed management will pose an enormous challenge in the coming decades. Correspondingly, the focus of research has started an evolution from the management of reservoir, stormwater and aquifer systems to the management of integrated watershed systems, to which policy instruments designed to make more rational economic use of water resources are likely to be applied. To provide a few examples: reservoir operation studies have moved from a local to a watershed scale in order to consider upstream best management practices in soil conservation and erosion control and downstream ecological flow requirements and water rights; watersheds have been modeled as integrated hydrologic-economic systems with multidisciplinary modeling efforts, instead of traditional isolated physical systems. Today's watershed management calls for a re-definition of watersheds from isolated natural systems to coupled human-natural systems (CHNS), which are characterized by the interactions between human activities and natural processes, crossing various spatial and temporal scales within the context of a watershed. The importance of the conceptual innovation has been

  18. Severe spontaneous vertebral fractures after denosumab discontinuation: three case reports.

    Science.gov (United States)

    Aubry-Rozier, B; Gonzalez-Rodriguez, E; Stoll, D; Lamy, O

    2016-05-01

    Osteoporosis treatments are usually given for a limited period of time in order to balance benefits and risks. We report three cases of postmenopausal women without any previous fragility fracture who presented severe spontaneous vertebral fractures after denosumab discontinuation. We think that the occurrence of these fractures could be explained by the severe rebound effect observed after denosumab discontinuation and that a consensus regarding the end of treatment with denosumab has to be defined.

  19. Corporate Entrepreneurship in SMEs during the Search for Discontinuous Innovations

    DEFF Research Database (Denmark)

    van Geenhuizen, Maurits; Middel, Rick; Lassen, Astrid Heidemann

    2008-01-01

    The present paper illustrates, through three Danish/Dutch case studies, how several of the characteristics connected with SMEs entail significant reasons to make use of corporate entrepreneurship as a search strategy for discontinuous innovation. Characteristic dimensions of corporate entrepreneu......The present paper illustrates, through three Danish/Dutch case studies, how several of the characteristics connected with SMEs entail significant reasons to make use of corporate entrepreneurship as a search strategy for discontinuous innovation. Characteristic dimensions of corporate...

  20. Research progress on criteria for discontinuation of EGFR inhibitor therapy

    Directory of Open Access Journals (Sweden)

    Zhuang HQ

    2012-10-01

    Full Text Available Hong-qing Zhuang, Zhi-yong Yuan, Jun Wang, Ping Wang, Lu-jun Zhao, Bai-lin ZhangDepartment of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin Lung Cancer Center, Tianjin, People's Republic of ChinaAbstract: The clinical success of the epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKI as therapeutic agents has prompted great interest in their further development and clinical testing for a wide variety of malignancies. However, most studies have focused on the efficacy of TKI, and few studies have been done on the criteria for their discontinuation. The current standard for drug discontinuation is “until progression”, based on change in tumor size. However, tumor size is not related to the gene expression which determines the efficacy of TKI in the final analysis, and it is also difficult to make a thorough and correct prediction based on tumor size when the TKI is discontinued. Nevertheless, clinical evaluation of the criteria for TKI discontinuation is still in its early days. Some promising findings have started to emerge. With the improving knowledge of EGFR and its inhibitors, it is expected that the criteria for discontinuation of EGFR inhibitor therapy will become clearer.Keywords: epidermal growth factor receptor, drug discontinuation, acquired drug-resistance

  1. Minimizers with discontinuous velocities for the electromagnetic variational method

    International Nuclear Information System (INIS)

    De Luca, Jayme

    2010-01-01

    The electromagnetic two-body problem has neutral differential delay equations of motion that, for generic boundary data, can have solutions with discontinuous derivatives. If one wants to use these neutral differential delay equations with arbitrary boundary data, solutions with discontinuous derivatives must be expected and allowed. Surprisingly, Wheeler-Feynman electrodynamics has a boundary value variational method for which minimizer trajectories with discontinuous derivatives are also expected, as we show here. The variational method defines continuous trajectories with piecewise defined velocities and accelerations, and electromagnetic fields defined by the Euler-Lagrange equations on trajectory points. Here we use the piecewise defined minimizers with the Lienard-Wierchert formulas to define generalized electromagnetic fields almost everywhere (but on sets of points of zero measure where the advanced/retarded velocities and/or accelerations are discontinuous). Along with this generalization we formulate the generalized absorber hypothesis that the far fields vanish asymptotically almost everywhere and show that localized orbits with far fields vanishing almost everywhere must have discontinuous velocities on sewing chains of breaking points. We give the general solution for localized orbits with vanishing far fields by solving a (linear) neutral differential delay equation for these far fields. We discuss the physics of orbits with discontinuous derivatives stressing the differences to the variational methods of classical mechanics and the existence of a spinorial four-current associated with the generalized variational electrodynamics.

  2. Class of reconstructed discontinuous Galerkin methods in computational fluid dynamics

    International Nuclear Information System (INIS)

    Luo, Hong; Xia, Yidong; Nourgaliev, Robert

    2011-01-01

    A class of reconstructed discontinuous Galerkin (DG) methods is presented to solve compressible flow problems on arbitrary grids. The idea is to combine the efficiency of the reconstruction methods in finite volume methods and the accuracy of the DG methods to obtain a better numerical algorithm in computational fluid dynamics. The beauty of the resulting reconstructed discontinuous Galerkin (RDG) methods is that they provide a unified formulation for both finite volume and DG methods, and contain both classical finite volume and standard DG methods as two special cases of the RDG methods, and thus allow for a direct efficiency comparison. Both Green-Gauss and least-squares reconstruction methods and a least-squares recovery method are presented to obtain a quadratic polynomial representation of the underlying linear discontinuous Galerkin solution on each cell via a so-called in-cell reconstruction process. The devised in-cell reconstruction is aimed to augment the accuracy of the discontinuous Galerkin method by increasing the order of the underlying polynomial solution. These three reconstructed discontinuous Galerkin methods are used to compute a variety of compressible flow problems on arbitrary meshes to assess their accuracy. The numerical experiments demonstrate that all three reconstructed discontinuous Galerkin methods can significantly improve the accuracy of the underlying second-order DG method, although the least-squares reconstructed DG method provides the best performance in terms of both accuracy, efficiency, and robustness. (author)

  3. The risk of suicide after clozapine discontinuation: Cause for concern.

    Science.gov (United States)

    Patchan, Kathleen M; Richardson, Charles; Vyas, Gopal; Kelly, Deanna L

    2015-11-01

    Clozapine is a second-generation antipsychotic that has been shown to reduce suicidal ideation and suicidal behaviors in patients with schizophrenia. However, it is underutilized because of its serious side effects. We describe 3 patients with a history of suicide ideation and attempts who were successfully treated and maintained in the community without suicidal tendencies while taking clozapine. All 3 patients, men in their 20s, discontinued clozapine because of side effects and subsequently committed suicide. We also review the literature on clozapine's effects on suicidality. In these 3 cases, suicide followed abrupt discontinuation of clozapine or transition to another antipsychotic. This case series is the first of its kind to document the risk of suicide when clozapine is discontinued. The decision to discontinue clozapine should be made carefully, especially because clozapine is considered the treatment of last resort for patients with treatment-resistant schizophrenia and suicidal ideation. We stress the importance of minimizing the risk of abrupt clozapine discontinuation and recommend further evaluation of suicide ideation and attempts when clozapine is discontinued.

  4. Visualization of Natural Convection Heat Transfer on a Single Sphere using the Electroplating System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Young; Chung, Bum Jin [Kyunghee University, Yongin (Korea, Republic of)

    2016-05-15

    The natural convective flows on outer sphere rise along surface. At top of sphere, the flows are lifted-up plume shape. For laminar flows, the local heat transfer shows maximum at the bottom of sphere and a monotonic decreases as flows approached to the top. The laminar natural convection heat transfer on a single sphere has been studied experimentally and numerically by several researchers. However, relatively less study has been performed for turbulent flows as it requires large facilities to achieve high Rayleigh numbers. The flows, which occur transition, is hard to experiment because of unstable. This study tried measurement of heat transfer and visualization external natural convection on a single sphere. The basic idea is that the plating patterns of copper on the sphere in mass transfer system will reveal the amount of heat transfer according to angular distance from the bottom. This study simulated natural convection on a single sphere and performed a mass transfer experiment using heat and mass transfer analogy concept. For visualization experiment, streak form plating pattern was observed. In this case, it seems that turbulence sets on the top of sphere and increases local heat transfer.

  5. Influence of forest management systems on natural resource use and provision of ecosystem services in Tanzania.

    Science.gov (United States)

    Strauch, Ayron M; Rurai, Masegeri T; Almedom, Astier M

    2016-09-15

    Social, religious and economic facets of rural livelihoods in Sub-Saharan Africa are heavily dependent on natural resources, but improper resource management, drought, and social instability frequently lead to their unsustainable exploitation. In rural Tanzania, natural resources are often governed locally by informal systems of traditional resource management (TRM), defined as cultural practices developed within the context of social and religious institutions over hundreds of years. However, following independence from colonial rule, centralized governments began to exercise jurisdictional control over natural resources. Following decades of mismanagement that resulted in lost ecosystem services, communities demanded change. To improve resource protection and participation in management among stakeholders, the Tanzanian government began to decentralize management programs in the early 2000s. We investigated these two differing management approaches (traditional and decentralized government) in Sonjo communities, to examine local perceptions of resource governance, management influences on forest use, and their consequences for forest and water resources. While 97% of households understood the regulations governing traditionally-managed forests, this was true for only 39% of households for government-managed forests, leading to differences in forest use. Traditional management practices resulted in improved forest condition and surface water quality. This research provides an essential case study demonstrating the importance of TRM in shaping decision frameworks for natural resource planning and management. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Natural hazards in the formal education system in Serbia - facts and experiences

    Science.gov (United States)

    Ćalić, Jelena; Kovačević-Majkić, Jelena; Panić, Milena; Milošević, Marko V.; Miljanović, Dragana

    2015-04-01

    We present the current situation in the Serbian formal education system with respect to the issues of natural disasters and resilience of the society. The role of obligatory education (through primary and secondary schools) is considered essential, thanks to the fact that the majority of the population acquire this type of education. Although a certain number of natural hazards is covered by the curricula of several subjects (mainly Geography), the hazards are treated almost exclusively as natural processes of increased intensity, and not through their impact on society and its transformation. Therefore we cannot say that the disaster risk reduction is included in the formal curriculum. The analysis covers three main aspects: the legal framework (the background which enables the formal teaching about natural disasters), the present curricula (seen through the contents of geography textbooks) and the present state of the disaster-related knowledge among the pupils. The latter is shown through the results of the poll survey carried out among the pupils in earthquake-struck town of Kraljevo (M 5.4 in 2010). Although the children are highly aware of the need for better coverage of risk reduction in their education, they are not aware that their reactions during the earthquake event were mostly improper. Disaster-related professional trainings for teachers, approved by the Ministry of Education, aim to motivate teachers to include the disaster risk reduction issues into the teaching process even before the formal inclusion of these issues into the curricula.

  7. Status of the IAEA coordinated research project on natural circulation phenomena, modelling, and reliability of passive systems that utilize natural circulation

    International Nuclear Information System (INIS)

    Reyes, J.N. Jr.; Cleveland, J.; Aksan, N.

    2004-01-01

    The International Atomic Energy Agency (IAEA) has established a Coordinated Research Project (CRP) titled ''Natural Circulation Phenomena, Modelling and Reliability of Passive Safety Systems that Utilize Natural Circulation. '' This work has been organized within the framework of the IAEA Department of Nuclear Energy's Technical Working Groups for Advanced Technologies for Light Water Reactors and Heavy Water Reactors (the TWG-LWR and the TWG-HWR). This CRP is part of IAEA's effort to foster international collaborations that strive to improve the economic performance of future water-cooled nuclear power plants while meeting stringent safety requirements. Thus far, IAEA has established 12 research agreements with organizations from industrialized Member States and 3 research contracts with organizations from developing Member States. The objective of the CRP is to enhance our understanding of natural circulation phenomena in water-cooled reactors and passive safety systems. The CRP participants are particularly interested in establishing a natural circulation and passive safety system thermal hydraulic database that can be used to benchmark computer codes for advanced reactor systems design and safety analysis. An important aspect of this CRP relates to developing methodologies to assess the reliability of passive safety systems in advanced reactor designs. This paper describes the motivation and objectives of the CRP, the research plan, and the role of each of the participating organizations. (author)

  8. Effects of age, parity, and device type on complications and discontinuation of intrauterine devices.

    Science.gov (United States)

    Aoun, Joelle; Dines, Virginia A; Stovall, Dale W; Mete, Mihriye; Nelson, Casey B; Gomez-Lobo, Veronica

    2014-03-01

    To conduct an analysis of intrauterine device (IUD)-related outcomes including expulsion, contraceptive failure, and early discontinuation and to compare these outcomes in regard to age, parity, and IUD type. This was a multicenter retrospective chart review of adolescents and women aged 13-35 years who had an IUD inserted for contraception between June 2008 and June 2011. A total of 2,523 patients' charts were reviewed. Of these, 2,138 patients were included in our analysis. After a mean follow-up of 37±11 months, the overall rates of IUD expulsion and pregnancy were 6% and 1%, respectively, and were not significantly different by age or parity. Intrauterine device discontinuation rates were 19% at 12 months and 41% after a mean follow-up of 37 months. Despite similar rates of IUD discontinuation between age groups at 12 months of use, teenagers and young women aged 13-19 years were more likely to request early discontinuation at the end of the total follow-up period. No significant difference was noted in pelvic inflammatory disease rates (2%) based on age. After adjusting for age and parity, we found that copper IUD users were more likely to experience expulsion and contraception failure compared with levonorgestrel intrauterine system users (hazard ratios 1.62, 95% confidence interval [CI] 1.06-2.50 and hazard ratios 4.89, 95% CI 2.02-11.80, respectively). Similar to adults, IUD use in adolescents and nulliparous women is effective and associated with low rates of serious complications. Health practitioners should therefore consider IUDs for contraception in all females. Teenagers and young women are more likely to request premature discontinuation of their IUDs and may benefit from additional counseling.

  9. Abrupt opium discontinuation has no significant triggering effect on acute myocardial infarction.

    Science.gov (United States)

    Masoomi, Mohammad; Zare, Jahangir; Nasri, Hamidreza; Mirzazadeh, Ali; Sheikhvatan, Mehrdad

    2011-04-01

    A deleterious effect of withdrawal symptoms due to abrupt discontinuation of opium on the cardiovascular system is one of the recent interesting topics in the cardiovascular field. The current study hypothesized that the withdrawal syndrome due to discontinuing opium might be an important trigger for the appearance of acute myocardial infarction. Eighty-one opium-addicted individuals who were candidates for cardiovascular clinical evaluation and consecutively hospitalized in the coronary care unit (CCU) ward of Shafa Hospital in Kerman between January and July 2009 were included in the study and categorized in the case group, including patients experiencing withdrawal symptoms within 6-12 h after the reduced or discontinued use of opium according to the Diagnostic and Statistical Manual of Mental Disorders-revised IV version (DSM-IV-R) criteria for opium dependence and withdrawal, and the control group, without opium withdrawal symptoms. The appearance of acute myocardial infarction was compared between the two groups using multivariable regression models. Acute myocardial infarction occurred in 50.0% of those with withdrawal symptoms and in 45.1% of patients without evidence of opium withdrawal (P = 0.669). Multivariable analysis showed that opium withdrawal symptoms were not a trigger for acute myocardial infarction adjusting for demographic characteristics, marital status, education level and common coronary artery disease risk profiles [odds ratio (OR) = 0.920, 95% confidence interval (CI) = 0.350-2.419, P = 0.866]. Also, daily dose of opium before reducing or discontinuing use did not predict the appearance of myocardial infarction in the presence of confounder variables (OR = 0.975, 95% CI = 0.832-1.143, P = 0.755). Withdrawal syndrome due to abrupt discontinuation of opium does not have a triggering role for appearance of acute myocardial infarction.

  10. Patient Outcomes in Dose Reduction or Discontinuation of Long-Term Opioid Therapy: A Systematic Review.

    Science.gov (United States)

    Frank, Joseph W; Lovejoy, Travis I; Becker, William C; Morasco, Benjamin J; Koenig, Christopher J; Hoffecker, Lilian; Dischinger, Hannah R; Dobscha, Steven K; Krebs, Erin E

    2017-08-01

    Expert guidelines recommend reducing or discontinuing long-term opioid therapy (LTOT) when risks outweigh benefits, but evidence on the effect of dose reduction on patient outcomes has not been systematically reviewed. To synthesize studies of the effectiveness of strategies to reduce or discontinue LTOT and patient outcomes after dose reduction among adults prescribed LTOT for chronic pain. MEDLINE, EMBASE, PsycINFO, CINAHL, and the Cochrane Library from inception through April 2017; reference lists; and expert contacts. Original research published in English that addressed dose reduction or discontinuation of LTOT for chronic pain. Two independent reviewers extracted data and assessed study quality using the U.S. Preventive Services Task Force quality rating criteria. All authors assessed evidence quality using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. Prespecified patient outcomes were pain severity, function, quality of life, opioid withdrawal symptoms, substance use, and adverse events. Sixty-seven studies (11 randomized trials and 56 observational studies) examining 8 intervention categories, including interdisciplinary pain programs, buprenorphine-assisted dose reduction, and behavioral interventions, were found. Study quality was good for 3 studies, fair for 13 studies, and poor for 51 studies. Many studies reported dose reduction, but rates of opioid discontinuation ranged widely across interventions and the overall quality of evidence was very low. Among 40 studies examining patient outcomes after dose reduction (very low overall quality of evidence), improvement was reported in pain severity (8 of 8 fair-quality studies), function (5 of 5 fair-quality studies), and quality of life (3 of 3 fair-quality studies). Heterogeneous interventions and outcome measures; poor-quality studies with uncontrolled designs. Very low quality evidence suggests that several types of interventions may be effective to reduce or

  11. Characterization of discontinuities in an argillaceous medium (Tournemire site): key questions related to safety assessment of radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera Nunez, J. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

    2001-07-01

    The safety assessment of deep radioactive waste disposal in argillaceous medium concerns the evaluation of the possibilities and transfer processes through this geological barrier. Generally, this material is characterized by a very low permeability. However, faults and fractures may affect this medium and consequently it is important to analyse the transfer possibilities along these discontinuities. The first phase of this evaluation is the detection or survey of the fractures, and the second one is the evaluation of their hydraulic properties. A discontinuity is not a synonymous of fluid transfer, which in turn may be inhomogeneous along the same fracture. The well-compacted Tournemire argillaceous medium (argilites and marls) is affected by some faults and fractures of natural (tectonic) and artificial (excavation) origin. The natural fractures are of different scales: major regional faults that limit blocks, secondary fault and fractured zones that affect the blocks, and local fractures and micro-fractures. These discontinuities are studied from the surface analyses, transversal boreholes and drifts. Geophysical methods are tested to detect these discontinuities to different scales. The present-day fluids are shown in some fractured sectors that allow us to analyse the possibilities of fluid transfer along these discontinuities. The fracture analyses show that permeability or transmissivity properties may change along the discontinuities. A decametric fluid transfer is shown along some fractures; however, their integration in a larger scale is not yet analysed. It is necessary to understand how the transfer in the near field may be connected to the possible far field transfer, or these transfers are not possible through the argillaceous medium. (author)

  12. Characterization of discontinuities in an argillaceous medium (Tournemire site): key questions related to safety assessment of radioactive waste disposal

    International Nuclear Information System (INIS)

    Cabrera Nunez, J.

    2001-01-01

    The safety assessment of deep radioactive waste disposal in argillaceous medium concerns the evaluation of the possibilities and transfer processes through this geological barrier. Generally, this material is characterized by a very low permeability. However, faults and fractures may affect this medium and consequently it is important to analyse the transfer possibilities along these discontinuities. The first phase of this evaluation is the detection or survey of the fractures, and the second one is the evaluation of their hydraulic properties. A discontinuity is not a synonymous of fluid transfer, which in turn may be inhomogeneous along the same fracture. The well-compacted Tournemire argillaceous medium (argilites and marls) is affected by some faults and fractures of natural (tectonic) and artificial (excavation) origin. The natural fractures are of different scales: major regional faults that limit blocks, secondary fault and fractured zones that affect the blocks, and local fractures and micro-fractures. These discontinuities are studied from the surface analyses, transversal boreholes and drifts. Geophysical methods are tested to detect these discontinuities to different scales. The present-day fluids are shown in some fractured sectors that allow us to analyse the possibilities of fluid transfer along these discontinuities. The fracture analyses show that permeability or transmissivity properties may change along the discontinuities. A decametric fluid transfer is shown along some fractures; however, their integration in a larger scale is not yet analysed. It is necessary to understand how the transfer in the near field may be connected to the possible far field transfer, or these transfers are not possible through the argillaceous medium. (author)

  13. Obedience to compliance programs and independence for electricity and natural gas system operators. 2009 report

    International Nuclear Information System (INIS)

    2009-12-01

    In France, system operators belong to groups that also conduct business in the energy sector, in fields governed by competition rules. They could therefore be tempted to use their privileged position to their group's benefit, which would disadvantage end consumers. Non-discriminatory access to electricity and gas transmission and distribution networks is at the core of the market opening to competition approach implemented by the European Union since the end of the 1990's. EU and national enactments in force highlight two tools to ensure nondiscrimination: compliance programmes and independence of system operators with regard to their parent companies. Firstly, compliance programs contain measures taken to ensure that discrimination is completely excluded and that their application is subject to appropriate monitoring. Secondly, system operator independence plays a part in preventing discrimination against competitors with other business activities (generation, supply, etc.) within the same group. In application of these enactments, every electricity or natural gas transmission or distribution system operator serving more than 100,000 customers provided CRE, the Energy Regulatory Commission, with their annual reports on the application of their compliance programs. This document is CRE's 2009 report about compliance programmes and independence of electricity and natural gas system operators. Its content can be summarized as follows: 1 - system operator independence serving consumers: Non-discriminatory access to networks is essential for the development of competitive markets, System operator compliance programs and independence act as a guarantee of nondiscrimination, The legal context in which these issues are addressed is set to change in the near future; 2 - A high level of obedience to compliance programs: The continued efforts of system operators prevent discrimination, CR E has assessed distribution system operators by means of a mystery

  14. Development of a BR-UASB-DHS system for natural rubber processing wastewater treatment.

    Science.gov (United States)

    Watari, Takahiro; Thanh, Nguyen Thi; Tsuruoka, Natsumi; Tanikawa, Daisuke; Kuroda, Kyohei; Huong, Nguyen Lan; Tan, Nguyen Minh; Hai, Huynh Trung; Hatamoto, Masashi; Syutsubo, Kazuaki; Fukuda, Masao; Yamaguchi, Takashi

    2015-11-21

    Natural rubber processing wastewater contains high concentrations of organic compounds, nitrogen, and other contaminants. In this study, a treatment system composed of a baffled reactor (BR), an upflow anaerobic sludge blanket (UASB) reactor, and a downflow hanging sponge (DHS) reactor was used to treat natural rubber processing wastewater in Vietnam. The BR showed good total suspended solids removal of 47.6%, as well as acidification of wastewater. The UASB reactor achieved a high chemical oxygen demand (COD) removal efficiency of 92.7% ± 2.3% and energy recovery in the form of methane with an organic loading rate of 12.2 ± 6.6 kg-COD·m -3 ·day -1 . The DHS reactor showed a high performance in residual organic matter removal from UASB effluent. In total, the system achieved high-level total COD removal of 98.6% ± 1.2% and total suspended solids removal of 98.0% ± 1.4%. Massive parallel 16S rRNA gene sequencing of the retained sludge in the UASB reactor showed the predominant microbial phyla to be Bacteroidetes, Firmicutes, Proteobacteria, WWE1, and Euryarchaeota. Uncultured bacteria belonging to the phylum Bacteroidetes and Phylum WWE1 were predominant in the UASB reactor. This microbial assemblage utilizes the organic compounds contained in natural rubber processing wastewater. In addition, the methane-producing archaea Methanosaeta sp. and Methanolinea sp. were detected.

  15. Investigation of the ventilation performance of an integrated day lighting natural ventilation system

    International Nuclear Information System (INIS)

    Ahmed, S.; Abdul Rahman, S.; Ahmed, A.Z.

    2006-01-01

    Natural ventilation and daylighting are two passive strategies that can improve the indoor performance as well as reduce energy consumption in buildings. Both strategies when used appropriately, increase indoor quality and comport. In terms of energy costs, daylighting can significantly reduce artificial lighting as well as heat dissipated from the resulting fixtures while natural ventilation can minimize the need for air-conditioning. A study is currently being conducted to develop a system that integrates these two passive strategies, to be used specifically for buildings in Malaysia. The initial proposed integrated models are based on similar studies already conducted but with appropriate modifications for tropical climates. This paper will present some results of the ventilation performance of the proposed integrated system model, particularly the airflow distribution patterns and air speed, inside a naturally ventilated room. A CFD simulation software was used to investigate the optimum size of the integrated model with regards to interior ventilation performance. The simulations also included single sided and cross ventilated openings

  16. Information and entropy theory for the sustainability of coupled human and natural systems

    Directory of Open Access Journals (Sweden)

    Audrey L. Mayer

    2014-09-01

    Full Text Available For coupled human and natural systems (CHANS, sustainability can be defined operationally as a feasible, desirable set of flows (material, currency, information, energy, individuals, etc. that can be maintained despite internal changes and changes in the environment. Sustainable development can be defined as the process by which CHANS can be moved toward sustainability. Specific indicators that give insight into the structure and behavior of feedbacks in CHANS are of particular interest because they would aid in the sustainable management of these systems through an understanding of the structures that govern system behavior. However, the use of specific feedbacks as monitoring tools is rare, possibly because of uncertainties regarding the nature of their dynamics and the diversity of types of feedbacks encountered in these systems. An information theory perspective may help to rectify this situation, as evidenced by recent research in sustainability science that supports the use of unit-free measures such as Shannon entropy and Fisher information to aggregate disparate indicators. These measures have been used for spatial and temporal datasets to monitor progress toward sustainability targets. Here, we provide a review of information theory and a theoretical framework for studying the dynamics of feedbacks in CHANS. We propose a combination of information-based indices that might productively inform our sustainability goals, particularly when related to key feedbacks in CHANS.

  17. Silver engineered nanoparticles in freshwater systems - Likely fate and behaviour through natural attenuation processes.

    Science.gov (United States)

    Shevlin, David; O'Brien, Niall; Cummins, Enda

    2018-04-15

    Growth in the nanotechnology sector is likely introducing unnatural formations of materials on the nanoscale (10 -9 m) to the environment. Disposal and degradation of products incorporating engineered nanomaterials (ENMs) are likely being released into natural aquatic systems un-intentionally primarily via waste water effluents. The fate and behaviour of metallic based nanoparticles (NPs) such as silver (Ag) in aquatic waters is complex with high levels of variability and uncertainty. In-situ physical, biological and chemical (natural attenuation) processes are likely to influence ENM fate and behaviour in freshwater systems. Surfaced functionalized particles may inhibit or limit environmental transformations which influence particle aggregation, mobility, dissolution and eco-toxic potential. This paper focuses on ENM characteristics and the influence of physical, chemical and biological processes occurring in aquatic systems that are likely to impact metallic ENMs fate. A focus on silver NPs (while for comparison, reporting about other metallic ENMs as appropriate) released to aquatic systems is discussed relating to their likely fate and behaviour in this dynamic and complex environment. This paper further highlights the need for specific risk assessment approaches for metallic ENMs and puts this into context with regard to informing environmental policy and potential NP influence on environmental/human health. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Cogent Confabulation based Expert System for Segmentation and Classification of Natural Landscape Images

    Directory of Open Access Journals (Sweden)

    BRAOVIC, M.

    2017-05-01

    Full Text Available Ever since there has been an increase in the number of automatic wildfire monitoring and surveillance systems in the last few years, natural landscape images have been of great importance. In this paper we propose an expert system for fast segmentation and classification of regions on natural landscape images that is suitable for real-time applications. We focus primarily on Mediterranean landscape images since the Mediterranean area and areas with similar climate are the ones most associated with high wildfire risk. The proposed expert system is based on cogent confabulation theory and knowledge bases that contain information about local and global features, optimal color spaces suitable for classification of certain regions, and context of each class. The obtained results indicate that the proposed expert system significantly outperforms well-known classifiers that it was compared against in both accuracy and speed, and that it is effective and efficient for real-time applications. Additionally, we present a FESB MLID dataset on which we conducted our research and that we made publicly available.

  19. MODELING THE AMBIENT CONDITION EFFECTS OF AN AIR-COOLED NATURAL CIRCULATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Rui; Lisowski, Darius D.; Bucknor, Matthew; Kraus, Adam R.; Lv, Qiuping

    2017-07-02

    The Reactor Cavity Cooling System (RCCS) is a passive safety concept under consideration for the overall safety strategy of advanced reactors such as the High Temperature Gas-Cooled Reactor (HTGR). One such variant, air-cooled RCCS, uses natural convection to drive the flow of air from outside the reactor building to remove decay heat during normal operation and accident scenarios. The Natural convection Shutdown heat removal Test Facility (NSTF) at Argonne National Laboratory (“Argonne”) is a half-scale model of the primary features of one conceptual air-cooled RCCS design. The facility was constructed to carry out highly instrumented experiments to study the performance of the RCCS concept for reactor decay heat removal that relies on natural convection cooling. Parallel modeling and simulation efforts were performed to support the design, operation, and analysis of the natural convection system. Throughout the testing program, strong influences of ambient conditions were observed in the experimental data when baseline tests were repeated under the same test procedures. Thus, significant analysis efforts were devoted to gaining a better understanding of these influences and the subsequent response of the NSTF to ambient conditions. It was determined that air humidity had negligible impacts on NSTF system performance and therefore did not warrant consideration in the models. However, temperature differences between the building exterior and interior air, along with the outside wind speed, were shown to be dominant factors. Combining the stack and wind effects together, an empirical model was developed based on theoretical considerations and using experimental data to correlate zero-power system flow rates with ambient meteorological conditions. Some coefficients in the model were obtained based on best fitting the experimental data. The predictive capability of the empirical model was demonstrated by applying it to the new set of experimental data. The

  20. Model documentation: Natural Gas Transmission and Distribution Model of the National Energy Modeling System; Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-24

    The Natural Gas Transmission and Distribution Model (NGTDM) is a component of the National Energy Modeling System (NEMS) used to represent the domestic natural gas transmission and distribution system. NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the Energy Information Administration (EIA) and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. This report documents the archived version of NGTDM that was used to produce the natural gas forecasts used in support of the Annual Energy Outlook 1994, DOE/EIA-0383(94). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. It is intended to fulfill the legal obligation of the EIA to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). This report represents Volume 1 of a two-volume set. (Volume 2 will report on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.) Subsequent chapters of this report provide: (1) an overview of the NGTDM (Chapter 2); (2) a description of the interface between the National Energy Modeling System (NEMS) and the NGTDM (Chapter 3); (3) an overview of the solution methodology of the NGTDM (Chapter 4); (4) the solution methodology for the Annual Flow Module (Chapter 5); (5) the solution methodology for the Distributor Tariff Module (Chapter 6); (6) the solution methodology for the Capacity Expansion Module (Chapter 7); (7) the solution methodology for the Pipeline Tariff Module (Chapter 8); and (8) a description of model assumptions, inputs, and outputs (Chapter 9).