Kinematic approach to off-diagonal geometric phases of nondegenerate and degenerate mixed states

International Nuclear Information System (INIS)

Tong, D.M.; Oh, C.H.; Sjoeqvist, Erik; Filipp, Stefan; Kwek, L.C.

2005-01-01

Off-diagonal geometric phases have been developed in order to provide information of the geometry of paths that connect noninterfering quantal states. We propose a kinematic approach to off-diagonal geometric phases for pure and mixed states. We further extend the mixed-state concept proposed in [Phys. Rev. Lett. 90, 050403 (2003)] to degenerate density operators. The first- and second-order off-diagonal geometric phases are analyzed for unitarily evolving pairs of pseudopure states

New Wang-Landau approach to obtain phase diagrams for multicomponent alloys

Science.gov (United States)

Takeuchi, Kazuhito; Tanaka, Ryohei; Yuge, Koretaka

2017-10-01

We develop an approach to apply the Wang-Landau algorithm to multicomponent alloys in a semi-grand-canonical ensemble. Although the Wang-Landau algorithm has great advantages over conventional sampling methods, there are few applications to alloys. This is because calculating compositions in a semi-grand-canonical ensemble via the Wang-Landau algorithm requires a multidimensional density of states in terms of total energy and compositions, and constructing it is difficult from the viewpoints of both implementation and computational cost. In this study, we develop a simple approach to calculate the alloy phase diagram based on the Wang-Landau algorithm, and show that a number of one-dimensional densities of states could lead to compositions in a semi-grand-canonical ensemble as a multidimensional density of states could. Finally, we apply the present method to Cu-Au and Pd-Rh alloys and confirm that the present method successfully describes the phase diagram with high efficiency, validity, and accuracy.

A phase-space approach to atmospheric dynamics based on observational data. Theory and applications

International Nuclear Information System (INIS)

Wang Risheng.

1994-01-01

This thesis is an attempt to develop systematically a phase-space approach to the atmospheric dynamics based on the theoretical achievement and application experiences in nonlinear time-series analysis. In particular, it is concerned with the derivation of quantities for describing the geometrical structure of the observed dynamics in phase-space (dimension estimation) and the examination of the observed atmospheric fluctuations in the light of phase-space representation. The thesis is, therefore composed of three major parts, i.e. an general survey of the theory of statistical approaches to dynamic systems, the methodology designed for the present study and specific applications with respect to dimension estimation and to a phase-space analysis of the tropical stratospheric quasi-biennial oscillation. (orig./KW)

A Development-Oriented IS Evaluation Approach: Case Demonstration for DSS

Directory of Open Access Journals (Sweden)

Shah J Miah

2012-04-01

Full Text Available Information systems (IS development research needs a broader conceptual lens for evaluating IS design qualities. Most conventional IS evaluation approaches are focused on narrow objectives, such as the process and content rather than the development process as a whole. This paper describes a qualitative evaluation of a new approach that extends evaluation strategies to incorporate development phases, specifically within decision support systems (DSS development. The conceptual approach is based on a mental model from the design science research paradigm and evaluates DSS development at various design checkpoints. This paper also describes qualitative findings on the applicability of the conceptual approach in a socio-technical design context.

The Elements of Language Curriculum: A Systematic Approach to Program Development.

Science.gov (United States)

Brown, James Dean

A systematic approach to second language curriculum development is outlined, enumerating the phases and activities involved in developing and implementing a sound and effective language program. The first chapter describes a system whereby all language teaching activities can be classified into approaches, syllabuses, techniques, exercises, or…

Development of Human Face Literature Database Using Text Mining Approach: Phase I.

Science.gov (United States)

Kaur, Paramjit; Krishan, Kewal; Sharma, Suresh K

2018-06-01

The face is an important part of the human body by which an individual communicates in the society. Its importance can be highlighted by the fact that a person deprived of face cannot sustain in the living world. The amount of experiments being performed and the number of research papers being published under the domain of human face have surged in the past few decades. Several scientific disciplines, which are conducting research on human face include: Medical Science, Anthropology, Information Technology (Biometrics, Robotics, and Artificial Intelligence, etc.), Psychology, Forensic Science, Neuroscience, etc. This alarms the need of collecting and managing the data concerning human face so that the public and free access of it can be provided to the scientific community. This can be attained by developing databases and tools on human face using bioinformatics approach. The current research emphasizes on creating a database concerning literature data of human face. The database can be accessed on the basis of specific keywords, journal name, date of publication, author's name, etc. The collected research papers will be stored in the form of a database. Hence, the database will be beneficial to the research community as the comprehensive information dedicated to the human face could be found at one place. The information related to facial morphologic features, facial disorders, facial asymmetry, facial abnormalities, and many other parameters can be extracted from this database. The front end has been developed using Hyper Text Mark-up Language and Cascading Style Sheets. The back end has been developed using hypertext preprocessor (PHP). The JAVA Script has used as scripting language. MySQL (Structured Query Language) is used for database development as it is most widely used Relational Database Management System. XAMPP (X (cross platform), Apache, MySQL, PHP, Perl) open source web application software has been used as the server.The database is still under the

EMR implementation: big bang or a phased approach?

Science.gov (United States)

Owens, Kathleen

2008-01-01

There are two major strategies to implementing an EMR: the big-bang approach and the phased, or incremental, approach. Each strategy has pros and cons that must be considered. This article discusses these approaches and the risks and benefits of each as well as some training strategies that can be used with either approach.

A phase space approach to wave propagation with dispersion.

Science.gov (United States)

Ben-Benjamin, Jonathan S; Cohen, Leon; Loughlin, Patrick J

2015-08-01

A phase space approximation method for linear dispersive wave propagation with arbitrary initial conditions is developed. The results expand on a previous approximation in terms of the Wigner distribution of a single mode. In contrast to this previously considered single-mode case, the approximation presented here is for the full wave and is obtained by a different approach. This solution requires one to obtain (i) the initial modal functions from the given initial wave, and (ii) the initial cross-Wigner distribution between different modal functions. The full wave is the sum of modal functions. The approximation is obtained for general linear wave equations by transforming the equations to phase space, and then solving in the new domain. It is shown that each modal function of the wave satisfies a Schrödinger-type equation where the equivalent "Hamiltonian" operator is the dispersion relation corresponding to the mode and where the wavenumber is replaced by the wavenumber operator. Application to the beam equation is considered to illustrate the approach.

A complementarity-based approach to phase in finite-dimensional quantum systems

International Nuclear Information System (INIS)

Klimov, A B; Sanchez-Soto, L L; Guise, H de

2005-01-01

We develop a comprehensive theory of phase for finite-dimensional quantum systems. The only physical requirement we impose is that phase is complementary to amplitude. To implement this complementarity we use the notion of mutually unbiased bases, which exist for dimensions that are powers of a prime. For a d-dimensional system (qudit) we explicitly construct d+1 classes of maximally commuting operators, each one consisting of d-1 operators. One of these classes consists of diagonal operators that represent amplitudes (or inversions). By finite Fourier transformation, it is mapped onto ladder operators that can be appropriately interpreted as phase variables. We discuss examples of qubits and qutrits, and show how these results generalize previous approaches

A phased approach to cooperative environmental management R ampersand D projects with Russian institutes

International Nuclear Information System (INIS)

Matalucci, R.V.; Albert, T.E.

1994-01-01

An important aspect of technology exchange between the US and the Former Society Union (FSU) countries is the identification and implementation of cooperative projects that are mutually beneficial. The US Department of Energy (DOE) and its national laboratories have established a four-phase approach to identify and further develop Russian technologies that could contribute to solving DOE environmental management problems. Following an initial screening and identification of potential technologies, the country-to-country interaction is formally initiated in the first phase through a small-scale pilot project study. This phase consists of an evaluation of the specific technology for DOE applications, and provides an opportunity for both US and Russian scientists and engineers to validate the use of the technology for a specific DOE requirement. The successful completion of this phase establishes the basis for continuing the technology development into the second phase, which includes laboratory testing in Russia. In the third phase, the technology is laboratory tested in the US, most likely at those DOE national laboratories having the capability and greatest interest in the particular technology area. The fourth and final phase consist of a commercialization process that establishes a partnership with a US business to finalize development of the technology and to prepare for implementation within the DOE complex. An example of this phased approach is a current high-level waste separation cooperative project between the Khlopin Radium Institute and the DOE through Sandia National Laboratories (SNL) and Science Applications International Corporation (SAIC). This effort has not only enhanced separations technology for the DOE, but has also provided an example of a working process for future cooperative projects

An Application of Graphical Approach to Construct Multiple Testing Procedure in a Hypothetical Phase III Design

Directory of Open Access Journals (Sweden)

Naitee eTing

2014-01-01

Full Text Available Many multiple testing procedures (MTP have been developed in recent years. Among these new procedures, the graphical approach is flexible and easy to communicate with non-statisticians. A hypothetical Phase III clinical trial design is introduced in this manuscript to demonstrate how graphical approach can be applied in clinical product development. In this design, an active comparator is used. It is thought that this test drug under development could potentially be superior to this comparator. For comparison of efficacy, the primary endpoint is well established and widely accepted by regulatory agencies. However, an important secondary endpoint based on Phase II findings looks very promising. The target dose may have a good opportunity to deliver superiority to the comparator. Furthermore, a lower dose is included in case the target dose may demonstrate potential safety concerns. This Phase III study is designed as a non-inferiority trial with two doses, and two endpoints. This manuscript will illustrate how graphical approach is applied to this design in handling multiple testing issues.

Modelling of Hydrophilic Interaction Liquid Chromatography Stationary Phases Using Chemometric Approaches

Science.gov (United States)

Ortiz-Villanueva, Elena; Tauler, Romà

2017-01-01

Metabolomics is a powerful and widely used approach that aims to screen endogenous small molecules (metabolites) of different families present in biological samples. The large variety of compounds to be determined and their wide diversity of physical and chemical properties have promoted the development of different types of hydrophilic interaction liquid chromatography (HILIC) stationary phases. However, the selection of the most suitable HILIC stationary phase is not straightforward. In this work, four different HILIC stationary phases have been compared to evaluate their potential application for the analysis of a complex mixture of metabolites, a situation similar to that found in non-targeted metabolomics studies. The obtained chromatographic data were analyzed by different chemometric methods to explore the behavior of the considered stationary phases. ANOVA-simultaneous component analysis (ASCA), principal component analysis (PCA) and partial least squares regression (PLS) were used to explore the experimental factors affecting the stationary phase performance, the main similarities and differences among chromatographic conditions used (stationary phase and pH) and the molecular descriptors most useful to understand the behavior of each stationary phase. PMID:29064436

Derivation of quantitative acceptance criteria for disposal of radioactive waste to near surface facilities: Development and implementation of an approach for the post-closure phase

International Nuclear Information System (INIS)

Torres, C.

2000-01-01

The International Atomic Energy Agency has established a project to develop and illustrate, through practical examples, an approach that allows the derivation of quantitative waste acceptance criteria for near surface disposal of radioactive waste. The first phase focussed on the derivation of example post-closure safety waste acceptance criteria through the use of a safety assessment approach that allows for the derivation of values in a clear and well documented manner. The approach consists of five steps: the specification of the assessment context; the description of the disposal system; the development and justification of scenarios; the formulation and implementation of models; and the calculation and derivation of example values. The approach has been successfully used to derive activity values for the disposal of radioactive waste to illustrative near surface facilities. (author)

Development of injection moulded, ultrasonically welded immiscible phase filtration devices

DEFF Research Database (Denmark)

Kistrup, Kasper

for ultrasonic welding, suitable for microfluidic systems. A methodology has been established where energy directors can be quickly added to existing mould inserts, using laser micromachining. The produced device was performance tested by isolating methicillin-resistant Staphylococcus aureus from bovine whole....... The device appliesmagnetic bead-based solid-phase extraction for nucleic acid extraction from biological samples, using the immiscible phase filtration (IPF) approach. Device development has employed injection moulding for part fabrication and ultrasonic welding for bonding. Rapid prototyping...

Nanoscale multiphase phase field approach for stress- and temperature-induced martensitic phase transformations with interfacial stresses at finite strains

Science.gov (United States)

Basak, Anup; Levitas, Valery I.

2018-04-01

A thermodynamically consistent, novel multiphase phase field approach for stress- and temperature-induced martensitic phase transformations at finite strains and with interfacial stresses has been developed. The model considers a single order parameter to describe the austenite↔martensitic transformations, and another N order parameters describing N variants and constrained to a plane in an N-dimensional order parameter space. In the free energy model coexistence of three or more phases at a single material point (multiphase junction), and deviation of each variant-variant transformation path from a straight line have been penalized. Some shortcomings of the existing models are resolved. Three different kinematic models (KMs) for the transformation deformation gradient tensors are assumed: (i) In KM-I the transformation deformation gradient tensor is a linear function of the Bain tensors for the variants. (ii) In KM-II the natural logarithms of the transformation deformation gradient is taken as a linear combination of the natural logarithm of the Bain tensors multiplied with the interpolation functions. (iii) In KM-III it is derived using the twinning equation from the crystallographic theory. The instability criteria for all the phase transformations have been derived for all the kinematic models, and their comparative study is presented. A large strain finite element procedure has been developed and used for studying the evolution of some complex microstructures in nanoscale samples under various loading conditions. Also, the stresses within variant-variant boundaries, the sample size effect, effect of penalizing the triple junctions, and twinned microstructures have been studied. The present approach can be extended for studying grain growth, solidifications, para↔ferro electric transformations, and diffusive phase transformations.

NEUROPSYCHOLOGICAL-DEVELOPMENT APPROACH IN AUTISTIC CHILDREN

Directory of Open Access Journals (Sweden)

Dragoslav KOPACHEV

2005-06-01

Full Text Available This paper on the children’s autism gives an overview of neuropsychological aspect and in context of the development dynamic approach.The author expresses some characteristics and dilemmas which refer to the Kanner’s autism and Asperger`s syndrome. He presents his own opinion and dilemmas about the every day practice in relation to children’s autism as a pathological disorder which is an expression of pervasive disorder, children’s psychosis or just one development phase in which children are fixated forever.The author thinks children’s autism should be seen in context of the inter-game of biological factors, development and the stress.

Nonlinear approaches for phase retrieval in the Fresnel region for hard X-ray imaging

International Nuclear Information System (INIS)

Davidoiu, Valentina

2013-01-01

The development of highly coherent X-ray sources offers new possibilities to image biological structures at different scales exploiting the refraction of X-rays. The coherence properties of the third-generation synchrotron radiation sources enables efficient implementations of phase contrast techniques. One of the first measurements of the intensity variations due to phase contrast has been reported in 1995 at the European Synchrotron Radiation Facility (ESRF). Phase imaging coupled to tomography acquisition allows three dimensional imaging with an increased sensitivity compared to absorption CT. This technique is particularly attractive to image samples with low absorption constituents. Phase contrast has many applications, ranging from material science, paleontology, bone research to medicine and biology. Several methods to achieve X-ray phase contrast have been proposed during the last years. In propagation based phase contrast, the measurements are made at different sample-to-detector distances. While the intensity data can be acquired and recorded, the phase information of the signal has to be 'retrieved' from the modulus data only. Phase retrieval is thus an ill-posed nonlinear problem and regularization techniques including a priori knowledge are necessary to obtain stable solutions. Several phase recovery methods have been developed in recent years. These approaches generally formulate the phase retrieval problem as a linear one. Nonlinear treatments have not been much investigated. The main purpose of this work was to propose and evaluate new algorithms, in particularly taking into account the nonlinearity of the direct problem. In the first part of this work, we present a Landweber type nonlinear iterative scheme to solve the propagation based phase retrieval problem. This approach uses the analytic expression of the Frechet derivative of the phase-intensity relationship and of its adjoint, which are presented in detail. We also study the effect of

Designing eHealth that Matters via a Multidisciplinary Requirements Development Approach.

Science.gov (United States)

Van Velsen, Lex; Wentzel, Jobke; Van Gemert-Pijnen, Julia Ewc

2013-06-24

Requirements development is a crucial part of eHealth design. It entails all the activities devoted to requirements identification, the communication of requirements to other developers, and their evaluation. Currently, a requirements development approach geared towards the specifics of the eHealth domain is lacking. This is likely to result in a mismatch between the developed technology and end user characteristics, physical surroundings, and the organizational context of use. It also makes it hard to judge the quality of eHealth design, since it makes it difficult to gear evaluations of eHealth to the main goals it is supposed to serve. In order to facilitate the creation of eHealth that matters, we present a practical, multidisciplinary requirements development approach which is embedded in a holistic design approach for eHealth (the Center for eHealth Research roadmap) that incorporates both human-centered design and business modeling. Our requirements development approach consists of five phases. In the first, preparatory, phase the project team is composed and the overall goal(s) of the eHealth intervention are decided upon. Second, primary end users and other stakeholders are identified by means of audience segmentation techniques and our stakeholder identification method. Third, the designated context of use is mapped and end users are profiled by means of requirements elicitation methods (eg, interviews, focus groups, or observations). Fourth, stakeholder values and eHealth intervention requirements are distilled from data transcripts, which leads to phase five, in which requirements are communicated to other developers using a requirements notation template we developed specifically for the context of eHealth technologies. The end result of our requirements development approach for eHealth interventions is a design document which includes functional and non-functional requirements, a list of stakeholder values, and end user profiles in the form of

Development of whole-building energy design targets for commercial buildings: Phase 1, Planning: Volume 2, Technical report

Energy Technology Data Exchange (ETDEWEB)

Crawley, D.B.; Briggs, R.S.; Jones, J.W.; Seaton, W.W.; Kaufman, J.E.; Deringer, J.J.; Kennett, E.W.

1987-08-01

This is the second volume of the Phase 1 report and discusses the 10 tasks performed in Phase 1. The objective of this research is to develop a methodology for setting energy design targets to provide voluntary guidelines for the buildings industry. The whole-building energy targets project is being conducted at the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) to encourage the construction of energy-efficient buildings by informing designers and owners about cost-effective goals for energy use in new commercial buildings. The outcome of this research will be a flexible methodology for setting such targets. The tasks are listed and discussed in this report as follows: Task 1 - Develop Detailed Project Goals and Objectives; Task 2 - Establish Buildings-Industry Liaison; Task 3 - Develop Approaches to the Energy Targets Model, Building Operations, and Climate; Task 4 - Develop an Approach for Treating Economic Considerations; Task 5 - Develop an Approach for Treating Energy Sources; Task 6 - Collect Energy-Use Data; Task 7 - Survey Energy Expert Opinion; Task 8 - Evaluation Procedure Specification and Integration; Task 9 - Phase 1 Report Development; and Task 10 - Phase 1 Review Planning.

Developing a univariate approach to phase-I monitoring of fuzzy quality profiles

Directory of Open Access Journals (Sweden)

Kazem Noghondarian

2012-10-01

Full Text Available In many real-world applications, the quality of a process or a particular product can be characterized by a functional relationship called profile. A profile builds the relationships between a response quality characteristic and one or more explanatory variables. Monitoring the quality of a profile is implemented to understand and to verify the stability of this functional relationship over time. In some real applications, a fuzzy linear regression model can represent the profile adequately where the response quality characteristic is fuzzy. The purpose of this paper is to develop an approach for monitoring process/product profiles in fuzzy environment. A model in fuzzy linear regression is developed to construct the quality profiles by using linear programming and then fuzzy individuals and moving-range (I-MR control charts are developed to monitor both intercept and slope of fuzzy profiles to achieve an in-control process. A case study in customer satisfaction is presented to show the application of our approach and to express the sensitivity analysis of parameters for building a fuzzy profile.

Conducting Research with young people and developing the MTW Approach

DEFF Research Database (Denmark)

Frostholm, Peter Hornbæk; Mikkelsen, Sidse Hølvig; Gravesen, David Thore

2017-01-01

Abstract In this article we present our qualitative mixed-methods methodology that we name the Map-Talk-Walk Approach (MTW Approach). We developed the approach to better grasp young people’s understandings of youth, normality and belonging, which make up the thematic framework of our current youth...... research. The MTW Approach is based on three phases, 1) Researcher-initiated workshops, 2) Focus group interviews, and 3) Walk-and-talks in the young people’s local environments. In the article, we discuss the ethical complications related to doing research with young people and positioning them as experts...... in their life worlds. Our ambition is to create a democratized research process that allows the participants ownership, and we find this to be a challenging task. In the closing section, after a thorough presentation of the three phases, we discuss some of the pitfalls we experienced during the process...

A simplified approach for the computation of steady two-phase flow in inverted siphons.

Science.gov (United States)

Diogo, A Freire; Oliveira, Maria C

2016-01-15

Hydraulic, sanitary, and sulfide control conditions of inverted siphons, particularly in large wastewater systems, can be substantially improved by continuous air injection in the base of the inclined rising branch. This paper presents a simplified approach that was developed for the two-phase flow of the rising branch using the energy equation for a steady pipe flow, based on the average fluid fraction, observed slippage between phases, and isothermal assumption. As in a conventional siphon design, open channel steady uniform flow is assumed in inlet and outlet chambers, corresponding to the wastewater hydraulic characteristics in the upstream and downstream sewers, and the descending branch operates in steady uniform single-phase pipe flow. The proposed approach is tested and compared with data obtained in an experimental siphon setup with two plastic barrels of different diameters operating separately as in a single-barrel siphon. Although the formulations developed are very simple, the results show a good adjustment for the set of the parameters used and conditions tested and are promising mainly for sanitary siphons with relatively moderate heights of the ascending branch. Copyright © 2015 Elsevier Ltd. All rights reserved.

3D measurement using combined Gray code and dual-frequency phase-shifting approach

Science.gov (United States)

Yu, Shuang; Zhang, Jing; Yu, Xiaoyang; Sun, Xiaoming; Wu, Haibin; Liu, Xin

2018-04-01

The combined Gray code and phase-shifting approach is a commonly used 3D measurement technique. In this technique, an error that equals integer multiples of the phase-shifted fringe period, i.e. period jump error, often exists in the absolute analog code, which can lead to gross measurement errors. To overcome this problem, the present paper proposes 3D measurement using a combined Gray code and dual-frequency phase-shifting approach. Based on 3D measurement using the combined Gray code and phase-shifting approach, one set of low-frequency phase-shifted fringe patterns with an odd-numbered multiple of the original phase-shifted fringe period is added. Thus, the absolute analog code measured value can be obtained by the combined Gray code and phase-shifting approach, and the low-frequency absolute analog code measured value can also be obtained by adding low-frequency phase-shifted fringe patterns. Then, the corrected absolute analog code measured value can be obtained by correcting the former by the latter, and the period jump errors can be eliminated, resulting in reliable analog code unwrapping. For the proposed approach, we established its measurement model, analyzed its measurement principle, expounded the mechanism of eliminating period jump errors by error analysis, and determined its applicable conditions. Theoretical analysis and experimental results show that the proposed approach can effectively eliminate period jump errors, reliably perform analog code unwrapping, and improve the measurement accuracy.

Emergency Preparedness. HERCA-Approach for a better cross-border coordination of protective actions during the response in the early phase of a nuclear accident; development and practical testing

International Nuclear Information System (INIS)

Aaltonen, Hannele; Kuusi, Antero; Bijlholt, Jette; Calvaro, Jose-Manuel Martin; Mozas Garcia, Alfredo; Constantinou, Costas; Janssens, Augustin; ); Degueldre, Didier; Vandecasteele, Christian; Willems, Petra; Djounova, Jana; Fueloep, Nandor; Gering, Florian; Lieser, Joachim; Halldorsson, Oskar; Haywood, Stephanie; Hofer, Peter; Holo, Eldri; Hubbard, Lynn; Lindh, Karin; Isnard, Olivier; Kuhlen, Johannes; Rother, Wolfram; Lachaume, Jean-Luc; Perrin, Marie-Line; Xicluna, Delphine; Majerus, Patrick; McMahon, Ciara; Murith, Christophe; Nizamska, Marina; Rauber, Dominique; Rusch, Ronald; Stahl, Thorsten; Stephen, Patrick; Tkavc, Marjan; Van Gelder, Iris

2014-06-01

The HERCA-Approach on emergencies relies on the following principles: mutual understanding, coordination and mutual trust. It does not aim at proposing a uniform cross border framework to deal with such situations. The main strategy is to aim at an alignment of the response between neighbouring countries, or neighbouring territories. The HERCA-Approach comprises mechanisms of early information exchanges allowing neighbouring countries to align measures for protective actions by using as far as possible the existing dedicated bilateral and international arrangements. The HERCA-Approach is divided into 3 steps, the preparedness phase, the early phase and the later phase (development of a common situation report). The approach contains the main principles and leaves necessary margins of freedom for detailed implementation: - In preparedness the aim is to achieve and maintain a shared understanding of the existing national emergency arrangements through the improvement of bilateral or multilateral arrangements, the testing of these arrangements and the implementation of improvements. - In the early phase of an accident, the proposed HERCA-Approach foresees rapid information exchanges by using as far as possible the existing dedicated bilateral and international arrangements, including the exchange of liaison officers as appropriate. If the response is thought consistent, the neighbouring countries can recommend to their governments to follow these recommendations, i.e. adopt the principle that in the first hours, 'we do the same as the accident country'. - In the later phase a common situation report, accepted by all impacted countries, will further support coordinated protective actions. The HERCA-Approach has been tested and validated against concrete and realistic accident scenarios in NPPs that are close enough to national borders. Therefore a workshop was organized in September 2013. The workshop showed that in case of a sufficient information exchange most

Stochastic modelling of two-phase flows including phase change

International Nuclear Information System (INIS)

Hurisse, O.; Minier, J.P.

2011-01-01

Stochastic modelling has already been developed and applied for single-phase flows and incompressible two-phase flows. In this article, we propose an extension of this modelling approach to two-phase flows including phase change (e.g. for steam-water flows). Two aspects are emphasised: a stochastic model accounting for phase transition and a modelling constraint which arises from volume conservation. To illustrate the whole approach, some remarks are eventually proposed for two-fluid models. (authors)

Are separate-phase thermal-hydraulic models better than mixture-fluid approaches? It depends. Rather not

International Nuclear Information System (INIS)

Hoeld, A.

2004-01-01

constants) be easily provided by corresponding time-delays of 1 st order. The problem of the mixture-fluid models lies in the difficult question how to discretize and solve the basic eqs. in view of possible phase discontinuities due to varying boiling or superheating boundaries. To circumvent these problems a special procedure has been developed ('separate-region' mixture-fluid approach), subdividing a coolant channel (called 'basic channel' BC) according to different flow regimes into their corresponding regions (called sub-channels SC-s), thereby being aware of possible time-varying entrance and outlet boundaries. Based on this theoretical approach an effective and time-efficient TH coolant channel module (CCM) has been established including within a unique formulation all the limit cases such as the smooth transition from steady state to transient situations, from singleto two-phase flow (thereby determining automatically their varying boundaries), flashing and condensation etc., effects which demand in a separate-phase approach special models. (author)

Comparison of phase-constrained parallel MRI approaches: Analogies and differences.

Science.gov (United States)

Blaimer, Martin; Heim, Marius; Neumann, Daniel; Jakob, Peter M; Kannengiesser, Stephan; Breuer, Felix A

2016-03-01

Phase-constrained parallel MRI approaches have the potential for significantly improving the image quality of accelerated MRI scans. The purpose of this study was to investigate the properties of two different phase-constrained parallel MRI formulations, namely the standard phase-constrained approach and the virtual conjugate coil (VCC) concept utilizing conjugate k-space symmetry. Both formulations were combined with image-domain algorithms (SENSE) and a mathematical analysis was performed. Furthermore, the VCC concept was combined with k-space algorithms (GRAPPA and ESPIRiT) for image reconstruction. In vivo experiments were conducted to illustrate analogies and differences between the individual methods. Furthermore, a simple method of improving the signal-to-noise ratio by modifying the sampling scheme was implemented. For SENSE, the VCC concept was mathematically equivalent to the standard phase-constrained formulation and therefore yielded identical results. In conjunction with k-space algorithms, the VCC concept provided more robust results when only a limited amount of calibration data were available. Additionally, VCC-GRAPPA reconstructed images provided spatial phase information with full resolution. Although both phase-constrained parallel MRI formulations are very similar conceptually, there exist important differences between image-domain and k-space domain reconstructions regarding the calibration robustness and the availability of high-resolution phase information. © 2015 Wiley Periodicals, Inc.

Housing decision making methods for initiation development phase process

Science.gov (United States)

Zainal, Rozlin; Kasim, Narimah; Sarpin, Norliana; Wee, Seow Ta; Shamsudin, Zarina

2017-10-01

Late delivery and sick housing project problems were attributed to poor decision making. These problems are the string of housing developer that prefers to create their own approach based on their experiences and expertise with the simplest approach by just applying the obtainable standards and rules in decision making. This paper seeks to identify the decision making methods for housing development at the initiation phase in Malaysia. The research involved Delphi method by using questionnaire survey which involved 50 numbers of developers as samples for the primary stage of collect data. However, only 34 developers contributed to the second stage of the information gathering process. At the last stage, only 12 developers were left for the final data collection process. Finding affirms that Malaysian developers prefer to make their investment decisions based on simple interpolation of historical data and using simple statistical or mathematical techniques in producing the required reports. It was suggested that they seemed to skip several important decision-making functions at the primary development stage. These shortcomings were mainly due to time and financial constraints and the lack of statistical or mathematical expertise among the professional and management groups in the developer organisations.

Phase Imaging: A Compressive Sensing Approach

Energy Technology Data Exchange (ETDEWEB)

Schneider, Sebastian; Stevens, Andrew; Browning, Nigel D.; Pohl, Darius; Nielsch, Kornelius; Rellinghaus, Bernd

2017-07-01

Since Wolfgang Pauli posed the question in 1933, whether the probability densities |Ψ(r)|² (real-space image) and |Ψ(q)|² (reciprocal space image) uniquely determine the wave function Ψ(r) [1], the so called Pauli Problem sparked numerous methods in all fields of microscopy [2, 3]. Reconstructing the complete wave function Ψ(r) = a(r)e-iφ(r) with the amplitude a(r) and the phase φ(r) from the recorded intensity enables the possibility to directly study the electric and magnetic properties of the sample through the phase. In transmission electron microscopy (TEM), electron holography is by far the most established method for phase reconstruction [4]. Requiring a high stability of the microscope, next to the installation of a biprism in the TEM, holography cannot be applied to any microscope straightforwardly. Recently, a phase retrieval approach was proposed using conventional TEM electron diffractive imaging (EDI). Using the SAD aperture as reciprocal-space constraint, a localized sample structure can be reconstructed from its diffraction pattern and a real-space image using the hybrid input-output algorithm [5]. We present an alternative approach using compressive phase-retrieval [6]. Our approach does not require a real-space image. Instead, random complimentary pairs of checkerboard masks are cut into a 200 nm Pt foil covering a conventional TEM aperture (cf. Figure 1). Used as SAD aperture, subsequently diffraction patterns are recorded from the same sample area. Hereby every mask blocks different parts of gold particles on a carbon support (cf. Figure 2). The compressive sensing problem has the following formulation. First, we note that the complex-valued reciprocal-space wave-function is the Fourier transform of the (also complex-valued) real-space wave-function, Ψ(q) = F[Ψ(r)], and subsequently the diffraction pattern image is given by |Ψ(q)|2 = |F[Ψ(r)]|2. We want to find Ψ(r) given a few differently coded diffraction pattern measurements yn

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

Science.gov (United States)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

1984-01-01

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

Science.gov (United States)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399

Recent development of ionic liquid stationary phases for liquid chromatography.

Science.gov (United States)

Shi, Xianzhe; Qiao, Lizhen; Xu, Guowang

2015-11-13

Based on their particular physicochemical characteristics, ionic liquids have been widely applied in many fields of analytical chemistry. Many types of ionic liquids were immobilized on a support like silica or monolith as stationary phases for liquid chromatography. Moreover, different approaches were developed to bond covalently ionic liquids onto the supporting materials. The obtained ionic liquid stationary phases show multi-mode mechanism including hydrophobic, hydrophilic, hydrogen bond, anion exchange, π-π, and dipole-dipole interactions. Therefore, they could be used in different chromatographic modes including ion-exchange, RPLC, NPLC and HILIC to separate various classes of compounds. This review mainly summarizes the immobilized patterns and types of ionic liquid stationary phases, their retention mechanisms and applications in the recent five years. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of phased-array ultrasonic testing probe

International Nuclear Information System (INIS)

Kawanami, Seiichi; Kurokawa, Masaaki; Taniguchi, Masaru; Tada, Yoshihisa

2001-01-01

Phased-array ultrasonic testing was developed for nondestructive evaluation of power plants. Phased-array UT scans and focuses an ultrasonic beam to inspect areas difficult to inspect by conventional UT. We developed a highly sensitive piezoelectric composite, and designed optimized phased-array UT probes. We are applying our phased-array UT to different areas of power plants. (author)

DE-FOA-EE0005502 Advanced Percussive Drilling Technology for Geothermal Exploration and Development Phase II Report.

Energy Technology Data Exchange (ETDEWEB)

Su, Jiann-Cherng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Raymond, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Prasad, Somuri V. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wolfer, Dale R. [Atlas-Copco Secoroc, LLC, Fagersta (Sweden)

2017-05-01

Percussive hammers are a promising advance in drilling technology for geothermal since they rely upon rock reduction mechanisms that are well-suited for use in the hard, brittle rock characteristic of geothermal formations. The project research approach and work plan includes a critical path to development of a high-temperature (HT) percussive hammer using a two- phase approach. The work completed in Phase I of the project demonstrated the viability of percussive hammers and that solutions to technical challenges in design, material technology, and performance are likely to be resolved. Work completed in Phase II focused on testing the findings from Phase I and evaluating performance of the materials and designs at high- operating temperatures. A high-operating temperature (HOT) drilling facility was designed, built, and used to test the performance of the DTH under extreme conditions. Results from the testing indicate that a high-temperature capable hammer can be developed and is a viable alternative for user in the driller's toolbox.

A mathematical model for maximizing the value of phase 3 drug development portfolios incorporating budget constraints and risk.

Science.gov (United States)

Patel, Nitin R; Ankolekar, Suresh; Antonijevic, Zoran; Rajicic, Natasa

2013-05-10

We describe a value-driven approach to optimizing pharmaceutical portfolios. Our approach incorporates inputs from research and development and commercial functions by simultaneously addressing internal and external factors. This approach differentiates itself from current practices in that it recognizes the impact of study design parameters, sample size in particular, on the portfolio value. We develop an integer programming (IP) model as the basis for Bayesian decision analysis to optimize phase 3 development portfolios using expected net present value as the criterion. We show how this framework can be used to determine optimal sample sizes and trial schedules to maximize the value of a portfolio under budget constraints. We then illustrate the remarkable flexibility of the IP model to answer a variety of 'what-if' questions that reflect situations that arise in practice. We extend the IP model to a stochastic IP model to incorporate uncertainty in the availability of drugs from earlier development phases for phase 3 development in the future. We show how to use stochastic IP to re-optimize the portfolio development strategy over time as new information accumulates and budget changes occur. Copyright © 2013 John Wiley & Sons, Ltd.

A Phase Current Reconstruction Approach for Three-Phase Permanent-Magnet Synchronous Motor Drive

Directory of Open Access Journals (Sweden)

Hao Yan

2016-10-01

Full Text Available Three-phase permanent-magnet synchronous motors (PMSMs are widely used in renewable energy applications such as wind power generation, tidal energy and electric vehicles owing to their merits such as high efficiency, high precision and high reliability. To reduce the cost and volume of the drive system, techniques of reconstructing three-phase current using a single current sensor have been reported for three-phase alternating current (AC control system using the power converts. In existing studies, the reconstruction precision is largely influenced by reconstructing dead zones on the Space Vector Pulse Width Modulation (SVPWM plane, which requires other algorithms to compensate either by modifying PWM modulation or by phase-shifting of the PWM signal. In this paper, a novel extended phase current reconstruction approach for PMSM drive is proposed. Six novel installation positions are obtained by analyzing the sampling results of the current paths between each two power switches. By arranging the single current sensor at these positions, the single current sensor is sampled during zero voltage vectors (ZVV without modifying the PWM signals. This proposed method can reconstruct the three-phase currents without any complex algorithms and is available in the sector boundary region and low modulation region. Finally, this method is validated by experiments.

CONCEPTUAL ANALYSIS OF THE CURRENT PHASE DEVELOPMENT OF RELATIONS BETWEEN RUSSIA AND ISRAEL

Directory of Open Access Journals (Sweden)

Yuri B. Bocharov

2013-01-01

Full Text Available The article dedicated to analysis of Russian-Israeli international business relations by using of all the arsenal of modern methods. The article investigates the possibility of using the geo-political, geo-economic and geo-cultural approaches to definition of optimal ways of relations between the two countries' development. It demonstrates that due to the historical and cultural features of the nature of relations between those two countries, geo-cultural approach is more preferable. Also, the article shows that this approach of the analysis is not often used for the analysis of relations of Russia with other countries. The geo-cultural approach of analysis had used for elaboration of suggestions of new phase of development of business relations between Russia and Israel.

Community-led local development approach principles implementation when forming a regional local development projects support system in Ukraine

Directory of Open Access Journals (Sweden)

Y. G. Udod

2017-03-01

Full Text Available The article contains a brief description of the Community-led local development approach (local development under the leadership of the community, CLLD and the main purpose of its use in the European Union. The study indicated periods of the major initiatives to support local development in EU. Moreover the article posted CLLD approach principles’ evolution and the basic principles of the LEADER method and its application in CLLD, which can be applied in Ukraine. Subject to the provisions of the European Economic and Social Committee (EESC for further CLLD-approach distribution the five trends were identified that must be considered when forming a Regional local development projects support system in Ukraine: Multi-fund financing; Unification; Networking and collaboration; Extending the approach; Simplifying the process. The characteristic of the present phase of CLLD-approach, in particular, of the European Network for Rural Development (ENRD, which attaches great importance to the dissemination of the most effective CLLD practices and establish partnerships between communities and territories where the approach is implemented. The study found out the relationship between Community-led local development and Community-driven development (CDD supported by the World Bank.

Hybridization approach to in-line and off-axis (electron) holography for superior resolution and phase sensitivity

Science.gov (United States)

Ozsoy-Keskinbora, C.; Boothroyd, C. B.; Dunin-Borkowski, R. E.; van Aken, P. A.; Koch, C. T.

2014-01-01

Holography - originally developed for correcting spherical aberration in transmission electron microscopes - is now used in a wide range of disciplines that involve the propagation of waves, including light optics, electron microscopy, acoustics and seismology. In electron microscopy, the two primary modes of holography are Gabor's original in-line setup and an off-axis approach that was developed subsequently. These two techniques are highly complementary, offering superior phase sensitivity at high and low spatial resolution, respectively. All previous investigations have focused on improving each method individually. Here, we show how the two approaches can be combined in a synergetic fashion to provide phase information with excellent sensitivity across all spatial frequencies, low noise and an efficient use of electron dose. The principle is also expected to be widely to applications of holography in light optics, X-ray optics, acoustics, ultra-sound, terahertz imaging, etc. PMID:25387480

Phase diagram of two-color QCD in a Dyson-Schwinger approach

Energy Technology Data Exchange (ETDEWEB)

Buescher, Pascal Joachim

2014-04-28

We investigate two-color QCD with N{sub f}=2 at finite temperatures and chemical potentials using a Dyson-Schwinger approach. We employ two different truncations for the quark loop in the gluon DSE: one based on the Hard-Dense/Hard-Thermal Loop (HDTL) approximation of the quark loop and one based on the back-coupling of the full, self-consistent quark propagator (SCQL). We compare results for the different truncations with each other as well as with other approaches. As expected, we find a phase dominated by the condensation of quark-quark pairs. This diquark condensation phase overshadows the critical end point and first-order phase transition which one finds if diquark condensation is neglected. The phase transition from the phase without diquark condensation to the diquark-condensation phase is of second order. We observe that the dressing with massless quarks in the HDTL approximation leads to a significant violation of the Silver Blaze property and to a too small diquark condensate. The SCQL truncation, on the other hand, is found to reproduce all expected features of the μ-dependent quark condensates. Moreover, with parameters adapted to the situation in other approaches, we also find good to very good agreement with model and lattice calculations in all quark quantities. We find indictions that the physics in recent lattice calculations is likely to be driven solely by the explicit chiral symmetry breaking. Discrepancies w.r.t. the lattice are, however, observed in two quantities that are very sensitive to the screening of the gluon propagator, the dressed gluon propagator itself and the phase-transition line at high temperatures.

Quantum renormalization group approach to geometric phases in spin chains

International Nuclear Information System (INIS)

Jafari, R.

2013-01-01

A relation between geometric phases and criticality of spin chains are studied using the quantum renormalization-group approach. I have shown how the geometric phase evolve as the size of the system becomes large, i.e., the finite size scaling is obtained. The renormalization scheme demonstrates how the first derivative of the geometric phase with respect to the field strength diverges at the critical point and maximum value of the first derivative, and its position, scales with the exponent of the system size

A level set approach for shock-induced α-γ phase transition of RDX

Science.gov (United States)

Josyula, Kartik; Rahul; De, Suvranu

2018-02-01

We present a thermodynamically consistent level sets approach based on regularization energy functional which can be directly incorporated into a Galerkin finite element framework to model interface motion. The regularization energy leads to a diffusive form of flux that is embedded within the level sets evolution equation which maintains the signed distance property of the level set function. The scheme is shown to compare well with the velocity extension method in capturing the interface position. The proposed level sets approach is employed to study the α-γphase transformation in RDX single crystal shocked along the (100) plane. Example problems in one and three dimensions are presented. We observe smooth evolution of the phase interface along the shock direction in both models. There is no diffusion of the interface during the zero level set evolution in the three dimensional model. The level sets approach is shown to capture the characteristics of the shock-induced α-γ phase transformation such as stress relaxation behind the phase interface and the finite time required for the phase transformation to complete. The regularization energy based level sets approach is efficient, robust, and easy to implement.

Beam splitter phase shifts: Wave optics approach

Science.gov (United States)

Agnesi, Antonio; Degiorgio, Vittorio

2017-10-01

We investigate the phase relationships between transmitted and reflected waves in a lossless beam splitter having a multilayer structure, using the matrix approach as outlined in classical optics books. Contrarily to the case of the quantum optics formalism generally employed to describe beam splitters, these matrices are not unitary. In this note we point out the existence of general relations among the elements of the transfer matrix that describes the multilayer beam splitter. Such relations, which are independent of the detailed structure of the beam splitter, fix the phase shifts between reflected and transmitted waves. It is instructive to see how the results obtained by Zeilinger by using spinor algebra and Pauli matrices can be easily derived from our general relations.

Effect of primary and secondary parameters on analytical estimation of effective thermal conductivity of two phase materials using unit cell approach

Science.gov (United States)

S, Chidambara Raja; P, Karthikeyan; Kumaraswamidhas, L. A.; M, Ramu

2018-05-01

Most of the thermal design systems involve two phase materials and analysis of such systems requires detailed understanding of the thermal characteristics of the two phase material. This article aimed to develop geometry dependent unit cell approach model by considering the effects of all primary parameters (conductivity ratio and concentration) and secondary parameters (geometry, contact resistance, natural convection, Knudsen and radiation) for the estimation of effective thermal conductivity of two-phase materials. The analytical equations have been formulated based on isotherm approach for 2-D and 3-D spatially periodic medium. The developed models are validated with standard models and suited for all kind of operating conditions. The results have shown substantial improvement compared to the existing models and are in good agreement with the experimental data.

Hole-expansion formability of dual-phase steels using representative volume element approach with boundary-smoothing technique

International Nuclear Information System (INIS)

Kim, Ji Hoon; Lee, M.G.; Kim, D.; Matlock, D.K.; Wagoner, R.H.

2010-01-01

Research highlights: → Robust microstructure-based FE mesh generation technique was developed. → Local deformation behavior near phase boundaries could be quantitatively understood. → Macroscopic failure could be connected to microscopic deformation behavior of multi-phase steel. - Abstract: A qualitative analysis was carried out on the formability of dual-phase (DP) steels by introducing a realistic microstructure-based finite element approach. The present microstructure-based model was constructed using a mesh generation process with a boundary-smoothing algorithm after proper image processing. The developed model was applied to hole-expansion formability tests for DP steel sheets having different volume fractions and morphological features. On the basis of the microstructural inhomogeneity observed in the scanning electron micrographs of the DP steel sheets, it was inferred that the localized plastic deformation in the ferritic phase might be closely related to the macroscopic formability of DP steel. The experimentally observed difference between the hole-expansion formability of two different microstructures was reasonably explained by using the present finite element model.

CrowdPhase: crowdsourcing the phase problem

International Nuclear Information System (INIS)

Jorda, Julien; Sawaya, Michael R.; Yeates, Todd O.

2014-01-01

The idea of attacking the phase problem by crowdsourcing is introduced. Using an interactive, multi-player, web-based system, participants work simultaneously to select phase sets that correspond to better electron-density maps in order to solve low-resolution phasing problems. The human mind innately excels at some complex tasks that are difficult to solve using computers alone. For complex problems amenable to parallelization, strategies can be developed to exploit human intelligence in a collective form: such approaches are sometimes referred to as ‘crowdsourcing’. Here, a first attempt at a crowdsourced approach for low-resolution ab initio phasing in macromolecular crystallography is proposed. A collaborative online game named CrowdPhase was designed, which relies on a human-powered genetic algorithm, where players control the selection mechanism during the evolutionary process. The algorithm starts from a population of ‘individuals’, each with a random genetic makeup, in this case a map prepared from a random set of phases, and tries to cause the population to evolve towards individuals with better phases based on Darwinian survival of the fittest. Players apply their pattern-recognition capabilities to evaluate the electron-density maps generated from these sets of phases and to select the fittest individuals. A user-friendly interface, a training stage and a competitive scoring system foster a network of well trained players who can guide the genetic algorithm towards better solutions from generation to generation via gameplay. CrowdPhase was applied to two synthetic low-resolution phasing puzzles and it was shown that players could successfully obtain phase sets in the 30° phase error range and corresponding molecular envelopes showing agreement with the low-resolution models. The successful preliminary studies suggest that with further development the crowdsourcing approach could fill a gap in current crystallographic methods by making it

CrowdPhase: crowdsourcing the phase problem

Energy Technology Data Exchange (ETDEWEB)

Jorda, Julien; Sawaya, Michael R. [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Yeates, Todd O., E-mail: yeates@mbi.ucla.edu [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Molecular Biology Institute, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); University of California, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States)

2014-06-01

The idea of attacking the phase problem by crowdsourcing is introduced. Using an interactive, multi-player, web-based system, participants work simultaneously to select phase sets that correspond to better electron-density maps in order to solve low-resolution phasing problems. The human mind innately excels at some complex tasks that are difficult to solve using computers alone. For complex problems amenable to parallelization, strategies can be developed to exploit human intelligence in a collective form: such approaches are sometimes referred to as ‘crowdsourcing’. Here, a first attempt at a crowdsourced approach for low-resolution ab initio phasing in macromolecular crystallography is proposed. A collaborative online game named CrowdPhase was designed, which relies on a human-powered genetic algorithm, where players control the selection mechanism during the evolutionary process. The algorithm starts from a population of ‘individuals’, each with a random genetic makeup, in this case a map prepared from a random set of phases, and tries to cause the population to evolve towards individuals with better phases based on Darwinian survival of the fittest. Players apply their pattern-recognition capabilities to evaluate the electron-density maps generated from these sets of phases and to select the fittest individuals. A user-friendly interface, a training stage and a competitive scoring system foster a network of well trained players who can guide the genetic algorithm towards better solutions from generation to generation via gameplay. CrowdPhase was applied to two synthetic low-resolution phasing puzzles and it was shown that players could successfully obtain phase sets in the 30° phase error range and corresponding molecular envelopes showing agreement with the low-resolution models. The successful preliminary studies suggest that with further development the crowdsourcing approach could fill a gap in current crystallographic methods by making it

Phase II clinical development of new drugs

CERN Document Server

Ting, Naitee; Ho, Shuyen; Cappelleri, Joseph C

2017-01-01

This book focuses on how to appropriately plan and develop a Phase II program, and how to design Phase II clinical trials and analyze their data. It provides a comprehensive overview of the entire drug development process and highlights key questions that need to be addressed for the successful execution of Phase II, so as to increase its success in Phase III and for drug approval. Lastly it warns project team members of the common potential pitfalls and offers tips on how to avoid them.

Comparison of propagation-based phase-contrast tomography approaches for the evaluation of dentin microstructure

Science.gov (United States)

Deyhle, Hans; Weitkamp, Timm; Lang, Sabrina; Schulz, Georg; Rack, Alexander; Zanette, Irene; Müller, Bert

2012-10-01

The complex hierarchical structure of human tooth hard tissues, enamel and dentin, guarantees function for decades. On the micrometer level the dentin morphology is dominated by the tubules, micrometer-narrow channels extending from the dentin-enamel junction to the pulp chamber. Their structure has been extensively studied, mainly with two-dimensional approaches. Dentin tubules are formed during tooth growth and their orientation is linked to the morphology of the nanometer-sized components, which is of interest for example for the development of bio-inspired dental fillings. Therefore, a method has to be identified that can access the three-dimensional organization of the tubules, e.g. density and orientation. Tomographic setups with pixel sizes in the sub-micrometer range allow for the three-dimensional visualization of tooth dentin tubules both in phase and absorption contrast modes. We compare high-resolution tomographic scans reconstructed with propagation based phase retrieval algorithms as well as reconstructions without phase retrieval concerning spatial and density resolution as well as rendering of the dentin microstructure to determine the approach best suited for dentin tubule imaging. Reasonable results were obtained with a single-distance phase retrieval algorithm and a propagation distance of about 75% of the critical distance of d2/λ, where d is the size of the smallest objects identifiable in the specimen and λ is the X-ray wavelength.

Science based integrated approach to advanced nuclear fuel development - vision, approach, and overview

Energy Technology Data Exchange (ETDEWEB)

Unal, Cetin [Los Alamos National Laboratory; Pasamehmetoglu, Kemal [IDAHO NATIONAL LAB; Carmack, Jon [IDAHO NATIONAL LAB

2010-01-01

Advancing the performance of Light Water Reactors, Advanced Nuclear Fuel Cycles, and Advanced Rcactors, such as the Next Generation Nuclear Power Plants, requires enhancing our fundamental understanding of fuel and materials behavior under irradiation. The capability to accurately model the nuclear fuel systems is critical. In order to understand specific aspects of the nuclear fuel, fully coupled fuel simulation codes are required to achieve licensing of specific nuclear fuel designs for operation. The backbone of these codes, models, and simulations is a fundamental understanding and predictive capability for simulating the phase and microstructural behavior of the nuclear fuel system materials and matrices. The purpose of this paper is to identify the modeling and simulation approach in order to deliver predictive tools for advanced fuels development. The coordination between experimental nuclear fuel design, development technical experts, and computational fuel modeling and simulation technical experts is a critical aspect of the approach and naturally leads to an integrated, goal-oriented science-based R & D approach and strengthens both the experimental and computational efforts. The Advanced Fuels Campaign (AFC) and Nuclear Energy Advanced Modeling and Simulation (NEAMS) Fuels Integrated Performance and Safety Code (IPSC) are working together to determine experimental data and modeling needs. The primary objective of the NEAMS fuels IPSC project is to deliver a coupled, three-dimensional, predictive computational platform for modeling the fabrication and both normal and abnormal operation of nuclear fuel pins and assemblies, applicable to both existing and future reactor fuel designs. The science based program is pursuing the development of an integrated multi-scale and multi-physics modeling and simulation platform for nuclear fuels. This overview paper discusses the vision, goals and approaches how to develop and implement the new approach.

Science based integrated approach to advanced nuclear fuel development - vision, approach, and overview

International Nuclear Information System (INIS)

Unal, Cetin; Pasamehmetoglu, Kemal; Carmack, Jon

2010-01-01

Advancing the performance of Light Water Reactors, Advanced Nuclear Fuel Cycles, and Advanced Rcactors, such as the Next Generation Nuclear Power Plants, requires enhancing our fundamental understanding of fuel and materials behavior under irradiation. The capability to accurately model the nuclear fuel systems is critical. In order to understand specific aspects of the nuclear fuel, fully coupled fuel simulation codes are required to achieve licensing of specific nuclear fuel designs for operation. The backbone of these codes, models, and simulations is a fundamental understanding and predictive capability for simulating the phase and microstructural behavior of the nuclear fuel system materials and matrices. The purpose of this paper is to identify the modeling and simulation approach in order to deliver predictive tools for advanced fuels development. The coordination between experimental nuclear fuel design, development technical experts, and computational fuel modeling and simulation technical experts is a critical aspect of the approach and naturally leads to an integrated, goal-oriented science-based R and D approach and strengthens both the experimental and computational efforts. The Advanced Fuels Campaign (AFC) and Nuclear Energy Advanced Modeling and Simulation (NEAMS) Fuels Integrated Performance and Safety Code (IPSC) are working together to determine experimental data and modeling needs. The primary objective of the NEAMS fuels IPSC project is to deliver a coupled, three-dimensional, predictive computational platform for modeling the fabrication and both normal and abnormal operation of nuclear fuel pins and assemblies, applicable to both existing and future reactor fuel designs. The science based program is pursuing the development of an integrated multi-scale and multi-physics modeling and simulation platform for nuclear fuels. This overview paper discusses the vision, goals and approaches how to develop and implement the new approach.

JREM: An Approach for Formalising Models in the Requirements Phase with JSON and NoSQL Databases

OpenAIRE

Aitana Alonso-Nogueira; Helia Estévez-Fernández; Isaías García

2017-01-01

This paper presents an approach to reduce some of its current flaws in the requirements phase inside the software development process. It takes the software requirements of an application, makes a conceptual modeling about it and formalizes it within JSON documents. This formal model is lodged in a NoSQL database which is document-oriented, that is, MongoDB, because of its advantages in flexibility and efficiency. In addition, this paper underlines the contributions of the detailed approach a...

An eigenstrain approach to predict phase transformation and self-accommodation in partially stabilized zirconia

International Nuclear Information System (INIS)

Hensl, Th.; Mühlich, U.; Budnitzki, M.; Kuna, M.

2015-01-01

Highlights: • Analytical model to predict phase transformation in PSZ is developed. • Analytical model to predict number of twins in monoclinic inclusions in PSZ. • Models consider inclusions size, shape, temperature, remote loading and surface energy. - Abstract: This work focuses on micromechanical modeling of the tetragonal to monoclinic phase transformation (t–m transformation) in partially stabilized zirconia (PSZ). Tetragonal particles dispersed in a cubic matrix may transform into the monoclinic phase under sufficiently high mechanical loading or if the material is cooled down below a critical temperature. This phase transformation is supposed to be responsible for the so called transformation toughening effect of PSZ. The transformation is usually accompanied by a self-accommodation process, which reduces the occurring eigenstresses in the surrounding matrix. The influences of particle size and geometry, chemical driving force, temperature, surface energy and remote loading on the t–m transformation are estimated by a thermostatic approach. We assume, that transformations occur, once the Gibbs free energy of the transformed equilibrium state is lower than that of the untransformed reference state. To obtain an analytical solution, the microstructure is modeled as an inclusion of rectangular cross section, restrained by an infinite elastic matrix, under plane strain conditions. The developed model for phase transformation captures the well-known size and temperature dependencies. Furthermore, it indicates a significant influence of the particle geometry, that large aspect ratios of the inclusion’s cross section lower the trigger stress for phase transformation

Spectral Cascade-Transport Turbulence Model Development for Two-Phase Flows

Science.gov (United States)

Brown, Cameron Scott

Turbulence modeling remains a challenging problem in nuclear reactor applications, particularly for the turbulent multiphase flow conditions in nuclear reactor subchannels. Understanding the fundamental physics of turbulent multiphase flows is crucial for the improvement and further development of multiphase flow models used in reactor operation and safety calculations. Reactor calculations with Reynolds-averaged Navier-Stokes (RANS) approach continue to become viable tools for reactor analysis. The on-going increase in available computational resources allows for turbulence models that are more complex than the traditional two-equation models to become practical choices for nuclear reactor computational fluid dynamic (CFD) and multiphase computational fluid dynamic (M-CFD) simulations. Similarly, increased computational capabilities continue to allow for higher Reynolds numbers and more complex geometries to be evaluated using direct numerical simulation (DNS), thus providing more validation and verification data for turbulence model development. Spectral turbulence models are a promising approach to M-CFD simulations. These models resolve mean flow parameters as well as the turbulent kinetic energy spectrum, reproducing more physical details of the turbulence than traditional two-equation type models. Previously, work performed by other researchers on a spectral cascade-transport model has shown that the model behaves well for single and bubbly twophase decay of isotropic turbulence, single and two-phase uniform shear flow, and single-phase flow in a channel without resolving the near-wall boundary layer for relatively low Reynolds number. Spectral models are great candidates for multiphase RANS modeling since bubble source terms can be modeled as contributions to specific turbulence scales. This work focuses on the improvement and further development of the spectral cascadetransport model (SCTM) to become a three-dimensional (3D) turbulence model for use in M

Quantum trajectory approach to the geometric phase: open bipartite systems

International Nuclear Information System (INIS)

Yi, X X; Liu, D P; Wang, W

2005-01-01

Through the quantum trajectory approach, we calculate the geometric phase acquired by a bipartite system subjected to decoherence. The subsystems that compose the bipartite system interact with each other and then are entangled in the evolution. The geometric phase due to the quantum jump for both the bipartite system and its subsystems is calculated and analysed. As an example, we present two coupled spin-1/2 particles to detail the calculations

Thematic Network on The role of Monitoring in a Phased Approach to Disposal - EUR 21025, 2004. Conclusions of the EC Thematic Network on The role of Monitoring in a Phased Approach to Geological Disposal of Radioactive Waste

International Nuclear Information System (INIS)

Barlow, Stephen

2005-01-01

within a phased approach to disposal will inform decisions about moving to the next phase, and will need to encompass wider societal considerations; (iv) monitoring post-closure may be implemented - it will be maintained for as long as society requires. The project also provided the following relevant reasons for monitoring: part of scientific investigation programme, safety demonstration, regulatory requirements, nuclear material safeguards, confirmation of key assumptions (in view of post closure safety) and confidence building. As conclusions the Thematic Network achieved the following main findings: - technology for monitoring already exists and is being implemented in various national programmes. Technologies do have limitations however and these need to be understood; - the monitoring activities will be different according to the phase reached within the phased disposal programme, and implementers should recognise that the monitoring objectives and techniques will change as they progress through the various phases; - monitoring activities should be implemented within the framework of a strategy developed to meet the needs of the national programme and societal expectations

Dependency Analysis Guidance Nordic/German Working Group on Common Cause Failure analysis. Phase 2, Development of Harmonized Approach and Applications for Common Cause Failure Quantification

Energy Technology Data Exchange (ETDEWEB)

Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi

2009-03-15

The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector

Dependency Analysis Guidance Nordic/German Working Group on Common Cause Failure analysis. Phase 2, Development of Harmonized Approach and Applications for Common Cause Failure Quantification

International Nuclear Information System (INIS)

Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi

2009-03-01

The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector

Quantitative Comparison of Ternary Eutectic Phase-Field Simulations with Analytical 3D Jackson-Hunt Approaches

Science.gov (United States)

Steinmetz, Philipp; Kellner, Michael; Hötzer, Johannes; Nestler, Britta

2018-02-01

For the analytical description of the relationship between undercoolings, lamellar spacings and growth velocities during the directional solidification of ternary eutectics in 2D and 3D, different extensions based on the theory of Jackson and Hunt are reported in the literature. Besides analytical approaches, the phase-field method has been established to study the spatially complex microstructure evolution during the solidification of eutectic alloys. The understanding of the fundamental mechanisms controlling the morphology development in multiphase, multicomponent systems is of high interest. For this purpose, a comparison is made between the analytical extensions and three-dimensional phase-field simulations of directional solidification in an ideal ternary eutectic system. Based on the observed accordance in two-dimensional validation cases, the experimentally reported, inherently three-dimensional chain-like pattern is investigated in extensive simulation studies. The results are quantitatively compared with the analytical results reported in the literature, and with a newly derived approach which uses equal undercoolings. A good accordance of the undercooling-spacing characteristics between simulations and the analytical Jackson-Hunt apporaches are found. The results show that the applied phase-field model, which is based on the Grand potential approach, is able to describe the analytically predicted relationship between the undercooling and the lamellar arrangements during the directional solidification of a ternary eutectic system in 3D.

An Approach for Multi-Artifact Testing Through an Ontological Perspective for Behavior-Driven Development

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Thiago Rocha Silva

2016-07-01

Full Text Available In a user-centered development process, artifacts evolve in iterative cycles until they meet users’ requirements and then become the final product. Every cycle gives the opportunity to revise the design and to introduce new requirements which might affect the specification of artifacts that have been set in former development phases. Testing the consistency of multiple artifacts used to develop interactive systems every time that new requirements are introduced is a cumbersome activity, especially if it is done manually. This paper proposes an approach based on Behavior-Driven Development (BDD to support the automated assessment of artifacts along the development process of interactive systems. The paper uses an ontology for specifying tests that can run over multiple artifacts sharing similar concepts. A case study testing Task Models, Prototypes, and Final User Interfaces is presented to demonstrate the feasibility of this approach from the early phases of the design process, providing a continuous quality assurance of requirements, and helping clients and development teams to identify potential problems and inconsistencies before commitments with software implementation are made.

Macroscopic polarization in crystalline dielectrics: the geometric phase approach

International Nuclear Information System (INIS)

Resta, R.

1994-01-01

The macroscopic electric polarization of a crystal is often defined as the dipole of a unit cell. In fact, such a dipole moment is ill defined, and the above definition is incorrect. Looking more closely, the quantity generally measured is differential polarization, defined with respect to a ''reference state'' of the same material. Such differential polarizations include either derivatives of the polarization (dielectric permittivity, Born effective charges, piezoelectricity, pyroelectricity) or finite differences (ferroelectricity). On the theoretical side, the differential concept is basic as well. Owing to continuity, a polarization difference is equivalent to a macroscopic current, which is directly accessible to the theory as a bulk property. Polarization is a quantum phenomenon and cannot be treated with a classical model, particularly whenever delocalized valence electrons are present in the dielectric. In a quantum picture, the current is basically a property of the phase of the wave functions, as opposed to the charge, which is a property of their modulus. An elegant and complete theory has recently been developed by King-Smith and Vanderbilt, in which the polarization difference between any two crystal states--in a null electric field--takes the form of a geometric quantum phase. This gives a comprehensive account of this theory, which is relevant for dealing with transverse-optic phonons, piezoelectricity, and ferroelectricity. Its relation to the established concepts of linear-response theory is also discussed. Within the geometric phase approach, the relevant polarization difference occurs as the circuit integral of a Berry connection (or ''vector potential''), while the corresponding curvature (or ''magnetic field'') provides the macroscopic linear response

Coherent state approach for the Φ6-lattice model and phase transitions

International Nuclear Information System (INIS)

Aguero-Granados, M.A.; Makhan'kov, V.G.

1991-01-01

Phase transitions in the lattice version of the Φ 6 -field theory are studied. The generalized coherent states approach to is used. In such a way the roles of kinks and bubbles in phase transitions have been reexamined. It is shown via a numerical analysis that first and second order phase transitions appear due to the behaviour of kinks and bubbles excitations. 12 refs.; 10 figs

A two-phased multi-criteria decision-making approach for selecting the best smartphone

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Yildiz, Aytac

2015-11-01

Full Text Available In the last 20 years, rapid and significant developments have occurred in communication and information technologies. In parallel with these developments, the importance of smartphones has increased. In addition, many smartphone manufacturers have launched and continue to launch a number of new models with many features. People who want to buy a new smartphone have difficulties selecting the best smartphone among the numerous models available on the technology markets. Therefore, smartphone selection has become a complex multi-criteria decision-making (MCDM problem for people. Hence, decision-making processes will be facilitated by using MCDM methods, and these will provide the most appropriate decision. In this paper, the best smartphone among the 28 alternatives determined by the person who will buy them are selected by using three main criteria and 17 sub-criteria with the help of a two-phased MCDM approach. In the first phase, 28 smartphone alternatives are ranked using the analytic network process (ANP. In the second phase, a model that includes the best four alternatives of ANP is created. Afterwards, the best smartphone is selected using the generalised Choquet integral (GCI method according to this model. Finally, the findings and the results are given.

Innovative Phase Change Approach for Significant Energy Savings

Science.gov (United States)

2016-09-01

related to the production, use, transmission , storage, control, or conservation of energy that will – (A) reduce the need for additional energy supplies...Conditions set for operation were: a. The computer with the broadband wireless card is to be used for data collection, transmission and...FINAL REPORT Innovative Phase Change Approach for Significant Energy Savings ESTCP Project EW-201138 SEPTEMBER 2016 Dr. Aly H Shaaban Applied

A strategic approach to developing e-learning capability for healthcare.

Science.gov (United States)

Clarke, Angie; Lewis, Dina; Cole, Ian; Ringrose, Liz

2005-12-01

This article examines a strategic approach to developing e-learning capability to enhance learning opportunities for the workforce of a healthcare organization. Emphasis is given to the procurement of a bespoke Managed Learning Environment (MLE). Strategic organizational issues impacting on future e-learning developments are considered. The 2-year implementation plan was evaluated through a two phase external research project. The first phase focused on the effectiveness of a training programme designed to build capacity for e-learning within the Northern area and also included a virtual learning environment usability study which informed the MLE specification. The second phase evaluation is ongoing during 2005 and interim findings are presented. The MLE has been piloted and on-line learning packages have been acquired. There has been a phased take-up of e-learning opportunities and e-tutor training. Some virtual Communities of Practice have been established. Key organizational issues have been identified and ongoing findings are informing strategic planning. The healthcare MLE is offering enhanced learning opportunities and assisting area healthcare providers in training their dispersed workforces. Blended learning strategies are most successful. The need for protected time for e-learning is a key issue, financial savings are available. Progress has been slowed by identified organizational constraints-the MLE's benefits are widely recognized.

Phases and Actions of the Evolution of the Concept of Quality in Canada and Australia – A Theoretical Modelling of the Development of Knowledge in Business Performance in the XXI Century - The Approach to Excellence

Directory of Open Access Journals (Sweden)

Cristina Raluca Popescu

2015-05-01

Full Text Available In the paper “Phases and Actions of the Evolution of the Concept of Quality in Canada and Australia – A Theoretical Modelling of the Development of Knowledge in Business Performance in the XXI Century - The Approach to Excellence” the authors present the basic features of the phases and actions of the evolution of the concept of quality in Canada and Australia, as a theoretical modelling of the development of knowledge in business performance in the XXI century in order to improve the organizational processes so that excellence can be achieved.

A Simple Approach to Characterize Gas-Aqueous Liquid Two-phase Flow Configuration Based on Discrete Solid-Liquid Contact Electrification.

Science.gov (United States)

Choi, Dongwhi; Lee, Donghyeon; Kim, Dong Sung

2015-10-14

In this study, we first suggest a simple approach to characterize configuration of gas-aqueous liquid two-phase flow based on discrete solid-liquid contact electrification, which is a newly defined concept as a sequential process of solid-liquid contact and successive detachment of the contact liquid from the solid surface. This approach exhibits several advantages such as simple operation, precise measurement, and cost-effectiveness. By using electric potential that is spontaneously generated by discrete solid-liquid contact electrification, the configurations of the gas-aqueous liquid two-phase flow such as size of a gas slug and flow rate are precisely characterized. According to the experimental and numerical analyses on parameters that affect electric potential, gas slugs have been verified to behave similarly to point electric charges when the measuring point of the electric potential is far enough from the gas slug. In addition, the configuration of the gas-aqueous liquid two-phase microfluidic system with multiple gas slugs is also characterized by using the presented approach. For a proof-of-concept demonstration of using the proposed approach in a self-triggered sensor, a gas slug detector with a counter system is developed to show its practicality and applicability.

A self-consistent phase-field approach to implicit solvation of charged molecules with Poisson–Boltzmann electrostatics

Science.gov (United States)

Sun, Hui; Wen, Jiayi; Zhao, Yanxiang; Li, Bo; McCammon, J. Andrew

2015-01-01

Dielectric boundary based implicit-solvent models provide efficient descriptions of coarse-grained effects, particularly the electrostatic effect, of aqueous solvent. Recent years have seen the initial success of a new such model, variational implicit-solvent model (VISM) [Dzubiella, Swanson, and McCammon Phys. Rev. Lett. 96, 087802 (2006) and J. Chem. Phys. 124, 084905 (2006)], in capturing multiple dry and wet hydration states, describing the subtle electrostatic effect in hydrophobic interactions, and providing qualitatively good estimates of solvation free energies. Here, we develop a phase-field VISM to the solvation of charged molecules in aqueous solvent to include more flexibility. In this approach, a stable equilibrium molecular system is described by a phase field that takes one constant value in the solute region and a different constant value in the solvent region, and smoothly changes its value on a thin transition layer representing a smeared solute-solvent interface or dielectric boundary. Such a phase field minimizes an effective solvation free-energy functional that consists of the solute-solvent interfacial energy, solute-solvent van der Waals interaction energy, and electrostatic free energy described by the Poisson–Boltzmann theory. We apply our model and methods to the solvation of single ions, two parallel plates, and protein complexes BphC and p53/MDM2 to demonstrate the capability and efficiency of our approach at different levels. With a diffuse dielectric boundary, our new approach can describe the dielectric asymmetry in the solute-solvent interfacial region. Our theory is developed based on rigorous mathematical studies and is also connected to the Lum–Chandler–Weeks theory (1999). We discuss these connections and possible extensions of our theory and methods. PMID:26723595

A self-consistent phase-field approach to implicit solvation of charged molecules with Poisson-Boltzmann electrostatics.

Science.gov (United States)

Sun, Hui; Wen, Jiayi; Zhao, Yanxiang; Li, Bo; McCammon, J Andrew

2015-12-28

Dielectric boundary based implicit-solvent models provide efficient descriptions of coarse-grained effects, particularly the electrostatic effect, of aqueous solvent. Recent years have seen the initial success of a new such model, variational implicit-solvent model (VISM) [Dzubiella, Swanson, and McCammon Phys. Rev. Lett. 96, 087802 (2006) and J. Chem. Phys. 124, 084905 (2006)], in capturing multiple dry and wet hydration states, describing the subtle electrostatic effect in hydrophobic interactions, and providing qualitatively good estimates of solvation free energies. Here, we develop a phase-field VISM to the solvation of charged molecules in aqueous solvent to include more flexibility. In this approach, a stable equilibrium molecular system is described by a phase field that takes one constant value in the solute region and a different constant value in the solvent region, and smoothly changes its value on a thin transition layer representing a smeared solute-solvent interface or dielectric boundary. Such a phase field minimizes an effective solvation free-energy functional that consists of the solute-solvent interfacial energy, solute-solvent van der Waals interaction energy, and electrostatic free energy described by the Poisson-Boltzmann theory. We apply our model and methods to the solvation of single ions, two parallel plates, and protein complexes BphC and p53/MDM2 to demonstrate the capability and efficiency of our approach at different levels. With a diffuse dielectric boundary, our new approach can describe the dielectric asymmetry in the solute-solvent interfacial region. Our theory is developed based on rigorous mathematical studies and is also connected to the Lum-Chandler-Weeks theory (1999). We discuss these connections and possible extensions of our theory and methods.

Development and testing of a new ray-tracing approach to GNSS carrier-phase multipath modelling

Science.gov (United States)

Lau, Lawrence; Cross, Paul

2007-11-01

Multipath is one of the most important error sources in Global Navigation Satellite System (GNSS) carrier-phase-based precise relative positioning. Its theoretical maximum is a quarter of the carrier wavelength (about 4.8 cm for the Global Positioning System (GPS) L1 carrier) and, although it rarely reaches this size, it must clearly be mitigated if millimetre-accuracy positioning is to be achieved. In most static applications, this may be accomplished by averaging over a sufficiently long period of observation, but in kinematic applications, a modelling approach must be used. This paper is concerned with one such approach: the use of ray-tracing to reconstruct the error and therefore remove it. In order to apply such an approach, it is necessary to have a detailed understanding of the signal transmitted from the satellite, the reflection process, the antenna characteristics and the way that the reflected and direct signal are processed within the receiver. This paper reviews all of these and introduces a formal ray-tracing method for multipath estimation based on precise knowledge of the satellite reflector antenna geometry and of the reflector material and antenna characteristics. It is validated experimentally using GPS signals reflected from metal, water and a brick building, and is shown to be able to model most of the main multipath characteristics. The method will have important practical applications for correcting for multipath in well-constrained environments (such as at base stations for local area GPS networks, at International GNSS Service (IGS) reference stations, and on spacecraft), and it can be used to simulate realistic multipath errors for various performance analyses in high-precision positioning.

Phase calibration approaches for radar interferometry and imaging configurations: equatorial spread F results

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J. L. Chau

2008-08-01

Full Text Available In recent years, more and more radar systems with multiple-receiver antennas are being used to study the atmospheric and ionospheric irregularities with either interferometric and/or imaging configurations. In such systems, one of the major challenges is to know the phase offsets between the different receiver channels. Such phases are intrinsic to the system and are due to different cable lengths, filters, attenuators, amplifiers, antenna impedance, etc. Moreover, such phases change as function of time, on different time scales, depending on the specific installation. In this work, we present three approaches using natural targets (radio stars, meteor-head and meteor trail echoes that allow either an absolute or relative phase calibration. In addition, we present the results of using an artificial source (radio beacon for a continuous calibration that complements the previous approaches. These approaches are robust and good alternatives to other approaches, e.g. self-calibration techniques using known data features, or for multiple-receiver configurations constantly changing their receiving elements. In order to show the good performance of the proposed phase calibration techniques, we present new radar imaging results of equatorial spread F (ESF irregularities. Finally we introduce a new way to represent range-time intensity (RTI maps color coded with the Doppler information. Such modified map allows the identification and interpretation of geophysical phenomena, previously hidden in conventional RTI maps, e.g. the time and altitude of occurrence of ESF irregularities pinching off from the bottomside and their respective Doppler velocity.

CFD model of diabatic annular two-phase flow using the Eulerian–Lagrangian approach

International Nuclear Information System (INIS)

Li, Haipeng; Anglart, Henryk

2015-01-01

Highlights: • A CFD model of annular two-phase flow with evaporating liquid film has been developed. • A two-dimensional liquid film model is developed assuming that the liquid film is sufficiently thin. • The liquid film model is coupled to the gas core flow, which is represented using the Eulerian–Lagrangian approach. - Abstract: A computational fluid dynamics (CFD) model of annular two-phase flow with evaporating liquid film has been developed based on the Eulerian–Lagrangian approach, with the objective to predict the dryout occurrence. Due to the fact that the liquid film is sufficiently thin in the diabatic annular flow and at the pre-dryout conditions, it is assumed that the flow in the wall normal direction can be neglected, and the spatial gradients of the dependent variables tangential to the wall are negligible compared to those in the wall normal direction. Subsequently the transport equations of mass, momentum and energy for liquid film are integrated in the wall normal direction to obtain two-dimensional equations, with all the liquid film properties depth-averaged. The liquid film model is coupled to the gas core flow, which currently is represented using the Eulerian–Lagrangian technique. The mass, momentum and energy transfers between the liquid film, gas, and entrained droplets have been taken into account. The resultant unified model for annular flow has been applied to the steam–water flow with conditions typical for a Boiling Water Reactor (BWR). The simulation results for the liquid film flow rate show favorable agreement with the experimental data, with the potential to predict the dryout occurrence based on criteria of critical film thickness or critical film flow rate

Combined mixed approach algorithm for in-line phase-contrast x-ray imaging

International Nuclear Information System (INIS)

De Caro, Liberato; Scattarella, Francesco; Giannini, Cinzia; Tangaro, Sabina; Rigon, Luigi; Longo, Renata; Bellotti, Roberto

2010-01-01

Purpose: In the past decade, phase-contrast imaging (PCI) has been applied to study different kinds of tissues and human body parts, with an increased improvement of the image quality with respect to simple absorption radiography. A technique closely related to PCI is phase-retrieval imaging (PRI). Indeed, PCI is an imaging modality thought to enhance the total contrast of the images through the phase shift introduced by the object (human body part); PRI is a mathematical technique to extract the quantitative phase-shift map from PCI. A new phase-retrieval algorithm for the in-line phase-contrast x-ray imaging is here proposed. Methods: The proposed algorithm is based on a mixed transfer-function and transport-of-intensity approach (MA) and it requires, at most, an initial approximate estimate of the average phase shift introduced by the object as prior knowledge. The accuracy in the initial estimate determines the convergence speed of the algorithm. The proposed algorithm retrieves both the object phase and its complex conjugate in a combined MA (CMA). Results: Although slightly less computationally effective with respect to other mixed-approach algorithms, as two phases have to be retrieved, the results obtained by the CMA on simulated data have shown that the obtained reconstructed phase maps are characterized by particularly low normalized mean square errors. The authors have also tested the CMA on noisy experimental phase-contrast data obtained by a suitable weakly absorbing sample consisting of a grid of submillimetric nylon fibers as well as on a strongly absorbing object made of a 0.03 mm thick lead x-ray resolution star pattern. The CMA has shown a good efficiency in recovering phase information, also in presence of noisy data, characterized by peak-to-peak signal-to-noise ratios down to a few dBs, showing the possibility to enhance with phase radiography the signal-to-noise ratio for features in the submillimetric scale with respect to the attenuation

First-order system least squares and the energetic variational approach for two-phase flow

Science.gov (United States)

Adler, J. H.; Brannick, J.; Liu, C.; Manteuffel, T.; Zikatanov, L.

2011-07-01

This paper develops a first-order system least-squares (FOSLS) formulation for equations of two-phase flow. The main goal is to show that this discretization, along with numerical techniques such as nested iteration, algebraic multigrid, and adaptive local refinement, can be used to solve these types of complex fluid flow problems. In addition, from an energetic variational approach, it can be shown that an important quantity to preserve in a given simulation is the energy law. We discuss the energy law and inherent structure for two-phase flow using the Allen-Cahn interface model and indicate how it is related to other complex fluid models, such as magnetohydrodynamics. Finally, we show that, using the FOSLS framework, one can still satisfy the appropriate energy law globally while using well-known numerical techniques.

Schistosomiasis vaccine development: approaches and prospects

Directory of Open Access Journals (Sweden)

N. R. Bergquist

1995-04-01

Full Text Available Mounting evidence for acquired immunity to schistosomiasis in humans supports the case for immunological intervention. On the other hand, rapid reinfection poses a threat to younger age groups due to the slow maturation of natural resistance. However, rational approaches, based on advances in immunology and molecular biology, have substantially increased the odds of producing an effective vaccine. Since the parasite cannot replicate in the human host and serious morbidity generally occurs only after a relatively long period of heavy worm burden, complete protection against infection is not essential. The chances of success would increase if more than one of the various host/parasite interphases were targeted, for example reducing morbidity through decreased worm loads as well as through suppression of egg production. Several promising schistosome antigens have now reached an advanced phase of development and are currently undergoing independent confirmatory testing according to a standardized protocol. A few molecules are being contemplated for scaled-up production but, so far, only one has reached the stage of industrial manufacture and safety testing. Since schistosomiasis cannot realistically be controlled by a single approach, vaccination is envisaged to be implemented in conjunction with other means of control, notably chemotherapy.

Nonperturbative approach to quantum field theories: phase transitions and confinement

International Nuclear Information System (INIS)

Yankielowicz, S.

1976-08-01

Lectures are given on a nonperturbative approach to quantum field theories. Phenomena are discussed for which the usual weak coupling perturbative approach in terms of Feynman diagrams is of no assistance. Properties associated with large distance behavior, i.e., phase transitions, low lying spectra, coherent excitations which are presumably built out of the long wave structure of the theory are described. These methods are important for the study of strong coupling field theories and the question of quarks confinement. 25 references

Development and application of a biorelevant dissolution method using USP apparatus 4 in early phase formulation development.

Science.gov (United States)

Fang, Jiang B; Robertson, Vivian K; Rawat, Archana; Flick, Tawnya; Tang, Zhe J; Cauchon, Nina S; McElvain, James S

2010-10-04

Dissolution testing is frequently used to determine the rate and extent at which a drug is released from a dosage form, and it plays many important roles throughout drug product development. However, the traditional dissolution approach often emphasizes its application in quality control testing and usually strives to obtain 100% drug release. As a result, dissolution methods are not necessarily biorelevant and meaningful application of traditional dissolution methods in the early phases of drug product development can be very limited. This article will describe the development of a biorelevant in vitro dissolution method using USP apparatus 4, biorelevant media, and real-time online UV analysis. Several case studies in the areas of formulation selection, lot-to-lot variability, and food effect will be presented to demonstrate the application of this method in early phase formulation development. This biorelevant dissolution method using USP apparatus 4 provides a valuable tool to predict certain aspects of the in vivo drug release. It can be used to facilitate the formulation development/selection for pharmacokinetic (PK) and clinical studies. It may also potentially be used to minimize the number of PK studies, and to aid in the design of more efficient PK and clinical studies.

Use of Probabilistic Engineering Methods in the Detailed Design and Development Phases of the NASA Ares Launch Vehicle

Science.gov (United States)

Fayssal, Safie; Weldon, Danny

2008-01-01

The United States National Aeronautics and Space Administration (NASA) is in the midst of a space exploration program called Constellation to send crew and cargo to the international Space Station, to the moon, and beyond. As part of the Constellation program, a new launch vehicle, Ares I, is being developed by NASA Marshall Space Flight Center. Designing a launch vehicle with high reliability and increased safety requires a significant effort in understanding design variability and design uncertainty at the various levels of the design (system, element, subsystem, component, etc.) and throughout the various design phases (conceptual, preliminary design, etc.). In a previous paper [1] we discussed a probabilistic functional failure analysis approach intended mainly to support system requirements definition, system design, and element design during the early design phases. This paper provides an overview of the application of probabilistic engineering methods to support the detailed subsystem/component design and development as part of the "Design for Reliability and Safety" approach for the new Ares I Launch Vehicle. Specifically, the paper discusses probabilistic engineering design analysis cases that had major impact on the design and manufacturing of the Space Shuttle hardware. The cases represent important lessons learned from the Space Shuttle Program and clearly demonstrate the significance of probabilistic engineering analysis in better understanding design deficiencies and identifying potential design improvement for Ares I. The paper also discusses the probabilistic functional failure analysis approach applied during the early design phases of Ares I and the forward plans for probabilistic design analysis in the detailed design and development phases.

Mechanical disequilibria in two-phase flow models: approaches by relaxation and by a reduced model

International Nuclear Information System (INIS)

Labois, M.

2008-10-01

This thesis deals with hyperbolic models for the simulation of compressible two-phase flows, to find alternatives to the classical bi-fluid model. We first establish a hierarchy of two-phase flow models, obtained according to equilibrium hypothesis between the physical variables of each phase. The use of Chapman-Enskog expansions enables us to link the different existing models to each other. Moreover, models that take into account small physical unbalances are obtained by means of expansion to the order one. The second part of this thesis focuses on the simulation of flows featuring velocity unbalances and pressure balances, in two different ways. First, a two-velocity two-pressure model is used, where non-instantaneous velocity and pressure relaxations are applied so that a balancing of these variables is obtained. A new one-velocity one-pressure dissipative model is then proposed, where the arising of second-order terms enables us to take into account unbalances between the phase velocities. We develop a numerical method based on a fractional step approach for this model. (author)

Imaging phase holdup distribution of three phase flow systems using dual source gamma ray tomography

International Nuclear Information System (INIS)

Varma, Rajneesh; Al-Dahhan, Muthanna; O'Sullivan, Joseph

2008-01-01

Full text: Multiphase reaction and process systems are used in abundance in the chemical and biochemical industry. Tomography has been successfully employed to visualize the hydrodynamics of multiphase systems. Most of the tomography methods (gamma ray, x-ray and electrical capacitance and resistance) have been successfully implemented for two phase dynamic systems. However, a significant number of chemical and biochemical systems consists of dynamic three phases. Research effort directed towards the development of tomography techniques to image such dynamic system has met with partial successes for specific systems with applicability to limited operating conditions. A dual source tomography scanner has been developed that uses the 661 keV and 1332 keV photo peaks from the 137 Cs and 60 Co for imaging three phase systems. A new approach has been developed and applied that uses the polyenergetic Alternating Minimization (A-M) algorithm, developed by O'Sullivan and Benac (2007), for imaging the holdup distribution in three phases' dynamic systems. The new approach avoids the traditional post image processing approach used to determine the holdup distribution where the attenuation images of the mixed flow obtained from gamma ray photons of two different energies are used to determine the holdup of three phases. In this approach the holdup images are directly reconstructed from the gamma ray transmission data. The dual source gamma ray tomography scanner and the algorithm were validated using a three phase phantom. Based in the validation, three phase holdup studies we carried out in slurry bubble column containing gas liquid and solid phases in a dynamic state using the dual energy gamma ray tomography. The key results of the holdup distribution studies in the slurry bubble column along with the validation of the dual source gamma ray tomography system would be presented and discussed

Phases, phase equilibria, and phase rules in low-dimensional systems

International Nuclear Information System (INIS)

Frolov, T.; Mishin, Y.

2015-01-01

We present a unified approach to thermodynamic description of one, two, and three dimensional phases and phase transformations among them. The approach is based on a rigorous definition of a phase applicable to thermodynamic systems of any dimensionality. Within this approach, the same thermodynamic formalism can be applied for the description of phase transformations in bulk systems, interfaces, and line defects separating interface phases. For both lines and interfaces, we rigorously derive an adsorption equation, the phase coexistence equations, and other thermodynamic relations expressed in terms of generalized line and interface excess quantities. As a generalization of the Gibbs phase rule for bulk phases, we derive phase rules for lines and interfaces and predict the maximum number of phases than may coexist in systems of the respective dimensionality

An Efficient and Packing-Resilient Two-Phase Android Cloned Application Detection Approach

Directory of Open Access Journals (Sweden)

Fang Lyu

2017-01-01

Full Text Available The huge benefit of mobile application industry has attracted a large number of developers and attendant attackers. Application repackaging provides help for the distribution of most Android malware. It is a serious threat to the entire Android ecosystem, as it not only compromises the security and privacy of the app users but also plunders app developers’ income. Although massive approaches have been proposed to address this issue, plagiarists try to fight back through packing their malicious code with the help of commercial packers. Previous works either do not consider the packing issue or rely on time-consuming computations, which are not scalable for large-scale real-world scenario. In this paper, we propose FUIDroid, a novel two-phase app clones detection system that can detect the packed cloned app. FUIDroid includes a function-based fast selection phase to quickly select suspicious apps by analyzing apps’ description and a further UI-based accurate detection phase to refine the detection result. We evaluate our system on two sets of apps. The result from experiment on 320 packed samples demonstrates that FUIDroid is resilient to packed apps. The evaluation on more than 150,000 real-world apps shows the efficiency of FUIDroid in large-scale scenario.

QCD phase transition at real chemical potential with canonical approach

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Atsushi [RCNP, Osaka University,Osaka, 567-0047 (Japan); Nishina Center, RIKEN,Wako, Saitama 351-0198 (Japan); School of Biomedicine, Far Eastern Federal University,Vladivostok, 690950 (Russian Federation); Oka, Shotaro [Institute of Theoretical Physics, Department of Physics, Rikkyo University,Toshima-ku, Tokyo 171-8501 (Japan); Taniguchi, Yusuke [Graduate School of Pure and Applied Sciences, University of Tsukuba,Tsukuba, Ibaraki 305-8571 (Japan)

2016-02-08

We study the finite density phase transition in the lattice QCD at real chemical potential. We adopt a canonical approach and the canonical partition function is constructed for N{sub f}=2 QCD. After derivation of the canonical partition function we calculate observables like the pressure, the quark number density, its second cumulant and the chiral condensate as a function of the real chemical potential. We covered a wide range of temperature region starting from the confining low to the deconfining high temperature; 0.65T{sub c}≤T≤3.62T{sub c}. We observe a possible signal of the deconfinement and the chiral restoration phase transition at real chemical potential below T{sub c} starting from the confining phase. We give also the convergence range of the fugacity expansion.

Risk management in medical product development process using traditional FMEA and fuzzy linguistic approach: a case study

Science.gov (United States)

Kirkire, Milind Shrikant; Rane, Santosh B.; Jadhav, Jagdish Rajaram

2015-12-01

Medical product development (MPD) process is highly multidisciplinary in nature, which increases the complexity and the associated risks. Managing the risks during MPD process is very crucial. The objective of this research is to explore risks during MPD in a dental product manufacturing company and propose a model for risk mitigation during MPD process to minimize failure events. A case study approach is employed. The existing MPD process is mapped with five phases of the customized phase gate process. The activities during each phase of development and risks associated with each activity are identified and categorized based on the source of occurrence. The risks are analyzed using traditional Failure mode and effect analysis (FMEA) and fuzzy FMEA. The results of two methods when compared show that fuzzy approach avoids the duplication of RPNs and helps more to convert cognition of experts into information to get values of risk factors. The critical, moderate, low level and negligible risks are identified based on criticality; risk treatments and mitigation model are proposed. During initial phases of MPD, the risks are less severe, but as the process progresses the severity of risks goes on increasing. The MPD process should be critically designed and simulated to minimize the number of risk events and their severity. To successfully develop the products/devices within the manufacturing companies, the process risk management is very essential. A systematic approach to manage risks during MPD process will lead to the development of medical products with expected quality and reliability. This is the first research of its kind having focus on MPD process risks and its management. The methodology adopted in this paper will help the developers, managers and researchers to have a competitive edge over the other companies by managing the risks during the development process.

Approaching Pomeranchuk instabilities from ordered phase: A crossing-symmetric equation method

International Nuclear Information System (INIS)

Reidy, Kelly; Quader, Khandker; Bedell, Kevin

2014-01-01

We explore features of a 3D Fermi liquid near generalized Pomeranchuk instabilities using a tractable crossing-symmetric equation method. We approach the instabilities from the ordered ferromagnetic phase. We find “quantum multi-criticality” as approach to the ferromagnetic instability drives instability in other channel(s). It is found that a charge nematic instability precedes and is driven by Pomeranchuk instabilities in both the ℓ=0 spin and density channels

Modelling production system architectures in the early phases of product development

DEFF Research Database (Denmark)

Guðlaugsson, Tómas Vignir; Ravn, Poul Martin; Mortensen, Niels Henrik

2016-01-01

are needed and appropriate to enable determination of obtainable product quality. In order to meet this challenge, it is suggested that a visual modelling framework be adopted that clarifies which product and production features are known at a specific time of the project and which features will be worked...... on – leading to an improved basis for prioritizing activities in the project. Requirements for the contents of the framework are presented, and literature on production and system models is reviewed. The production system architecture modelling framework is founded on methods and approaches in literature......This article suggests a framework for modelling a production system architecture in the early phases of product development.The challenge in these phases is that the products to be produced are not completely defined and yet decisions need to be made early in the process on what investments...

Current Trend Towards Using Soft Computing Approaches to Phase Synchronization in Communication Systems

Science.gov (United States)

Drake, Jeffrey T.; Prasad, Nadipuram R.

1999-01-01

This paper surveys recent advances in communications that utilize soft computing approaches to phase synchronization. Soft computing, as opposed to hard computing, is a collection of complementary methodologies that act in producing the most desirable control, decision, or estimation strategies. Recently, the communications area has explored the use of the principal constituents of soft computing, namely, fuzzy logic, neural networks, and genetic algorithms, for modeling, control, and most recently for the estimation of phase in phase-coherent communications. If the receiver in a digital communications system is phase-coherent, as is often the case, phase synchronization is required. Synchronization thus requires estimation and/or control at the receiver of an unknown or random phase offset.

Combined object-oriented approach for development of process control systems

International Nuclear Information System (INIS)

Antonova, I.; Batchkova, I.

2013-01-01

Full text: The traditional approaches for development of software control system in automation an information technology based on a directly code creation are no longer effective and successful enough. The response to these challenges is the Model Driven Engineering (MDE) or its counter part in the field of architectures Model Driven Architecture (MDA). One of the most promising approach supporting MDE and MDA is UML. It does not specify a methodology for software or system design but aims to provide an integrated modeling framework for structural, functional and behavior descriptions. The success of UML in many object-oriented approaches led to an idea of applying UML to design of multi agent systems. The approach proposed in this paper applies modified Harmony methodology and is based on the combined use of UML profile for system engineering, IEC61499 standard and FIPA standard protocols. The benefits of object-oriented paradigm and the models of IEC61499 standard are extended with UML/SysML and FIPA notations. The development phases are illustrated with the UML models of a simple process control system. The main benefits of using the proposed approach can be summarized as: it provides consistency in the syntax and underlying semantics; increases the potential and likelihood of reuse; supports the whole software development life cycle in the field of process control. Including the SysML features, based on extended activity and parametric diagrams, flow ports and items to the proposed approach opens the possibilities for modeling of continuous system and support the development in field of process control. Another advantage, connected to the UML/MARTE profile is the possibility for analysis of the designed system and detailed design of the hardware and software platform of the modeled application. Key words: object-oriented modeling, control system, UML, SysML, IEC 61499

On the stress calculation within phase-field approaches: a model for finite deformations

Science.gov (United States)

Schneider, Daniel; Schwab, Felix; Schoof, Ephraim; Reiter, Andreas; Herrmann, Christoph; Selzer, Michael; Böhlke, Thomas; Nestler, Britta

2017-08-01

Numerical simulations based on phase-field methods are indispensable in order to investigate interesting and important phenomena in the evolution of microstructures. Microscopic phase transitions are highly affected by mechanical driving forces and therefore the accurate calculation of the stresses in the transition region is essential. We present a method for stress calculations within the phase-field framework, which satisfies the mechanical jump conditions corresponding to sharp interfaces, although the sharp interface is represented as a volumetric region using the phase-field approach. This model is formulated for finite deformations, is independent of constitutive laws, and allows using any type of phase inherent inelastic strains.

Phase retrieval for X-ray in-line phase contrast imaging

International Nuclear Information System (INIS)

Scattarella, F.; Bellotti, R.; Tangaro, S.; Gargano, G.; Giannini, C.

2011-01-01

A review article about phase retrieval problem in X-ray phase contrast imaging is presented. A simple theoretical framework of Fresnel diffraction imaging by X-rays is introduced. A review of the most important methods for phase retrieval in free-propagation-based X-ray imaging and a new method developed by our collaboration are shown. The proposed algorithm, Combined Mixed Approach (CMA) is based on a mixed transfer function and transport of intensity approach, and it requires at most an initial approximate estimate of the average phase shift introduced by the object as prior knowledge. The accuracy with which this initial estimate is known determines the convenience speed of algorithm. The new proposed algorithm is based on the retrieval of both the object phase and its complex conjugate. The results obtained by the algorithm on simulated data have shown that the obtained reconstructed phase maps are characterized by particularly low normalized mean square errors. The algorithm was also tested on noisy experimental phase contrast data, showing a good efficiency in recovering phase information and enhancing the visibility of details inside soft tissues.

New modeling and experimental approaches for characterization of two-phase flow interfacial structure

International Nuclear Information System (INIS)

Ishii, Mamoru; Sun, Xiaodong

2004-01-01

This paper presents new experimental and modeling approaches in characterizing interfacial structures in gas-liquid two-phase flow. For the experiments, two objective approaches are developed to identify flow regimes and to obtain local interfacial structure data. First, a global measurement technique using a non-intrusive ring-type impedance void-meter and a self-organizing neural network is presented to identify the one-dimensional'' flow regimes. In the application of this measurement technique, two methods are discussed, namely, one based on the probability density function of the impedance probe measurement (PDF input method) and the other based on the sorted impedance signals, which is essentially the cumulative probability distribution function of the impedance signals (instantaneous direct signal input method). In the latter method, the identification can be made close to instantaneously since the required signals can be acquired over a very short time period. In addition, a double-sensor conductivity probe can also be used to obtain ''local'' flow regimes by using the instantaneous direct signal input method with the bubble chord length information. Furthermore, a newly designed conductivity probe with multiple double-sensor heads is proposed to obtain ''two-dimensional'' flow regimes across the flow channel. Secondly, a state-of-the-art four-sensor conductivity probe technique has been developed to obtain detailed local interfacial structure information. The four-sensor conductivity probe accommodates the double-sensor probe capability and can be applied in a wide range of flow regimes spanning from bubbly to churn-turbulent flows. The signal processing scheme is developed such that it categorizes the acquired parameters into two groups based on bubble cord length information. Furthermore, for the modeling of the interfacial structure characterization, the interfacial area transport equation proposed earlier has been studied to provide a dynamic and

Deconfinement phase transition in the Hamiltonian approach to Yang–Mills theory in Coulomb gauge

Directory of Open Access Journals (Sweden)

Reinhardt H.

2014-04-01

Full Text Available Recent results obtained for the deconfinement phase transition within the Hamiltonian approach to Yang–Mills theory are reviewed. Assuming a quasiparticle picture for the grand canonical gluon ensemble the thermal equilibrium state is found by minimizing the free energy with respect to the quasi-gluon energy. The deconfinement phase transition is accompanied by a drastic change of the infrared exponents of the ghost and gluon propagators. Above the phase transition the ghost form factor remains infrared divergent but its infrared exponent is approximately halved. The gluon energy being infrared divergent in the confined phase becomes infrared finite in the deconfined phase. Furthermore, the effective potential of the order parameter for confinement is calculated for SU(N Yang–Mills theory in the Hamiltonian approach by compactifying one spatial dimension and using a background gauge fixing. In the simplest truncation, neglecting the ghost and using the ultraviolet form of the gluon energy, we recover the Weiss potential. From the full non-perturbative potential (with the ghost included we extract a critical temperature of the deconfinement phase transition of 269 MeV for the gauge group SU(2 and 283 MeV for SU(3.

New Approaches in Soil Organic Matter Fluorescence; A Solid Phase Fluorescence Approach

Science.gov (United States)

Bowman, M. M.; Sanclements, M.; McKnight, D. M.

2017-12-01

Fluorescence spectroscopy is a well-established technique to investigate the composition of organic matter in aquatic systems and is increasingly applied to soil organic matter (SOM). Current methods require that SOM be extracted into a liquid prior to analysis by fluorescence spectroscopy. Soil extractions introduce an additional layer of complexity as the composition of the organic matter dissolved into solution varies based upon the selected extractant. Water is one of the most commonly used extractant, but only extracts the water-soluble fraction of the SOM with the insoluble soil organic matter fluorescence remaining in the soil matrix. We propose the use of solid phase fluorescence on whole soils as a potential tool to look at the composition of organic matter without the extraction bias and gain a more complete understand of the potential for fluorescence as a tool in terrestrial studies. To date, the limited applications of solid phase fluorescence have ranged from food and agriculture to pharmaceutical with no clearly defined methods and limitations available. We are aware of no other studies that use solid phase fluorescence and thus no clear methods to look at SOM across a diverse set of soil types and ecosystems. With this new approach to fluorescence spectroscopy there are new challenges, such as blank correction, inner filter effect corrections, and sample preparation. This work outlines a novel method for analyzing soil organic matter using solid phase fluorescence across a wide range of soils collected from the National Ecological Observatory Network (NEON) eco-domains. This method has shown that organic matter content in soils must be diluted to 2% to reduce backscattering and oversaturation of the detector in forested soils. In mineral horizons (A) there is observed quenching of the humic-like organic matter, which is likely a result of organo-mineral complexation. Finally, we present preliminary comparisons between solid and liquid phase

Nonstationary signals phase-energy approach-theory and simulations

CERN Document Server

Klein, R; Braun, S; 10.1006/mssp.2001.1398

2001-01-01

Modern time-frequency methods are intended to deal with a variety of nonstationary signals. One specific class, prevalent in the area of rotating machines, is that of harmonic signals of varying frequencies and amplitude. This paper presents a new adaptive phase-energy (APE) approach for time-frequency representation of varying harmonic signals. It is based on the concept of phase (frequency) paths and the instantaneous power spectral density (PSD). It is this path which represents the dynamic behaviour of the system generating the observed signal. The proposed method utilises dynamic filters based on an extended Nyquist theorem, enabling extraction of signal components with optimal signal-to-noise ratio. The APE detects the most energetic harmonic components (frequency paths) in the analysed signal. Tests on simulated signals show the superiority of the APE in resolution and resolving power as compared to STFT and wavelets wave- packet decomposition. The dynamic filters also enable the reconstruction of the ...

Incorporating the CALPHAD sublattice approach of ordering into the phase-field model with finite interface dissipation

International Nuclear Information System (INIS)

Zhang, Lijun; Stratmann, Matthias; Du, Yong; Sundman, Bo; Steinbach, Ingo

2015-01-01

A new approach to incorporate the sublattice models in the CALPHAD (CALculation of PHAse Diagram) formalism directly into the phase-field formalism is developed. In binary alloys, the sublattice models can be classified into two types (i.e., “Type I” and “Type II”), depending on whether a direct one-to-one relation between the element site fraction in the CALPHAD database and the phase concentration in the phase-field model exists (Type I), or not (Type II). For “Type II” sublattice models, the specific site fractions, corresponding to a given mole fraction, have to be established via internal relaxation between different sublattices. Internal minimization of sublattice occupancy and solute evolution during microstructure transformation leads, in general, to a solution superior to the separate solution of the individual problems. The present coupling technique is validated for Fe–C and Ni–Al alloys. Finally, the model is extended into multicomponent alloys and applied to simulate the nucleation process of VC monocarbide from austenite matrix in a steel containing vanadium

A multidisciplinary three-phase approach to improve the clinical utility of patient safety indicators.

Science.gov (United States)

Najjar, Peter; Kachalia, Allen; Sutherland, Tori; Beloff, Jennifer; David-Kasdan, Jo Ann; Bates, David W; Urman, Richard D

2015-01-01

The AHRQ Patient Safety Indicators (PSIs) are used for calculation of risk-adjusted postoperative rates for adverse events. The payers and quality consortiums are increasingly requiring public reporting of hospital performance on these metrics. We discuss processes designed to improve the accuracy and clinical utility of PSI reporting in practice. The study was conducted at a 793-bed tertiary care academic medical center where PSI processes have been aggressively implemented to track patient safety events at discharge. A three-phased approach to improving administrative data quality was implemented. The initiative consisted of clinical review of all PSIs, documentation improvement, and provider outreach including active querying for patient safety events. This multidisciplinary effort to develop a streamlined process for PSI calculation reduced the reporting of miscoded PSIs and increased the clinical utility of PSI monitoring. Over 4 quarters, 4 of 41 (10%) PSI-11 and 9 of 138 (7%) PSI-15 errors were identified on review of clinical documentation and appropriate adjustments were made. A multidisciplinary, phased approach leveraging existing billing infrastructure for robust metric coding, ongoing clinical review, and frontline provider outreach is a novel and effective way to reduce the reporting of false-positive outcomes and improve the clinical utility of PSIs.

Random phase approximation in relativistic approach

International Nuclear Information System (INIS)

Ma Zhongyu; Yang Ding; Tian Yuan; Cao Ligang

2009-01-01

Some special issues of the random phase approximation(RPA) in the relativistic approach are reviewed. A full consistency and proper treatment of coupling to the continuum are responsible for the successful application of the RPA in the description of dynamical properties of finite nuclei. The fully consistent relativistic RPA(RRPA) requires that the relativistic mean filed (RMF) wave function of the nucleus and the RRPA correlations are calculated in a same effective Lagrangian and the consistent treatment of the Dirac sea of negative energy states. The proper treatment of the single particle continuum with scattering asymptotic conditions in the RMF and RRPA is discussed. The full continuum spectrum can be described by the single particle Green's function and the relativistic continuum RPA is established. A separable form of the paring force is introduced in the relativistic quasi-particle RPA. (authors)

Quantifying Neural Oscillatory Synchronization: A Comparison between Spectral Coherence and Phase-Locking Value Approaches

Science.gov (United States)

Lowet, Eric; Roberts, Mark J.; Bonizzi, Pietro; Karel, Joël; De Weerd, Peter

2016-01-01

Synchronization or phase-locking between oscillating neuronal groups is considered to be important for coordination of information among cortical networks. Spectral coherence is a commonly used approach to quantify phase locking between neural signals. We systematically explored the validity of spectral coherence measures for quantifying synchronization among neural oscillators. To that aim, we simulated coupled oscillatory signals that exhibited synchronization dynamics using an abstract phase-oscillator model as well as interacting gamma-generating spiking neural networks. We found that, within a large parameter range, the spectral coherence measure deviated substantially from the expected phase-locking. Moreover, spectral coherence did not converge to the expected value with increasing signal-to-noise ratio. We found that spectral coherence particularly failed when oscillators were in the partially (intermittent) synchronized state, which we expect to be the most likely state for neural synchronization. The failure was due to the fast frequency and amplitude changes induced by synchronization forces. We then investigated whether spectral coherence reflected the information flow among networks measured by transfer entropy (TE) of spike trains. We found that spectral coherence failed to robustly reflect changes in synchrony-mediated information flow between neural networks in many instances. As an alternative approach we explored a phase-locking value (PLV) method based on the reconstruction of the instantaneous phase. As one approach for reconstructing instantaneous phase, we used the Hilbert Transform (HT) preceded by Singular Spectrum Decomposition (SSD) of the signal. PLV estimates have broad applicability as they do not rely on stationarity, and, unlike spectral coherence, they enable more accurate estimations of oscillatory synchronization across a wide range of different synchronization regimes, and better tracking of synchronization-mediated information

Quantifying Neural Oscillatory Synchronization: A Comparison between Spectral Coherence and Phase-Locking Value Approaches.

Directory of Open Access Journals (Sweden)

Eric Lowet

Full Text Available Synchronization or phase-locking between oscillating neuronal groups is considered to be important for coordination of information among cortical networks. Spectral coherence is a commonly used approach to quantify phase locking between neural signals. We systematically explored the validity of spectral coherence measures for quantifying synchronization among neural oscillators. To that aim, we simulated coupled oscillatory signals that exhibited synchronization dynamics using an abstract phase-oscillator model as well as interacting gamma-generating spiking neural networks. We found that, within a large parameter range, the spectral coherence measure deviated substantially from the expected phase-locking. Moreover, spectral coherence did not converge to the expected value with increasing signal-to-noise ratio. We found that spectral coherence particularly failed when oscillators were in the partially (intermittent synchronized state, which we expect to be the most likely state for neural synchronization. The failure was due to the fast frequency and amplitude changes induced by synchronization forces. We then investigated whether spectral coherence reflected the information flow among networks measured by transfer entropy (TE of spike trains. We found that spectral coherence failed to robustly reflect changes in synchrony-mediated information flow between neural networks in many instances. As an alternative approach we explored a phase-locking value (PLV method based on the reconstruction of the instantaneous phase. As one approach for reconstructing instantaneous phase, we used the Hilbert Transform (HT preceded by Singular Spectrum Decomposition (SSD of the signal. PLV estimates have broad applicability as they do not rely on stationarity, and, unlike spectral coherence, they enable more accurate estimations of oscillatory synchronization across a wide range of different synchronization regimes, and better tracking of synchronization

A Model of e-Learning by Constructivism Approach Using Problem-Based Learning to Develop Thinking Skills for Students in Rajaghat University

Science.gov (United States)

Shutimarrungson, Werayut; Pumipuntu, Sangkom; Noirid, Surachet

2014-01-01

This research aimed to develop a model of e-learning by using Problem-Based Learning--PBL to develop thinking skills for students in Rajabhat University. The research is divided into three phases through the e-learning model via PBL with Constructivism approach as follows: Phase 1 was to study characteristics and factors through the model to…

A numerical approach to the simulation of one-phase and two phase reactor coolant flow around nuclear fuel spacers

International Nuclear Information System (INIS)

Stosic, Z.V.; Stevanovic, V.D.

2001-01-01

A methodology for the simulation and analysis of one-phase and two-phase coolant flows around one or a row of spacers is presented. It is based on the multidimensional two-fluid mass, momentum and energy balance equations and application of adequate turbulence models. Necessary closure laws for interfacial transfer processes are presented. The stated general approach enables simulation and analyses of reactor coolant flow around spacers on different scale levels of the rod bundle geometry: detailed modelling of coolant flow around spacers and investigation of the influence of spacer's geometry on the coolant thermal-hydraulics, as well as prediction of global thermal-hydraulic parameters within the whole rod bundle with the investigation of the influence of rows of spacers on the bulk thermal-hydraulic processes. Sample problems are included illustrating these different modelling approaches. (author)

Development and experimental evaluation of models for low capillary number two-phase flows in rough walled fractures relevant to natural gradient conditions

International Nuclear Information System (INIS)

Glass, R.J.; Yarrington, L.; Nicholl, M.J.

1997-09-01

The major results from SNL's Conceptual Model Development and Validation Task (WBS 1.2.5.4.6) as developed through exploration of small scale processes were synthesized in Glass et al. to give guidance to Performance Assessment on improving conceptual models for isothermal flow in unsaturated, fractured rock. There, pressure saturation and relative permeability curves for single fractures were proposed to be a function of both fracture orientation within the gravity field and initial conditions. We refer the reader to Glass et al. for a discussion of the implications of this behavior for Performance Assessment. The scientific research we report here substantiates this proposed behavior. We address the modeling of phase structure within fractures under natural gradient conditions relevant to unsaturated flow through fractures. This phase structure underlies the calculation of effective properties for individual fractures and hence fracture networks as required for Performance Assessment. Standard Percolation (SP) and Invasion Percolation (IP) approaches have been recently proposed to model the underlying phase saturation structures within the individual fractures during conditions of two-phase flow. Subsequent analysis of these structures yields effective two-phase pressure-saturation and relative permeability relations for the fracture. However, both of these approaches yield structures that are at odds with physical reality as we see in experiments and thus effective properties calculated from these structures are in error. Here we develop and evaluate a Modified Invasion Percolation (MIP) approach to better model quasi-static immiscible displacement in fractures. The effects of gravity, contact angle, local aperature field geometry, and local in-plane interfacial curvature between phases are included in the calculation of invasion pressure for individual sites in a discretized aperture field

A regularized, model-based approach to phase-based conductivity mapping using MRI.

Science.gov (United States)

Ropella, Kathleen M; Noll, Douglas C

2017-11-01

To develop a novel regularized, model-based approach to phase-based conductivity mapping that uses structural information to improve the accuracy of conductivity maps. The inverse of the three-dimensional Laplacian operator is used to model the relationship between measured phase maps and the object conductivity in a penalized weighted least-squares optimization problem. Spatial masks based on structural information are incorporated into the problem to preserve data near boundaries. The proposed Inverse Laplacian method was compared against a restricted Gaussian filter in simulation, phantom, and human experiments. The Inverse Laplacian method resulted in lower reconstruction bias and error due to noise in simulations than the Gaussian filter. The Inverse Laplacian method also produced conductivity maps closer to the measured values in a phantom and with reduced noise in the human brain, as compared to the Gaussian filter. The Inverse Laplacian method calculates conductivity maps with less noise and more accurate values near boundaries. Improving the accuracy of conductivity maps is integral for advancing the applications of conductivity mapping. Magn Reson Med 78:2011-2021, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Method developments approaches in supercritical fluid chromatography applied to the analysis of cosmetics.

Science.gov (United States)

Lesellier, E; Mith, D; Dubrulle, I

2015-12-04

Analyses of complex samples of cosmetics, such as creams or lotions, are generally achieved by HPLC. These analyses are often multistep gradients, due to the presence of compounds with a large range of polarity. For instance, the bioactive compounds may be polar, while the matrix contains lipid components that are rather non-polar, thus cosmetic formulations are usually oil-water emulsions. Supercritical fluid chromatography (SFC) uses mobile phases composed of carbon dioxide and organic co-solvents, allowing for good solubility of both the active compounds and the matrix excipients. Moreover, the classical and well-known properties of these mobile phases yield fast analyses and ensure rapid method development. However, due to the large number of stationary phases available for SFC and to the varied additional parameters acting both on retention and separation factors (co-solvent nature and percentage, temperature, backpressure, flow rate, column dimensions and particle size), a simplified approach can be followed to ensure a fast method development. First, suited stationary phases should be carefully selected for an initial screening, and then the other operating parameters can be limited to the co-solvent nature and percentage, maintaining the oven temperature and back-pressure constant. To describe simple method development guidelines in SFC, three sample applications are discussed in this paper: UV-filters (sunscreens) in sunscreen cream, glyceryl caprylate in eye liner and caffeine in eye serum. Firstly, five stationary phases (ACQUITY UPC(2)) are screened with isocratic elution conditions (10% methanol in carbon dioxide). Complementary of the stationary phases is assessed based on our spider diagram classification which compares a large number of stationary phases based on five molecular interactions. Secondly, the one or two best stationary phases are retained for further optimization of mobile phase composition, with isocratic elution conditions or, when

Numerical approach of multi-field two-phase flow models in the OVAP code

International Nuclear Information System (INIS)

Anela Kumbaro

2005-01-01

Full text of publication follows: A significant progress has been made in modeling the complexity of vapor-liquid two-phase flow. Different three-dimensional models exist in order to simulate the evolution of parameters which characterize a two-phase model. These models can be classified into various groups depending on the inter-field coupling. A hierarchy of increasing physical complexity can be defined. The simplest group corresponds to the homogeneous mixture models where no interactions are taken into account. Another group is constituted by the two-fluid models employing physically important interfacial forces between two-phases, liquid, and water. The last group is multi-field modeling where inter-field couplings can be taken into account at different degrees, such as the MUltiple Size Group modeling [2], the consideration of separate equations for the transport and generation of mass and momentum for each field under the assumption of the same energy for all the fields of the same phase, and a full multi-field two-phase model [1]. The numerical approach of the general three-dimensional two-phase flow is by complexity of the phenomena a very challenging task; the ideal numerical method should be at the same time simple in order to apply to any model, from equilibrium to multi-field model and conservative in order to respect the fundamental conservation physical laws. The approximate Riemann solvers have the good properties of conservation of mass, momentum and energy balance and have been extended successfully to two-fluid models [3]- [5]. But, the up-winding of the flux is based on the Eigen-decomposition of the two-phase flow model and the computation of the Eigen-structure of a multi-field model can be a high cost procedure. Our contribution will present a short review of the above two-phase models, and show numerical results obtained for some of them with an approximate Riemann solver and with lower-complexity alternative numerical methods that do not

Developing the digital literacies of academic staff: an institutional approach

Directory of Open Access Journals (Sweden)

Barbara Newland

2016-10-01

Full Text Available Institutional engagement with digital literacies at the University of Brighton has been promoted through the creation of a Digital Literacies Framework (DLF aimed at academic staff. The DLF consists of 38 literacies divided into four categories that align to the following key areas of academic work:• Learning and teaching• Research• Communication and collaboration• AdministrationFor each literacy, there is an explanation of what the literacy is, why it is important and how to gain it, with links to resources and training opportunities. After an initial pilot, the DLF website was launched in the summer of 2014. This paper discusses the strategic context and policy development of the DLF, its initial conception and subsequent development based on a pilot phase, feedback and evaluation. It critically analyses two of the ways that engagement with the DLF have been promoted: (1 formal professional development schemes and (2 the use of a ‘School-based’ approach. It examines the successes and challenges of the University of Brighton's scheme and makes some suggestions for subsequent steps including taking a course-level approach.

Sample preparation with solid phase microextraction and exhaustive extraction approaches: Comparison for challenging cases.

Science.gov (United States)

Boyacı, Ezel; Rodríguez-Lafuente, Ángel; Gorynski, Krzysztof; Mirnaghi, Fatemeh; Souza-Silva, Érica A; Hein, Dietmar; Pawliszyn, Janusz

2015-05-11

In chemical analysis, sample preparation is frequently considered the bottleneck of the entire analytical method. The success of the final method strongly depends on understanding the entire process of analysis of a particular type of analyte in a sample, namely: the physicochemical properties of the analytes (solubility, volatility, polarity etc.), the environmental conditions, and the matrix components of the sample. Various sample preparation strategies have been developed based on exhaustive or non-exhaustive extraction of analytes from matrices. Undoubtedly, amongst all sample preparation approaches, liquid extraction, including liquid-liquid (LLE) and solid phase extraction (SPE), are the most well-known, widely used, and commonly accepted methods by many international organizations and accredited laboratories. Both methods are well documented and there are many well defined procedures, which make them, at first sight, the methods of choice. However, many challenging tasks, such as complex matrix applications, on-site and in vivo applications, and determination of matrix-bound and free concentrations of analytes, are not easily attainable with these classical approaches for sample preparation. In the last two decades, the introduction of solid phase microextraction (SPME) has brought significant progress in the sample preparation area by facilitating on-site and in vivo applications, time weighted average (TWA) and instantaneous concentration determinations. Recently introduced matrix compatible coatings for SPME facilitate direct extraction from complex matrices and fill the gap in direct sampling from challenging matrices. Following introduction of SPME, numerous other microextraction approaches evolved to address limitations of the above mentioned techniques. There is not a single method that can be considered as a universal solution for sample preparation. This review aims to show the main advantages and limitations of the above mentioned sample

Preliminary Phase Field Computational Model Development

Energy Technology Data Exchange (ETDEWEB)

Li, Yulan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hu, Shenyang Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xu, Ke [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Suter, Jonathan D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McCloy, John S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Bradley R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-12-15

This interim report presents progress towards the development of meso-scale models of magnetic behavior that incorporate microstructural information. Modeling magnetic signatures in irradiated materials with complex microstructures (such as structural steels) is a significant challenge. The complexity is addressed incrementally, using the monocrystalline Fe (i.e., ferrite) film as model systems to develop and validate initial models, followed by polycrystalline Fe films, and by more complicated and representative alloys. In addition, the modeling incrementally addresses inclusion of other major phases (e.g., martensite, austenite), minor magnetic phases (e.g., carbides, FeCr precipitates), and minor nonmagnetic phases (e.g., Cu precipitates, voids). The focus of the magnetic modeling is on phase-field models. The models are based on the numerical solution to the Landau-Lifshitz-Gilbert equation. From the computational standpoint, phase-field modeling allows the simulation of large enough systems that relevant defect structures and their effects on functional properties like magnetism can be simulated. To date, two phase-field models have been generated in support of this work. First, a bulk iron model with periodic boundary conditions was generated as a proof-of-concept to investigate major loop effects of single versus polycrystalline bulk iron and effects of single non-magnetic defects. More recently, to support the experimental program herein using iron thin films, a new model was generated that uses finite boundary conditions representing surfaces and edges. This model has provided key insights into the domain structures observed in magnetic force microscopy (MFM) measurements. Simulation results for single crystal thin-film iron indicate the feasibility of the model for determining magnetic domain wall thickness and mobility in an externally applied field. Because the phase-field model dimensions are limited relative to the size of most specimens used in

Cost effective solutions for field development. System supplier approach to projects and operations

International Nuclear Information System (INIS)

Moe, P.O.

1994-01-01

The conference paper outlines the most important elements for a new approach to project realisation that enable a cost reduction of 30-50% compared to conventional methods. The achievements are based on studies and evaluations to the Norwegian Vigdis development project. The system elements covered are the electrical and automation systems including safety and process control and all traditional phases of a project from concept design to the operational phase. The concept involves new principles for project execution where traditional borderlines and interfaces between the various participants have been redefined. Management attention has been verified as an important prerequisite for a successful implementation of this strategy. 2 figs

Effective interactions approach to phase stability in alloys under irradiation

International Nuclear Information System (INIS)

Enrique, R.A.; Bellon, P.

1999-01-01

Phase stability in alloys under irradiation is studied considering effective thermodynamic potentials. A simple kinetic model of a binary alloy with phase separation is investigated. Time evolution in the alloy results form two competing dynamics: thermal diffusion, and irradiation induced ballistic exchanges. The dynamical (steady state) phase diagram is evaluated exactly performing Kinetic Monte Carlo simulations. The solution is then compared to two theoretical frameworks: the effective quasi-interactions model as proposed by Vaks and Kamishenko, and the effective free energy model as proposed by Martin. New developments of these models are proposed to allow for quantitative comparisons. Both theoretical frameworks yield fairly good approximations to the dynamical phase diagram

Effective interactions approach to phase stability in alloys under irradiation

International Nuclear Information System (INIS)

Enrique, R.A.; Bellon, P.

1999-01-01

Phase stability in alloys under irradiation is studied considering effective thermodynamic potentials. A simple kinetic model of a binary alloy with phase separation is investigated. Time evolution in the alloy results from two competing dynamics: thermal diffusion, and irradiation induced ballistic exchanges The dynamical (steady state) phase diagram is evaluated exactly performing Kinetic Monte Carlo simulations. The solution is then compared to two theoretical frameworks: the effective quasi-interactions model as proposed by Vaks and Kamishenko, and the effective free energy model as proposed by Martin. New developments of these models are proposed to allow for quantitative comparisons. Both theoretical frameworks yield fairly good approximations to the dynamical phase diagram

A rapid and rational approach to generating isomorphous heavy-atom phasing derivatives.

Science.gov (United States)

Lu, Jinghua; Sun, Peter D

2014-09-01

In attempts to replace the conventional trial-and-error heavy-atom derivative search method with a rational approach, we previously defined heavy metal compound reactivity against peptide ligands. Here, we assembled a composite pH- and buffer-dependent peptide reactivity profile for each heavy metal compound to guide rational heavy-atom derivative search. When knowledge of the best-reacting heavy-atom compound is combined with mass spectrometry assisted derivatization, and with a quick-soak method to optimize phasing, it is likely that the traditional heavy-atom compounds could meet the demand of modern high-throughput X-ray crystallography. As an example, we applied this rational heavy-atom phasing approach to determine a previously unknown mouse serum amyloid A2 crystal structure. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach)

International Nuclear Information System (INIS)

Yeh, L.

1992-01-01

The phase-space-picture approach to quantum non-equilibrium statistical mechanics via the characteristic function of infinite- mode squeezed coherent states is introduced. We use quantum Brownian motion as an example to show how this approach provides an interesting geometrical interpretation of quantum non-equilibrium phenomena

Rapid Construction of Fe-Co-Ni Composition-Phase Map by Combinatorial Materials Chip Approach.

Science.gov (United States)

Xing, Hui; Zhao, Bingbing; Wang, Yujie; Zhang, Xiaoyi; Ren, Yang; Yan, Ningning; Gao, Tieren; Li, Jindong; Zhang, Lanting; Wang, Hong

2018-03-12

One hundred nanometer thick Fe-Co-Ni material chips were prepared and isothermally annealed at 500, 600, and 700 °C, respectively. Pixel-by-pixel composition and structural mapping was performed by microbeam X-ray at synchrotron light source. Diffraction images were recorded at a rate of 1 pattern/s. The XRD patterns were automatically processed, phase-identified, and categorized by hierarchical clustering algorithm to construct the composition-phase map. The resulting maps are consistent with corresponding isothermal sections reported in the ASM Alloy Phase Diagram Database, verifying the effectiveness of the present approach in phase diagram construction.

A two-phase copula entropy-based multiobjective optimization approach to hydrometeorological gauge network design

Science.gov (United States)

Xu, Pengcheng; Wang, Dong; Singh, Vijay P.; Wang, Yuankun; Wu, Jichun; Wang, Lachun; Zou, Xinqing; Chen, Yuanfang; Chen, Xi; Liu, Jiufu; Zou, Ying; He, Ruimin

2017-12-01

Hydrometeorological data are needed for obtaining point and areal mean, quantifying the spatial variability of hydrometeorological variables, and calibration and verification of hydrometeorological models. Hydrometeorological networks are utilized to collect such data. Since data collection is expensive, it is essential to design an optimal network based on the minimal number of hydrometeorological stations in order to reduce costs. This study proposes a two-phase copula entropy- based multiobjective optimization approach that includes: (1) copula entropy-based directional information transfer (CDIT) for clustering the potential hydrometeorological gauges into several groups, and (2) multiobjective method for selecting the optimal combination of gauges for regionalized groups. Although entropy theory has been employed for network design before, the joint histogram method used for mutual information estimation has several limitations. The copula entropy-based mutual information (MI) estimation method is shown to be more effective for quantifying the uncertainty of redundant information than the joint histogram (JH) method. The effectiveness of this approach is verified by applying to one type of hydrometeorological gauge network, with the use of three model evaluation measures, including Nash-Sutcliffe Coefficient (NSC), arithmetic mean of the negative copula entropy (MNCE), and MNCE/NSC. Results indicate that the two-phase copula entropy-based multiobjective technique is capable of evaluating the performance of regional hydrometeorological networks and can enable decision makers to develop strategies for water resources management.

A New Approach to Commercialization of NASA's Human Research Program Technologies, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This Phase I SBIR proposal describes, "A New Approach to Commercialization of NASA's Human Research Program Technologies." NASA has a powerful research program that...

A quantitative benefit-risk assessment approach to improve decision making in drug development: Application of a multicriteria decision analysis model in the development of combination therapy for overactive bladder.

Science.gov (United States)

de Greef-van der Sandt, I; Newgreen, D; Schaddelee, M; Dorrepaal, C; Martina, R; Ridder, A; van Maanen, R

2016-04-01

A multicriteria decision analysis (MCDA) approach was developed and used to estimate the benefit-risk of solifenacin and mirabegron and their combination in the treatment of overactive bladder (OAB). The objectives were 1) to develop an MCDA tool to compare drug effects in OAB quantitatively, 2) to establish transparency in the evaluation of the benefit-risk profile of various dose combinations, and 3) to quantify the added value of combination use compared to monotherapies. The MCDA model was developed using efficacy, safety, and tolerability attributes and the results of a phase II factorial design combination study were evaluated. Combinations of solifenacin 5 mg and mirabegron 25 mg and mirabegron 50 (5+25 and 5+50) scored the highest clinical utility and supported combination therapy development of solifenacin and mirabegron for phase III clinical development at these dose regimens. This case study underlines the benefit of using a quantitative approach in clinical drug development programs. © 2015 The American Society for Clinical Pharmacology and Therapeutics.

Approaches for achieving broadband achromatic phase shifts for visible nulling coronagraphy

Science.gov (United States)

Bolcar, Matthew R.; Lyon, Richard G.

2012-07-01

Visible nulling coronagraphy is one of the few approaches to the direct detection and characterization of Jovian and Terrestrial exoplanets that works with segmented aperture telescopes. Jovian and Terrestrial planets require at least 10-9 and 10-10 image plane contrasts, respectively, within the spectral bandpass and thus require a nearly achromatic π-phase difference between the arms of the interferometer. An achromatic π-phase shift can be achieved by several techniques, including sequential angled thick glass plates of varying dispersive materials, distributed thin-film multilayer coatings, or techniques that leverage the polarization-dependent phase shift of total-internal reflections. Herein we describe two implementations of such techniques: sequential thick glass plates and Fresnel rhomb prisms. A viable technique must achieve the achromatic phase shift while simultaneously minimizing the intensity difference, chromatic beam spread and polarization variation between the interferometer arms. In this paper we describe the above implementations and report on the trades associated with each technique that will lead to an implementation of the most promising one in Goddard's Visible Nulling Coronagraph (VNC).

Determination of production-shipment policy using a two-phase algebraic approach

Directory of Open Access Journals (Sweden)

Huei-Hsin Chang

2012-04-01

Full Text Available The optimal production-shipment policy for end products using mathematicalmodeling and a two-phase algebraic approach is investigated. A manufacturing systemwith a random defective rate, a rework process, and multiple deliveries is studied with thepurpose of deriving the optimal replenishment lot size and shipment policy that minimisestotal production-delivery costs. The conventional method uses differential calculus on thesystem cost function to determine the economic lot size and optimal number of shipmentsfor such an integrated vendor-buyer system, whereas the proposed two-phase algebraicapproach is a straightforward method that enables practitioners who may not havesufficient knowledge of calculus to manage real-world systems more effectively.

Hanford Tank Waste Treatment and Immobilization Plant (WTP) Waste Feed Qualification Program Development Approach - 13114

Energy Technology Data Exchange (ETDEWEB)

Markillie, Jeffrey R.; Arakali, Aruna V.; Benson, Peter A.; Halverson, Thomas G. [Hanford Tank Waste Treatment and Immobilization Plant Project, Richland, WA 99354 (United States); Adamson, Duane J.; Herman, Connie C.; Peeler, David K. [Savannah River National Laboratory, Aiken, SC 29808 (United States)

2013-07-01

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is a nuclear waste treatment facility being designed and constructed for the U.S. Department of Energy by Bechtel National, Inc. and subcontractor URS Corporation (under contract DE-AC27-01RV14136 [1]) to process and vitrify radioactive waste that is currently stored in underground tanks at the Hanford Site. A wide range of planning is in progress to prepare for safe start-up, commissioning, and operation. The waste feed qualification program is being developed to protect the WTP design, safety basis, and technical basis by assuring acceptance requirements can be met before the transfer of waste. The WTP Project has partnered with Savannah River National Laboratory to develop the waste feed qualification program. The results of waste feed qualification activities will be implemented using a batch processing methodology, and will establish an acceptable range of operator controllable parameters needed to treat the staged waste. Waste feed qualification program development is being implemented in three separate phases. Phase 1 required identification of analytical methods and gaps. This activity has been completed, and provides the foundation for a technically defensible approach for waste feed qualification. Phase 2 of the program development is in progress. The activities in this phase include the closure of analytical methodology gaps identified during Phase 1, design and fabrication of laboratory-scale test apparatus, and determination of the waste feed qualification sample volume. Phase 3 will demonstrate waste feed qualification testing in support of Cold Commissioning. (authors)

Frequency Preference Response to Oscillatory Inputs in Two-dimensional Neural Models: A Geometric Approach to Subthreshold Amplitude and Phase Resonance.

Science.gov (United States)

Rotstein, Horacio G

2014-01-01

We investigate the dynamic mechanisms of generation of subthreshold and phase resonance in two-dimensional linear and linearized biophysical (conductance-based) models, and we extend our analysis to account for the effect of simple, but not necessarily weak, types of nonlinearities. Subthreshold resonance refers to the ability of neurons to exhibit a peak in their voltage amplitude response to oscillatory input currents at a preferred non-zero (resonant) frequency. Phase-resonance refers to the ability of neurons to exhibit a zero-phase (or zero-phase-shift) response to oscillatory input currents at a non-zero (phase-resonant) frequency. We adapt the classical phase-plane analysis approach to account for the dynamic effects of oscillatory inputs and develop a tool, the envelope-plane diagrams, that captures the role that conductances and time scales play in amplifying the voltage response at the resonant frequency band as compared to smaller and larger frequencies. We use envelope-plane diagrams in our analysis. We explain why the resonance phenomena do not necessarily arise from the presence of imaginary eigenvalues at rest, but rather they emerge from the interplay of the intrinsic and input time scales. We further explain why an increase in the time-scale separation causes an amplification of the voltage response in addition to shifting the resonant and phase-resonant frequencies. This is of fundamental importance for neural models since neurons typically exhibit a strong separation of time scales. We extend this approach to explain the effects of nonlinearities on both resonance and phase-resonance. We demonstrate that nonlinearities in the voltage equation cause amplifications of the voltage response and shifts in the resonant and phase-resonant frequencies that are not predicted by the corresponding linearized model. The differences between the nonlinear response and the linear prediction increase with increasing levels of the time scale separation between

Laser-induced microstructural development and phase evolution in magnesium alloy

International Nuclear Information System (INIS)

Guan, Y.C.; Zhou, W.; Li, Z.L.; Zheng, H.Y.

2014-01-01

Highlights: • Secondary phase evolution caused by laser processing was firstly reported. • Microstructure development was controlled by heat flow thermodynamics and kinetics. • Solid-state transformation resulted in submicron and nano-scale precipitates. • Cluster-shaped particles in overlapped region were due to precipitation coarsening. • Properties of materials can be tailored selectively by laser processing. -- Abstract: Secondary phase plays an important role in determining microstructures and properties of magnesium alloys. This paper focuses on laser-induced microstructure development and secondary phase evolution in AZ91D Mg alloy studied by SEM, TEM and EDS analyses. Compared to bulk shape and lamellar structure of the secondary phase in as-received cast material, rapid-solidified microstructures with various morphologies including nano-precipitates were observed in laser melt zone. Formation mechanisms of microstructural evolution and effect of phase development on surface properties were further discussed

Innovative approaches to clinical development and trial design

Directory of Open Access Journals (Sweden)

John J Orloff

2011-01-01

Full Text Available Pharmaceutical innovation is increasingly risky, costly and at times inefficient, which has led to a decline in industry productivity. Despite the increased investment in R&D by the industry, the number of new molecular entities achieving marketing authorization is not increasing. Novel approaches to clinical development and trial design could have a key role in overcoming some of these challenges by improving efficiency and reducing attrition rates. The effectiveness of clinical development can be improved by adopting a more integrated model that increases flexibility and maximizes the use of accumulated knowledge. Central to this model of drug development are novel tools, including modelling and simulation, Bayesian methodologies, and adaptive designs, such as seamless adaptive designs and sample-size re-estimation methods. Applications of these methodologies to early- and late-stage drug development are described with some specific examples, along with advantages, challenges, and barriers to implementation. Because they are so flexible, these new trial designs require significant statistical analyses, simulations and logistical considerations to verify their operating characteristics, and therefore tend to require more time for the planning and protocol development phase. Greater awareness of the distinct advantages of innovative designs by regulators and sponsors are crucial to increasing the adoption of these modern tools.

A phase field approach for multicellular aggregate fusion in biofabrication.

Science.gov (United States)

Yang, Xiaofeng; Sun, Yi; Wang, Qi

2013-07-01

We present a modeling and computational approach to study fusion of multicellular aggregates during tissue and organ fabrication, which forms the foundation for the scaffold-less biofabrication of tissues and organs known as bioprinting. It is known as the phase field method, where multicellular aggregates are modeled as mixtures of multiphase complex fluids whose phase mixing or separation is governed by interphase force interactions, mimicking the cell-cell interaction in the multicellular aggregates, and intermediate range interaction mediated by the surrounding hydrogel. The material transport in the mixture is dictated by hydrodynamics as well as forces due to the interphase interactions. In a multicellular aggregate system with fixed number of cells and fixed amount of the hydrogel medium, the effect of cell differentiation, proliferation, and death are neglected in the current model, which can be readily included in the model, and the interaction between different components is dictated by the interaction energy between cell and cell as well as between cell and medium particles, respectively. The modeling approach is applicable to transient simulations of fusion of cellular aggregate systems at the time and length scale appropriate to biofabrication. Numerical experiments are presented to demonstrate fusion and cell sorting during tissue and organ maturation processes in biofabrication.

Adjusting for Misclassification: A Three-Phase Sampling Approach

Directory of Open Access Journals (Sweden)

Sang Hailin

2017-03-01

Full Text Available The United States Department of Agriculture’s National Agricultural Statistics Service (NASS conducts the June Agricultural Survey (JAS annually. Substantial misclassification occurs during the prescreening process and from field-estimating farm status for nonresponse and inaccessible records, resulting in a biased estimate of the number of US farms from the JAS. Here, the Annual Land Utilization Survey (ALUS is proposed as a follow-on survey to the JAS to adjust the estimates of the number of US farms and other important variables. A three-phase survey design-based estimator is developed for the JAS-ALUS with nonresponse adjustment for the second phase (ALUS. A design-unbiased estimator of the variance is provided in explicit form.

A standardized approach to verification and validation to assist in expert system development

International Nuclear Information System (INIS)

Hines, J.W.; Hajek, B.K.; Miller, D.W.; Haas, M.A.

1992-01-01

For the past six years, the Nuclear Engineering Program's Artificial Intelligence (AI) Group at The Ohio State University has been developing an integration of expert systems to act as an aid to nuclear power plant operators. This Operator Advisor consists of four modules that monitor plant parameters, detect deviations from normality, diagnose the root cause of the abnormality, manage procedures to effectively respond to the abnormality, and mitigate its consequences. To aid in the development of this new system, a standardized Verification and Validation (V and V) approach is being implemented. The primary functions are to guide the development of the expert system and to ensure that the end product fulfills the initial objectives. The development process has been divided into eight life-cycle V and V phases from concept to operation and maintenance. Each phase has specific V and V tasks to be performed to ensure a quality end product. Four documents are being used to guide development. The Software Verification and Validation Plan (SVVP) outlines the V and V tasks necessary to verify the product at the end of each software development phase, and to validate that the end product complies with the established software and system requirements and meets the needs of the user. The Software Requirements Specification (SRS) documents the essential requirements of the system. The Software Design Description (SDD) represents these requirements with a specific design. And lastly, the Software Test Document establishes a testing methodology to be used throughout the development life-cycle

The active phasing experiment: Part II. Design and developments

Science.gov (United States)

Gonte, F.; Yaitskova, N.; Derie, F.; Araujo, C.; Brast, R.; Delabre, B.; Dierickx, P.; Dupuy, C.; Frank, C.; Guisard, S.; Karban, R.; Noethe, L.; Sedghi, B.; Surdej, I.; Wilhelm, R.; Reyes, M.; Esposito, S.; Langlois, M.

2006-06-01

The purpose of the Active Phasing Experiment, designed under the lead of ESO, is to validate wavefront control concepts for ELT class telescopes. This instrument includes an Active Segmented Mirror, located in a pupil image. It will be mounted at a Nasmyth focus of one of the Unit Telescopes of the ESO VLT. APE contains four different types of phasing sensors, which are developed by Istituto Nazionale di Astrofisica in Arcetri, Instituto Astrofisica Canarias, Laboratoire d'Astrophysique de Marseille and ESO. These phasing sensors can be compared simultaneously under identical optical and environmental conditions. All sensors receive telecentric F/15 beams with identical optical quality and intensity. Each phasing sensor can measure segmentation errors of the active segmented mirror and correct them in closed loop. The phasing process is supervised by an Internal Metrology system developed by FOGALE Nanotech and capable of measuring piston steps with an accuracy of a few nanometers. The Active Phasing Experiment is equipped with a turbulence generator to simulate atmospheric seeing between 0.45 and 0.85 arcsec in the laboratory. In addition, the Active Phasing Experiment is designed to control simultaneously with the phasing corrections the guiding and the active optics of one of the VLT Unit Telescopes. This activity is supported by the European Community (Framework Programme 6, ELT Design Study, contract No 011863).

Semiclassical moment of inertia shell-structure within the phase-space approach

International Nuclear Information System (INIS)

Gorpinchenko, D V; Magner, A G; Bartel, J; Blocki, J P

2015-01-01

The moment of inertia for nuclear collective rotations is derived within a semiclassical approach based on the cranking model and the Strutinsky shell-correction method by using the non-perturbative periodic-orbit theory in the phase-space variables. This moment of inertia for adiabatic (statistical-equilibrium) rotations can be approximated by the generalized rigid-body moment of inertia accounting for the shell corrections of the particle density. A semiclassical phase-space trace formula allows us to express the shell components of the moment of inertia quite accurately in terms of the free-energy shell corrections for integrable and partially chaotic Fermi systems, which is in good agreement with the corresponding quantum calculations. (paper)

Development of a Novel, Bicombinatorial Approach to Alloy Development, and Application to Rapid Screening of Creep Resistant Titanium Alloys

Science.gov (United States)

Martin, Brian

Combinatorial approaches have proven useful for rapid alloy fabrication and optimization. A new method of producing controlled isothermal gradients using the Gleeble Thermomechanical simulator has been developed, and demonstrated on the metastable beta-Ti alloy beta-21S, achieving a thermal gradient of 525-700 °C. This thermal gradient method has subsequently been coupled with existing combinatorial methods of producing composition gradients using the LENS(TM) additive manufacturing system, through the use of elemental blended powders. This has been demonstrated with a binary Ti-(0-15) wt% Cr build, which has subsequently been characterized with optical and electron microscopy, with special attention to the precipitate of TiCr2 Laves phases. The TiCr2 phase has been explored for its high temperature mechanical properties in a new oxidation resistant beta-Ti alloy, which serves as a demonstration of the new bicombinatorial methods developed as applied to a multicomponent alloy system.

Modeling of microstructure evolution in direct metal laser sintering: A phase field approach

Science.gov (United States)

Nandy, Jyotirmoy; Sarangi, Hrushikesh; Sahoo, Seshadev

2017-02-01

Direct Metal Laser Sintering (DMLS) is a new technology in the field of additive manufacturing, which builds metal parts in a layer by layer fashion directly from the powder bed. The process occurs within a very short time period with rapid solidification rate. Slight variations in the process parameters may cause enormous change in the final build parts. The physical and mechanical properties of the final build parts are dependent on the solidification rate which directly affects the microstructure of the material. Thus, the evolving of microstructure plays a vital role in the process parameters optimization. Nowadays, the increase in computational power allows for direct simulations of microstructures during materials processing for specific manufacturing conditions. In this study, modeling of microstructure evolution of Al-Si-10Mg powder in DMLS process was carried out by using a phase field approach. A MATLAB code was developed to solve the set of phase field equations, where simulation parameters include temperature gradient, laser scan speed and laser power. The effects of temperature gradient on microstructure evolution were studied and found that with increase in temperature gradient, the dendritic tip grows at a faster rate.

Preparation of CdS microtrumpets from a solvent extraction system by a two-phase approach

International Nuclear Information System (INIS)

Geng, Aifang; Liu, Yubing; Liao, Wuping

2011-01-01

Highlights: → CdS microtrumpets were prepared from an extraction system by a two-phase approach. → Triethanolamine plays a crucial role in the formation of the trumpets. → Some micro-lotus seedpods can also be obtained with trihydroxymethyl aminomethane. -- Abstract: CdS microtrumpets with the length being of about 4 μm and the bell wall being of 100 nm have been prepared using a cadmium di-(2-ethylhexyl) phosphoric acid chelate as the precursor by a two-phase thermal approach. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The effects of temperature, reaction time, and co-surfactant on the morphology were also examined. It was found that the co-surfactant triethanolamine plays a crucial role in the formation of the cubic phase trumpet-like CdS microstructures.

Multi-phase classification by a least-squares support vector machine approach in tomography images of geological samples

Science.gov (United States)

Khan, Faisal; Enzmann, Frieder; Kersten, Michael

2016-03-01

Image processing of X-ray-computed polychromatic cone-beam micro-tomography (μXCT) data of geological samples mainly involves artefact reduction and phase segmentation. For the former, the main beam-hardening (BH) artefact is removed by applying a best-fit quadratic surface algorithm to a given image data set (reconstructed slice), which minimizes the BH offsets of the attenuation data points from that surface. A Matlab code for this approach is provided in the Appendix. The final BH-corrected image is extracted from the residual data or from the difference between the surface elevation values and the original grey-scale values. For the segmentation, we propose a novel least-squares support vector machine (LS-SVM, an algorithm for pixel-based multi-phase classification) approach. A receiver operating characteristic (ROC) analysis was performed on BH-corrected and uncorrected samples to show that BH correction is in fact an important prerequisite for accurate multi-phase classification. The combination of the two approaches was thus used to classify successfully three different more or less complex multi-phase rock core samples.

Anatase-rutile phase transformation of titanium dioxide bulk material: a DFT + U approach

International Nuclear Information System (INIS)

Vu, Nam H; Le, Hieu V; Cao, Thi M; Pham, Viet V; Le, Hung M; Nguyen-Manh, Duc

2012-01-01

The anatase-rutile phase transformation of TiO 2 bulk material is investigated using a density functional theory (DFT) approach in this study. According to the calculations employing the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional with the Vanderbilt ultrasoft pseudopotential, it is suggested that the anatase phase is more energetically stable than rutile, which is in variance with the experimental observations. Consequently, the DFT + U method is employed in order to predict the correct structural stability in titania from electronic-structure-based total energy calculations. The Hubbard U term is determined by examining the band structure of rutile with various values of U from 3 to 10 eV. At U = 5 eV, a theoretical bandgap for rutile is obtained as 3.12 eV, which is in very good agreement with the reported experimental bandgap. Hence, we choose the DFT + U method (with U = 5 eV) to investigate the transformation pathway using the newly-developed solid-state nudged elastic band (ss-NEB) method, and consequently obtain an intermediate transition structure that is 9.794 eV per four-TiO 2 above the anatase phase. When the Ti-O bonds in the transition state are examined using charge density analysis, seven Ti-O bonds (out of 24 bonds in the anatase unit cell) are broken, and this result is in excellent agreement with a previous experimental study (Penn and Banfield 1999 Am. Miner. 84 871-6).

SWR 1000 approaching bidding phase status

International Nuclear Information System (INIS)

Brettschuh, W.; Meseth, J.

2000-01-01

The SWR 1000 is an advanced version of the previous 69 and 72 lines by Siemens/KWU. Like its predecesor, the SWR 600, this development project is handled by Siemens on behalf of German utilities, and supported by various European partners contributing engineering and experimental work. With its electric power of approx. 1000 MW, the SWR 1000 differs from earlier KWU boiling water reactor designs especially in having several passive safety systems in addition to some of the active systems customarily used in earlier plants. In a postulated failure of the active safety systems, the passive safety systems can completely take over their function. The passive safety systems are characterized by not needing any external power supply after having been activated, and by not requiring initiation by the I and C system to be activated. In addition, plant operating systems were streamlined, always subject to the guiding principle to employ, as far as possible, technical components and systems with proven operating records. In late 1999, the basic design phase in the development of the SWR 1000 was completed in which all newly designed components and systems as well as those modified greatly over existing BWR plants, including electrical and I and C systems, were designed and the main buildings, such as the reactor building, turbine hall, auxiliary and utilities building, were planned. All newly designed components, systems, and processes were successfully tested for their functioning capability and capacity in large scale tests. The results of the basic design phase were compiled in a site independent safety report based on the rules and regulations applicable in Germany. (orig.) [de

An Easy Approach to Control β-Phase Formation in PFO Films for Optimized Emission Properties

Directory of Open Access Journals (Sweden)

Qi Zhang

2017-02-01

Full Text Available We demonstrate a novel approach to control β-phase content generated in poly(9,9-dioctylfluorene (PFO films. A very small amount of paraffin oil was used as the additive to the PFO solution in toluene. The β-phase fraction in the spin-coated PFO films can be modified from 0% to 20% simply by changing the volume percentage of paraffin oil in the mixed solution. Organic light emitting diodes (OLEDs and amplified spontaneous emission (ASE study confirmed low β-phase fraction promise better OLEDs device, while high β-phase fraction benefits ASE performance.

Collaborative development of the EPICS Qt framework Phase I Final Report

Energy Technology Data Exchange (ETDEWEB)

Mayssat, Robert E. [Lyncean Technologies, Inc., Palo Alto, CA (United States)

2015-01-15

At Lyncean, a private company spun-off from technology developed at the SLAC National Lab, we have been using EPICS for over a decade. EPICS is ubiquitous on our flagship product – the Compact Light Source. EPICS is not only used to control our laser and accelerator systems, but also to control our x-ray beamlines. The goal of this SBIR is for Lyncean Technologies to spearhead a worldwide collaborative effort for the development of control system tools for EPICS using the Qt framework, a C++-based coding environment that could serve as a competitive alternative to the Java-based Control System Studio (CSS). This grant's Phase I, not unlike a feasibility study, is designed for planning and scoping the preparatory work needed for Phase II or other funding opportunities. The three main objectives of this Phase I are (1) to become better acquainted with the existing EPICS Qt software and Qt framework in order to evaluate the best options for ongoing development, (2) to demonstrate that our engineers can lead the EPICS community and jump-start the Qt collaboration, and (3) to identify a scope for our future work with solicited feedback from the EPICS community. This Phase I report includes key technical findings. It clarifies the differences between the two apparently-competing EPICS Qt implementations, caQtDM and the QE Framework; it explains how to create python-bindings, and compares Qt graphical libraries. But this report is also a personal story that narrates the birth of a collaboration. Starting a collaboration is not the work of a single individual, but the work of many. Therefore this report is also an attempt to publicly give credit to many who supported the effort. The main take-away from this grant is the successful birth of an EPICS Qt collaboration, seeded with existing software from the PSI and the Australian Synchrotron. But a lot more needs to be done for the collaboration founders' vision to be realized, and for the collaboration to reach

A phenomenological approach of solidification of polymeric phase change materials

Science.gov (United States)

Bahrani, Seyed Amir; Royon, Laurent; Abou, Bérengère; Osipian, Rémy; Azzouz, Kamel; Bontemps, André

2017-01-01

Phase Change Materials (PCMs) are widely used in thermal energy storage and thermal management systems due to their small volume for a given stored energy and their capability for maintaining nearly constant temperatures. However, their performance is limited by their low thermal conductivity and possible leaks while in the liquid phase. One solution is to imprison the PCM inside a polymer mesh to create a Polymeric Phase Change Material (PPCM). In this work, we have studied the cooling and solidification of five PPCMs with different PCMs and polymer fractions. To understand the heat transfer mechanisms involved, we have carried out micro- and macrorheological measurements in which Brownian motion of tracers embedded in PPCMs has been depicted and viscoelastic moduli have been measured, respectively. Beyond a given polymer concentration, it was shown that the Brownian motion of the tracers is limited by the polymeric chains and that the material exhibits an elastic behavior. This would suggest that heat transfer essentially occurs by conduction, instead of convection. Experiments were conducted to measure temperature variation during cooling of the five samples, and a semi-empirical model based on a phenomenological approach was proposed as a practical tool to choose and size PPCMs.

Application of the Double-Tangent Construction of Coexisting Phases to Any Type of Phase Equilibrium for Binary Systems Modeled with the Gamma-Phi Approach

Science.gov (United States)

Jaubert, Jean-Noël; Privat, Romain

2014-01-01

The double-tangent construction of coexisting phases is an elegant approach to visualize all the multiphase binary systems that satisfy the equality of chemical potentials and to select the stable state. In this paper, we show how to perform the double-tangent construction of coexisting phases for binary systems modeled with the gamma-phi…

Development of optical phase shifter based on piezoelectric ceramic

Science.gov (United States)

Yu, Fusheng; Shen, Xiaoqin; Yao, Chunjuan; Leng, Changlin

2005-02-01

The phase shifter is necessary in the optical phase-shifting measurement. At present the phase shifter commonly used is approximately divided into the penetrance-type and the reflection-type. In this paper, a reflection-type phase shifter made of piezoelectric ceramic stackup assemble is developed. The assemble are constituted of the flat piezoelectric ceramic with parallel connection circuit and inline structure. The communication between the computer and MCU is by RS232. The D/A converter controlled by the MCU outputs 0~10V voltage. Then the voltage is amplified to 0~400V DC voltage by the designed linear DC amplifier. When this voltage loads on the piezoelectric ceramic stackup assemble, the assemble will axially extend 0~5mm. In this paper, the connecting types for the mechanical construction and circuit of the piezoelectric ceramic stackup assemble, the driving power and the DC amplifier with high linearity are all introduced. The whole system developed is standardized by using phase-interfering Michelson. The standardization and the practical application indicates that this system has excellent linearity and precision repeatability.

NIMROD: A Customer Focused, Team Driven Approach for Fusion Code Development

Science.gov (United States)

Karandikar, H. M.; Schnack, D. D.

1996-11-01

NIMROD is a new code that will be used for the analysis of existing fusion experiments, prediction of operational limits, and design of future devices. An approach called Integrated Product Development (IPD) is being used for the development of NIMROD. It is a dramatic departure from existing practice in the fusion program. Code development is being done by a self-directed, multi-disciplinary, multi-institutional team that consists of experts in plasma theory, experiment, computational physics, and computer science. Customer representatives (ITER, US experiments) are an integral part of the team. The team is using techniques such as Quality Function Deployment (QFD), Pugh Concept Selection, Rapid Prototyping, and Risk Management, during the design phase of NIMROD. Extensive use is made of communication and internet technology to support collaborative work. Our experience with using these team techniques for such a complex software development project will be reported.

Modeling of annular two-phase flow using a unified CFD approach

Energy Technology Data Exchange (ETDEWEB)

Li, Haipeng, E-mail: haipengl@kth.se; Anglart, Henryk, E-mail: henryk@kth.se

2016-07-15

Highlights: • Annular two-phase flow has been modeled using a unified CFD approach. • Liquid film was modeled based on a two-dimensional thin film assumption. • Both Eulerian and Lagrangian methods were employed for the gas core flow modeling. - Abstract: A mechanistic model of annular flow with evaporating liquid film has been developed using computational fluid dynamics (CFD). The model is employing a separate solver with two-dimensional conservation equations to predict propagation of a thin boiling liquid film on solid walls. The liquid film model is coupled to a solver of three-dimensional conservation equations describing the gas core, which is assumed to contain a saturated mixture of vapor and liquid droplets. Both the Eulerian–Eulerian and the Eulerian–Lagrangian approach are used to describe the droplet and vapor motion in the gas core. All the major interaction phenomena between the liquid film and the gas core flow have been accounted for, including the liquid film evaporation as well as the droplet deposition and entrainment. The resultant unified framework for annular flow has been applied to the steam-water flow with conditions typical for a Boiling Water Reactor (BWR). The simulation results for the liquid film flow rate show good agreement with the experimental data, with the potential to predict the dryout occurrence based on criteria of critical film thickness or critical film flow rate.

Modeling of annular two-phase flow using a unified CFD approach

International Nuclear Information System (INIS)

Li, Haipeng; Anglart, Henryk

2016-01-01

Highlights: • Annular two-phase flow has been modeled using a unified CFD approach. • Liquid film was modeled based on a two-dimensional thin film assumption. • Both Eulerian and Lagrangian methods were employed for the gas core flow modeling. - Abstract: A mechanistic model of annular flow with evaporating liquid film has been developed using computational fluid dynamics (CFD). The model is employing a separate solver with two-dimensional conservation equations to predict propagation of a thin boiling liquid film on solid walls. The liquid film model is coupled to a solver of three-dimensional conservation equations describing the gas core, which is assumed to contain a saturated mixture of vapor and liquid droplets. Both the Eulerian–Eulerian and the Eulerian–Lagrangian approach are used to describe the droplet and vapor motion in the gas core. All the major interaction phenomena between the liquid film and the gas core flow have been accounted for, including the liquid film evaporation as well as the droplet deposition and entrainment. The resultant unified framework for annular flow has been applied to the steam-water flow with conditions typical for a Boiling Water Reactor (BWR). The simulation results for the liquid film flow rate show good agreement with the experimental data, with the potential to predict the dryout occurrence based on criteria of critical film thickness or critical film flow rate.

New developments for determination of uncertainty in phase evaluation

Science.gov (United States)

Liu, Sheng

Phase evaluation exists mostly in, but not limited to, interferometric applications that utilize coherent multidimensional signals to modulate the physical quantity of interest into a nonlinear form, represented by repeating the phase modulo of 271 radians. In order to estimate the underlying physical quantity, the wrapped phase has to be unwrapped by an evaluation procedure which is usually called phase unwrapping. The procedure of phase unwrapping will obviously face the challenge of inconsistent phase, which could bring errors in phase evaluation. The main objectives of this research include addressing the problem of inconsistent phase in phase unwrapping and applications in modern optical techniques. In this research, a new phase unwrapping algorithm is developed. The creative idea of doing phase unwrapping between regions has an advantage over conventional pixel-to-pixel unwrapping methods because the unwrapping result is more consistent by using a voting mechanism based on all Zit-discontinuities hints. Furthermore, a systematic sequence of regional unwrapping is constructed in order to achieve a global consistent result. An implementation of the idea is illustrated in dct.il with step-by-step pseudo codes. The performance of the algorithm is demonstrated on real world applications. In order to solve a phase unwrapping problem which is caused by depth discontinuities in 3D shape measurement, a new absolute phase coding strategy is developed. The algorithm presented has two merits: effectively extends the coding range and preserves the measurement sensitivity. The performance of the proposed absolute coding strategy is proved by results of 3D shape measurement for objects with surface discontinuities. As a powerful tool for real world applications a universal software package, Optical Measurement and Evaluation Software (OMES), is designed for the purposes of automatic measurement and quantitative evaluation in 3D shape measurement and laser interferometry

GREECE FACES A YIN-YANG DEVELOPMENT PHASE

Directory of Open Access Journals (Sweden)

Stefania Andra SIMIONESCU

2015-09-01

Full Text Available The concept Yin-Yang represents the unity of opposites and complementarity. In this respect, from the economical point of view a positive Yin phase represents the cash flow, brings nutrition, gentleness and protection, while a negative Yin phase means capital loss, sloth and passive obedience, a positive Yang phase is translated as an action based on funds, emphasising the creation, the construction and the development of infrastructure thanks to an economical action plan, while a negative Yang phase leads to conflicts, to excessive product stocks and to a stock market collapse, causing, in this line, crisis and inflation by increasing prices and decreasing purchasing power. In the European Union, Greece faces a Yang negative phase. When having too much positive Yin monetary stimulus from the EU, the Yin-Yang balance turns in favour of a negative Yang bankrupcy and unemployment. Thus, I explore not only the Greece’s economical dimension, but also its geographic role, the synergy between culture and DNA and the last, but not the least, the human’s ability in creating a new positive Yin-Yang flourishing future.

Service design as an approach to new service development : reflections and futures studies

OpenAIRE

Yu, Eun; Sangiorgi, Daniela

2014-01-01

This paper illustrates how, although Service Design has been described as evolving from a narrow description of a phase in New Service Development (NSD) to an approach to Service Innovation, the current Service Design research is still focused on the initial stages of NSD. Comparing existing Service Design research with foundational knowledge on NSD, the authors have proposed two complementary directions for future Service Design studies: 1) the expansion of ‘service design as a phase’ to inv...

A Regional Approach to Wildlife Monitoring Related to Energy Exploration and Development in Colorado

Science.gov (United States)

Kotliar, Natasha B.; Bowen, Zachary H.; Ouren, Douglas S.; Farmer, Adrian H.

2008-01-01

: White River, Glenwood Springs, Kremmling, Grand Junction, and Little Snake. The overall study area was selected to encompass the primary distribution of sagebrush and greater sage-grouse (Centrocercus urophasianus) in Colorado and to provide a larger context for evaluating priority management issues of the White River and Glenwood Springs Field Offices. Within the study area, we selected an additional scale of analysis: the Roan Plateau, an area of increased energy development. We focused our demonstration project on the primary objectives identified by the BLM and other stakeholders: (1) How do we evaluate the cumulative effects of energy development and mitigation activities on species of management interest or concern? (2) How can cumulative effects, including direct and indirect effects, be quantified relative to natural variation? (3) How can we implement compliance and effectiveness monitoring to determine whether lease stipulations are met and restoration/mitigation goals are achieved? We targeted greater sage-grouse because this species was identified as a monitoring priority for the White River Field Office. We also evaluated landscape-level indices to address fragmentation resulting from surface disturbance. The primary purpose of this exercise was to highlight the types of analyses and approaches that could be used to evaluate energy development in an application of the three-phase framework. We provide examples of Phase I products that can be used to guide the refinement of management objectives, development of adaptive management and research frameworks, and planning activities in Phase II. Finally, we report on the BLM's National Sage-Grouse Habitat Conservation Strategy as an example of Phase III activities. The development of an effective monitoring program is a daunting task, and will be difficult to implement by the BLM independently due to the current work load of staff. However, the scientific expertise and experience for developing cr

A similarity score-based two-phase heuristic approach to solve the dynamic cellular facility layout for manufacturing systems

Science.gov (United States)

Kumar, Ravi; Singh, Surya Prakash

2017-11-01

The dynamic cellular facility layout problem (DCFLP) is a well-known NP-hard problem. It has been estimated that the efficient design of DCFLP reduces the manufacturing cost of products by maintaining the minimum material flow among all machines in all cells, as the material flow contributes around 10-30% of the total product cost. However, being NP hard, solving the DCFLP optimally is very difficult in reasonable time. Therefore, this article proposes a novel similarity score-based two-phase heuristic approach to solve the DCFLP optimally considering multiple products in multiple times to be manufactured in the manufacturing layout. In the first phase of the proposed heuristic, a machine-cell cluster is created based on similarity scores between machines. This is provided as an input to the second phase to minimize inter/intracell material handling costs and rearrangement costs over the entire planning period. The solution methodology of the proposed approach is demonstrated. To show the efficiency of the two-phase heuristic approach, 21 instances are generated and solved using the optimization software package LINGO. The results show that the proposed approach can optimally solve the DCFLP in reasonable time.

MECHANICAL CHARACTERISTICS OF THREE-PHASE INDUCTION MOTORS WITH SINGLE-PHASE POWER SUPPLY

Directory of Open Access Journals (Sweden)

V.S. Malyar

2016-06-01

Full Text Available Aim. Development of a method for calculating mechanical characteristics of three-phase induction motors with single-phase power supply. Methods. The developed algorithm is based on the high-adequacy mathematical model of motor and projection method for solving the boundary problem for equations of electrical circuits balance presented in the three-phase coordinate system. As a result of asymmetry of power supply to the stator windings, in steady state, flux-linkage and current change according to the periodic law. They are determined by solving the boundary problem. Results. The developed mathematical model allows determining periodic dependence of coordinates as a function of slip and, based on them, mechanical characteristics of motors. Academic novelty. The developed method relies on a completely new mathematical approach to calculation of stationary modes of nonlinear electromagnetic circuits, which allows obtaining periodic solution in a timeless domain. Practical value. Using the developed calculation algorithm, one can select capacitance required to start an induction motor with single-phase power supply and calculate static mechanical characteristics at a given capacitance.

Braze Development of Graphite Fiber for Use in Phase Change Material Heat Sinks

Science.gov (United States)

Quinn, Gregory; Beringer, Woody; Gleason, Brian; Stephan, Ryan

2011-01-01

Hamilton Sundstrand (HS), together with NASA Johnson Space Center, developed methods to metallurgically join graphite fiber to aluminum. The goal of the effort was to demonstrate improved thermal conductance, tensile strength and manufacturability compared to existing epoxy bonded techniques. These improvements have the potential to increase the performance and robustness of phase change material heat sinks that use graphite fibers as an interstitial material. Initial work focused on evaluating joining techniques from four suppliers, each consisting of a metallization step followed by brazing or soldering of one inch square blocks of Fibercore graphite fiber material to aluminum end sheets. Results matched the strength and thermal conductance of the epoxy bonded control samples, so two suppliers were down-selected for a second round of braze development. The second round of braze samples had up to a 300% increase in strength and up to a 132% increase in thermal conductance over the bonded samples. However, scalability and repeatability proved to be significant hurdles with the metallization approach. An alternative approach was pursued which used a nickel braze allow to prepare the carbon fibers for joining with aluminum. Initial results on sample blocks indicate that this approach should be repeatable and scalable with good strength and thermal conductance when compared with epoxy bonding.

Wind Turbine Drivetrain Condition Monitoring During GRC Phase 1 and Phase 2 Testing

Energy Technology Data Exchange (ETDEWEB)

Sheng, S.; Link, H.; LaCava, W.; van Dam, J.; McNiff, B.; Veers, P.; Keller, J.; Butterfield, S.; Oyague, F.

2011-10-01

This report will present the wind turbine drivetrain condition monitoring (CM) research conducted under the phase 1 and phase 2 Gearbox Reliability Collaborative (GRC) tests. The rationale and approach for this drivetrain CM research, investigated CM systems, test configuration and results, and a discussion on challenges in wind turbine drivetrain CM and future research and development areas, will be presented.

An in situ vapour phase hydrothermal surface doping approach for fabrication of high performance Co3O4 electrocatalysts with an exceptionally high S-doped active surface.

Science.gov (United States)

Tan, Zhijin; Liu, Porun; Zhang, Haimin; Wang, Yun; Al-Mamun, Mohammad; Yang, Hua Gui; Wang, Dan; Tang, Zhiyong; Zhao, Huijun

2015-04-04

A facile in situ vapour phase hydrothermal (VPH) surface doping approach has been developed for fabrication of high performance S-doped Co3O4 electrocatalysts with an unprecedentedly high surface S content (>47%). The demonstrated VPH doping approach could be useful for enrichment of surface active sites for other metal oxide electrocatalysts.

Developing a framework for assessing the impact of geothermal development phases on ecosystem services

Science.gov (United States)

Semedi, Jarot M.; Willemen, Louise; Nurlambang, Triarko; van der Meer, Freek; Koestoer, Raldi H.

2017-12-01

The 2014 Indonesian National Energy Policy has set a target to provide national primary energy usage reached 2.500 kWh per capita in the year 2025 and reached 7.000 kWh in the year 2050. The National Energy Policy state that the development of energy should consider the balance of energy economic values, energy supply security, and the conservation of the environment. This has led to the prioritization of renewable energy sources. Geothermal energy a renewable energy source that produces low carbon emissions and is widely available in Indonesia due to the country’s location in the “volcanic arc”. The development of geothermal energy faces several problems related to its potential locations in Indonesia. The potential sites for geothermal energy are mostly located in the volcanic landscapes that have a high hazard risk and are often designated protected areas. Local community low knowledge of geothermal use also a challenge for geothermal development where sometimes strong local culture stand in the way. Each phase of geothermal energy development (exploration, construction, operation and maintenance, and decommissioning) will have an impact on the landscape and everyone living in it. Meanwhile, natural and other human-induced drivers will keep landscapes and environments changing. This conference paper addresses the development of an integrated assessment to spatially measure the impact of geothermal energy development phases on ecosystem services. Listing the effects on the ecosystem services induced by each geothermal development phases and estimating the spatial impact using Geographic Information System (GIS) will result in an overview on where and how much each geothermal development phase affects the ecosystem and how this information could be included to improve national spatial planning.

The partnership approach to siting and developing radioactive waste management facilities

International Nuclear Information System (INIS)

2010-03-01

History shows that the search for sites for radioactive waste management facilities has been marred by conflicts and delays. Affected communities have often objected that their concerns and interests were not addressed. In response, institutions have progressively turned away from the traditional 'decide, announce and defend' model, and are learning to 'engage, interact and co-operate'. This shift has fostered the emergence of partnerships between the proponent of the facility and the potential host community. Working in partnership with potential host communities enables pertinent issues and concerns to be raised and addressed, and creates an opportunity for developing a relationship of mutual understanding and mutual learning, as well as for developing solutions that will add value to the host community and region. Key elements of the partnership approach are being incorporated into waste management strategies, leading increasingly to positive outcomes. National radioactive waste management programmes are in various phases of siting facilities and rely on different technical approaches for the various categories of waste. In all cases, it is necessary for institutional actors and the potential or actual host community to build a meaningful, workable relationship. Partnership approaches are effective in achieving a desirable combination of licensable site and management concept while meeting the sometimes competing requirements of fair representation and competent participation. Partnership arrangements facilitate reaching agreement on measures for local control, financial support and future development

An Overview of 2014 SBIR Phase 1 and Phase 2 Communications Technology and Development

Science.gov (United States)

Nguyen, Hung D.; Steele, Gynelle C.; Morris, Jessica R.

2015-01-01

NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights eight of the innovative SBIR 2014 Phase I and Phase II projects that emphasize one of NASA Glenn Research Center's six core competencies-Communication Technology and Development. The technologies cover a wide spectrum of applications such as X-ray navigation, microsensor instrument for unmanned aerial vehicle airborne atmospheric measurements, 16-element graphene-based phased array antenna system, interferometric star tracker, ultralow power fast-response sensor, and integrated spacecraft navigation and communication. Each featured technology describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report provides an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.

A platform analytical quality by design (AQbD) approach for multiple UHPLC-UV and UHPLC-MS methods development for protein analysis.

Science.gov (United States)

Kochling, Jianmei; Wu, Wei; Hua, Yimin; Guan, Qian; Castaneda-Merced, Juan

2016-06-05

A platform analytical quality by design approach for methods development is presented in this paper. This approach is not limited just to method development following the same logical Analytical quality by design (AQbD) process, it is also exploited across a range of applications in methods development with commonality in equipment and procedures. As demonstrated by the development process of 3 methods, the systematic approach strategy offers a thorough understanding of the method scientific strength. The knowledge gained from the UHPLC-UV peptide mapping method can be easily transferred to the UHPLC-MS oxidation method and the UHPLC-UV C-terminal heterogeneity methods of the same protein. In addition, the platform AQbD method development strategy ensures method robustness is built in during development. In early phases, a good method can generate reliable data for product development allowing confident decision making. Methods generated following the AQbD approach have great potential for avoiding extensive post-approval analytical method change. While in the commercial phase, high quality data ensures timely data release, reduced regulatory risk, and lowered lab operational cost. Moreover, large, reliable database and knowledge gained during AQbD method development provide strong justifications during regulatory filling for the selection of important parameters or parameter change needs for method validation, and help to justify for removal of unnecessary tests used for product specifications. Copyright © 2016 Elsevier B.V. All rights reserved.

Guiding Development Based Approach Practicum Vertebrates Taxonomy Scientific Study Program for Students of Biology Education

Science.gov (United States)

Arieska, M.; Syamsurizal, S.; Sumarmin, R.

2018-04-01

Students having difficulty in identifying and describing the vertebrate animals as well as less skilled in science process as practical. Increased expertise in scientific skills, one of which is through practical activities using practical guidance based on scientific approach. This study aims to produce practical guidance vertebrate taxonomy for biology education students PGRI STKIP West Sumatra valid. This study uses a model of Plomp development consisting of three phases: the initial investigation, floating or prototype stage, and the stage of assessment. Data collection instruments used in this study is a validation sheet guiding practicum. Data were analyzed descriptively based on data obtained from the field. The result of the development of practical guidance vertebrate taxonomic validity value of 3.22 is obtained with very valid category. Research and development has produced a practical guide based vertebrate taxonomic scientific approach very valid.

Phase reconstruction from velocity-encoded MRI measurements – A survey of sparsity-promoting variational approaches

KAUST Repository

Benning, Martin

2014-01-01

In recent years there has been significant developments in the reconstruction of magnetic resonance velocity images from sub-sampled k-space data. While showing a strong improvement in reconstruction quality compared to classical approaches, the vast number of different methods, and the challenges in setting them up, often leaves the user with the difficult task of choosing the correct approach, or more importantly, not selecting a poor approach. In this paper, we survey variational approaches for the reconstruction of phase-encoded magnetic resonance velocity images from sub-sampled k-space data. We are particularly interested in regularisers that correctly treat both smooth and geometric features of the image. These features are common to velocity imaging, where the flow field will be smooth but interfaces between the fluid and surrounding material will be sharp, but are challenging to represent sparsely. As an example we demonstrate the variational approaches on velocity imaging of water flowing through a packed bed of solid particles. We evaluate Wavelet regularisation against Total Variation and the relatively recent second order Total Generalised Variation regularisation. We combine these regularisation schemes with a contrast enhancement approach called Bregman iteration. We verify for a variety of sampling patterns that Morozov\\'s discrepancy principle provides a good criterion for stopping the iterations. Therefore, given only the noise level, we present a robust guideline for setting up a variational reconstruction scheme for MR velocity imaging. © 2013 Elsevier Inc. All rights reserved.

Design and Development of a compact and ruggest phase and flouresence microscope for space utilization, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — In this SBIR Phase 1 we propose to develop a novel microscope by integrating Fourier phase contrast microscopy (FPCM) and epi-fluorescence microscopy. In FPCM, the...

Classification of Global Land Development Phases by Forest and GDP Changes for Appropriate Land Management in the Mid-Latitude

Directory of Open Access Journals (Sweden)

Cholho Song

2017-08-01

Full Text Available To implement appropriate land management strategies, it is essential to identify past and current land cover and land use conditions. In addition, an assessment of land development phases (LDPs in a human-dominated landscape coupled with an analysis of the water-food-ecosystem (WFE nexus can deepen our understanding of sustainable land management. In this study, we proposed the concept of land development phases (LDPs by forest and GDP changes using previously-applied theoretical and empirical approaches. The positive relationship between GDP growth and forest stock changes was used to analyze the timing of forest stock changes as five-year averages, which were aggregated over 20 years to classify LDPs. In addition, forest area changes compared with GDP and GDP per capita changes were analyzed to identify LDPs. Based on two conceptual approaches, we suggested global land into three LDPs: degradation, restoration and sustainability. Using this approach, most of Europe, North America and northeast Asia were classified as sustainability phases, while Africa and Central Asia in the Mid-Latitude region appeared to have degradation or restoration phases. The LDPs described could be improved with further incorporation of solid data analysis and clear standards, but even at this stage, these LDP classifications suggest points for implementing appropriate land management. In addition, indices from comparative analysis of the LDPs with the WFE nexus can be connected with socio-economic global indices, such as the Global Hunger Index, the Food Production Index and the Climate Change Performance Index. The LDPs have the potential to facilitate appropriate land management strategies through integrating WFE nexus and ecosystem services; we propose future research that uses this integration for the Mid-Latitude region and worldwide.

Tourism and Cultural Heritage: Higher Education and Entrepreneurship Development in Transition Phase. The Tunisian Experience

Directory of Open Access Journals (Sweden)

Faysal Mansouri

2014-10-01

Full Text Available This is to lay down an approach to develop tourism and cultural heritage through higher education and entrepreneurship development for economies in transition: The case of Tunisia. There is a need to provide incentives to people to have favorable preferences toward a tourism based in part on cultural heritage in a phase where everything is being under construction institutions, legislations, and relationships alike. Cultural heritage and tourism development may be enhanced by a diversification strategy to enrich the image of local touristic destinations (diversification of site visits, purchases of new products, new circuits, and discovery of monumental heritage, museum, park and gardens, natural sites. Moreover, it is of great importance to invest in youth entrepreneurship development to orient toward business creation and development in the domain of tourism and cultural heritage.

Quantum scaling in many-body systems an approach to quantum phase transitions

CERN Document Server

Continentino, Mucio

2017-01-01

Quantum phase transitions are strongly relevant in a number of fields, ranging from condensed matter to cold atom physics and quantum field theory. This book, now in its second edition, approaches the problem of quantum phase transitions from a new and unifying perspective. Topics addressed include the concepts of scale and time invariance and their significance for quantum criticality, as well as brand new chapters on superfluid and superconductor quantum critical points, and quantum first order transitions. The renormalisation group in real and momentum space is also established as the proper language to describe the behaviour of systems close to a quantum phase transition. These phenomena introduce a number of theoretical challenges which are of major importance for driving new experiments. Being strongly motivated and oriented towards understanding experimental results, this is an excellent text for graduates, as well as theorists, experimentalists and those with an interest in quantum criticality.

TTI Phase 2 Institutional Support: Sustainable Development Policy ...

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

TTI Phase 2 Institutional Support: Sustainable Development Policy Institute. This funding will strengthen the Sustainable Development Policy Institute's (SDPI) role as a credible public policy institution in Pakistan by enhancing its ability to provide high-quality, influential, and policy-relevant research. About the Sustainable ...

The System-Synergetic Approach to Development of Banking Systems under Conditions of Financial Instability

Directory of Open Access Journals (Sweden)

Karcheva Ganna T.

2015-03-01

Full Text Available The aim of the article is to study the theoretical and practical aspects of using the system-synergetic approach to the development and functioning of banking systems under conditions of financial instability. It has been grounded that the theoretical foundations for the development of banking systems are based on the system approach, according to which the banking systems belong to a class of special complex dynamic, self-motivated and open systems with an integrated structure of subsystems and functions. The study of such systems should include two aspects — system-cybernetic and system-synergetic ones. It has been proved that under stationary conditions the banking system development goes on in accordance with the systemcybernetic model, which suggests the presence of a management subsystem, which functions are performed by the central bank. Under conditions of financial instability, in the pre-crisis, crisis and post-crisis periods to study the development of banking systems the system-synergetic approach taking into account the multi-variant and alternative development of the banking system at bifurcation points is used. The criteria of the banking system entering the phase of bifurcation based on assessing the volatility of the current liabilities and possibility of building an analytical trend have been determined. The methodical approaches to evaluating the synergistic effects and level of financial stability of the banking system have been suggested, experimental calculations have been made.

A standardized approach to verification and validation to assist in expert system development

International Nuclear Information System (INIS)

Hines, J.W.; Hajek, B.K.; Miller, D.W.; Haas, M.A.

1992-01-01

For the past six years, the Nuclear Engineering Program's Artificial Intelligence (AI) Group at The Ohio State University has been developing an integration of expert systems to act as an aid to nuclear power plant operators. This Operator Advisor consists of four modules that monitor plant parameters, detect deviations from normality, diagnose the root cause of the abnormality, manage procedures to effectively respond to the abnormality, and mitigate its consequences. Recently Ohio State University received a grant from the Department of Energy's Special Research Grant Program to utilize the methodologies developed for the Operator Advisor for Heavy Water Reactor (HWR) malfunction root cause diagnosis. To aid in the development of this new system, a standardized Verification and Validation (V ampersand V) approach is being implemented. Its primary functions are to guide the development of the expert system and to ensure that the end product fulfills the initial objectives. The development process has been divided into eight life-cycle V ampersand V phases from concept to operation and maintenance. Each phase has specific V ampersand V tasks to be performed to ensure a quality end product. Four documents are being used to guide development. The Software Verification and Validation Plan (SVVP) outlines the V ampersand V tasks necessary to verify the product at the end of each software development phase, and to validate that the end product complies with the established software and system requirements and meets the needs of the user. The Software Requirements Specification (SRS) documents the essential requirements of the system. The Software Design Description (SDD) represents these requirements with a specific design. And lastly, the Software Test Document establishes a testing methodology to be used throughout the development life-cycle. 10 refs., 1 fig

Damage development, phase changes, transport properties, and freeze-thaw performance of cementitious materials exposed to chloride based salts

Science.gov (United States)

Farnam, Yaghoob

Recently, there has been a dramatic increase in premature deterioration in concrete pavements and flat works that are exposed to chloride based salts. Chloride based salts can cause damage and deterioration in concrete due to the combination of factors which include: increased saturation, ice formation, salt crystallization, osmotic pressure, corrosion in steel reinforcement, and/or deleterious chemical reactions. This thesis discusses how chloride based salts interact with cementitious materials to (1) develop damage in concrete, (2) create new chemical phases in concrete, (3) alter transport properties of concrete, and (4) change the concrete freeze-thaw performance. A longitudinal guarded comparative calorimeter (LGCC) was developed to simultaneously measure heat flow, damage development, and phase changes in mortar samples exposed to sodium chloride (NaCl), calcium chloride (CaCl 2), and magnesium chloride (MgCl2) under thermal cycling. Acoustic emission and electrical resistivity measurements were used in conjunction with the LGCC to assess damage development and electrical response of mortar samples during cooling and heating. A low-temperature differential scanning calorimetry (LT-DSC) was used to evaluate the chemical interaction that occurs between the constituents of cementitious materials (i.e., pore solution, calcium hydroxide, and hydrated cement paste) and salts. Salts were observed to alter the classical phase diagram for a salt-water system which has been conventionally used to interpret the freeze-thaw behavior in concrete. An additional chemical phase change was observed for a concrete-salt-water system resulting in severe damage in cementitious materials. In a cementitious system exposed to NaCl, the chemical phase change occurs at a temperature range between -6 °C and 8 °C due to the presence of calcium sulfoaluminate phases in concrete. As a result, concrete exposed to NaCl can experience additional freeze-thaw cycles due to the chemical

Safety critical software design approach developed for Canadian nuclear power plants

International Nuclear Information System (INIS)

Ichiyen, M.M.; Joannou, P.K.

1995-01-01

Recently two methodologies were developed that comply with a high safety critical standard: the Rational Design Process, which can be characterized as a methodology based on state machines where the required behaviour of the software is defined using mathematical functions written in a notation which has a well defined syntax and semantics, and the Integrated Approach, which uses a graphical functional notation to specify the functional software requirements. The first implementations based on the two methodologies are discussed. Results from all phases of testing show a remarkably low number of errors, demonstrating that the new methodologies have indeed led to a higher demonstrable level of software reliability. (orig./HP) [de

An Open-Loop Grid Synchronization Approach for Single-Phase Applications

DEFF Research Database (Denmark)

Golestan, Saeed; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

2018-01-01

in the presence of frequency drifts. This is particularly true in single-phase applications, where the lack of multiple independent input signals makes the implementation of the synchronization technique difficult. The aim of this paper is to develop an effective OLS technique for single-phase power and energy...... applications. The proposed OLS method benefits from a straightforward implementation, a fast dynamic response (a response time less than two cycles of the nominal frequency), and a complete immunity against the DC component in the grid voltage. In addition, the designed OLS method totally blocks (significantly...

Application of Precipitate Free Zone Growth Kinetics to the β-Phase Depletion Behavior in a CoNiCrAlY Coating Alloy: An Analytical Approach

Science.gov (United States)

Chen, H.

2018-06-01

This paper concerns the β-phase depletion kinetics of a thermally sprayed free-standing CoNiCrAlY (Co-31.7 pct Ni-20.8 pct Cr-8.1 pct Al-0.5 pct Y, all in wt pct) coating alloy. An analytical β-phase depletion model based on the precipitate free zone growth kinetics was developed to calculate the β-phase depletion kinetics during isothermal oxidation. This approach, which accounts for the molar volume of the alloy, the interfacial energy of the γ/ β interface, and the Al concentration at γ/ γ + β boundary, requires the Al concentrations in the β-phase depletion zone as the input rather than the oxidation kinetics at the oxide/coating interface. The calculated β-phase depletion zones derived from the current model were compared with experimental results. It is shown that the calculated β-phase depletion zones using the current model are in reasonable agreement with those obtained experimentally. The constant compositional terms used in the model are likely to cause the discrepancies between the model predictions and experimental results. This analytical approach, which shows a reasonable correlation with experimental results, demonstrates a good reliability in the fast evaluation on lifetime prediction of MCrAlY coatings.

Application of Precipitate Free Zone Growth Kinetics to the β-Phase Depletion Behavior in a CoNiCrAlY Coating Alloy: An Analytical Approach

Science.gov (United States)

Chen, H.

2018-03-01

This paper concerns the β-phase depletion kinetics of a thermally sprayed free-standing CoNiCrAlY (Co-31.7 pct Ni-20.8 pct Cr-8.1 pct Al-0.5 pct Y, all in wt pct) coating alloy. An analytical β-phase depletion model based on the precipitate free zone growth kinetics was developed to calculate the β-phase depletion kinetics during isothermal oxidation. This approach, which accounts for the molar volume of the alloy, the interfacial energy of the γ/β interface, and the Al concentration at γ/γ + β boundary, requires the Al concentrations in the β-phase depletion zone as the input rather than the oxidation kinetics at the oxide/coating interface. The calculated β-phase depletion zones derived from the current model were compared with experimental results. It is shown that the calculated β-phase depletion zones using the current model are in reasonable agreement with those obtained experimentally. The constant compositional terms used in the model are likely to cause the discrepancies between the model predictions and experimental results. This analytical approach, which shows a reasonable correlation with experimental results, demonstrates a good reliability in the fast evaluation on lifetime prediction of MCrAlY coatings.

Space nuclear power plant technology development philosophy for a ground engineering phase

International Nuclear Information System (INIS)

Buden, D.; Trapp, T.J.; Los Alamos National Lab., NM)

1985-01-01

The development of a space qualified nuclear power plant is proceeding from the technical assessment and advancement phase to the ground engineering phase. In this new phase, the selected concept will be matured by the completion of activities needed before protoflight units can be assembled and qualified for first flight applications. This paper addresses a possible philosophy to arrive at the activities to be performed during the ground engineering phase. The philosophy is derived from what we believe a potential user of nuclear power would like to see completed before commitment to a flight development phase. 5 references

Space nuclear power plant technology development philosophy for a ground engineering phase

International Nuclear Information System (INIS)

Buden, D.; Trapp, T.J.

1985-01-01

The development of a space qualified nuclear power plant is proceeding from the Technical Assessment and Advancement Phase to the Ground Engineering Phase. In this new phase, the selected concept will be matured by the completion of activities needed before protoflight units can be assembled and qualified for first flight applications. This paper addresses a possible philosophy to arrive at the activities to be performed during the Ground Engineering Phase. The philosophy is derived from what we believe a potential user of nuclear power would like to see completed before commitment to a flight development phase

An integrated systems-based approach to mercury research and technology development

Energy Technology Data Exchange (ETDEWEB)

Peterson, Mark J [ORNL; Brooks, Scott C [ORNL; Mathews, Teresa J [ORNL; Mayes, Melanie [ORNL; Watson, David B [ORNL; Johs, Alexander [ORNL; Mehlhorn, Tonia L [ORNL; Dickson, Johnbull O [ORNL; Mansfield, Charles [East Tennessee Technology Park (ETTP); Phillips, Elizabeth [U.S. Department of Energy (DOE); Pierce, Eric M [ORNL

2017-01-01

A 3-year strategic planning process was undertaken in Oak Ridge, Tennessee, to develop a research and technology development approach that can help guide mercury remediation in East Fork Poplar Creek (EFPC). Mercury remediation is a high priority for the US Department of Energy s (DOE s) Oak Ridge Office of Environmental Management because of large historical losses of mercury to the environment at the Y-12 National Security Complex (Y-12). Because of the extent of mercury losses and the complexities of mercury transport and fate in the stream environment, the success of conventional options for mercury remediation in the downstream sections of EFPC is uncertain. The overall Oak Ridge mercury remediation strategy focuses on mercury treatment actions at Y-12 in the short-term and research and technology development to evaluate longer-term solutions in the downstream environment. The technology development strategy is consistent with a phased, adaptive management paradigm and DOE s Technology Readiness Level guidelines. That is, early evaluation includes literature review, site characterization, and small-scale studies of a broad number of potential technologies. As more information is gathered, technologies that may have the most promise and potential remediation benefit will be chosen for more extensive and larger-scale pilot testing before being considered for remedial implementation. Field and laboratory research in EFPC is providing an improved level of understanding of mercury transport and fate processes in EFPC that will inform the development of site-specific remedial technologies. Technology development has centered on developing strategies that can mitigate the primary factors affecting mercury risks in the stream: (1) the amount of inorganic mercury available to the stream system, (2) the conversion of inorganic mercury to methylmercury, and (3) the bioaccumulation of methylmercury through the food web. Given the downstream complexities and

Microgrid Design, Development and Demonstration - Final Report for Phase I and Phase II

Energy Technology Data Exchange (ETDEWEB)

Bose, Sumit [GE Global Research Center, Niskayuna, NY (United States); Krok, Michael [GE Global Research Center, Niskayuna, NY (United States)

2011-02-08

This document constitutes GE’s final report for the Microgrid Design, Development and Demonstration program for DOE’s Office of Electricity Delivery and Energy Reliability, Award DE-FC02-05CH11349. It contains the final report for Phase I in Appendix I, and the results the work performed in Phase II. The program goal was to develop and demonstrate a Microgrid Energy Management (MEM) framework for a broad set of Microgrid applications that provides unified controls, protection, and energy management. This project contributed to the achievement of the U.S. Department of Energy’s Renewable and Distributed Systems Integration Program goals by developing a fully automated power delivery microgrid network that: - Reduces carbon emissions and emissions of other air pollutants through increased use of optimally dispatched renewable energy, - Increases asset use through integration of distributed systems, - Enhances reliability, security, and resiliency from microgrid applications in critical infrastructure protection, constrained areas of the electric grid, etc. - Improves system efficiency with on-site, distributed generation and improved economic efficiency through demand-side management.

Applying innovative approach “Nature of Science (NoS) within inquiry” for developing scientific literacy in the student worksheet

Science.gov (United States)

Widowati, A.; Anjarsari, P.; Zuhdan, K. P.; Dita, A.

2018-03-01

The challenges of the 21st century require innovative solutions. Education must able to make an understanding of science learning that leads to the formation of scientific literacy learners. This research was conducted to produce the prototype as science worksheet based on Nature of Science (NoS) within inquiry approach and to know the effectiveness its product for developing scientific literacy. This research was the development and research design, by pointing to Four D models and Borg & Gall Model. There were 4 main phases (define, design, develop, disseminate) and additional phases (preliminary field testing, main product revision, main field testing, and operational product revision). Research subjects were students of the junior high school in Yogyakarta. The instruments used included questionnaire sheet product validation and scientific literacy test. For the validation data were analyzed descriptively. The test result was analyzed by an N-gain score. The results showed that the appropriateness of worksheet applying NoS within inquiry-based learning approach is eligible based on the assessment from excellent by experts and teachers, students’ scientific literacy can improve high category of the N-gain score at 0.71 by using student worksheet with Nature of Science (NoS) within inquiry approach.

A Bayesian approach to degradation-based burn-in optimization for display products exhibiting two-phase degradation patterns

International Nuclear Information System (INIS)

Yuan, Tao; Bae, Suk Joo; Zhu, Xiaoyan

2016-01-01

Motivated by the two-phase degradation phenomena observed in light displays (e.g., plasma display panels (PDPs), organic light emitting diodes (OLEDs)), this study proposes a new degradation-based burn-in testing plan for display products exhibiting two-phase degradation patterns. The primary focus of the burn-in test in this study is to eliminate the initial rapid degradation phase, while the major purpose of traditional burn-in tests is to detect and eliminate early failures from weak units. A hierarchical Bayesian bi-exponential model is used to capture two-phase degradation patterns of the burn-in population. Mission reliability and total cost are introduced as planning criteria. The proposed burn-in approach accounts for unit-to-unit variability within the burn-in population, and uncertainty concerning the model parameters, mainly in the hierarchical Bayesian framework. Available pre-burn-in data is conveniently incorporated into the burn-in decision-making procedure. A practical example of PDP degradation data is used to illustrate the proposed methodology. The proposed method is compared to other approaches such as the maximum likelihood method or the change-point regression. - Highlights: • We propose a degradation-based burn-in test for products with two-phase degradation. • Mission reliability and total cost are used as planning criteria. • The proposed burn-in approach is built within the hierarchical Bayesian framework. • A practical example was used to illustrate the proposed methodology.

An approach for upgrading biomass and pyrolysis product quality using a combination of aqueous phase bio-oil washing and torrefaction pretreatment.

Science.gov (United States)

Chen, Dengyu; Cen, Kehui; Jing, Xichun; Gao, Jinghui; Li, Chen; Ma, Zhongqing

2017-06-01

Bio-oil undergoes phase separation because of poor stability. Practical application of aqueous phase bio-oil is challenging. In this study, a novel approach that combines aqueous phase bio-oil washing and torrefaction pretreatment was used to upgrade the biomass and pyrolysis product quality. The effects of individual and combined pretreatments on cotton stalk pyrolysis were studied using TG-FTIR and a fixed bed reactor. The results showed that the aqueous phase bio-oil washing pretreatment removed metals and resolved the two pyrolysis peaks in the DTG curve. Importantly, it increased the bio-oil yield and improved the pyrolysis product quality. For example, the water and acid content of bio-oil decreased significantly along with an increase in phenol formation, and the heating value of non-condensable gases improved, and these were more pronounced when combined with torrefaction pretreatment. Therefore, the combined pretreatment is a promising method, which would contribute to the development of polygeneration pyrolysis technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

A complementary mobile phase approach based on the peak count concept oriented to the full resolution of complex mixtures.

Science.gov (United States)

Ortín, A; Torres-Lapasió, J R; García-Álvarez-Coque, M C

2011-08-26

Situations of minimal resolution are often found in liquid chromatography, when samples that contain a large number of compounds, or highly similar in terms of structure and/or polarity, are analysed. This makes full resolution with a single separation condition (e.g., mobile phase, gradient or column) unfeasible. In this work, the optimisation of the resolution of such samples in reversed-phase liquid chromatography is approached using two or more isocratic mobile phases with a complementary resolution behaviour (complementary mobile phases, CMPs). Each mobile phase is dedicated to the separation of a group of compounds. The CMPs are selected in such a way that, when the separation is considered globally, all the compounds in the sample are satisfactorily resolved. The search of optimal CMPs can be carried out through a comprehensive examination of the mobile phases in a selected domain. The computation time of this search has been reported to be substantially reduced by application of a genetic algorithm with local search (LOGA). A much simpler approach is here described, which is accessible to non-experts in programming, and offers solutions of the same quality as LOGA, with a similar computation time. The approach makes a sequential search of CMPs based on the peak count concept, which is the number of peaks exceeding a pre-established resolution threshold. The new approach is described using as test sample a mixture of 30 probe compounds, 23 of them with an ionisable character, and the pH and organic solvent contents as experimental factors. Copyright © 2011 Elsevier B.V. All rights reserved.

On the Use of Hybrid Development Approaches in Software and Systems Development

DEFF Research Database (Denmark)

Kuhrmann, Marco; Münch, Jürgen; Diebold, Philipp

2016-01-01

A software process is the game plan to organize project teams and run projects. Yet, it still is a challenge to select the appropriate development approach for the respective context. A multitude of development approaches compete for the users’ favor, but there is no silver bullet serving all...... possible setups. Moreover, recent research as well as experience from practice shows companies utilizing different development approaches to assemble the best-fitting approach for the respective company: a more traditional process provides the basic framework to serve the organization, while project teams...

Phased Array Antenna Testbed Development at the NASA Glenn Research Center

Science.gov (United States)

Lambert, Kevin M.; Kubat, Gregory; Johnson, Sandra K.; Anzic, Godfrey

2003-01-01

Ideal phased array antennas offer advantages for communication systems, such as wide-angle scanning and multibeam operation, which can be utilized in certain NASA applications. However, physically realizable, electronically steered, phased array antennas introduce additional system performance parameters, which must be included in the evaluation of the system. The NASA Glenn Research Center (GRC) is currently conducting research to identify these parameters and to develop the tools necessary to measure them. One of these tools is a testbed where phased array antennas may be operated in an environment that simulates their use. This paper describes the development of the testbed and its use in characterizing a particular K-Band, phased array antenna.

Development of One Dimensional Hyperbolic Coupled Solver for Two-Phase Flows

International Nuclear Information System (INIS)

Kim, Eoi Jin; Kim, Jong Tae; Jeong, Jae June

2008-08-01

The purpose of this study is a code development for one dimensional two-phase two-fluid flows. In this study, the computations of two-phase flow were performed by using the Roe scheme which is one of the upwind schemes. The upwind scheme is widely used in the computational fluid dynamics because it can capture discontinuities clearly such as a shock. And this scheme is applicable to multi-phase flows by the extension methods which were developed by Toumi, Stadtke, etc. In this study, the extended Roe upwind scheme by Toumi for two-phase flow was implemented in the one-dimensional code. The scheme was applied to a shock tube problem and a water faucet problem. This numerical method seems efficient for non oscillating solutions of two phase flow problems, and also capable for capturing discontinuities

Development of One Dimensional Hyperbolic Coupled Solver for Two-Phase Flows

Energy Technology Data Exchange (ETDEWEB)

Kim, Eoi Jin; Kim, Jong Tae; Jeong, Jae June

2008-08-15

The purpose of this study is a code development for one dimensional two-phase two-fluid flows. In this study, the computations of two-phase flow were performed by using the Roe scheme which is one of the upwind schemes. The upwind scheme is widely used in the computational fluid dynamics because it can capture discontinuities clearly such as a shock. And this scheme is applicable to multi-phase flows by the extension methods which were developed by Toumi, Stadtke, etc. In this study, the extended Roe upwind scheme by Toumi for two-phase flow was implemented in the one-dimensional code. The scheme was applied to a shock tube problem and a water faucet problem. This numerical method seems efficient for non oscillating solutions of two phase flow problems, and also capable for capturing discontinuities.

Identifying Effective Design Approaches to Allocate Genotypes in Two-Phase Designs: A Case Study in Pelargonium zonale

Directory of Open Access Journals (Sweden)

Heike Molenaar

2018-01-01

Full Text Available Robust phenotypic data allow adequate statistical analysis and are crucial for any breeding purpose. Such data is obtained from experiments laid out to best control local variation. Additionally, experiments frequently involve two phases, each contributing environmental sources of variation. For example, in a former experiment we conducted to evaluate production related traits in Pelargonium zonale, there were two consecutive phases, each performed in a different greenhouse. Phase one involved the propagation of the breeding strains to obtain the stem cutting count, and phase two involved the assessment of root formation. The evaluation of the former study raised questions regarding options for improving the experimental layout: (i Is there a disadvantage to using exactly the same design in both phases? (ii Instead of generating a separate layout for each phase, can the design be optimized across both phases, such that the mean variance of a pair-wise treatment difference (MVD can be decreased? To answer these questions, alternative approaches were explored to generate two-phase designs either in phase-wise order (Option 1 or across phases (Option 2. In Option 1 we considered the scenarios (i using in both phases the same experimental design and (ii randomizing each phase separately. In Option 2, we considered the scenarios (iii generating a single design with eight replicates and splitting these among the two phases, (iv separating the block structure across phases by dummy coding, and (v design generation with optimal alignment of block units in the two phases. In both options, we considered the same or different block structures in each phase. The designs were evaluated by the MVD obtained by the intra-block analysis and the joint inter-block–intra-block analysis. The smallest MVD was most frequently obtained for designs generated across phases rather than for each phase separately, in particular when both phases of the design were

Identifying Effective Design Approaches to Allocate Genotypes in Two-Phase Designs: A Case Study in Pelargonium zonale.

Science.gov (United States)

Molenaar, Heike; Boehm, Robert; Piepho, Hans-Peter

2017-01-01

Robust phenotypic data allow adequate statistical analysis and are crucial for any breeding purpose. Such data is obtained from experiments laid out to best control local variation. Additionally, experiments frequently involve two phases, each contributing environmental sources of variation. For example, in a former experiment we conducted to evaluate production related traits in Pelargonium zonale , there were two consecutive phases, each performed in a different greenhouse. Phase one involved the propagation of the breeding strains to obtain the stem cutting count, and phase two involved the assessment of root formation. The evaluation of the former study raised questions regarding options for improving the experimental layout: (i) Is there a disadvantage to using exactly the same design in both phases? (ii) Instead of generating a separate layout for each phase, can the design be optimized across both phases, such that the mean variance of a pair-wise treatment difference (MVD) can be decreased? To answer these questions, alternative approaches were explored to generate two-phase designs either in phase-wise order (Option 1) or across phases (Option 2). In Option 1 we considered the scenarios (i) using in both phases the same experimental design and (ii) randomizing each phase separately. In Option 2, we considered the scenarios (iii) generating a single design with eight replicates and splitting these among the two phases, (iv) separating the block structure across phases by dummy coding, and (v) design generation with optimal alignment of block units in the two phases. In both options, we considered the same or different block structures in each phase. The designs were evaluated by the MVD obtained by the intra-block analysis and the joint inter-block-intra-block analysis. The smallest MVD was most frequently obtained for designs generated across phases rather than for each phase separately, in particular when both phases of the design were separated with a

Perception approaches and practices of local farming and development: an anthropological approach

International Nuclear Information System (INIS)

Hadi, S.A.; Chaudhry, A.G.

2015-01-01

The study focused on recognizing the local approaches of farming in designing and implementation of development projects. These approaches are representative of a particular ecological, social, economical, and political system, shaped by the constraints and opportunities associated to the area. Effective and successful development projects must include the local perceptions, their approaches and practices, as the locals are the ones most representative of their issues and have the most workable solution to them. The traditional agriculture has completely been clutched into the nexus of modern farming methods, due to which they are being abandoned by the farmers. Modern farming which is representative of development has increased the competition, transitioning, breaking the community into people experimenting on modern technology and those who are still finding means to adapt their traditional agriculture to the fast changing needs of the societies. The research was carried out in the villages of Ghora Gali and Aruka through qualitative and quantitative methods. Sustainable development in Pakistan thus needs to be reinvented in the local perspective considering approaches and practices and, eradicating the alien chains of development completely. (author)

Cluster Mean-Field Approach to the Steady-State Phase Diagram of Dissipative Spin Systems

Directory of Open Access Journals (Sweden)

Jiasen Jin

2016-07-01

Full Text Available We show that short-range correlations have a dramatic impact on the steady-state phase diagram of quantum driven-dissipative systems. This effect, never observed in equilibrium, follows from the fact that ordering in the steady state is of dynamical origin, and is established only at very long times, whereas in thermodynamic equilibrium it arises from the properties of the (free energy. To this end, by combining the cluster methods extensively used in equilibrium phase transitions to quantum trajectories and tensor-network techniques, we extend them to nonequilibrium phase transitions in dissipative many-body systems. We analyze in detail a model of spin-1/2 on a lattice interacting through an XYZ Hamiltonian, each of them coupled to an independent environment that induces incoherent spin flips. In the steady-state phase diagram derived from our cluster approach, the location of the phase boundaries and even its topology radically change, introducing reentrance of the paramagnetic phase as compared to the single-site mean field where correlations are neglected. Furthermore, a stability analysis of the cluster mean field indicates a susceptibility towards a possible incommensurate ordering, not present if short-range correlations are ignored.

Developing an energy design tool: Phase 1 report

Energy Technology Data Exchange (ETDEWEB)

Heidell, J.A.; Deringer, J.D.

1987-02-01

This report documents the planning phase of a proposed four-phase project for creating computer software to provide energy expertise in a manageable form to architects and engineers - thereby decreasing energy use in new buildings. The government sponsored software would be integrated with commercially developed software for use in the design of buildings. The result would be an integrated software package to aid the designer in the building design process and to provide expert insight into the energy related implications of a proposed design.

A methodological approach for the identification of arsenic bearing phases in polluted soils

International Nuclear Information System (INIS)

Matera, V.; Le Hecho, I.; Laboudigue, A.; Thomas, P.; Tellier, S.; Astruc, M.

2003-01-01

Arsenic in the three polluted soils is mainly associated with neoformed amorphous iron (hydr)oxides. - A methodological approach is used to characterize arsenic pollution in three soils and to determine arsenic speciation and association with solid phases in three polluted soils. HPLC-ICP-MS was used for arsenic speciation analysis, SEM-EDS and XRD for physical characterization of arsenic pollution, and sequential chemical extractions to identify arsenic distribution. Arsenic was concentrated in the finest size fractions also enriched in iron and aluminium. Total arsenic concentrations in soils are close to 1%. Arsenic was mainly present as arsenate, representing more than 90% of total arsenic. No crystallised arsenic minerals were detected by XRD analysis. SEM-EDS observations indicated arsenic/iron associations. Modified Tessier's procedure showed that arsenic was mainly extracted from amorphous iron oxide phase. The results of this methodological approach lead to predict the formation of iron arsenates in the case of one of the studied soils while arsenic sorption on iron amorphous (hydr)oxides seemed to be the determinant in the two other soils

Top-Down and Bottom-Up Approaches in Engineering 1 T Phase Molybdenum Disulfide (MoS2 ): Towards Highly Catalytically Active Materials.

Science.gov (United States)

Chua, Chun Kiang; Loo, Adeline Huiling; Pumera, Martin

2016-09-26

The metallic 1 T phase of MoS2 has been widely identified to be responsible for the improved performances of MoS2 in applications including hydrogen evolution reactions and electrochemical supercapacitors. To this aim, various synthetic methods have been reported to obtain 1 T phase-rich MoS2 . Here, the aim is to evaluate the efficiencies of the bottom-up (hydrothermal reaction) and top-down (chemical exfoliation) approaches in producing 1 T phase MoS2 . It is established in this study that the 1 T phase MoS2 produced through the bottom-up approach contains a high proportion of 1 T phase and demonstrates excellent electrochemical and electrical properties. Its performance in the hydrogen evolution reaction and electrochemical supercapacitors also surpassed that of 1 T phase MoS2 produced through a top-down approach. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

TMT approach to observatory software development process

Science.gov (United States)

Buur, Hanne; Subramaniam, Annapurni; Gillies, Kim; Dumas, Christophe; Bhatia, Ravinder

2016-07-01

effective communications; adopting an agile-based software development process across the observatory to enable frequent software releases to help mitigate subsystem interdependencies; defining concise scope and work packages for each of the OSW subsystems to facilitate effective outsourcing of software deliverables to the ITCC partner, and to enable performance monitoring and risk management. At this stage, the architecture and high-level design of the software system has been established and reviewed. During construction each subsystem will have a final design phase with reviews, followed by implementation and testing. The results of the TMT approach to the Observatory Software development process will only be preliminary at the time of the submittal of this paper, but it is anticipated that the early results will be a favorable indication of progress.

Developing two-phase flow modelling concepts for rock fractures

Energy Technology Data Exchange (ETDEWEB)

Keto, V. (Fortum Nuclear Services Oy, Espoo (Finland))

2010-01-15

The Finnish nuclear waste disposal company, Posiva Oy, is planning an underground repository for spent nuclear fuel to be constructed on the island of Olkiluoto on the south-west coast of Finland. One element of the site investigations conducted at Olkiluoto is the excavation of the underground rock characterisation facility (ONKALO) that will be extended to the final disposal depth (approximately -400 m). The bedrock around the excavated tunnel volume is fully saturated with groundwater, which water commonly contains a mixture of dissolved gases. These gases remain dissolved due to the high hydrostatic pressure. During tunnel excavation work the natural hydrostatic pressure field is disturbed and the water pressure will decrease close to the atmospheric pressure in the immediate vicinity of the tunnel. During this pressure drop two-phase flow conditions (combined flow of both water and gas) may develop in the vicinity of the underground opening, as the dissolved gas is exsoluted under the low pressure (the term exsolution refers here to release of the dissolved gas molecules from the water phase into a separate gas phase). This report steers towards concept development for numerical two-phase flow modeling for fractured rock. The focus is on the description of gas phase formation process under disturbed hydraulic conditions by exsolution of dissolved gases from groundwater, and on understanding the effects of a possibly formed gas phase on groundwater flow conditions in rock fractures. A mathematical model of three mutually coupled nonlinear partial differential equations for two-phase flow is presented and corresponding constitutional relationships are introduced and discussed. Illustrative numerical simulations are performed in a simplified setting using COMSOL Multiphysics 3.5a - software package. Shortcomings and conceptual problems are discussed. (orig.)

Developing two-phase flow modelling concepts for rock fractures

International Nuclear Information System (INIS)

Keto, V.

2010-01-01

The Finnish nuclear waste disposal company, Posiva Oy, is planning an underground repository for spent nuclear fuel to be constructed on the island of Olkiluoto on the south-west coast of Finland. One element of the site investigations conducted at Olkiluoto is the excavation of the underground rock characterisation facility (ONKALO) that will be extended to the final disposal depth (approximately -400 m). The bedrock around the excavated tunnel volume is fully saturated with groundwater, which water commonly contains a mixture of dissolved gases. These gases remain dissolved due to the high hydrostatic pressure. During tunnel excavation work the natural hydrostatic pressure field is disturbed and the water pressure will decrease close to the atmospheric pressure in the immediate vicinity of the tunnel. During this pressure drop two-phase flow conditions (combined flow of both water and gas) may develop in the vicinity of the underground opening, as the dissolved gas is exsoluted under the low pressure (the term exsolution refers here to release of the dissolved gas molecules from the water phase into a separate gas phase). This report steers towards concept development for numerical two-phase flow modeling for fractured rock. The focus is on the description of gas phase formation process under disturbed hydraulic conditions by exsolution of dissolved gases from groundwater, and on understanding the effects of a possibly formed gas phase on groundwater flow conditions in rock fractures. A mathematical model of three mutually coupled nonlinear partial differential equations for two-phase flow is presented and corresponding constitutional relationships are introduced and discussed. Illustrative numerical simulations are performed in a simplified setting using COMSOL Multiphysics 3.5a - software package. Shortcomings and conceptual problems are discussed. (orig.)

Development of Reverse-Phase HPLC Method for Simultaneous ...

African Journals Online (AJOL)

Erah

Purpose: To develop a simple, sensitive and rapid reverse phase HPLC method for the simultaneous analysis of metoprolol succinate and hydrochlorothiazide in a solid dosage form. Methods: The .... Extraction was carried out three times with.

Phase space approach to quantum dynamics

International Nuclear Information System (INIS)

Leboeuf, P.

1991-03-01

The Schroedinger equation for the time propagation of states of a quantised two-dimensional spherical phase space is replaced by the dynamics of a system of N particles lying in phase space. This is done through factorization formulae of analytic function theory arising in coherent-state representation, the 'particles' being the zeros of the quantum state. For linear Hamiltonians, like a spin in a uniform magnetic field, the motion of the particles is classical. However, non-linear terms induce interactions between the particles. Their time propagation is studied and it is shown that, contrary to integrable systems, for chaotic maps they tend to fill, as their classical counterpart, the whole phase space. (author) 13 refs., 3 figs

Local Support Mechanisms for Entrepreneurship: The Approach of Local Development and Innovation Institutions

Directory of Open Access Journals (Sweden)

Katimertzopoulos, F.

2017-03-01

Full Text Available Purpose: The growth potential of SMEs entrepreneurship is examined at regional and local level, initially on a Global scale and then for the case of Greece. Additionally, the possibility of an economic development policy beyond the macroeconomic approach is examined, focusing on business growth and competitiveness in the light of meso and micro-economic policy approach. Design/methodology/approach: This research leads to the proposal of building knowledge mechanisms and direct and efficient systematic development and innovation at the local level, particularity during a time of economic crisis. The establishment of Institutes of Local Development and Innovation (ITAK is primarily geared towards promoting innovative entrepreneurship and extroversion of locally installed businesses. As part of the proposal for the establishment of ITAK, a questionnaire was developed - a tool to initially measure companies' opinions on the need for outside help in the macro, meso and micro environment, in order to demonstrate that ITAK local-level structures could be developed. Findings: The survey results were accrued via the analysis of questionnaires distributed to companies. The results of the questionnaires in the micro-environment in relation to those in the macro-environment shows a lower tendency to change business, which may be because managers perceive economics several times more in macroeconomic terms rather than in meso and micro economic (terms. Research limitations/implications: The restrictions of this particular research are the small sample of study of businesses in one country (Greece; this is because the approach of study, which is quantitative-qualitative, limits analysis to small data sets in the current phase. Originality/value: The results in the micro-environment, in relation to those at macro-environmental, shows a lower tendency to change business, something which may be because managers perceive economics several times more in

Towards the description of the phase behavior of electrolyte solutions in slit-like pores. Density functional approach for the restricted primitive model

Directory of Open Access Journals (Sweden)

O.Pizio

2004-01-01

Full Text Available We develop a density functional approach for the phase behavior of the restricted primitive model for electrolyte solutions confined to slit-like pores. The theory permits to evaluate the effects of confinement on the ionic vapor - ionic liquid coexistence envelope. We have shown that due to confinement in pores with uncharged walls the critical temperature of the model decreases compared to the bulk. Also the coexistence envelope of the transition is narrower in comparison to the bulk model. The transition between dense and dilute phase represents capillary evaporation. We have analyzed changes of the density profiles of ions during transition. Possible extensions of this study are discussed.

Phase development in a U-7 wt.% Mo vs. Al-7 wt.% Ge diffusion couple

Science.gov (United States)

Perez, E.; Keiser, D. D.; Sohn, Y. H.

2013-10-01

Fuel development for the Reduced Enrichment for Research and Test Reactors (RERTR) program has demonstrated that U-Mo alloys in contact with Al develop interaction regions with phases that have poor irradiation behavior. The addition of Si to the Al has been considered with positive results. In this study, compositional modification is considered by replacing Si with Ge to determine the effect on the phase development in the system. The microstructural and phase development of a diffusion couple of U-7 wt.% Mo in contact with Al-7 wt.% Ge was examined by transmission electron microscopy, scanning electron microscopy and energy dispersive spectroscopy. The interdiffusion zone developed a microstructure that included the cubic-UGe3 phase and amorphous phases. The UGe3 phase was observed with and without Mo and Al solid solution developing a (U,Mo)(Al,Ge)3 phase.

Need for multiple approaches in collaborative software development

International Nuclear Information System (INIS)

LePoire, D. J.

2002-01-01

The need to share software and reintegrate it into new applications presents a difficult but important challenge. Component-based development as an approach to this problem is receiving much attention in professional journals and academic curricula. However, there are many other approaches to collaborative software development that might be more appropriate. This paper reviews a few of these approaches and discusses criteria for the conditions and contexts in which these alternative approaches might be more appropriate. This paper complements the discussion of context-based development team organizations and processes. Examples from a small development team that interacts with a larger professional community are analyzed

Beyond Design: The Importance of Construction and Post-Construction Phases in Green Developments

Directory of Open Access Journals (Sweden)

Mark Hostetler

2010-04-01

Full Text Available Green developments are becoming a popular land use planning concept that attempts to accommodate growth while minimizing impacts on natural resources. Various policies encourage conservation designs that usually translate into the clustering of homes and the conservation of some percentage of open space. However, the success of a design is determined by what happens during the construction and post-construction phases of a subdivision project. These two phases are often ignored in land use planning and given only minimal attention by built environment professionals. As a result, green developments may not be functioning as originally intended. This essay discusses the importance of construction and post-construction and a way forward to create functional, sustainable communities. Construction activities and decisions, such as impacts from earthwork machines, improper protection of conserved open spaces and trees, the choice of plants used for yards and common areas, and the storage of construction material all can lead to severe impacts on natural areas both within and surrounding a development site. During post-construction, a variety of improper management practices by homeowners can compromise the sustainability of a development. Developers and associated environmental consultant teams could implement approaches that would engage contractors and residents, such as environmental construction covenants and the installment of a neighborhood, environmental education program. To increase the adoption of relevant construction and post-construction practices, appropriate policies need to be created. However, the shift will only occur once the planning and built environment community acknowledges that design is only the first step towards sustainability. Academic design studios and continuing education courses can help with this culture shift by including construction and post-construction considerations within their curriculum.

Development of Zinc/Bromine Batteries for Load-Leveling Applications: Phase 2 Final Report

Energy Technology Data Exchange (ETDEWEB)

CLARK,NANCY H.; EIDLER,PHILLIP

1999-10-01

This report documents Phase 2 of a project to design, develop, and test a zinc/bromine battery technology for use in utility energy storage applications. The project was co-funded by the U.S. Department of Energy Office of Power Technologies through Sandia National Laboratories. The viability of the zinc/bromine technology was demonstrated in Phase 1. In Phase 2, the technology developed during Phase 1 was scaled up to a size appropriate for the application. Batteries were increased in size from 8-cell, 1170-cm{sup 2} cell stacks (Phase 1) to 8- and then 60-cell, 2500-cm{sup 2} cell stacks in this phase. The 2500-cm{sup 2} series battery stacks were developed as the building block for large utility battery systems. Core technology research on electrolyte and separator materials and on manufacturing techniques, which began in Phase 1, continued to be investigated during Phase 2. Finally, the end product of this project was a 100-kWh prototype battery system to be installed and tested at an electric utility.

Toward a Cooperative Experimental System Development Approach

DEFF Research Database (Denmark)

Grønbæk, Kaj; Kyng, Morten; Mogensen, Preben Holst

1997-01-01

This chapter represents a step towards the establishment of a new system development approach, called Cooperative Experimental System Development (CESD). CESD seeks to overcome a number of limitations in existing approaches: specification oriented methods usually assume that system design can...... be based solely on observation and detached reflection; prototyping methods often have a narrow focus on the technical construction of various kinds of prototypes; Participatory Design techniques—including the Scandinavian Cooperative Design (CD) approaches—seldom go beyond the early analysis....../design activities of development projects. In contrast, the CESD approach is characterized by its focus on: active user involvement throughout the entire development process; prototyping experiments closely coupled to work-situations and use-scenarios; transforming results from early cooperative analysis...

Diagrammatic methods in phase-space regularization

International Nuclear Information System (INIS)

Bern, Z.; Halpern, M.B.; California Univ., Berkeley

1987-11-01

Using the scalar prototype and gauge theory as the simplest possible examples, diagrammatic methods are developed for the recently proposed phase-space form of continuum regularization. A number of one-loop and all-order applications are given, including general diagrammatic discussions of the nogrowth theorem and the uniqueness of the phase-space stochastic calculus. The approach also generates an alternate derivation of the equivalence of the large-β phase-space regularization to the more conventional coordinate-space regularization. (orig.)

Phase development in a U–7 wt.% Mo vs. Al–7 wt.% Ge diffusion couple

Energy Technology Data Exchange (ETDEWEB)

Perez, E., E-mail: Emmanuel.Perez@inl.gov [Nuclear Fuels and Materials Development, Idaho National Laboratory, Box 1625, Idaho Falls, ID 83415 (United States); Keiser, D.D. [Nuclear Fuels and Materials Development, Idaho National Laboratory, Box 1625, Idaho Falls, ID 83415 (United States); Sohn, Y.H. [Advanced Materials Processing and Analysis Center, and Department of Materials Science and Engineering, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816 (United States)

2013-10-15

Fuel development for the Reduced Enrichment for Research and Test Reactors (RERTR) program has demonstrated that U–Mo alloys in contact with Al develop interaction regions with phases that have poor irradiation behavior. The addition of Si to the Al has been considered with positive results. In this study, compositional modification is considered by replacing Si with Ge to determine the effect on the phase development in the system. The microstructural and phase development of a diffusion couple of U–7 wt.% Mo in contact with Al–7 wt.% Ge was examined by transmission electron microscopy, scanning electron microscopy and energy dispersive spectroscopy. The interdiffusion zone developed a microstructure that included the cubic-UGe{sub 3} phase and amorphous phases. The UGe{sub 3} phase was observed with and without Mo and Al solid solution developing a (U,Mo)(Al,Ge){sub 3} phase.

eHealth development: a holistic approach

NARCIS (Netherlands)

Lentferink, Aniek

2016-01-01

This presentation was held during the course 'eHealth development a holistic approach' at the University of Twente. The presentation included information about the project Quantified Self at Work and specifically the approach of co-creation during eHealth design with important stakeholders.

High-Temperature Phase Equilibria of Duplex Stainless Steels Assessed with a Novel In-Situ Neutron Scattering Approach

Science.gov (United States)

Pettersson, Niklas; Wessman, Sten; Hertzman, Staffan; Studer, Andrew

2017-04-01

Duplex stainless steels are designed to solidify with ferrite as the parent phase, with subsequent austenite formation occurring in the solid state, implying that, thermodynamically, a fully ferritic range should exist at high temperatures. However, computational thermodynamic tools appear currently to overestimate the austenite stability of these systems, and contradictory data exist in the literature. In the present work, the high-temperature phase equilibria of four commercial duplex stainless steel grades, denoted 2304, 2101, 2507, and 3207, with varying alloying levels were assessed by measurements of the austenite-to-ferrite transformation at temperatures approaching 1673 K (1400 °C) using a novel in-situ neutron scattering approach. All grades became fully ferritic at some point during progressive heating. Higher austenite dissolution temperatures were measured for the higher alloyed grades, and for 3207, the temperature range for a single-phase ferritic structure approached zero. The influence of temperatures in the region of austenite dissolution was further evaluated by microstructural characterization using electron backscattered diffraction of isothermally heat-treated and quenched samples. The new experimental data are compared to thermodynamic calculations, and the precision of databases is discussed.

Philosophy and possible approach to SAMG development

International Nuclear Information System (INIS)

Sartmadjiev, A.

1999-01-01

In this lecture are discussed: Safety functional relationship; Basic principles for development and implementation of SAMG; and Determination of the plant damage condition. Phases of the SA management are presented

An Evaluation System for Training Programs: A Case Study Using a Four-Phase Approach

Science.gov (United States)

Lingham, Tony; Richley, Bonnie; Rezania, Davar

2006-01-01

Purpose: With the increased importance of training in organizations, creating important and meaningful programs are critical to an organization and its members. The purpose of this paper is to suggest a four-phase systematic approach to designing and evaluating training programs that promotes collaboration between organizational leaders, trainers,…

Analysis and numerical simulation of compressible two-phase flows using relaxation methods. Contribution to the treatment of vanishing phases

International Nuclear Information System (INIS)

Saleh, K.

2012-01-01

This thesis deals with the Baer-Nunziato two-phase flow model. The main objective of this work is to propose some techniques to cope with phase vanishing regimes which produce important instabilities in the model and its numerical simulations. Through analysis and simulation methods using Suliciu relaxation approximations, we prove that in these regimes, the solutions can be stabilised by introducing some extra dissipation of the total mixture entropy. In a first approach, called the Eulerian approach, the exact resolution of the relaxation Riemann problem provides an accurate entropy-satisfying numerical scheme, which turns out to be much more efficient in terms of CPU-cost than the classical and very simple Rusanov's scheme. Moreover, the scheme is proved to handle the vanishing phase regimes with great stability. The scheme, first developed in 1D, is then extended in 3D and implemented in an industrial code developed by EDF. The second approach, called the acoustic splitting approach, considers a separation of fast acoustic waves from slow material waves. The objective is to avoid the resonance due to the interaction between these two types of waves, and to allow an implicit treatment of the acoustics, while material waves are explicitly discretized. The resulting scheme is very simple and allows to deal simply with phase vanishing. The originality of this work is to use new dissipative closure laws for the interfacial velocity and pressure, in order to control the solutions of the Riemann problem associated with the acoustic step, in the phase vanishing regimes. (author)

Unusual dileptions at RHIC a field theoretic approach based on a non-equilibrium chiral phase transition

International Nuclear Information System (INIS)

Cooper, F.

1997-01-01

This paper contains viewgraphs on unusual dileptons at Brookhaven RHIC. A field theory approach is used based on a non-equilibrium chiral phase transformation utilizing the schroedinger and Heisenberg picture

Unusual dileptions at RHIC a field theoretic approach based on a non-equilibrium chiral phase transition

Energy Technology Data Exchange (ETDEWEB)

Cooper, F. [Los Alamos National Labs., NM (United States)

1997-09-22

This paper contains viewgraphs on unusual dileptons at Brookhaven RHIC. A field theory approach is used based on a non-equilibrium chiral phase transformation utilizing the schroedinger and Heisenberg picture.

Fundamentals of ultrasonic phased arrays

CERN Document Server

Schmerr, Lester W

2014-01-01

This book describes in detail the physical and mathematical foundations of ultrasonic phased array measurements.?The book uses linear systems theory to develop a comprehensive model of the signals and images that can be formed with phased arrays. Engineers working in the field of ultrasonic nondestructive evaluation (NDE) will find in this approach a wealth of information on how to design, optimize and interpret ultrasonic inspections with phased arrays. The fundamentals and models described in the book will also be of significant interest to other fields, including the medical ultrasound and

Moving forward in uveitis therapy: preclinical to phase II clinical trial drug development.

Science.gov (United States)

Salazar-Méndez, Raquel; Yilmaz, Taygan; Cordero-Coma, Miguel

2016-01-01

Several advances have been made in the diagnostic approach and therapeutic management of patients with immune-mediated uveitis over the last few decades, which have to lead to an improvement in the visual prognosis of patients. However, the use of available therapies, including steroids and immunosuppressive drugs, is still associated with limited efficacy and potentially serious side effects. Consequently, efforts have been made to develop novel therapeutic alternatives including new molecules and innovative therapeutic approaches. Herein, the authors provide an updated review of those drugs in the initial phases of evaluation for the treatment of immune-mediated uveitides as well as the latest evidence from basic research. Enhanced understanding of the pathogenic mechanisms leading to immune-mediated uveitis has led to the identification of new therapeutic targets and thus to the development of more specific drugs. In addition, considering that the eye is a semi-enclosed chamber and that local therapy has the benefit of sparing the rest of the body from potentially toxic exposure, several attempts of establishing direct ophthalmologic avenues for delivery of the established and emerging drugs have also been made. All these advances have been an unquestionable step forward in the challenging management of uveitis patients.

Electronic structure theory of alloy phase stability

International Nuclear Information System (INIS)

Turchi, P.E.A.; Sluiter, M.

1992-01-01

We present a brief overview of the advanced methodology which has been developed and applied to the study of phase stability properties in substitutional alloys. The approach is based on the real space version of the Generalized Perturbation Method within the Korringa-Kohn-Rostoker multiple scattering formulation of the Coherent Potential Approximation. Temperature effects are taken into account with a generalized meanfield approach, namely the Cluster Variation Method, or with Monte-Carlo simulations. We show that this approach is well suited for studying ground state properties of substitutional alloys, for calculating energies of idealized interfaces and antiphase boundaries, and finally to compute alloy phase diagrams

Technical Approach for the Development of a Near Tank Cesium Removal Process

International Nuclear Information System (INIS)

Sams, T.L.; Miller, Ch.E.; Kurath, D.E.; Blanchard, D.L.

2009-01-01

Parsons has been selected for development of two Advanced Remediation Technology (ART) projects. One of these projects is the Near Tank Cesium Removal (NTCR) project. The NTCR system uses the same basic ion exchange approach for Cs removal that has been used for decades in the nuclear industry. The essential difference in this approach is the development of a modular, mobile design concept based on a simplified process employing an advanced resin media and the use of cool nitric acid for elution and heated nitric acid for resin digestion. Under these conditions, the NTCR process shows significant improvements over the baseline ion exchange technology. These improvements will allow DOE to deploy a NTCR, free up tank space and accelerate closure of SSTs prior to Waste Treatment Plant Pretreatment Facility startup (WTP PTF). Current estimates indicate that the Hanford tank farm system will run out of available storage space prior to startup of the WTP PTF currently scheduled for 2019. The lack of tank space will constrain the near-term goal of retrieving waste from single-shell tanks prior to full operation of the WTP. A deployment of an NTCR system will allow LAW processing to begin as soon as supplemental treatment (e.g. Bulk Vitrification) or the WTP LAW Vitrification Facility becomes available. The NTCR system is a self contained modular, transportable system that requires only limited process chemicals and separates the HLW into two process streams. Once the cesium is removed, the low activity waste stream can be vitrified. The high activity stream would be stored in the DST system until vitrified by the WTP High Level Waste (HLW) Facility. This technology can be sized to feed the WTP LAW melters at the nominal operating capacity (30 MT glass per day. Alternatively, it could be sized to feed a supplemental treatment system such the Bulk Vitrification process. The NTCR system is based on an elutable ion exchange system using the Spherical Resorcinol Formaldehyde

Centralised, decentralised or hybrid sanitation systems? Economic evaluation under urban development uncertainty and phased expansion.

Science.gov (United States)

Roefs, Ivar; Meulman, Brendo; Vreeburg, Jan H G; Spiller, Marc

2017-02-01

Sanitation systems are built to be robust, that is, they are dimensioned to cope with population growth and other variability that occurs throughout their lifetime. It was recently shown that building sanitation systems in phases is more cost effective than one robust design. This phasing can take place by building small autonomous decentralised units that operate closer to the actual demand. Research has shown that variability and uncertainty in urban development does affect the cost effectiveness of this approach. Previous studies do not, however, consider the entire sanitation system from collection to treatment. The aim of this study is to assess the economic performance of three sanitation systems with different scales and systems characteristics under a variety of urban development pathways. Three systems are studied: (I) a centralised conventional activated sludge treatment, (II) a community on site source separation grey water and black water treatment and (III) a hybrid with grey water treatment at neighbourhood scale and black water treatment off site. A modelling approach is taken that combines a simulation of greenfield urban growth, a model of the wastewater collection and treatment infrastructure design properties and a model that translates design parameters into discounted asset lifetime costs. Monte Carlo simulations are used to evaluate the economic performance under uncertain development trends. Results show that the conventional system outperforms both of the other systems when total discounted lifetime costs are assessed, because it benefits from economies of scale. However, when population growth is lower than expected, the source-separated system is more cost effective, because of reduced idle capacity. The hybrid system is not competitive under any circumstance due to the costly double piping and treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cross-Platform Mobile Application Development: A Pattern-Based Approach

Science.gov (United States)

2012-03-01

TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Cross-Platform Mobile Application Development: A Pattern-Based Approach 5. FUNDING...for public release; distribution is unlimited CROSS-PLATFORM MOBILE APPLICATION DEVELOPMENT: A PATTERN-BASED APPROACH Christian G. Acord...occurring design problems. We then discuss common approaches to mobile development, including common aspects of mobile application development, including

Trapping control of phase development in zone melting of Bi-Sr-Ca-Cu-O superconducting fibres

International Nuclear Information System (INIS)

Costa, F M; Carrasco, M F; Silva, R F; Vieira, J M

2003-01-01

Highly-texturized polycrystalline fibres of the Bi-Sr-Ca-Cu-O system have been grown by the laser floating zone technique at seven different pulling rates: (1.1, 2.2, 4.17, 8.3, 16.7, 33.3, 60.5) x 10 -6 m s -1 . The assessment of the cation segregation at the solid/liquid interface allowed us to calculate their equilibrium and effective distribution coefficients. The equilibrium distribution coefficients (k 0,Bi = 0.55, k 0,Sr = 0.97, k 0,Ca = 1.67, k 0,Cu = 1.10) were estimated using the Burton, Primm and Slichter (BPS) theory by taking into account the determined effective values. The effective distribution coefficients tend to unity as long as the pulling rate increases. The composition profiles along the initial transient region of the solidified fibres show a fast approach to the nominal composition as the pulling rate increases. The outstanding effect of the growth speed on superconducting phase type development is explained based on the solute trapping phenomena. The sequence of crystallization for superconducting phases ('2212' → '4413' → '2201') with pulling rate is a spontaneous effect of the system thermodynamics in order to balance the Bi trapping. This phase sequence corresponds to the smallest change of Bi chemical potential from the liquid phase to the solid phase. A diagram of free energy curves of the interdendritic superconducting phases illustrates the partitionless solidification phenomena at the highest growth speed

Identifying seizure onset zone from electrocorticographic recordings: A machine learning approach based on phase locking value.

Science.gov (United States)

Elahian, Bahareh; Yeasin, Mohammed; Mudigoudar, Basanagoud; Wheless, James W; Babajani-Feremi, Abbas

2017-10-01

Using a novel technique based on phase locking value (PLV), we investigated the potential for features extracted from electrocorticographic (ECoG) recordings to serve as biomarkers to identify the seizure onset zone (SOZ). We computed the PLV between the phase of the amplitude of high gamma activity (80-150Hz) and the phase of lower frequency rhythms (4-30Hz) from ECoG recordings obtained from 10 patients with epilepsy (21 seizures). We extracted five features from the PLV and used a machine learning approach based on logistic regression to build a model that classifies electrodes as SOZ or non-SOZ. More than 96% of electrodes identified as the SOZ by our algorithm were within the resected area in six seizure-free patients. In four non-seizure-free patients, more than 31% of the identified SOZ electrodes by our algorithm were outside the resected area. In addition, we observed that the seizure outcome in non-seizure-free patients correlated with the number of non-resected SOZ electrodes identified by our algorithm. This machine learning approach, based on features extracted from the PLV, effectively identified electrodes within the SOZ. The approach has the potential to assist clinicians in surgical decision-making when pre-surgical intracranial recordings are utilized. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Phase transition approach to bursting in neuronal cultures: quorum percolation models

Science.gov (United States)

Monceau, P.; Renault, R.; Métens, S.; Bottani, S.; Fardet, T.

2017-10-01

The Quorum Percolation model has been designed in the context of neurobiology to describe bursts of activity occurring in neuronal cultures from the point of view of statistical physics rather than from a dynamical synchronization approach. It is based upon information propagation on a directed graph with a threshold activation rule; this leads to a phase diagram which exhibits a giant percolation cluster below some critical value mC of the excitability. We describe the main characteristics of the original model and derive extensions according to additional relevant biological features. Firstly, we investigate the effects of an excitability variability on the phase diagram and show that the percolation transition can be destroyed by a sufficient amount of such a disorder; we stress the weakly averaging character of the order parameter and show that connectivity and excitability can be seen as two overlapping aspects of the same reality. Secondly, we elaborate a discrete time stochastic model taking into account the decay originating from ionic leakage through the membrane of neurons and synaptic depression; we give evidence that the decay softens and shifts the transition, and conjecture than decay destroys the transition in the thermodynamical limit. We were able to develop mean-field theories associated with each of the two effects; we discuss the framework of their agreement with Monte Carlo simulations. It turns out that the the critical point mC from which information on the connectivity of the network can be inferred is affected by each of these additional effects. Lastly, we show how dynamical simulations of bursts with an adaptive exponential integrateand- fire model can be interpreted in terms of Quorum Percolation. Moreover, the usefulness of the percolation model including the set of sophistication we investigated can be extended to many scientific fields involving information propagation, such as the spread of rumors in sociology, ethology, ecology.

A novel biased proportional navigation guidance law for close approach phase

Directory of Open Access Journals (Sweden)

Su Wenshan

2016-02-01

Full Text Available A novel biased proportional navigation guidance (BPNG law is proposed for the close approach phase, which aims to make the spacecraft rendezvous with the target in specific relative range and direction. Firstly, in order to describe the special guidance requirements, the concept of zero effort miss vector is proposed and the dangerous area where there exists collision risk for safety consideration is defined. Secondly, the BPNG, which decouples the range control and direction control, is designed in the line-of-sight (LOS rotation coordinate system. The theoretical analysis proves that BPNG meets guidance requirements quite well. Thirdly, for the consideration of fuel consumption, the optimal biased proportional navigation guidance (OBPNG law is derived by solving the Schwartz inequality. Finally, simulation results show that BPNG is effective for the close approach with the ability of evading the dangerous area and OBPNG consumes less fuel compared with BPNG.

NASA Research Announcement Phase 1 Report and Phase 2 Proposal for the Development of a Power Assisted Space Suit Glove Assembly

Science.gov (United States)

Cadogan, Dave; Lingo, Bob

1996-01-01

In July of 1996, ILC Dover was awarded Phase 1 of a contract for NASA to develop a prototype Power Assisted Space Suit glove to enhance the performance of astronauts during Extra-Vehicular Activity (EVA). This report summarizes the work performed to date on Phase 1, and details the work to be conducted on Phase 2 of the program. Phase 1 of the program consisted of research and review of related technical sources, concept brainstorming, baseline design development, modeling and analysis, component mock-up testing, and test data analysis. ILC worked in conjunction with the University of Maryland's Space Systems Laboratory (SSL) to develop the power assisted glove. Phase 2 activities will focus on the design maturation and the manufacture of a working prototype system. The prototype will be tested and evaluated in conjunction with existing space suit glove technology to determine the performance enhancement anticipated with the implementation of the power assisted joint technology in space suit gloves.

Preliminary Development of Real Time Usage-Phase Monitoring System for CNC Machine Tools with a Case Study on CNC Machine VMC 250

Science.gov (United States)

Budi Harja, Herman; Prakosa, Tri; Raharno, Sri; Yuwana Martawirya, Yatna; Nurhadi, Indra; Setyo Nogroho, Alamsyah

2018-03-01

The production characteristic of job-shop industry at which products have wide variety but small amounts causes every machine tool will be shared to conduct production process with dynamic load. Its dynamic condition operation directly affects machine tools component reliability. Hence, determination of maintenance schedule for every component should be calculated based on actual usage of machine tools component. This paper describes study on development of monitoring system to obtaining information about each CNC machine tool component usage in real time approached by component grouping based on its operation phase. A special device has been developed for monitoring machine tool component usage by utilizing usage phase activity data taken from certain electronics components within CNC machine. The components are adaptor, servo driver and spindle driver, as well as some additional components such as microcontroller and relays. The obtained data are utilized for detecting machine utilization phases such as power on state, machine ready state or spindle running state. Experimental result have shown that the developed CNC machine tool monitoring system is capable of obtaining phase information of machine tool usage as well as its duration and displays the information at the user interface application.

A more rational approach to new-product development.

Science.gov (United States)

Bonabeau, Eric; Bodick, Neil; Armstrong, Robert W

2008-03-01

Companies often treat new-product development as a monolithic process, but it can be more rationally divided into two parts: an early stage that focuses on evaluating prospects and eliminating bad bets, and a late stage that maximizes the remaining candidates' market potential. Recognizing the value of this approach, Eli Lilly designed and piloted Chorus, an autonomous unit dedicated solely to the early stage. This article demonstrates how segmenting development in this way can speed it up and make it more cost-effective. Two classes of decision-making errors can impede NPD, the authors say. First, managers often ignore evidence challenging their assumptions that projects will succeed. As a result, many projects go forward despite multiple red flags; some even reach the market, only to fail dramatically after their introduction. Second, companies sometimes terminate projects prematurely because people fail to conduct the right experiments to reveal products' potential. Most companies promote both kinds of errors by focusing disproportionately on late-stage development; they lack the early, truth-seeking functions that would head such errors off. In segmented NPD, however, the early-stage organization maintains loyalty to the experiment rather than the product, whereas the late-stage organization pursues commercial success. Chorus has significantly improved NPD efficiency and productivity at Lilly. Although the unit absorbs just one-tenth of Lilly's investment in early-stage development, it delivers a substantially greater fraction of the molecules slated for late Phase II trials--at almost twice the speed and less than a third of the cost of the standard process, sometimes shaving as much as two years off the usual development time.

Development of Phase Detection Schemes Based on Surface Plasmon Resonance Using Interferometry

Directory of Open Access Journals (Sweden)

Muhammad Kashif

2014-08-01

Full Text Available Surface plasmon resonance (SPR is a novel optical sensing technique with a unique ability to monitor molecular binding in real-time for biological and chemical sensor applications. Interferometry is an excellent tool for accurate measurement of SPR changes, the measurement and comparison is made for the sensitivity, dynamic range and resolution of the different analytes using interferometry techniques. SPR interferometry can also employ phase detection in addition to the amplitude of the reflected light wave, and the phase changes more rapidly compared with other approaches, i.e., intensity, angle and wavelength. Therefore, the SPR phase interferometer offers the advantages of spatial phase resolution and high sensitivity. This work discusses the advancements in interferometric SPR methods to measure the phase shifts due to refractive index changes. The main application areas of SPR sensors are demonstrated, i.e., the Fabry-Perot interferometer, Michelson interferometer and Mach-Zehnder interferometer, with different configurations. The three interferometers are discussed in detail, and solutions are suggested to enhance the performance parameters that will aid in future biological and chemical sensors.

Application of dual-anneal diffusion multiples to the effective study of phase diagrams and phase transformations in the Fe–Cr–Ni system

International Nuclear Information System (INIS)

Cao, Siwei; Zhao, Ji-Cheng

2015-01-01

A dual-anneal diffusion multiple (DADM) approach is developed for effective determination of intermediate-temperature phase diagrams that are critical to the establishment of reliable thermodynamic databases. A large amount of phase equilibrium data was obtained from DADMs to construct the Fe–Cr–Ni isothermal sections at 1200, 900, 800 and 700 °C. The DADM approach is also a systematic and effective way to study phase precipitation from wide ranges of compositions, thus generating rich atlases of microstructures induced by various transformations. The results from this study indicate that the body-centered cubic to sigma phase transformation in the Fe–Cr–Ni system took place initially through a massive transformation mechanism

Analyzing Information Systems Development: A Comparison and Analysis of Eight IS Development Approaches.

Science.gov (United States)

Iivari, Juhani; Hirschheim, Rudy

1996-01-01

Analyzes and compares eight information systems (IS) development approaches: Information Modelling, Decision Support Systems, the Socio-Technical approach, the Infological approach, the Interactionist approach, the Speech Act-based approach, Soft Systems Methodology, and the Scandinavian Trade Unionist approach. Discusses the organizational roles…

An acoustic-convective splitting-based approach for the Kapila two-phase flow model

Energy Technology Data Exchange (ETDEWEB)

Eikelder, M.F.P. ten, E-mail: m.f.p.teneikelder@tudelft.nl [EDF R& D, AMA, 7 boulevard Gaspard Monge, 91120 Palaiseau (France); Eindhoven University of Technology, Department of Mathematics and Computer Science, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Daude, F. [EDF R& D, AMA, 7 boulevard Gaspard Monge, 91120 Palaiseau (France); IMSIA, UMR EDF-CNRS-CEA-ENSTA 9219, Université Paris Saclay, 828 Boulevard des Maréchaux, 91762 Palaiseau (France); Koren, B.; Tijsseling, A.S. [Eindhoven University of Technology, Department of Mathematics and Computer Science, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2017-02-15

In this paper we propose a new acoustic-convective splitting-based numerical scheme for the Kapila five-equation two-phase flow model. The splitting operator decouples the acoustic waves and convective waves. The resulting two submodels are alternately numerically solved to approximate the solution of the entire model. The Lagrangian form of the acoustic submodel is numerically solved using an HLLC-type Riemann solver whereas the convective part is approximated with an upwind scheme. The result is a simple method which allows for a general equation of state. Numerical computations are performed for standard two-phase shock tube problems. A comparison is made with a non-splitting approach. The results are in good agreement with reference results and exact solutions.

Exploring the hole cleaning parameters of horizontal wellbore using two-phase Eulerian CFD approach

Directory of Open Access Journals (Sweden)

Satish K Dewangan

2016-03-01

Full Text Available The present investigation deals with the flow through concentric annulus with the inner cylinder in rotation. This work has got its importance in the petroleum industries in relation to the wellbore drilling. In wellbore drilling, the issue of the hole-cleaning is very serious problem especially in case of the horizontal drilling process. The effect of the various parameters like slurry flow velocity, inner cylinder rotational speed, inlet solid concentration which affect hole cleaning was discussed. Their effect on the pressure drop, wall shear stress, mixture turbulence kinetic energy, and solid-phase velocity and slip velocity were analyzed, which are responsible for solid-phase distribution. Flow was considered to be steady, incompressible and two-phase slurry flow with water as carrier fluid and silica sand as the secondary phase. Eulerian approach was used for modeling the slurry flow. Silica sand was considered of spherical shape with particle size of 180 µm. ANSYS FLUENT software was used for modeling and solution. Plotting was done using Tecplot software and Microsoft Office.

On the development and benchmarking of an approach to model gas transport in fractured media with immobile water storage

Science.gov (United States)

Harp, D. R.; Ortiz, J. P.; Pandey, S.; Karra, S.; Viswanathan, H. S.; Stauffer, P. H.; Anderson, D. N.; Bradley, C. R.

2017-12-01

In unsaturated fractured media, the rate of gas transport is much greater than liquid transport in many applications (e.g., soil vapor extraction operations, methane leaks from hydraulic fracking, shallow CO2 transport from geologic sequestration operations, and later-time radionuclide gas transport from underground nuclear explosions). However, the relatively immobile pore water can inhibit or promote gas transport for soluble constituents by providing storage. In scenarios with constant pressure gradients, the gas transport will be retarded. In scenarios with reversing pressure gradients (i.e. barometric pressure variations) pore water storage can enhance gas transport by providing a ratcheting mechanism. Recognizing the computational efficiency that can be gained using a single-phase model and the necessity of considering pore water storage, we develop a Richard's solution approach that includes kinetic dissolution/volatilization of constituents. Henry's Law governs the equilibrium gaseous/aqueous phase partitioning in the approach. The approach is implemented in a development branch of the PFLOTRAN simulator. We verify the approach with analytical solutions of: (1) 1D gas diffusion, (2) 1D gas advection, (3) sinusoidal barometric pumping of a fracture, and (4) gas transport along a fracture with uniform flow and diffusive walls. We demonstrate the retardation of gas transport in cases with constant pressure gradients and the enhancement of gas transport with reversing pressure gradients. The figure presents the verification of our approach to the analytical solution of barometric pumping of a fracture from Nilson et al (1991) where the x-axis "Horizontal axis" is the distance into the matrix block from the fracture.

Shear-induced phase changes in mixtures

International Nuclear Information System (INIS)

Romig, K.D.; Hanley, H.J.M.

1986-01-01

A thermodynamic theory to account for the behavior of liquid mixtures exposed to a shear is developed. One consequence of the theory is that shear-induced phase changes are predicted. The theory is based on a thermodynamics that includes specifically the shear rate in the formalism and is applied to mixtures by a straightforward modification of the corresponding states, conformalsolution approach. The approach is general but is used here for a mixture of Lennard-Jones particles with a Lennard-Jones equation of state as a reference fluid. The results are discussed in the context of the Scott and Van Konynenberg phase classification. It is shown that the influence of a shear does affect substantially the type of the phase behavior. Results from the model mixture are equated loosely with those from real polymeric liquids

Dynamical Systems Approaches to Emotional Development

Science.gov (United States)

Camras, Linda A.; Witherington, David C.

2005-01-01

Within the last 20 years, transitions in the conceptualization of emotion and its development have given rise to calls for an explanatory framework that captures emotional development in all its organizational complexity and variability. Recent attempts have been made to couch emotional development in terms of a dynamical systems approach through…

Developing a novel hierarchical approach for multiscale structural reliability predictions for ultra-high consequence applications

Energy Technology Data Exchange (ETDEWEB)

Emery, John M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Coffin, Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robbins, Brian A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carroll, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Field, Richard V. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jeremy Yoo, Yung Suk [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kacher, Josh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

Microstructural variabilities are among the predominant sources of uncertainty in structural performance and reliability. We seek to develop efficient algorithms for multiscale calcu- lations for polycrystalline alloys such as aluminum alloy 6061-T6 in environments where ductile fracture is the dominant failure mode. Our approach employs concurrent multiscale methods, but does not focus on their development. They are a necessary but not sufficient ingredient to multiscale reliability predictions. We have focused on how to efficiently use concurrent models for forward propagation because practical applications cannot include fine-scale details throughout the problem domain due to exorbitant computational demand. Our approach begins with a low-fidelity prediction at the engineering scale that is sub- sequently refined with multiscale simulation. The results presented in this report focus on plasticity and damage at the meso-scale, efforts to expedite Monte Carlo simulation with mi- crostructural considerations, modeling aspects regarding geometric representation of grains and second-phase particles, and contrasting algorithms for scale coupling.

Gravitational wave generation from bubble collisions in first-order phase transitions: An analytic approach

International Nuclear Information System (INIS)

Caprini, Chiara; Durrer, Ruth; Servant, Geraldine

2008-01-01

Gravitational wave production from bubble collisions was calculated in the early 1990s using numerical simulations. In this paper, we present an alternative analytic estimate, relying on a different treatment of stochasticity. In our approach, we provide a model for the bubble velocity power spectrum, suitable for both detonations and deflagrations. From this, we derive the anisotropic stress and analytically solve the gravitational wave equation. We provide analytical formulas for the peak frequency and the shape of the spectrum which we compare with numerical estimates. In contrast to the previous analysis, we do not work in the envelope approximation. This paper focuses on a particular source of gravitational waves from phase transitions. In a companion article, we will add together the different sources of gravitational wave signals from phase transitions: bubble collisions, turbulence and magnetic fields and discuss the prospects for probing the electroweak phase transition at LISA

Development of portable phased array UT system for real-time flaw imaging

International Nuclear Information System (INIS)

Goto, M.

1995-01-01

Many functions and features of phased array UT technology must be useful for NDE in the industrial field. Some phased array UT systems have been developed for the inspection of nuclear pressure vessel and turbine components. However, phased array UT is still a special NDE technique and it has not been used widely in the past. The reasons of that are system size, cost, operator performance, equipment design and others. TOSHIBA has newly developed PC controlled portable phased array system to solve those problems. The portable phased array UT system is very compact and light but it is able to drive up to 32-channel linear array probe, to display real-time linear/sector B-scan, to display accumulated B-scan with an encoder and to display profile overlaid B-scan. The first applications were turbine component inspections for precise flaw investigation and flaw image data recording

Development of a Ground Test and Analysis Protocol for NASA's NextSTEP Phase 2 Habitation Concepts

Science.gov (United States)

Gernhardt, Michael L.; Beaton, Kara H.; Chappell, Steven P.; Bekdash, Omar S.; Abercromby, Andrew F. J.

2018-01-01

The NASA Next Space Technologies for Exploration Partnerships (NextSTEP) program is a public-private partnership model that seeks commercial development of deep space exploration capabilities to support human spaceflight missions around and beyond cislunar space. NASA first issued the Phase 1 NextSTEP Broad Agency Announcement to U.S. industries in 2014, which called for innovative cislunar habitation concepts that leveraged commercialization plans for low-Earth orbit. These habitats will be part of the Deep Space Gateway (DSG), the cislunar space station planned by NASA for construction in the 2020s. In 2016, Phase 2 of the NextSTEP program selected five commercial partners to develop ground prototypes. A team of NASA research engineers and subject matter experts (SMEs) have been tasked with developing the ground-test protocol that will serve as the primary means by which these Phase 2 prototypes will be evaluated. Since 2008, this core test team has successfully conducted multiple spaceflight analog mission evaluations utilizing a consistent set of operational tools, methods, and metrics to enable the iterative development, testing, analysis, and validation of evolving exploration architectures, operations concepts, and vehicle designs. The purpose of implementing a similar evaluation process for the Phase 2 Habitation Concepts is to consistently evaluate different commercial partner ground prototypes to provide data-driven, actionable recommendations for Phase 3. This paper describes the process by which the ground test protocol was developed and the objectives, methods, and metrics by which the NextSTEP Phase 2 Habitation Concepts will be rigorously and systematically evaluated. The protocol has been developed using both a top-down and bottom-up approach. Top-down development began with the Human Exploration and Operations Mission Directorate (HEOMD) exploration objectives and ISS Exploration Capability Study Team (IECST) candidate flight objectives. Strategic

A general approach for haplotype phasing across the full spectrum of relatedness.

Directory of Open Access Journals (Sweden)

Jared O'Connell

2014-04-01

Full Text Available Many existing cohorts contain a range of relatedness between genotyped individuals, either by design or by chance. Haplotype estimation in such cohorts is a central step in many downstream analyses. Using genotypes from six cohorts from isolated populations and two cohorts from non-isolated populations, we have investigated the performance of different phasing methods designed for nominally 'unrelated' individuals. We find that SHAPEIT2 produces much lower switch error rates in all cohorts compared to other methods, including those designed specifically for isolated populations. In particular, when large amounts of IBD sharing is present, SHAPEIT2 infers close to perfect haplotypes. Based on these results we have developed a general strategy for phasing cohorts with any level of implicit or explicit relatedness between individuals. First SHAPEIT2 is run ignoring all explicit family information. We then apply a novel HMM method (duoHMM to combine the SHAPEIT2 haplotypes with any family information to infer the inheritance pattern of each meiosis at all sites across each chromosome. This allows the correction of switch errors, detection of recombination events and genotyping errors. We show that the method detects numbers of recombination events that align very well with expectations based on genetic maps, and that it infers far fewer spurious recombination events than Merlin. The method can also detect genotyping errors and infer recombination events in otherwise uninformative families, such as trios and duos. The detected recombination events can be used in association scans for recombination phenotypes. The method provides a simple and unified approach to haplotype estimation, that will be of interest to researchers in the fields of human, animal and plant genetics.

A META-COMPOSITE SOFTWARE DEVELOPMENT APPROACH FOR TRANSLATIONAL RESEARCH

Science.gov (United States)

Sadasivam, Rajani S.; Tanik, Murat M.

2013-01-01

Translational researchers conduct research in a highly data-intensive and continuously changing environment and need to use multiple, disparate tools to achieve their goals. These researchers would greatly benefit from meta-composite software development or the ability to continuously compose and recompose tools together in response to their ever-changing needs. However, the available tools are largely disconnected, and current software approaches are inefficient and ineffective in their support for meta-composite software development. Building on the composite services development approach, the de facto standard for developing integrated software systems, we propose a concept-map and agent-based meta-composite software development approach. A crucial step in composite services development is the modeling of users’ needs as processes, which can then be specified in an executable format for system composition. We have two key innovations. First, our approach allows researchers (who understand their needs best) instead of technicians to take a leadership role in the development of process models, reducing inefficiencies and errors. A second innovation is that our approach also allows for modeling of complex user interactions as part of the process, overcoming the technical limitations of current tools. We demonstrate the feasibility of our approach using a real-world translational research use case. We also present results of usability studies evaluating our approach for future refinements. PMID:23504436

A meta-composite software development approach for translational research.

Science.gov (United States)

Sadasivam, Rajani S; Tanik, Murat M

2013-06-01

Translational researchers conduct research in a highly data-intensive and continuously changing environment and need to use multiple, disparate tools to achieve their goals. These researchers would greatly benefit from meta-composite software development or the ability to continuously compose and recompose tools together in response to their ever-changing needs. However, the available tools are largely disconnected, and current software approaches are inefficient and ineffective in their support for meta-composite software development. Building on the composite services development approach, the de facto standard for developing integrated software systems, we propose a concept-map and agent-based meta-composite software development approach. A crucial step in composite services development is the modeling of users' needs as processes, which can then be specified in an executable format for system composition. We have two key innovations. First, our approach allows researchers (who understand their needs best) instead of technicians to take a leadership role in the development of process models, reducing inefficiencies and errors. A second innovation is that our approach also allows for modeling of complex user interactions as part of the process, overcoming the technical limitations of current tools. We demonstrate the feasibility of our approach using a real-world translational research use case. We also present results of usability studies evaluating our approach for future refinements.

Development of safeguards approach for the Rokkasho Reprocessing Plant

International Nuclear Information System (INIS)

Johnson, S.J.; Abedin-Zadeh, R.; Pearsall, C.; Chesnay, B.; Creusot, C.; Ehinger, M.; Kuhn, E.; Robson, N.; Higuchi, H.; Takeda, S.; Fujimaki, K.; Ai, H.; Uehara, S.; Amano, H.; Hoshi, K.

2001-01-01

Full text: The Rokkasho Reprocessing Plant (RRP), which is currently undergoing construction and commissioning by the Japan Nuclear Fuels Limited (JNFL), is scheduled to begin active operations in 2005. The planned operating capacity is 800 tonnes of spent fuel per year containing approximately 8 tonnes of plutonium. The International Atomic Energy Agency (IAEA) and the Japan safeguards authorities are working with JNFL to develop a Safeguards Approach that is both effective and efficient. In order to accomplish this goal, a number of advanced concepts are being introduced and many currently applied safeguards measures are being enhanced. These new and improved techniques and procedures will provide for more sensitive and reliable verification of nuclear material and facility operations while reducing the required inspection effort. The Safeguards Approach incorporates systematic Design Information Examination and Verification (DIE/DIV) during all phases of construction, commissioning and operation. It incorporates installed, unattended radiation and solution measurement and monitoring systems along with a number of inspector attended measurement systems. While many of the measurement systems will be independent-inspector controlled, others will require authentication of a split signal from operator controlled systems. The independent and/or authenticated data from these systems will be transmitted over a network to a central inspector center for evaluation. Near-Real-Time-Accountancy (NRTA) will be used for short period sequential analysis of the operator and inspector data which, when combined with Solution Monitoring data, will provide higher assurance in the verification of nuclear material for timeliness and of the operational status of the facility. Samples will be taken using a facility installed, but IAEA authenticated, automatic sampling system and will then be transferred to a jointly used IAEA-JSGO On-Site Laboratory (OSL). This paper provides an

Passing the Baton: A Collaborative Approach to Development and Implementation of Context-Specific Modules for Graduate Teaching Assistants in Cognate Disciplines

Science.gov (United States)

O'Neill, Geraldine; McNamara, Martin

2016-01-01

A systematic approach to the training of graduate teaching assistants (GTAs) is required to meet the challenges posed by growing numbers of undergraduate and graduate students. At University College Dublin, educational developers and academic staff across six schools collaborated on the design and phased implementation of context-specific GTA…

A new approach to establish both stable and metastable phase equilibria for fcc ordered/disordered phase transition: application to the Al–Ni and Ni–Si systems

International Nuclear Information System (INIS)

Yuan Xiaoming; Zhang Lijun; Du Yong; Xiong Wei; Tang Ying; Wang Aijun; Liu Shuhong

2012-01-01

Both two-sublattice (2SL) and four-sublattice (4SL) models in the framework of the compound energy formalism can be used to describe the fcc ordered/disordered transitions. When transferring the parameters of 2SL disregarding the metastable ordered states into those of 4SL, inconsistence in either stable or metastable phase diagrams could appear, as detected in both Al–Ni and Ni–Si systems. To avoid such a kind of drawback, this behavior was analyzed and investigated in the Ni–Si and Al–Ni systems with the aid of first–principle calculations. Furthermore, a new approach considering both the stable and metastable fcc ordered phase equilibria deduced from the first–principles calculations was proposed to perform a reliable thermodynamic modeling for the fcc ordered/disordered transition. The Ni–Si system was then thermodynamically assessed using the presently proposed approach. The good agreement between the calculation and experiments demonstrates the reliability of the proposed approach. It is expected that the approach is valid for other systems showing complex ordered/disordered transitions. - Highlights: ► We discuss the drawbacks of order/disorder modeling in the Ni–Si and Al–Ni systems. ► We perform ab initio calculation of thermodynamic properties in the Ni–Si system. ► A CALPHAD–type approach is proposed to model the fcc ordered/disordered transition. ► The Ni–Si system was thermodynamically assessed using the new approach.

Early phase in e-money development: from Edvard Bellamy to Frank Macknamary

Directory of Open Access Journals (Sweden)

O.S. Vysochan

2016-03-01

Full Text Available The article examines the phases of e-money development from the first mentioning of «a credit card» in literary sources to the appearance of Diners Club which preceded modern credit cards. The author has used the historical and geographic method for the decomposition of the early phase in the e-money development concerning the basic motives that induced emitters to develop and implement particular credit-payment systems. The article singles out three stages within the early phase of the e-money development, namely, the beginning of the ХХ-th century (supplying with short-term credits to obtain consumer’s goods, from 1920 to 1940 (guarantee of consumer’s loyalty to a brand, increasing the safety of clearing transactions by payer’s authorization, and 1950-ies (the use of the same credit for payment to various enterprises. It establishes the main features of the early phase in the e-money development; they are such as the absence of the necessary technical supply; emission, sale, guaranty on credits, on the cards issued take place outside the banking system; the lack of corporation credit card segment; the limitation of the application area; the low level of safety of the transactions accomplished.

Exploration on Automated Software Requirement Document Readability Approaches

OpenAIRE

Chen, Mingda; He, Yao

2017-01-01

Context. The requirements analysis phase, as the very beginning of software development process, has been identified as a quite important phase in the software development lifecycle. Software Requirement Specification (SRS) is the output of requirements analysis phase, whose quality factors play an important role in the evaluation work. Readability is a quite important SRS quality factor, but there are few available automated approaches for readability measurement, because of the tight depend...

Multiscale Analysis of Time Irreversibility Based on Phase-Space Reconstruction and Horizontal Visibility Graph Approach

Science.gov (United States)

Zhang, Yongping; Shang, Pengjian; Xiong, Hui; Xia, Jianan

Time irreversibility is an important property of nonequilibrium dynamic systems. A visibility graph approach was recently proposed, and this approach is generally effective to measure time irreversibility of time series. However, its result may be unreliable when dealing with high-dimensional systems. In this work, we consider the joint concept of time irreversibility and adopt the phase-space reconstruction technique to improve this visibility graph approach. Compared with the previous approach, the improved approach gives a more accurate estimate for the irreversibility of time series, and is more effective to distinguish irreversible and reversible stochastic processes. We also use this approach to extract the multiscale irreversibility to account for the multiple inherent dynamics of time series. Finally, we apply the approach to detect the multiscale irreversibility of financial time series, and succeed to distinguish the time of financial crisis and the plateau. In addition, Asian stock indexes away from other indexes are clearly visible in higher time scales. Simulations and real data support the effectiveness of the improved approach when detecting time irreversibility.

Ku Band Phased Array Feed Development for Surface Water Ocean Topography Mission

Data.gov (United States)

National Aeronautics and Space Administration — The purpose of this project is to design components essential to the development of phased arrays and phased array feeds for use in remote sensing. Specifically the...

Development of an Efficient Meso- scale Multi-phase Flow Solver in Nuclear Applications

Energy Technology Data Exchange (ETDEWEB)

Lee, Taehun [City Univ. (CUNY), NY (United States)

2015-10-20

The proposed research aims at formulating a predictive high-order Lattice Boltzmann Equation for multi-phase flows relevant to nuclear energy related application - namely, saturated and sub-cooled boiling in reactors, and liquid- liquid mixing and extraction for fuel cycle separation. An efficient flow solver will be developed based on the Finite Element based Lattice Boltzmann Method (FE- LBM), accounting for phase-change heat transfer and capable of treating multiple phases over length scales from the submicron to the meter. A thermal LBM will be developed in order to handle adjustable Prandtl number, arbitrary specific heat ratio, a wide range of temperature variations, better numerical stability during liquid-vapor phase change, and full thermo-hydrodynamic consistency. Two-phase FE-LBM will be extended to liquid–liquid–gas multi-phase flows for application to high-fidelity simulations building up from the meso-scale up to the equipment sub-component scale. While several relevant applications exist, the initial applications for demonstration of the efficient methods to be developed as part of this project include numerical investigations of Critical Heat Flux (CHF) phenomena in nuclear reactor fuel bundles, and liquid-liquid mixing and interfacial area generation for liquid-liquid separations. In addition, targeted experiments will be conducted for validation of this advanced multi-phase model.

Phase structuring in metal alloys: Ultrasound-assisted top-down approach to engineering of nanostructured catalytic materials.

Science.gov (United States)

Cherepanov, Pavel V; Andreeva, Daria V

2017-03-01

High intensity ultrasound (HIUS) is a novel and efficient tool for top-down nanostructuring of multi-phase metal systems. Ultrasound-assisted structuring of the phase in metal alloys relies on two main mechanisms including interfacial red/ox reactions and temperature driven solid state phase transformations which affect surface composition and morphology of metals. Physical and chemical properties of sonication medium strongly affects the structuring pathways as well as morphology and composition of catalysts. HIUS can serve as a simple, fast, and effective approach for the tuning of structure and surface properties of metal particles, opening the new perspectives in design of robust and efficient catalysts. Copyright © 2016 Elsevier B.V. All rights reserved.

Engineering Work Plan for the Development of Phased Startup Initiative (PSI) Phases 3 and 4 Test Equipment

International Nuclear Information System (INIS)

PITNER, A.L.

2000-01-01

A number of tools and equipment pieces are required to facilitate planned test operations during Phases 3 and 4 of the Phased Startup Initiative (PSI). These items will be used in assessing residual canister sludge quantities on cleaned fuel assemblies, sorting coarse and fine scrap fuel pieces, assessing the size distribution of scrap pieces, loading scrap into a canister, and measuring the depth of the accumulated scrap in a canister. This work plan supercedes those previously issued for development of several of these test items. These items will be considered prototype equipment until testing has confirmed their suitability for use in K West Basin. The process described in AP-EN-6-032 will be used to qualify the equipment for facility use. These items are considered non-OCRWM for PSI Phase 3 applications. The safety classification of this equipment is General Service, with Quality Level 0 (for PSI Phase 3). Quality Control inspections shall be performed to verify basic dimensions and overall configurations of fabricated components, and any special quality control verifications specified in this work plan (Section 3.1.5). These inspections shall serve to approve the test equipment for use in K West Basin (Acceptance Tag). This equipment is for information gathering only during PSI Phases 3 and 4 activities, and will be discarded at the completion of PSI. For equipment needed to support actual production throughput, development/fabrication/testing activities would be more rigorously controlled

Application of the unwrapped phase inversion to land data without source estimation

KAUST Repository

Choi, Yun Seok

2015-08-19

Unwrapped phase inversion with a strong damping was developed to solve the phase wrapping problem in frequency-domain waveform inversion. In this study, we apply the unwrapped phase inversion to band-limited real land data, for which the available minimum frequency is quite high. An important issue of the data is a strong ambiguity of source-ignition time (or source shift) shown in a seismogram. A source-estimation approach does not fully address the issue of source shift, since the velocity model and the source wavelet are updated simultaneously and interact with each other. We suggest a source-independent unwrapped phase inversion approach instead of relying on source-estimation from this land data. In the source-independent approach, the phase of the modeled data converges not to the exact phase value of the observed data, but to the relative phase value (or the trend of phases); thus it has the potential to solve the ambiguity of source-ignition time in a seismogram and work better than the source-estimation approach. Numerical examples show the validation of the source-independent unwrapped phase inversion, especially for land field data having an ambiguity in the source-ignition time.

Development of a Front Tracking Method for Two-Phase Micromixing of Incompressible Viscous Fluids with Interfacial Tension in Solvent Extraction

Energy Technology Data Exchange (ETDEWEB)

Zhou, Yijie [ORNL; Lim, Hyun-Kyung [ORNL; de Almeida, Valmor F [ORNL; Navamita, Ray [State University of New York, Stony Brook; Wang, Shuqiang [State University of New York, Stony Brook; Glimm, James G [ORNL; Li, Xiao-lin [State University of New York, Stony Brook; Jiao, Xiangmin [ORNL

2012-06-01

This progress report describes the development of a front tracking method for the solution of the governing equations of motion for two-phase micromixing of incompressible, viscous, liquid-liquid solvent extraction processes. The ability to compute the detailed local interfacial structure of the mixture allows characterization of the statistical properties of the two-phase mixture in terms of droplets, filaments, and other structures which emerge as a dispersed phase embedded into a continuous phase. Such a statistical picture provides the information needed for building a consistent coarsened model applicable to the entire mixing device. Coarsening is an undertaking for a future mathematical development and is outside the scope of the present work. We present here a method for accurate simulation of the micromixing dynamics of an aqueous and an organic phase exposed to intense centrifugal force and shearing stress. The onset of mixing is the result of the combination of the classical Rayleigh- Taylor and Kelvin-Helmholtz instabilities. A mixing environment that emulates a sector of the annular mixing zone of a centrifugal contactor is used for the mathematical domain. The domain is small enough to allow for resolution of the individual interfacial structures and large enough to allow for an analysis of their statistical distribution of sizes and shapes. A set of accurate algorithms for this application requires an advanced front tracking approach constrained by the incompressibility condition. This research is aimed at designing and implementing these algorithms. We demonstrate verification and convergence results for one-phase and unmixed, two-phase flows. In addition we report on preliminary results for mixed, two-phase flow for realistic operating flow parameters.

Holistic and Ecological Approaches in Talent Development

DEFF Research Database (Denmark)

Henriksen, Kristoffer

the somewhat opposing talent discovery and development approaches by focusing on how an environment manages the balance between these two, and how this balance becomes a part of the environment’s identity. Ecological perspectives on talent development hold rich insights for developing theories, research......Research on athletic talent has evolved from talent detection to talent development with both perspectives focusing on an individual athlete. This individual focus has been mirrored in the applied work of the sport psychology practitioner in youth competitive sport who has primarily focused...... on equipping individual athletes with the psychosocial skills required in a sport career. In contrast, the holistic ecological approach (HEA) to talent development in sport (Henriksen, Stambulova & Roessler, 2010) acknowledges the role of the overall environment in athletes’ development. The HEA integrates...

Development of Michelson interferometer based spatial phase-shift digital shearography

Science.gov (United States)

Xie, Xin

Digital shearography is a non-contact, full field, optical measurement method, which has the capability of directly measuring the gradient of deformation. For high measurement sensitivity, phase evaluation method has to be introduced into digital shearography by phase-shift technique. Catalog by phase-shift method, digital phase-shift shearography can be divided into Temporal Phase-Shift Digital Shearography (TPS-DS) and Spatial Phase-Shift Digital Shearography (SPS-DS). TPS-DS is the most widely used phase-shift shearography system, due to its simple algorithm, easy operation and good phase-map quality. However, the application of TPS-DS is only limited in static/step-by-step loading measurement situation, due to its multi-step shifting process. In order to measure the strain under dynamic/continuous loading situation, a SPS-DS system has to be developed. This dissertation aims to develop a series of Michelson Interferometer based SPS-DS measurement methods to achieve the strain measurement by using only a single pair of speckle pattern images. The Michelson Interferometer based SPS-DS systems utilize special designed optical setup to introduce extra carrier frequency into the laser wavefront. The phase information corresponds to the strain field can be separated on the Fourier domain using a Fourier Transform and can further be evaluated with a Windowed Inverse Fourier Transform. With different optical setups and carrier frequency arrangements, the Michelson Interferometer based SPS-DS method is capable to achieve a variety of measurement tasks using only single pair of speckle pattern images. Catalog by the aimed measurand, these capable measurement tasks can be divided into five categories: 1) measurement of out-of-plane strain field with small shearing amount; 2) measurement of relative out-of-plane deformation field with big shearing amount; 3) simultaneous measurement of relative out-of-plane deformation field and deformation gradient field by using multiple

Neutrino diffusion in the pasta phase matter within the Thomas-Fermi approach

Energy Technology Data Exchange (ETDEWEB)

Furtado, U.J.; Avancini, S.S. [Universidade Federal de Santa Catarina, Departamento de Fisica, CFM, CP. 476, Florianopolis - SC (Brazil); University of Coimbra, CFisUC, Department of Physics, Coimbra (Portugal); Marinelli, J.R.; Martarello, W. [Universidade Federal de Santa Catarina, Departamento de Fisica, CFM, CP. 476, Florianopolis - SC (Brazil); Providencia, C. [University of Coimbra, CFisUC, Department of Physics, Coimbra (Portugal)

2016-09-15

The behaviour and properties of neutrinos in non-uniform nuclear matter, surrounded by electrons and other neutrinos are studied in the protoneutron star early stage characterized by trapped neutrinos. The nuclear matter itself is modelled by a relativistic mean-field approach, and models with both constant couplings and density-dependent couplings are considered. The so-called nuclear pasta phases at sub-saturation densities, described using the Thomas-Fermi approximation and solved in a Wigner-Seitz cell, are included in the calculation. We obtain the neutrino total cross section and mean free path, taking into account scattering and absorption processes and we compare the final results obtained with different parametrizations. The solution for this problem is important for the understanding of neutrino diffusion in a newly born neutron star after a supernovae explosion. It is shown that the pasta phase will increase the neutrino mean free path by as much as an order of magnitude, therefore contributing for shorter emission time-scales. (orig.)

Neutrino diffusion in the pasta phase matter within the Thomas-Fermi approach

International Nuclear Information System (INIS)

Furtado, U.J.; Avancini, S.S.; Marinelli, J.R.; Martarello, W.; Providencia, C.

2016-01-01

The behaviour and properties of neutrinos in non-uniform nuclear matter, surrounded by electrons and other neutrinos are studied in the protoneutron star early stage characterized by trapped neutrinos. The nuclear matter itself is modelled by a relativistic mean-field approach, and models with both constant couplings and density-dependent couplings are considered. The so-called nuclear pasta phases at sub-saturation densities, described using the Thomas-Fermi approximation and solved in a Wigner-Seitz cell, are included in the calculation. We obtain the neutrino total cross section and mean free path, taking into account scattering and absorption processes and we compare the final results obtained with different parametrizations. The solution for this problem is important for the understanding of neutrino diffusion in a newly born neutron star after a supernovae explosion. It is shown that the pasta phase will increase the neutrino mean free path by as much as an order of magnitude, therefore contributing for shorter emission time-scales. (orig.)

A Novel Three Phase to Seven Phase Conversion Technique Using Transformer Winding Connections

Directory of Open Access Journals (Sweden)

M. Tabrez

2017-10-01

Full Text Available This paper proposes a novel multiphase transformer connection scheme which converts three phase balanced AC input to seven phase balanced AC output. Generalized theory to convert a three phase utility supply into any number of phases is presented. Based on the proposed generalized principle, a three phase to seven phase power converting transformer design is presented with connection scheme, analysis and simulation and experimental results of the proposed three phase to seven phase conversion transformer. The proposed transformer in this paper is analyzed and compared with the connection scheme for seven phase available in the literature. The connection scheme is found to have higher power density, lower core area and lower core requirement as compared to the available connection scheme of the same rating. Impedance mismatching between different phases of the transformer is observed in the three phase to seven phase transformer available in the literature. As this mismatching introduces error in study of per phase equivalent circuit diagrams as well as imbalance in voltage and currents. The present design also addresses the impedance mismatching issue and reduces mismatching in the proposed transformer design. A prototype of the proposed system is developed and waveforms are presented. The proposed design is verified using simulation and validated using experimental approach.

The Typology of Methodological Approaches to Development of Innovative Clusters

Directory of Open Access Journals (Sweden)

Farat Olexandra V.

2017-06-01

Full Text Available The aim of the article is to study the existing methodological approaches to assessing the development of enterprises for further substantiation of possibilities of their using by cluster associations. As a result of research, based on the analysis of scientific literature, the most applicable methodological approaches to assessing the development of enterprises are characterized. 8 methodical approaches to assessing the level of development of enterprises and 4 methodological approaches to assessing the level of development of clusters are singled out. Each of the approaches is characterized by the presence of certain advantages and disadvantages, but none of them allows to obtain a systematic assessment of all areas of cluster functioning, identify possible reserves for cluster competitiveness growth and characterize possible strategies for their future development. Taking into account peculiarities of the functioning and development of cluster associations of enterprises, we propose our own methodological approach for assessing the development of innovative cluster structures.

Development of cryogenic free-piston reciprocating expander utilizing phase controller

Energy Technology Data Exchange (ETDEWEB)

Cha, Jeong Min; Park, Ji Ho; Kim, Kyung Joong; Jeong, Sang Kwon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

2016-06-15

A free-piston reciprocating expander is a device which operates without any mechanical linkage to a stationary part. Since the motion of the floating piston is only controlled by the pressure difference at two ends of the piston, this kind of expander may indispensably require a sophisticated active control system equipped with multiple valves and reservoirs. In this paper, we have suggested a novel design that can further reduce complexity of the previously developed cryogenic free-piston expander configuration. It is a simple replacement of both multiple valves and reservoirs by a combination of an orifice valve and a reservoir. The functional characteristic of the integrated orifice-reservoir configuration is similar to that of a phase controller applied in a pulse tube refrigerator so that we designate the one as a phase controller. Depending on the orifice valve size in the phase controller, the different PV work which affects the expander performance is generated. The numerical model of this unique free-piston reciprocating expander utilizing a phase controller is established to understand and analyze quantitatively the performance variation of the expander under different valve timing and orifice valve size. The room temperature experiments are carried out to examine the performance of this newly developed cryogenic expander.

Development of cryogenic free-piston reciprocating expander utilizing phase controller

International Nuclear Information System (INIS)

Cha, Jeong Min; Park, Ji Ho; Kim, Kyung Joong; Jeong, Sang Kwon

2016-01-01

A free-piston reciprocating expander is a device which operates without any mechanical linkage to a stationary part. Since the motion of the floating piston is only controlled by the pressure difference at two ends of the piston, this kind of expander may indispensably require a sophisticated active control system equipped with multiple valves and reservoirs. In this paper, we have suggested a novel design that can further reduce complexity of the previously developed cryogenic free-piston expander configuration. It is a simple replacement of both multiple valves and reservoirs by a combination of an orifice valve and a reservoir. The functional characteristic of the integrated orifice-reservoir configuration is similar to that of a phase controller applied in a pulse tube refrigerator so that we designate the one as a phase controller. Depending on the orifice valve size in the phase controller, the different PV work which affects the expander performance is generated. The numerical model of this unique free-piston reciprocating expander utilizing a phase controller is established to understand and analyze quantitatively the performance variation of the expander under different valve timing and orifice valve size. The room temperature experiments are carried out to examine the performance of this newly developed cryogenic expander

Development and validation of a numerical method for computing two-phase flows without interface reconstruction. Application to Taylor bubbles dynamics

International Nuclear Information System (INIS)

Benkenida, Adlene

1999-01-01

This work is devoted to the development and the use of a numerical code aimed to compute complex two-phase flows in which the topology of the interfaces evolves in time. The solution strategy makes use of a fixed grid on which interfaces evolve freely. The governing equations of the model (one-fluid model) are obtained by adding the local, instantaneous Navier-Stokes equations of each phase after a spatial filtering. The use of an Eulerian approach yields difficulties in estimating several of the two-phase quantities, especially the viscous stress tensor. This problem is overcome by deriving and validating an expression of the stress tensor valid for any Eulerian treatment and whatever the orientation of the interfaces with respect to the grid. To simplify the governing equations of the model, it is assumed that no phase change occurs, that no local slip exists between both phases, and that no small-scale turbulence is present. The possibility to remove some of these hypotheses is discussed, especially with the future aim of developing a large-eddy simulation approach of two-phase flows in which the motion and the effects of small-scale two-phase structures could be taken into account. Interface transport is performed by using a FCT front capturing method without any interface reconstruction procedure. It is shown through several tests that the version of Zalesak's (1979) algorithm in which each direction is treated independently yields the best results, even though a tendency for interfacial regions to thicken artificially is observed in regions with high stretching rates.The code is validated by performing simulations on some simple two-phase flows and by comparing numerical results with available analytical solutions, experiments, or previous computations. Among the results of these tests, those concerning the bouncing of a bubble on a rigid wall are the most original and shed new light on this phenomenon, especially by revealing the time evolution of the

Biomass power for rural development: Phase 2. Technical progress report, April 1--June 30, 1998

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.

1998-11-01

The project undertaken by the Salix Consortium is a multi-phased, multi-partner endeavor. Phase-1 focused on initial development and testing of the technology and agreements necessary to demonstrate commercial willow production in Phase-2. The Phase-1 objectives have been successfully completed: preparing final design plans for two utility pulverized coal boilers, developing fuel supply plans for the project, obtaining power production commitments from the power companies for Phase-2, obtaining construction and environmental permits, and developing an experimental strategy for crop production and power generation improvements needed to assure commercial success. The R and D effort also addresses environmental issues pertaining to introduction of the willow energy system. Beyond those Phase-1 requirements the Consortium has already successfully demonstrated cofiring at Greenidge Station and developed the required nursery capacity for acreage scale-up. This past summer 105 acres were prepared in advance for the spring planting in 1998. Having completed the above tasks, the Consortium is well positioned to begin Phase-2. In phase-2 every aspect of willow production and power generation from willow will be demonstrated. The ultimate objective of Phase-2 is to transition the work performed under the Rural Energy for the Future project into a thriving, self-supported energy crop enterprise.

Municipal solid waste development phases: Evidence from EU27.

Science.gov (United States)

Vujić, Goran; Gonzalez-Roof, Alvaro; Stanisavljević, Nemanja; Ragossnig, Arne M

2015-12-01

Many countries in the European Union (EU) have very developed waste management systems. Some of its members have managed to reduce their landfilled waste to values close to zero during the last decade. Thus, European Union legislation is very stringent regarding waste management for their members and candidate countries, too. This raises the following questions: Is it possible for developing and developed countries to comply with the European Union waste legislation, and under what conditions? How did waste management develop in relation to the economic development in the countries of the European Union? The correlation between waste management practices and economic development was analysed for 27 of the European Union Member States for the time period between 1995 and 2007. In addition, a regression analysis was performed to estimate landfilling of waste in relation to gross domestic product for every country. The results showed a strong correlation between the waste management variables and the gross domestic product of the EU27 members. The definition of the municipal solid waste management development phases followed a closer analysis of the relation between gross domestic product and landfilled waste. The municipal solid waste management phases are characterised by high landfilling rates at low gross domestic product levels, and landfilling rates near zero at high gross domestic product levels. Hence the results emphasize the importance of wider understanding of what is required for developing countries to comply with the European Union initiatives, and highlight the importance of allowing developing countries to make their own paths of waste management development. © The Author(s) 2015.

Stochastic inflation: Quantum phase-space approach

International Nuclear Information System (INIS)

Habib, S.

1992-01-01

In this paper a quantum-mechanical phase-space picture is constructed for coarse-grained free quantum fields in an inflationary universe. The appropriate stochastic quantum Liouville equation is derived. Explicit solutions for the phase-space quantum distribution function are found for the cases of power-law and exponential expansions. The expectation values of dynamical variables with respect to these solutions are compared to the corresponding cutoff regularized field-theoretic results (we do not restrict ourselves only to left-angle Φ 2 right-angle). Fair agreement is found provided the coarse-graining scale is kept within certain limits. By focusing on the full phase-space distribution function rather than a reduced distribution it is shown that the thermodynamic interpretation of the stochastic formalism faces several difficulties (e.g., there is no fluctuation-dissipation theorem). The coarse graining does not guarantee an automatic classical limit as quantum correlations turn out to be crucial in order to get results consistent with standard quantum field theory. Therefore, the method does not by itself constitute an explanation of the quantum to classical transition in the early Universe. In particular, we argue that the stochastic equations do not lead to decoherence

Reflections on Narrative Approaches to Moral Development.

Science.gov (United States)

Lourenco, Orlando

1996-01-01

Compares narrative approaches to Kohlberg's theory of moral development along five dimensions: values relevance, legitimacy, universality, rationality, and commensurability. Argues that, contrary to Kohlberg's theory, narrative approaches may lead to contradiction in epistemology, nihilism in moral choices, and opportunism in relationships.…

Sensitivity analysis of an LCL-filter-based three-phase active rectifier via a virtual circuit approach

DEFF Research Database (Denmark)

Blaabjerg, Frede; Chiarantoni, Ernesto; Aquila, Antonio Dell’

2004-01-01

Three-phase active rectifiers based on the voltage source converter topology can successfully replace traditional thyristor based rectifiers or diode bridge plus chopper in interfacing dc-systems to the grid. However, if the application in which they are employed has a high safety issue......, to the grid side stiffness and to the parameters of the controller has never been detailed considered. In this paper the experimental results of an LCL-filter-based three-phase active rectifier are analysed with the circuit theory approach. A ?virtual circuit? is synthesized in role of the digital controller...

Phase-space densities and effects of resonance decays in a hydrodynamic approach to heavy ion collisions

International Nuclear Information System (INIS)

Akkelin, S.V.; Sinyukov, Yu.M.

2004-01-01

A method allowing analysis of the overpopulation of phase space in heavy ion collisions in a model-independent way is proposed within the hydrodynamic approach. It makes it possible to extract a chemical potential of thermal pions at freeze-out, irrespective of the form of freeze-out (isothermal) hypersurface in Minkowski space and transverse flows on it. The contributions of resonance (with masses up to 2 GeV) decays to spectra, interferometry volumes, and phase-space densities are calculated and discussed in detail. The estimates of average phase-space densities and chemical potentials of thermal pions are obtained for SPS and RHIC energies. They demonstrate that multibosonic phenomena at those energies might be considered as a correction factor rather than as a significant physical effect. The analysis of the evolution of the pion average phase-space density in chemically frozen hadron systems shows that it is almost constant or slightly increases with time while the particle density and phase-space density at each space point decreases rapidly during the system's expansion. We found that, unlike the particle density, the average phase-space density has no direct link to the freeze-out criterion and final thermodynamic parameters, being connected rather to the initial phase-space density of hadronic matter formed in relativistic nucleus-nucleus collisions

New approach for location of continuously emitting acoustic emission sources by phase-controlled probe arrays

International Nuclear Information System (INIS)

Hoeller, P.; Klein, M.; Waschkies, E.; Deuster, G.

1991-01-01

Usually burst-like acoustic emission (AE) is localized by triangulation. For continuous AE, e.g. from leakages, this method is not feasible. Therefore a new method for localization of continuous AE has been developed. It is based on a phase-controlled probe array which consists of many single sensor elements. The AE signals received by the different sensor elements are delayed according to their time-of-flight differences from the source to the single elements of the receiver array. By choosing special combinations of time differences between the array elements the directivity pattern of the sensitivity of the array can be changed, e.g. rotated in the plane of a large plate. Thus, the source direction can be determined by one array. Some preliminary experiments with an artificial noise source, positioned on a large steel plate, have been performed and have demonstrated the feasibility of this approach. (orig.)

Biomass power for rural development. Technical progress report, Phase 2, July 1--September 30, 1998

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.

1999-01-01

The project undertaken by the Salix Consortium is a multi-phased, multi-partner endeavor. Phase 1 focused on initial development and testing of the technology and forging the necessary agreements to demonstrate commercial willow production. The Phase 1 objectives have been successfully completed: preparing final design plans for two utility pulverized coal boiler for 20 MW of biopower capacity; developing fuel supply plans for the project with a goal of establishing 365 ha (900 ac) of willow; obtaining power production commitments from the power companies for Phase 2; obtaining construction and environmental permits; and developing an experimental strategy for crop production and power generation improvements needed to assure commercial success. The R and D effort also addresses environmental issues pertaining to introduction of the willow energy system. Beyond those Phase 1 requirements, the Consortium has already successfully demonstrated cofiring at Greenidge Station and has initiated development of the required nursery capacity for acreage scale-up. In Phase 2 every aspect of willow production and power generation from willow biomass will be demonstrated. The ultimate objective of Phase 2 is to transition the work performed under the Biomass Power for Rural Development project into a thriving, self-supported energy crop enterprise.

Grating-based x-ray differential phase contrast imaging with twin peaks in phase-stepping curves—phase retrieval and dewrapping

Energy Technology Data Exchange (ETDEWEB)

Yang, Yi; Xie, Huiqiao; Tang, Xiangyang, E-mail: xiangyang.tang@emory.edu [Imaging and Medical Physics, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1701 Uppergate Dr., C-5018, Atlanta, Georgia 30322 (United States); Cai, Weixing [Department of Radiation Oncology, Brigham and Women’s Hospital Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115 (United States); Mao, Hui [Laboratory of Functional and Molecular Imaging and Nanomedicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1841 Clifton Road NE, Atlanta, Georgia 30329 (United States)

2016-06-15

Purpose: X-ray differential phase contrast CT implemented with Talbot interferometry employs phase-stepping to extract information of x-ray attenuation, phase shift, and small-angle scattering. Since inaccuracy may exist in the absorption grating G{sub 2} due to an imperfect fabrication, the effective period of G{sub 2} can be as large as twice the nominal period, leading to a phenomenon of twin peaks that differ remarkably in their heights. In this work, the authors investigate how to retrieve and dewrap the phase signal from the phase-stepping curve (PSC) with the feature of twin peaks for x-ray phase contrast imaging. Methods: Based on the paraxial Fresnel–Kirchhoff theory, the analytical formulae to characterize the phenomenon of twin peaks in the PSC are derived. Then an approach to dewrap the retrieved phase signal by jointly using the phases of the first- and second-order Fourier components is proposed. Through an experimental investigation using a prototype x-ray phase contrast imaging system implemented with Talbot interferometry, the authors evaluate and verify the derived analytic formulae and the proposed approach for phase retrieval and dewrapping. Results: According to theoretical analysis, the twin-peak phenomenon in PSC is a consequence of combined effects, including the inaccuracy in absorption grating G{sub 2}, mismatch between phase grating and x-ray source spectrum, and finite size of x-ray tube’s focal spot. The proposed approach is experimentally evaluated by scanning a phantom consisting of organic materials and a lab mouse. The preliminary data show that compared to scanning G{sub 2} over only one single nominal period and correcting the measured phase signal with an intuitive phase dewrapping method that is being used in the field, stepping G{sub 2} over twice its nominal period and dewrapping the measured phase signal with the proposed approach can significantly improve the quality of x-ray differential phase contrast imaging in both

Korea advanced liquid metal reactor development - Development of measuring techniques of the sodium two-phase flow

Energy Technology Data Exchange (ETDEWEB)

Kim, Moo Hwan; Cha, Jae Eun [Pohang University of Science and Technology, Pohang (Korea)

2000-04-01

The technology which models and measures the behavior of bubble in liquid sodium is very important to insure the safety of the liquid metal reactor. In this research, we designed/ manufactured each part and loop of experimental facility for sodium two phase flow, and applied a few possible methods, measured characteristic of two phase flow such as bubbly flow. A air-water loop similar to sodium loop on each measuring condition was designed/manufactured. This air-water loop was utilized to acquire many informations which were necessary in designing the two phase flow of sodium and manufacturing experimental facility. Before the manufacture of a electromagnetic flow meter for sodium, the experiment using each electromagnetic flow mete was developed and the air-water loop was performed to understand flow characteristics. Experiments for observing the signal characteristics of flow were performed by flowing two phase mixture into the electromagnetic flow mete. From these experiments, the electromagnetic flow meter was designed and constructed by virtual electrode, its signal processing circuit and micro electro magnet. It was developed to be applicable to low conductivity fluid very successfully. By this experiment with the electromagnetic flow meter, we observed that the flow signal was very different according to void fraction in two phase flow and that probability density function which was made by statistical signal treatment is also different according to flow patterns. From this result, we confirmed that the electromagnetic flow meter could be used to understand the parameters of two phase flow of sodium. By this study, the experimental facility for two phase flow of sodium was constricted. Also the new electromagnetic flow meter was designed/manufactured, and experimental apparatus for two phase flow of air-water. Finally, this study will be a basic tool for measurement of two phase flow of sodium. As the fundamental technique for the applications of sodium at

METHODOLOGICAL APPROACHES FOR MODELING THE RURAL SETTLEMENT DEVELOPMENT

Directory of Open Access Journals (Sweden)

Gorbenkova Elena Vladimirovna

2017-10-01

Full Text Available Subject: the paper describes the research results on validation of a rural settlement developmental model. The basic methods and approaches for solving the problem of assessment of the urban and rural settlement development efficiency are considered. Research objectives: determination of methodological approaches to modeling and creating a model for the development of rural settlements. Materials and methods: domestic and foreign experience in modeling the territorial development of urban and rural settlements and settlement structures was generalized. The motivation for using the Pentagon-model for solving similar problems was demonstrated. Based on a systematic analysis of existing development models of urban and rural settlements as well as the authors-developed method for assessing the level of agro-towns development, the systems/factors that are necessary for a rural settlement sustainable development are identified. Results: we created the rural development model which consists of five major systems that include critical factors essential for achieving a sustainable development of a settlement system: ecological system, economic system, administrative system, anthropogenic (physical system and social system (supra-structure. The methodological approaches for creating an evaluation model of rural settlements development were revealed; the basic motivating factors that provide interrelations of systems were determined; the critical factors for each subsystem were identified and substantiated. Such an approach was justified by the composition of tasks for territorial planning of the local and state administration levels. The feasibility of applying the basic Pentagon-model, which was successfully used for solving the analogous problems of sustainable development, was shown. Conclusions: the resulting model can be used for identifying and substantiating the critical factors for rural sustainable development and also become the basis of

Sampling phased array a new technique for signal processing and ultrasonic imaging

OpenAIRE

Bulavinov, A.; Joneit, D.; Kröning, M.; Bernus, L.; Dalichow, M.H.; Reddy, K.M.

2006-01-01

Different signal processing and image reconstruction techniques are applied in ultrasonic non-destructive material evaluation. In recent years, rapid development in the fields of microelectronics and computer engineering lead to wide application of phased array systems. A new phased array technique, called "Sampling Phased Array" has been developed in Fraunhofer Institute for non-destructive testing. It realizes unique approach of measurement and processing of ultrasonic signals. The sampling...

Frequency domain phase retrieval of simultaneous multi-wavelength phase-shifting interferometry

International Nuclear Information System (INIS)

Yin, Zhenxing; Zhong, Liyun; Xu, Xiaofei; Zhang, Wangping; Lu, Xiaoxu; Tian, Jindong

2016-01-01

In simultaneous multi-wavelength phase-shifting interferometry, we propose a novel frequency domain phase retrieval (FDPR) algorithm. First, using only a one-time phase-shifting operation, a sequence of simultaneous multi-wavelength phase-shifting interferograms (SPSMWIs) are captured by a monochrome charge-coupled device. Second, by performing a Fourier transform for each pixel of SPSMWIs, the wrapped phases of each wavelength can be retrieved from the complex amplitude located in the spectral peak of each wavelength. Finally, the phase of the synthetic wavelength can be obtained by the subtraction between the wrapped phases of a single wavelength. In this study, the principle and the application condition of the proposed approach are discussed. Both the simulation and the experimental result demonstrate the simple and convenient performance of the proposed FDPR approach. (paper)

Systems approach to waste management in developing countries

International Nuclear Information System (INIS)

Johnson, E. R.

1991-01-01

A systems engineering approach to the development of waste management facilities is described which may prove to be useful for developing countries. Basically the approach involves a determination of performance objectives, the functions necessary to achieve the objectives, the constraints involved, and the basic facility requirements necessary to accomplish the functions. The foregoing provides the basis for developing a set of descriptions and associated requirements for the overall system as well as for elements of the system at different hierarchical levels. These in turn provide the basis for initiation of design and subsequently construction of the facilities involved. The operation of the approach is illustrated for a hypothetical low level waste processing system

Possible approaches to community development for nuclear waste isolation

International Nuclear Information System (INIS)

Voth, D.E.; Herrington, B.E.

1982-10-01

Community development is a process whereby communities assess their needs, determine their priorities, make plans, carry out these plans, and evaluate the results. This approach is applied in evaluating four possible decision-making scenarios that DOE could use in the site selection process and in the development of compensation/mitigation mechanisms. In the first scenario, DOE would select the repository site purely on geologic and technological grounds. In the second scenario, DOE would select the repository site using geologic and technological information, detailed socioeconomic information, and an understanding of potential socioeconomic impacts of a nuclear repository upon the community. In the third scenario DOE would select a repository site using the same information available in the second scenario; however, in this case, DOE would provide the local community with professionals who would act as advocates for the local community and argue their position within DOE's decision-making process. In the final scenario, DOE would invite potential repository site communities to engage in an auctioning process, whereby each community would bid on an acceptable compensation package (in their eyes) to be paid by DOE. Based on an evaluation of these scenarios, the report makes the following recommendations: (1) DOE should consider the auctioning process; (2) in the event that no communities are willing to present bids, DOE should provide communities with advocates; (3) compensation should be a collective package rather than in the form of individual cash payments; (4) a third party (other than DOE), with a heavy reliance on local organizations, should be specifically created for implementing the compensation/mitigation package; and (5) in order to approach the siting of additional repositories with greater understanding, longitudinal research at the first repository should be undertaken as a part of the monitoring phase

Promoting energy-saving and environmentally friendly generation dispatching model in China: Phase development and case studies

International Nuclear Information System (INIS)

Ding, Yi; Yang, Hongliang

2013-01-01

Energy saving and environmental protection are important conditions for the sustainable development of Chinese economy. However current widely used generation scheduling model based on predefined production quota and tariff results in heavy energy consumption and severe environment pollution. From 2007, as concerns over energy shortage and environmental pollution, the Chinese authorities introduced the implementation of energy-saving generation dispatching model, which is an important approach to facilitating energy-saving and reduction of pollutant emission. The objective of implementing energy-saving generation dispatching model is to prioritize the use of renewable energy resources and new power plants with high efficiency without compromising power system security and reliability. This paper analyzes the necessity and feasibility of implementing energy-efficient and environmentally friendly generation scheduling models in China. The institutional and technical barriers impeding the implementation of energy-saving generation dispatching model are identified. The development of advanced energy-saving generation scheduling models towards competitive market models and phased planning programs are emphasized in this paper. The effectiveness and experience of provinces piloted energy-saving generation dispatching projects are also discussed. - Highlights: ► Introducing problems of current power generation scheduling model in China. ► Discussing necessity of implementing ESGD model and corresponding barriers. ► Proposing phased planning programs for developing ESGD models. ► Discussing the effectiveness and experience of provinces piloted ESGD projects

Continued development of a semianalytical solution for two-phase fluid and heat flow in a porous medium

Energy Technology Data Exchange (ETDEWEB)

Doughty, C.; Pruess, K. [Lawrence Berkeley Lab., CA (United States)

1991-06-01

Over the past few years the authors have developed a semianalytical solution for transient two-phase water, air, and heat flow in a porous medium surrounding a constant-strength linear heat source, using a similarity variable {eta} = r/{radical}t. Although the similarity transformation approach requires a simplified geometry, all the complex physical mechanisms involved in coupled two-phase fluid and heat flow can be taken into account in a rigorous way, so that the solution may be applied to a variety of problems of current interest. The work was motivated by adverse to predict the thermohydrological response to the proposed geologic repository for heat-generating high-level nuclear wastes at Yucca Mountain, Nevada, in a partially saturated, highly fractured volcanic formation. The paper describes thermal and hydrologic conditions near the heat source; new features of the model; vapor pressure lowering; and the effective-continuum representation of a fractured/porous medium.

Approach to performance based regulation development

International Nuclear Information System (INIS)

Spogen, L.R.; Cleland, L.L.

1977-06-01

An approach to the development of performance based regulations (PBR's) is described. Initially, a framework is constructed that consists of a function hierarchy and associated measures. The function at the top of the hierarchy is described in terms of societal objectives. Decomposition of this function into subordinate functions and their subsequent decompositions yield the function hierarchy. ''Bottom'' functions describe the roles of system components. When measures are identified for the performance of each function and means of aggregating performances to higher levels are established, the framework may be employed for developing PBR's. Consideration of system flexibility and performance uncertainty guide in determining the hierarchical level at which regulations are formulated. Ease of testing compliance is also a factor. To show the viability of the approach, the framework developed by Lawrence Livermore Laboratory for the Nuclear Regulatory Commission for evaluation of material control systems at fixed facilities is presented

Renormalization group approach to QCD phase transitions

International Nuclear Information System (INIS)

Midorikawa, S.; Yoshimoto, S.; So, H.

1987-01-01

Effective scalar theories for QCD are proposed to investigate the deconfining and chiral phase transitions. The orders of the phase transitions are determined by infrared stabilities of the fixed points. It is found that the transitions in SU(3) gauge theories are of 1st order for any number of massless flavors. The cases of SU(2) and SU(4) gauge theories are also discussed. (orig.)

Architecture Approach in System Development

Directory of Open Access Journals (Sweden)

Ladislav Burita

2017-01-01

Full Text Available The purpose of this paper is to describe a practical solution of architecture approach in system development. The software application is the system which optimizes the transport service. The first part of the paper defines the enterprise architecture, its parts and frameworks. Next is explained the NATO Architecture Framework (NAF, a tool for command and control systems development in military environment. The NAF is used for architecture design of the system for optimization of the transport service.

Prevention of MSD by means of ergonomic risk assessment (tools) in all phases of the vehicle development process.

Science.gov (United States)

Karlheinz, Schaub; Michaela, Kugler; Max, Bierwirth; Andrea, Sinn-Behrendt; Ralph, Bruder

2012-01-01

In industrialized countries musculoskeletal disorders (MSD) play an import role and are often responsible for almost one third of the total sick leave. The changes in the demographic profiles, i.e. aging work forces might even worsen this situation in the future. For a highly productive and sustainable use of human resources in production systems, ergonomics offers high potentials. In the recent years the authors have developed several ergonomic risk assessment tools, especially for the use in automotive industries. These methods may be used during the planning phases in the Tech Centers as well as during the production phase at shop floor level. The tools might also be used for a standardized communication in between the Tech Center and the plants to improve the effects of "lessons learned" for the design and layout of workstations and processes and the optimization of vehicle components. This paper describes suitable risk assessment tools as well as the integration of these tools into the vehicle development process. It introduces a comprehensive management approach for the integration of ergonomics into the management of production systems.

A Task-Based Approach to Materials Development

Science.gov (United States)

Nunan, David

2010-01-01

The purpose of this chapter is to present a task-based approach to materials development. In the first part of the chapter, I sketch out the evolution of task based language teaching, drawing on a distinction between synthetic and analytical approaches to syllabus design first articulated by Wilkins (1976).

Simulation Approach to Mission Risk and Reliability Analysis, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — It is proposed to develop and demonstrate an integrated total-system risk and reliability analysis approach that is based on dynamic, probabilistic simulation. This...

Enginnering development of coal-fired high performance power systems phase II and III

International Nuclear Information System (INIS)

1998-01-01

This report presents work carried out under contract DE-AC22-95PC95144 ''Engineering Development of Coal-Fired High Performance Systems Phase II and III.'' The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) that is capable of: thermal efficiency (HHV) >47%; NOx, SOx, and particulates 65% of heat input; all solid wastes benign; cost of electricity <90% of present plants. Phase I, which began in 1992, focused on the analysis of various configurations of indirectly fired cycles and on technical assessments of alternative plant subsystems and components, including performance requirements, developmental status, design options, complexity and reliability, and capital and operating costs. Phase I also included preliminary R ampersand D and the preparation of designs for HIPPS commercial plants approximately 300 MWe in size. This phase, Phase II, involves the development and testing of plant subsystems, refinement and updating of the HIPPS commercial plant design, and the site selection and engineering design of a HIPPS prototype plant. Work reported herein is from: Task 2.2 HITAF Air Heaters; Task 6 HIPPS Commercial Plant Design Update

Toward a More Holistic Evaluation Approach for Rural Development

Science.gov (United States)

Miyoshi, Koichi

2013-01-01

The discussion on and development of a holistic evaluation approach for rural development will be indispensable to improving and enriching the lives of rural people. This approach can be developed by considering the conceptualization of community policy structure in rural areas, the localization of policy structure in the rural community, and the…

Stepwise Approach to Accessible MOOC Development.

Science.gov (United States)

Draffan, E A; Wald, Mike; Dickens, Kate; Zimmermann, Gottfried; Kelle, Sebastian; Miesenberger, Klaus; Petz, Andrea

2015-01-01

Developing resources for online learning in its many guises and more recently for MOOCs has been discussed across the educational sector, usually by individuals working for one institution or organisation. Rarely are there discussions that highlight the issues of collaborative working on content that is delivered over a period of weeks for a wide range of abilities and skills. In particular there is a reluctance to face the issues presented by barriers to access for those with disabilities and even the issues that could arise should an academic be unable to access the development platform to present content. This paper aims to approach these issues by providing guidance in a series of practical steps that highlight an inclusive design approach.

Isotropic differential phase contrast microscopy for quantitative phase bio-imaging.

Science.gov (United States)

Chen, Hsi-Hsun; Lin, Yu-Zi; Luo, Yuan

2018-05-16

Quantitative phase imaging (QPI) has been investigated to retrieve optical phase information of an object and applied to biological microscopy and related medical studies. In recent examples, differential phase contrast (DPC) microscopy can recover phase image of thin sample under multi-axis intensity measurements in wide-field scheme. Unlike conventional DPC, based on theoretical approach under partially coherent condition, we propose a new method to achieve isotropic differential phase contrast (iDPC) with high accuracy and stability for phase recovery in simple and high-speed fashion. The iDPC is simply implemented with a partially coherent microscopy and a programmable thin-film transistor (TFT) shield to digitally modulate structured illumination patterns for QPI. In this article, simulation results show consistency of our theoretical approach for iDPC under partial coherence. In addition, we further demonstrate experiments of quantitative phase images of a standard micro-lens array, as well as label-free live human cell samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relationship between phase development and swelling of AISI 316 during temperature changes

International Nuclear Information System (INIS)

Yang, W.J.S.; Garner, F.A.

1982-04-01

The effect of temperature changes on radiation-induced swelling and phase development of AISI 316 has been examined for specimens irradiated in two different experiments. The formation of radiation-stable phases at low temperature appears to precede swelling but these phases tend to dissolve when subsequently subjected to higher temperature. Phases which develop at high temperature persist when the temperature is subsequently lowered. Once nucleated at low temperatures, voids tend to persist without reduction in density at higher temperatures. However, a new round of void nucleation occurs when the temperature is decreased during irradiation. If the swelling has entered the steady-state swelling regime prior to the temperature change, there is no effect on the subsequent swelling rate. For temperature changes that occur before the end of the transient swelling regime, substantial changes can occur in the swelling behavior, particularly if the changes occur in the range around 500 0 . The isothermal swelling behavior of AISI 316 is much less sensitive to irradiation temperature than previously envisioned

Development and validation of a reversed phase High Performance ...

African Journals Online (AJOL)

A simple, rapid, accurate and economical isocratic Reversed Phase High Performance Liquid Chromatography (RPHPLC) method was developed, validated and used for the evaluation of content of different brands of paracetamol tablets. The method was validated according to ICH guidelines and may be adopted for the ...

Numerical simulation of two-phase flow with front-capturing

International Nuclear Information System (INIS)

Tzanos, C.P.; Weber, D.P.

2000-01-01

Because of the complexity of two-phase flow phenomena, two-phase flow codes rely heavily on empirical correlations. This approach has a number of serious shortcomings. Advances in parallel computing and continuing improvements in computer speed and memory have stimulated the development of numerical simulation tools that rely less on empirical correlations and more on fundamental physics. The objective of this work is to take advantage of developments in massively parallel computing, single-phase computational fluid dynamics of complex systems, and numerical methods for front capturing in two-phase flows to develop a computer code for direct numerical simulation of two-phase flow. This includes bubble/droplet transport, interface deformation and topology change, bubble-droplet interactions, interface mass, momentum, and energy transfer. In this work, the Navier-Stokes and energy equations are solved by treating both phases as a single fluid with interfaces between the two phases, and a discontinuity in material properties across the moving interfaces. The evolution of the interfaces is simulated by using the front capturing technique of the level-set methods. In these methods, the boundary of a two-fluid interface is modeled as the zero level set of a smooth function φ. The level-set function φ is defined as the signed distance from the interface (φ is negative inside a droplet/bubble and positive outside). Compared to other front-capturing or front-tracking methods, the level-set approach is relatively easy to implement even in three-dimensional flows, and it has been shown to simulate well the coalescence and breakup of droplets/bubbles

Enhanced field emission from PbTiO{sub 3} nanodots prepared by phase separation approach

Energy Technology Data Exchange (ETDEWEB)

Li Jinna; Luo Ming [Department of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Weng Wenjian, E-mail: wengwj@zju.edu.cn [Department of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Cheng Kui; Du Piyi; Shen Ge; Han Gaorong [Department of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)

2009-10-15

Uniformly distributed PbTiO{sub 3} nanodots were successfully prepared by phase separation approach. A precursor sol film was first spin-coated on Si wafer and then spontaneously separated into two distinct phases owing to the Marangoni instability. PT nanodots with tailorable size and density were obtained after further heat treatment. X-ray diffraction analysis indicated that these nanodots showed a perovskite structure. An excellent room temperature field emission property of PbTiO{sub 3} nanodots was observed: the minimum turn-on voltage was about 5.3 V/{mu}m; while the emission current density reached about 270 {mu}A cm{sup -2} at an applied field of about 9.25 V/{mu}m.

New approaches for the analysis of confluent cell layers with quantitative phase digital holographic microscopy

Science.gov (United States)

Pohl, L.; Kaiser, M.; Ketelhut, S.; Pereira, S.; Goycoolea, F.; Kemper, Björn

2016-03-01

Digital holographic microscopy (DHM) enables high resolution non-destructive inspection of technical surfaces and minimally-invasive label-free live cell imaging. However, the analysis of confluent cell layers represents a challenge as quantitative DHM phase images in this case do not provide sufficient information for image segmentation, determination of the cellular dry mass or calculation of the cell thickness. We present novel strategies for the analysis of confluent cell layers with quantitative DHM phase contrast utilizing a histogram based-evaluation procedure. The applicability of our approach is illustrated by quantification of drug induced cell morphology changes and it is shown that the method is capable to quantify reliable global morphology changes of confluent cell layers.

A Multidisciplinary Approach to Decommissioning Offshore Wells Using Stakeholder Engagement, Risk Identification, and the United Nations Sustainable Development Goals

Science.gov (United States)

Battalora, L.; Prasad, M.

2017-12-01

Context/PurposeThe typical oil and gas project lifecycle includes acquisition, exploration, drilling, production, and decommissioning phases. The oil and gas industry (Industry) has become proactive in identifying and mitigating health, safety, security, environment, and social responsibility risks during these phases as well as designing for sustainable development. With many fields reaching the end stages of the lifecycle, Industry is faced with the challenge of identifying and evaluating risks in the decommissioning phase. The level of challenge is increased when planning for the decommissioning of offshore wells. This paper describes tools that can be applied in the multidisciplinary design of the decommissioning program including use of the United Nations Sustainable Development Goals (SDGs). MethodsStakeholder engagement is key to a successful project. Typical stakeholders in an oil and gas project include the community, regulatory agencies, federal, state, and local governments, private investors, academia, and non-governmental organizations. Before engagement begins, stakeholders must be identified as well as their level of influence in the project. Relationships between stakeholders are "mapped" providing a better understanding of priorities and areas of concentration. Project risks are identified and ranked according to likelihood and impact. Mitigations are matched to risks. Sustainable development is implemented through acknowledgement of societal, economic, and environmental impacts in engineering design. InterpretationRecently, the United Nations Development Programme (UNDP), the International Finance Corporation (IFC) and IPIECA, the global oil and gas industry association for environmental and social issues, partnered to develop the publication, Mapping the oil and gas industry to the Sustainable Development Goals: An Atlas. SDGs have been linked to Industry operations and can serve as a guide for the offshore decommissioning phase Conclusion

Top-Down Approach for the Social Capital Development

OpenAIRE

Shah, Syed Akhter Hussain; Shah, Tari shah; Ahmed, Eatzaz

2011-01-01

This study provides the compatibility of top-down approach of the collectivist society with the algebraic representation of social capital matrix [22], which establishes algebraic based model having capability of interpreting the state intervention in building social capital. The study also suggests a policy framework for the developing economic strategies and effective planing at government level regarding social capital development in perspective of top-down approach.

Design and Development of Gas-Liquid Cylindrical Cyclone Compact Separators for Three-Phase Flow; SEMIANNUAL

International Nuclear Information System (INIS)

Mohan, Ram S.; Shoham, Ovadia

1999-01-01

The objective of this five-year project (October, 1997-September, 2002) is to expand the current research activities of Tulsa University Separation Technology Projects (TUSTP) to multiphase oil/water/gas separation. This project will be executed in two phases. Phase I (1997-2000) will focus on the investigations of the complex multiphase hydrodynamic flow behavior in a three-phase Gas-Liquid Cylindrical Cyclone (GLCC) Separator. The activities of this phase will include the development of a mechanistic model, a computational fluid dynamics (CFD) simulator, and detailed experimentation on the three-phase GLCC. The experimental and CFD simulation results will be suitably integrated with the mechanistic model. In Phase II (2000-2002), the developed GLCC separator will be tested under high pressure and real crudes conditions. This is crucial for validating the GLCC design for field application and facilitating easy and rapid technology deployment. Design criteria for industrial applications will be developed based on these results and will be incorporated into the mechanistic model by TUSTP

An alternative approach in operator allocation labor intensive manufacturing system: A three-phase methodology framework

Science.gov (United States)

Mat Rani, Ruzanita; Ismail, Wan Rosmanira

2013-04-01

Operator allocation is one of the most important decisions that can affect productivity in labor-intensive manufacturing system. Improper decision on operator allocation will reduce company's throughput and increase waste. Therefore, all factors such as operators' performance and operational constraints need to be considered in making the best operator allocation decision. Most of previous studies used two phases methodology. In two phases methodology, they used operational constraints and treated all operators to have the same level of performance for making decision on operator allocation. Therefore, in this paper a three-phase methodology is proposed to determine the optimal operator allocation. This methodology advances the existing approach on operator allocation by combining operators' performance and operational constraints. The methodology starts with evaluating the operators' performance. Then, it is followed with determining inputs and outputs for operator allocation alternatives and it ends with determining the optimal operator allocation. This paper will give ideas and directions to the management of the manufacturing company in determining the optimal operator allocation decision.

Genome-Wide Approaches to Drosophila Heart Development

Directory of Open Access Journals (Sweden)

Manfred Frasch

2016-05-01

Full Text Available The development of the dorsal vessel in Drosophila is one of the first systems in which key mechanisms regulating cardiogenesis have been defined in great detail at the genetic and molecular level. Due to evolutionary conservation, these findings have also provided major inputs into studies of cardiogenesis in vertebrates. Many of the major components that control Drosophila cardiogenesis were discovered based on candidate gene approaches and their functions were defined by employing the outstanding genetic tools and molecular techniques available in this system. More recently, approaches have been taken that aim to interrogate the entire genome in order to identify novel components and describe genomic features that are pertinent to the regulation of heart development. Apart from classical forward genetic screens, the availability of the thoroughly annotated Drosophila genome sequence made new genome-wide approaches possible, which include the generation of massive numbers of RNA interference (RNAi reagents that were used in forward genetic screens, as well as studies of the transcriptomes and proteomes of the developing heart under normal and experimentally manipulated conditions. Moreover, genome-wide chromatin immunoprecipitation experiments have been performed with the aim to define the full set of genomic binding sites of the major cardiogenic transcription factors, their relevant target genes, and a more complete picture of the regulatory network that drives cardiogenesis. This review will give an overview on these genome-wide approaches to Drosophila heart development and on computational analyses of the obtained information that ultimately aim to provide a description of this process at the systems level.

Direction of Technology Development for Nuclear Power Plants at the O and M Phase

Energy Technology Data Exchange (ETDEWEB)

Jung, Insu; Park, Hwanpyo; Kim, Younghyun [Korea Institute of Construction Technology, Goyang (Korea, Republic of)

2014-05-15

Recently, Korea has attempted to advance overseas markets by securing competitive power in nuclear power technology. In order to develop and operate overall construction management systems with Korea's own brand equipped with sufficient applicability and competitive power in the market abroad and to ensure equal competitive power with other foreign advanced companies of nuclear power plants, Korea has launched a project called 'Data Centric Integration/Automation Technology for NP Project Management System' since July 2011. This project is divided into two phases: the first phase from 2012 to 2016 realizes EPCS stage, and the second phase from 2017 to 2020 extends to O and M stage. Appropriate technology development planning must be established if 'Data Centric Integration/Automation Technology for NP Project Management System' conducted at the first phase would extend to O and M stage at the second phase. Therefore, this study aimed at drawing out the direction of technology development based on present analysis of process at the operational phase of nuclear power plants in Korea conducted as previous study. This study analyzed current operation and maintenance systems first, analyzing the results of differences between the operation process of nuclear plants in Korea which was suggested at the previous study and the process of the Korea Hydro and Nuclear Power Co., Ltd. (hereafter referred to as 'KHNP') and drawing out the direction of technology development for nuclear power plants at the operational phase from the viewpoint of life cycle.

Direction of Technology Development for Nuclear Power Plants at the O and M Phase

International Nuclear Information System (INIS)

Jung, Insu; Park, Hwanpyo; Kim, Younghyun

2014-01-01

Recently, Korea has attempted to advance overseas markets by securing competitive power in nuclear power technology. In order to develop and operate overall construction management systems with Korea's own brand equipped with sufficient applicability and competitive power in the market abroad and to ensure equal competitive power with other foreign advanced companies of nuclear power plants, Korea has launched a project called 'Data Centric Integration/Automation Technology for NP Project Management System' since July 2011. This project is divided into two phases: the first phase from 2012 to 2016 realizes EPCS stage, and the second phase from 2017 to 2020 extends to O and M stage. Appropriate technology development planning must be established if 'Data Centric Integration/Automation Technology for NP Project Management System' conducted at the first phase would extend to O and M stage at the second phase. Therefore, this study aimed at drawing out the direction of technology development based on present analysis of process at the operational phase of nuclear power plants in Korea conducted as previous study. This study analyzed current operation and maintenance systems first, analyzing the results of differences between the operation process of nuclear plants in Korea which was suggested at the previous study and the process of the Korea Hydro and Nuclear Power Co., Ltd. (hereafter referred to as 'KHNP') and drawing out the direction of technology development for nuclear power plants at the operational phase from the viewpoint of life cycle

Phase development and kinetics of high temperature Bi-2223 phase

International Nuclear Information System (INIS)

Yavuz, M.; Maeda, H.; Hua, K.L.; Shi, X.D.

1998-01-01

The two-dimensional nucleation (random)-growth mechanism were observed as a support for the related previous works, which is attributable to the growth of the Bi-2223 grain in the a-b plane direction of the Bi-2212 matrix is being much faster than in the c-direction, or that the early-formed plate-like 2212 phase confines the 2223 product. At the beginning of the reaction, the additional phases are partially melted. Because of the structure, composition and thermal fluctuation, the 2223 nucleates and grows in the phase boundary between the liquid phase and Bi-2212. It was shown here that the nucleation and the growth rate were relatively fast between 0 and 36 h. At the final stage, between 36 and 60 h, because of the impingement of the growth fronts of different nuclei, the high formation rate of 2223 is suppressed. The major reactant 2212 remains as a solid and its plate-like configuration determines the two dimensional nature of the reaction. The amount of liquid forms during reaction is small. (orig.)

A Formal Approach to User Interface Design Using Hybrid System Theory, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Based upon the feasibility demonstrated in the Phase I research, Optimal Synthesis Inc.(OSI) proposes to develop a software tool that can be used validate aircraft...

Policy development: a more formal systems approach process

CSIR Research Space (South Africa)

Greeff, AP

2011-09-01

Full Text Available Policy developers in corporate and governance roles are often developing policies by means of policy development cycles that typically resemble a system life cycle approach. Although policy development cycles often vary, depending on the applicable...

A group-based approach to stabilisation and symptom management in a phased treatment model for refugees and asylum seekers

Directory of Open Access Journals (Sweden)

Mary E. A. Robertson

2013-12-01

Full Text Available Background: Traumatised asylum seekers and refugees may present with significant and complex mental health problems as a result of prolonged, extreme, and multiple traumatic events. This is further complicated by ongoing complex social circumstances. Concepts: In our work at the Traumatic Stress Clinic (TSC, the understanding afforded by the concept of complex posttraumatic stress disorder (PTSD together with the related notion of a phased treatment model, provides a useful framework for organising our work with this population. Clinical Applications: An explication of complex PTSD as it applies to our client group is presented, followed by a description of our phased treatment model and an outline of the core principles, which guide our clinical approach. Our symptom management and stabilisation groups have been developed and refined over time and draw on techniques from a variety of cognitive behavioural therapies. These are described in some detail with illustrative clinical case vignettes. Conclusion: This paper concludes with some reflections on the challenges inherent to working with this complex client group.

Usefulness of acute phase proteins for monitoring development of ...

African Journals Online (AJOL)

Background: Serum levels of acute phase proteins (APP) have been used to diagnose and follow up treatment of liver diseases. This study was carried out to determine the usefulness of APP to predict development of hepatocellular carcinoma (HCC) among Hepatitis B virus (HBV) carriers. Study design: In a prospective ...

Enhanced deterministic phase retrieval using a partially developed speckle field

DEFF Research Database (Denmark)

Almoro, Percival F.; Waller, Laura; Agour, Mostafa

2012-01-01

A technique for enhanced deterministic phase retrieval using a partially developed speckle field (PDSF) and a spatial light modulator (SLM) is demonstrated experimentally. A smooth test wavefront impinges on a phase diffuser, forming a PDSF that is directed to a 4f setup. Two defocused speckle...... intensity measurements are recorded at the output plane corresponding to axially-propagated representations of the PDSF in the input plane. The speckle intensity measurements are then used in a conventional transport of intensity equation (TIE) to reconstruct directly the test wavefront. The PDSF in our...

Phase shift effects for fluid conveying pipes with non-ideal supports

DEFF Research Database (Denmark)

Dahl, Jonas; Thomsen, Jon Juel

2008-01-01

Vibrations of a fluid-conveying pipe with non-ideal supports are investigated with respect to phase shift effects. A numerical Galerkin approach is developed for this general problem, and the use of it exemplified with a investigation of phase shift effects from rotational damping at supports...

Designing a strategic plan development approach for integrated area development projects

NARCIS (Netherlands)

de Kort, Inge

2009-01-01

Increasingly, it has become evident that spatial problems can no longer be resolved in isolation, but should be solved in conjunction with other development-related issues. Interest in integrated area development is growing, and a more integrated planning approach is desired. In this design-based

A relational developmental systems approach to moral development.

Science.gov (United States)

Carpendale, Jeremy I M; Hammond, Stuart I; Atwood, Sherrie

2013-01-01

Morality and cooperation are central to human life. Psychological explanations for moral development and cooperative behavior will have biological and evolutionary dimensions, but they can differ radically in their approach to biology. In particular, many recent proposals have pursued the view that aspects of morality are innate. We briefly review and critique two of these claims. In contrast to these nativist assumptions about the role of biology in morality, we present an alternative approach based on a relational developmental systems view of moral development. The role for biology in this approach is in setting up the conditions--the developmental system--in which forms of interaction and later forms of thinking emerge.

Environmental impact assessment of a package type IFAS reactor during construction and operational phases: a life cycle approach.

Science.gov (United States)

Singh, Nitin Kumar; Singh, Rana Pratap; Kazmi, Absar Ahmad

2017-05-01

In the present study, a life cycle assessment (LCA) approach was used to analyse the environmental impacts associated with the construction and operational phases of an integrated fixed-film activated sludge (IFAS) reactor treating municipal wastewater. This study was conducted within the boundaries of a research project that aimed to investigate the implementation related challenges of a package type IFAS reactor from an environmental perspective. Along with the LCA results of the construction phase, a comparison of the LCA results of seven operational phases is also presented in this study. The results showed that among all the inputs, the use of stainless steel in the construction phase caused the highest impact on environment, followed by electricity consumption in raw materials production. The impact of the construction phase on toxicity impact indicators was found to be significant compared to all operational phases. Among the seven operational phases of this study, the dissolved oxygen phase III, having a concentration of ∼4.5 mg/L, showed the highest impact on abiotic depletion, acidification, global warming, ozone layer depletion, human toxicity, fresh water eco-toxicity, marine aquatic eco-toxicity, terrestrial eco-toxicity, and photochemical oxidation. However, better effluent quality in this phase reduced the eutrophication load on environment.

Individualized In-Service Teacher Education. (Project IN-STEP). Evaluation Report, Phase II.

Science.gov (United States)

Thurber, John C.

Phase 2 of Project IN-STEP was conducted to revise, refine, and conduct further field testing of a new inservice teacher education model. The method developed (in Phase 1--see ED 003 905 for report) is an individualized, multi-media approach. Revision activities, based on feedback provided for Phase 1, include the remaking of six videotape…

Review of Development Survey of Phase Change Material Models in Building Applications

Directory of Open Access Journals (Sweden)

Hussein J. Akeiber

2014-01-01

Full Text Available The application of phase change materials (PCMs in green buildings has been increasing rapidly. PCM applications in green buildings include several development models. This paper briefly surveys the recent research and development activities of PCM technology in building applications. Firstly, a basic description of phase change and their principles is provided; the classification and applications of PCMs are also included. Secondly, PCM models in buildings are reviewed and discussed according to the wall, roof, floor, and cooling systems. Finally, conclusions are presented based on the collected data.

Design and Development of a Portable Metal Chip Baler using A System Design Approach

Directory of Open Access Journals (Sweden)

Hassan Mohd Fahrul

2017-01-01

Full Text Available A large amount of metal chips at workplace will result in untidy and unsafe condition thus measurements of safety are needed in some industries, where the metal chips will be collected and put into a container until the volume is sufficient to be recycled. Due to that reason, the metal chips require a lot of spaces for storage before going to recycle. In this study, a portable metal chip baler as a device for compacting those metal chips is presented based on a system approach of engineering design. Basically, the system design evolves through four phases of development that are started from conceptual design, preliminary system design, detail design and development to system test and evaluation. The portable metal chip baler uses current technology such as pneumatic cylinder to compress the metal chips so that the system capable to operate efficiently. The output from this system is the metal chips are compacted into a block shape and a working prototype was developed to prove the concept of the system. As a summary, the conceptual design of portable metal chip baler was proven and was presented using the philosophy of the systems design approach. This tool may assists workers especially in the Small-Medium Enterprise (SME manufacturing industries, school or universities’ workshops for managing metal chips easily and systematically.

An approach for the development of visual configuration systems

DEFF Research Database (Denmark)

Hvam, Lars; Ladeby, Klaes Rohde

2007-01-01

How can a visual configuration system be developed to support the specification process' in companies that manufacture customer tailored products? This article focuses on how visual configuration systems can be developed. The approach for developing visual configuration systems has been developed...... by Centre for Product Modelling (CPM) at The Technical University of Denmark. The approach is based on experiences from a visualization project in co-operation between CPM and the global provider of power protection American Power Conversion (APC). The visual configuration system was developed in 2001...... of the product in the visual configuration system....

Development of a Reliability Program approach to assuring operational nuclear safety

International Nuclear Information System (INIS)

Mueller, C.J.; Bezella, W.A.

1985-01-01

A Reliability Program (RP) model based on proven reliability techniques used in other high technology industries is being formulated for potential application in the nuclear power industry. Research findings are discussed. The reliability methods employed under NASA and military direction, commercial airline and related FAA programs were surveyed with several reliability concepts (e.g., quantitative reliability goals, reliability centered maintenance) appearing to be directly transferable. Other tasks in the RP development effort involved the benchmarking and evaluation of the existing nuclear regulations and practices relevant to safety/reliability integration. A review of current risk-dominant issues was also conducted using results from existing probabilistic risk assessment studies. The ongoing RP development tasks have concentrated on defining a RP for the operating phase of a nuclear plant's lifecycle. The RP approach incorporates safety systems risk/reliability analysis and performance monitoring activities with dedicated tasks that integrate these activities with operating, surveillance, and maintenance of the plant. The detection, root-cause evaluation and before-the-fact correction of incipient or actual systems failures as a mechanism for maintaining plant safety is a major objective of the RP

Advanced fabrication method for the preparation of MOF thin films: Liquid-phase epitaxy approach meets spin coating method.

KAUST Repository

Chernikova, Valeriya; Shekhah, Osama; Eddaoudi, Mohamed

2016-01-01

Here we report a new and advanced method for the fabrication of highly oriented/polycrystalline metal-organic framework (MOF) thin films. Building on the attractive features of the liquid-phase epitaxy (LPE) approach, a facile spin coating method

The role of technology in reducing health care costs. Phase II and phase III.

Energy Technology Data Exchange (ETDEWEB)

Cilke, John F.; Parks, Raymond C.; Funkhouser, Donald Ray; Tebo, Michael A.; Murphy, Martin D.; Hightower, Marion Michael; Gallagher, Linda K.; Craft, Richard Layne, II; Garcia, Rudy John

2004-04-01

In Phase I of this project, reported in SAND97-1922, Sandia National Laboratories applied a systems approach to identifying innovative biomedical technologies with the potential to reduce U.S. health care delivery costs while maintaining care quality. The effort provided roadmaps for the development and integration of technology to meet perceived care delivery requirements and an economic analysis model for development of care pathway costs for two conditions: coronary artery disease (CAD) and benign prostatic hypertrophy (BPH). Phases II and III of this project, which are presented in this report, were directed at detailing the parameters of telemedicine that influence care delivery costs and quality. These results were used to identify and field test the communication, interoperability, and security capabilities needed for cost-effective, secure, and reliable health care via telemedicine.

An integrative approach to the design methodology for 3-phase power conditioners in Photovoltaic Grid-Connected systems

International Nuclear Information System (INIS)

Rey-Boué, Alexis B.; García-Valverde, Rafael; Ruz-Vila, Francisco de A.; Torrelo-Ponce, José M.

2012-01-01

Highlights: ► A design methodology for Photovoltaic grid-connected systems is presented. ► Models of the Photovoltaic Generator and the 3-phase Inverter are described. ► The power factor and the power quality are regulated with vector control. ► Simulation and experimental results validate the design methodology. ► The proposed methodology can be extended to any Renewable or Industrial System. - Abstract: A novel methodology is presented in this paper, for the design of the Power and Control Subsystems of a 3-phase Photovoltaic Grid-Connected system in an easy and comprehensive way, as an integrative approach. At the DC side of the Power Subsystem, the Photovoltaic Generator modeling is revised and a simple model is proposed, whereas at the AC side, a vector analysis is done to deal with the instantaneous 3-phase variables of the grid-connected Voltage Source Inverter. A d–q control approach is established in the Control Subsystem, along with its specific tuned parameters, as a vector control alternative which will allow the decoupled control of the instantaneous active and reactive powers. A particular Case of Study is presented to illustrate the behavior of the design methodology regarding the fulfillment of the Photovoltaic plant specifications. Some simulations are run to study the performance of the Photovoltaic Generator together with the exerted d–q control to the grid-connected 3-phase inverter, and some experimental results, obtained from a built flexible platform, are also shown. The simulations and the experimental results validate the overall performance of the 3-phase Photovoltaic Grid-Connected system due to the attained unitary power factor operation together with good power quality. The final validation of the proposed design methodology is also achieved.

Protection of Lithium (Li) Anodes Using Dual Phase Electrolytes

Energy Technology Data Exchange (ETDEWEB)

Mikhaylik, Yuriy [Sion Power Corporation, Tucson, AZ (United States)

2014-09-30

Sion Power focused on metallic lithium anode protection, employing the Dual-Phase Electrolyte approach. The objective of this project was to develop a unique electrolyte providing two liquid phases having good Li+ conductivity, self-partitioning and immiscibility, serving separately the cathode and anode electrodes. This Dual-Phase Electrolyte was combined with thin film multi-layer, physical barrier membranes developed partially under a separate ARPA-E funded project. All these protective structures were stabilized by externally applied pressure. This strategy was used for Li-S cells. The development directly addressed cell safety, particularly higher thermal stability, while also allowing higher energies and cycle life. Safety tests showed that 100% of cells with Dual-Phase Electrolyte were intact and did not exhibit thermal runaway up to 178 °C and thus met the project objective of increasing the runaway temperature to >165°C. Cells also passed cycling at USABC Dynamic Stress Test conditions developed for Electric Vehicle applications and generated specific energy > 300 Wh/kg.

Student Development in Higher Education: A Constructivist Approach

Science.gov (United States)

Ibrahim, Rania; Sarirete, Akila

Sustainable education requires a new approach to knowledge acquisition and learning. This approach is manifested in merging student experience inside and outside the classroom, which eventually results in shaping the 21 st century lifelong learner. This paper presents an innovative student development model based on the constructivist approach; showing the collaboration between student affairs and academics. Furthermore, it illustrates a unique experience implemented at Effat University for developing the student as a whole person. This is done to complement the student's academic experience with the necessary skills and abilities derived from Effat University mission that focuses on creating women leaders. The student finds herself in a journey of self development and growth throughout the course of her study until graduation. At the time of graduation, she is equipped with all what it takes to be a successful career woman and a leader of change in her society.

Phase transition and frustration in nuclear physics and astrophysics

International Nuclear Information System (INIS)

Hasnaoui, K.

2008-10-01

The thermodynamics of nuclear matter which constitutes the crust of proto-neutron stars and neutron stars is studied in this thesis. Obtaining information on the star matter thermodynamics will enhance the understanding of physical phenomena involved in the cooling of proto-neutron stars, and in the formation of type II supernovae. One of the main goals is to extract the star-matter phase diagram in order to determine if instabilities and/or critical points are present. The work is divided into two parts: in the first one classical approaches are developed, while the second one presents a quantum approach. The classical approaches are based on the Ising model and on the renormalisation group. They give us qualitative information on the phenomenology of phase transitions for star matter, and allow a discussion on the properties of the phase diagram under the generic phenomenon of Coulomb frustration. The quantum approach is based on a fermionic molecular dynamics model that we have developed from the density functional formalism, and numerically implemented using Skyrme forces optimized on neutron rich nuclei and neutron matter. This thesis work shows some first applications to the study the thermodynamics of finite nuclear systems, as well as nuclear structure calculations for light nuclei. A new formalism based on the molecular dynamics model is sketched which will ultimately allow treating the numerical quantum problem for the infinite star matter. (author)

Malaria Vaccine Development: The Need for Novel Approach-es: A Review Article

Directory of Open Access Journals (Sweden)

Shima MAHMOUDI

2018-03-01

Full Text Available Background: Although rigorous efforts have substantially decreased the malaria burden through decades, it still threatens the lives of millions of children. Development of an effective vaccine can provide important approach in malaria control strategies. Unfortunately, development of an effective vaccine for falciparum malaria has been hindered by the extreme complexity of malaria parasite biology, complex and diverse parasite genomes, and immune evasion by the parasites as well as the intricate nature of the parasites infection cycle. The aim of this review was to discuss the different approaches to malaria vaccine development until now.Methods: Scientific databases, including MEDLINE (via PubMed and SCOPUS were searched up to 30 Jan 2017 and the articles regarding malaria vaccine development were taken into examination.Results: Several strategies for malaria vaccine development including pre-erythrocytic vaccines, antibody-based subunit vaccines, vectored vaccines, whole sporozoite vaccines, genetically Attenuated parasites and sporozoite subunit vaccine, erythrocytic vaccines, sexual stage vaccine, transmission-blocking vaccine as well as synthetic peptides and conjugate vaccine has been introduced. However, the success has been limited thus far.Conclusion: Although development of malaria vaccine over the past 70 year has been continued, the discovery, development, and licensing of a malaria vaccine formulation, which meets safety, affordability, accessibility, applicability, and efficacy has not yet been achieved.

Development of generalized boiling transition model applicable for wide variety of fuel bundle geometries. Basic strategy and numerical approaches

International Nuclear Information System (INIS)

Ninokata, Hisashi; Sadatomi, Michio; Okawa, Tomio

2003-01-01

In order to establish a key technology to realize advanced BWR fuel designs, a three-year project of the advanced subchannel analysis code development had been started since 2002. The five dominant factors involved in the boiling transitional process in the fuel bundles were focused. They are, (1) inter-subchannel exchanges, (2) influences of obstacles (3) dryout of liquid film, (4) transition of two-phase flow regimes and (5) deposition of droplets. It has been recognized that present physical models or constitutive equations in subchannel formulations need to be improved so that they include geometrical effects in the fuel bundle design more mechanistically and universally. Through reviewing literatures and existent experimental results, underlying elementary processes and geometrical factors that are indispensable for improving subchannel codes were identified. The basic strategy that combines numerical and experimental approaches was proposed aiming at establishment of mechanistic models for the five dominant factors. In this paper, the present status of methodologies for detailed two-phase flow studies has been summarized. According to spatial scales of focused elementary processes, proper numerical approaches were selected. For some promising numerical approaches, preliminary calcitonins were performed for assessing their applicability to investigation of elementary processes involved in the boiling transition. (author)

HERCA-WENRA Approach for a better cross-border coordination of protective actions during the early phase of a nuclear accident

International Nuclear Information System (INIS)

Bijlholt, Jette; Constantinou, Costas; Janssens, Augustin; ); Djounova, Jana; Fueloep, Nandor; Gering, Florian; Lieser, Joachim; Halldorsson, Oskar; Haywood, Stephanie; Hofer, Peter; Isnard, Olivier; Kuhlen, Johannes; Rother, Wolfram; Majerus, Patrick; Murith, Christophe; Nizamska, Marina; Rauber, Dominique; Rusch, Ronald; Stahl, Thorsten; Stephen, Patrick; Tkavc, Marjan; Van Gelder, Iris; Degueldre, Didier; Vandecasteele, Christian; Fuchsova, Dagmar; Genthon, Benedicte; Jamet, Philippe; Gilli, Ludivine; Lachaume, Jean-Luc; Perrin, Marie-Line; Xicluna, Delphine; Goerts, Peter; Greipl, Christian; Kuhlen, Johannes; Gurgui, Antoni; Mozas, Alfredo; Calvaro, Jose-Manuel Martin; Hohl, Harry; Rauber, Dominique; Hubbard, Lynn; Lindh, Karin; Majerus, Patrick; McMahon, Ciara; Metke, Eduard; Sokolikova, Adriana; Piller, Georges; Reiman, Lasse; Aaltonen, Hannele; Kuusi, Antero; Senior, David; Temple, Charles; Ugletveit, Finn; Holo, Eldri; Vandecasteele, Christian; Guzman, Olvido; Mueller-Ecker, Dieter

2014-01-01

The HERCA-WENRA Approach is an incentive approach that comprises the necessary mechanisms for countries to exchange adequate information and to achieve practical and operational solutions on a voluntary basis during an emergency leading to a uniform way of dealing with any serious radiological emergency situation, regardless of national border line, hence allowing for coherent and coordinated protective actions. The HERCA-WENRA Approach has the potential to improve the coherence of the response in case of a nuclear accident with impact on territories of other countries and to be used as guidance to implement Article 99.11 and 99.22 of the Euratom-BSS. It also fulfils recommendation No. 12.7.b of the so-known ENCO study and it further addresses some of the other recommendations. Content: General presentation of the HERCA WENRA Approach for a better cross-border coordination of protective actions during the early phase of a nuclear accident. Part I - HERCA-WENRA Approach for a better cross-border coordination of protective actions during the early phase of a nuclear accident. - General Mechanism. Part II - HERCA-WENRA Approach in case of a Severe Accident requiring Rapid Decisions for Protective Actions, while very little is known about the Situation

Developing regulatory approaches

International Nuclear Information System (INIS)

Axelsson, Lars

2012-01-01

Lars Axelsson presented SSM progress on oversight of LMfS/SC since the Chester 1 Workshop in 2007. Current SSM approaches for safety culture oversight include targeted safety management and safety culture inspections, compliance inspections which cover aspects of safety management/safety culture and multi-disciplinary team inspections. Examples of themes for targeted inspections include management of ambiguous operational situations or other weak signals, understanding of and attitudes to Human Performance tools, the Safety Department's role and authority and Leadership for safety. All regulatory activities provide inputs for the SSM yearly safety evaluation of each licensee. A form has been developed to capture safety culture observations from inspections and other interactions with licensees. Analysis will be performed to identify patterns and provide information to support planning of specific Safety Culture activities. Training has been developed for regulatory staff to enhance the quality of regulatory interventions on safety culture. This includes a half-day seminar to provide an overview of safety culture, and a workshop which provides more in-depth discussion on cultural issues and how to capture those during regulatory activities. Future plans include guidance for inspectors, and informal seminars on safety culture with licensees

Membrane/distillation hybrid process research and development. Final report, phase II

Energy Technology Data Exchange (ETDEWEB)

Mazanec, T.J.

1997-07-01

This report covers work conducted under the grant awarded to BP by DOE in late 1991 entitled {open_quotes}Membrane/Distillation Hybrid Process Research and Development.{close_quotes} The program was directed towards development and commercialization of the BP process for separation of vapor phase olefins from non-olefins via facilitated transport using an aqueous facilitator. The program has come to a very successful conclusion, with formation of a partnership between BP and Stone and Webster Engineering Corporation (SWEC) to market and commercialize the technology. The focus of this report is the final portion of the program, during which engineering re-design, facilitator optimization, economic analysis, and marketing have been the primary activities. At the end of Phase II BP was looking to partner with an engineering firm to advance the selective olefin recovery (SOR) technology from the lab/demo stage to full commercialization. In August 1995 BP and SWEC reached an agreement to advance the technology by completing additional Phase III work with DOE and beginning marketing activities.

SAFT-assisted sound beam focusing using phased arrays (PA-SAFT) for non-destructive evaluation

Science.gov (United States)

Nanekar, Paritosh; Kumar, Anish; Jayakumar, T.

2015-04-01

Focusing of sound has always been a subject of interest in ultrasonic non-destructive evaluation. An integrated approach to sound beam focusing using phased array and synthetic aperture focusing technique (PA-SAFT) has been developed in the authors' laboratory. The approach involves SAFT processing on ultrasonic B-scan image collected by a linear array transducer using a divergent sound beam. The objective is to achieve sound beam focusing using fewer elements than the ones required using conventional phased array. The effectiveness of the approach is demonstrated on aluminium blocks with artificial flaws and steel plate samples with embedded volumetric weld flaws, such as slag and clustered porosities. The results obtained by the PA-SAFT approach are found to be comparable to those obtained by conventional phased array and full matrix capture - total focusing method approaches.

Phase-unwrapping algorithm by a rounding-least-squares approach

Science.gov (United States)

Juarez-Salazar, Rigoberto; Robledo-Sanchez, Carlos; Guerrero-Sanchez, Fermin

2014-02-01

A simple and efficient phase-unwrapping algorithm based on a rounding procedure and a global least-squares minimization is proposed. Instead of processing the gradient of the wrapped phase, this algorithm operates over the gradient of the phase jumps by a robust and noniterative scheme. Thus, the residue-spreading and over-smoothing effects are reduced. The algorithm's performance is compared with four well-known phase-unwrapping methods: minimum cost network flow (MCNF), fast Fourier transform (FFT), quality-guided, and branch-cut. A computer simulation and experimental results show that the proposed algorithm reaches a high-accuracy level than the MCNF method by a low-computing time similar to the FFT phase-unwrapping method. Moreover, since the proposed algorithm is simple, fast, and user-free, it could be used in metrological interferometric and fringe-projection automatic real-time applications.

General approach to standardization of the solid-phase radioimmunoassay for quantitation of class-specific antibodies

Energy Technology Data Exchange (ETDEWEB)

Zollinger, W D; Boslego, J W [Walter Reed Army Inst. of Research, Washington, DC (USA)

1981-10-30

The feasibility of using an anti-human immunoglobulin/human immunoglobulin/(/sup 125/I)anti-human immunoglobulin 'sandwich' in a solid-phase radioimmunoassay to produce a standard curve which could be used to quantitate antigen-specific antibody of a particular immunoglobulin class was investigated. The amount of secondary antibody (SAb) bound was determined as a function of whether the primary antibody (PAb) was bound to its specific solid-phase antigen or by a solid-phase anti-human immunoglobulin. No significant difference between the two values was observed. Quantitation of anti-tetanus toxoid antibody by this method was in a good agreement with quantitative precipitin tests. Comparison of SAb binding as a function of the way the PAb is bound was extended to class-specific PAb by use of murine monoclonal antibodies to meningococcal antigens. In most cases somewhat greater binding of SAb occurred when PAb was bound to antigen, but in several cases where low avidity antibody and/or poor quality antigens were used, greater SAb binding occurred when PAb was bound by anti-mouse immunoglobulin. The results indicate that this approach may be useful as a general method for standardizing the SPRIA and other solid-phase immunoassays such as the ELISA to measure class-specific antibody.

Ada developers' supplement to the recommended approach

Science.gov (United States)

Kester, Rush; Landis, Linda

1993-01-01

This document is a collection of guidelines for programmers and managers who are responsible for the development of flight dynamics applications in Ada. It is intended to be used in conjunction with the Recommended Approach to Software Development (SEL-81-305), which describes the software development life cycle, its products, reviews, methods, tools, and measures. The Ada Developers' Supplement provides additional detail on such topics as reuse, object-oriented analysis, and object-oriented design.

Education positive approach: contributions to human development

Directory of Open Access Journals (Sweden)

Clara ROMERO PÉREZ

2012-02-01

Full Text Available This article analizes the current theoretical perspectives underlying educational proposals aimed at promoting the positive development of the people. Firstly we show the most important characteristics of the positive approach. Then, we focus on the positive concept of the inner and its relation to eudaimonia, self-care and emotional selfgovernance. Thirdly, with reference to the contributions of Positive Psychology and Prevention Science we examine the two points of view –hedonic and eudaemonic– from which different pedagogical approaches are based and focus towards education for the welfare, social-emotional development and educational character. We conclude that, despite the lack of practical knowledge about happiness and the art of living, a positive education oriented to the human construction processes must promote both emotional and social skills such as feelings and moral responsibilities for the optimal development of human being.

Autonomous Aerobraking Development Software: Phase 2 Summary

Science.gov (United States)

Cianciolo, Alicia D.; Maddock, Robert W.; Prince, Jill L.; Bowes, Angela; Powell, Richard W.; White, Joseph P.; Tolson, Robert; O'Shaughnessy, Daniel; Carrelli, David

2013-01-01

NASA has used aerobraking at Mars and Venus to reduce the fuel required to deliver a spacecraft into a desired orbit compared to an all-propulsive solution. Although aerobraking reduces the propellant, it does so at the expense of mission duration, large staff, and DSN coverage. These factors make aerobraking a significant cost element in the mission design. By moving on-board the current ground-based tasks of ephemeris determination, atmospheric density estimation, and maneuver sizing and execution, a flight project would realize significant cost savings. The NASA Engineering and Safety Center (NESC) sponsored Phase 1 and 2 of the Autonomous Aerobraking Development Software (AADS) study, which demonstrated the initial feasibility of moving these current ground-based functions to the spacecraft. This paper highlights key state-of-the-art advancements made in the Phase 2 effort to verify that the AADS algorithms are accurate, robust and ready to be considered for application on future missions that utilize aerobraking. The advancements discussed herein include both model updates and simulation and benchmark testing. Rigorous testing using observed flight atmospheres, operational environments and statistical analysis characterized the AADS operability in a perturbed environment.

Software Development using Object-First Approach: a New Learning Strategy

Directory of Open Access Journals (Sweden)

Gurdeep S Hura

2017-08-01

Full Text Available Software Engineering approach deals with the Software Development (SD that is aligned with design and development of software applications. The Software Development may be implemented in a variety of techniques but its implementation using a procedural paradigm and an imperative language seem to be more effective and efficient for the design and implementation of software applications. The procedural approach for Software Development offers advantages as this it may be used to teach some basic features of programming languages. The object of this paper is to introduce the software development and associated object-first approach for the design of software project application using top-down method. This approach defines functions and modules as basic units for the design and implementation and also for offering hands-on experiences with the basics of programming languages of sequences, selections, iterations structures. These structures will be used to define various modules with programming language constructs for of software development process. The software Development process is one of the very crucial processes of software engineering.

Development of Latent Heat Storage Phase Change Material Containing Plaster

Directory of Open Access Journals (Sweden)

Diana BAJARE

2016-05-01

Full Text Available This paper reviews the development of latent heat storage Phase Change Material (PCM containing plaster as in passive application. Due to the phase change, these materials can store higher amounts of thermal energy than traditional building materials and can be used to add thermal inertia to lightweight constructions. It was shown that the use of PCMs have advantages stabilizing the room temperature variations during summer days, provided sufficient night ventilation is allowed. Another advantage of PCM usage is stabilized indoor temperature on the heating season. The goal of this study is to develop cement and lime based plaster containing microencapsulated PCM. The plaster is expected to be used for passive indoor applications and enhance the thermal properties of building envelope. The plaster was investigated under Scanning Electron Microscope and the mechanical, physical and thermal properties of created plaster samples were determined.

Multiphase, multicomponent phase behavior prediction

Science.gov (United States)

Dadmohammadi, Younas

Accurate prediction of phase behavior of fluid mixtures in the chemical industry is essential for designing and operating a multitude of processes. Reliable generalized predictions of phase equilibrium properties, such as pressure, temperature, and phase compositions offer an attractive alternative to costly and time consuming experimental measurements. The main purpose of this work was to assess the efficacy of recently generalized activity coefficient models based on binary experimental data to (a) predict binary and ternary vapor-liquid equilibrium systems, and (b) characterize liquid-liquid equilibrium systems. These studies were completed using a diverse binary VLE database consisting of 916 binary and 86 ternary systems involving 140 compounds belonging to 31 chemical classes. Specifically the following tasks were undertaken: First, a comprehensive assessment of the two common approaches (gamma-phi (gamma-ϕ) and phi-phi (ϕ-ϕ)) used for determining the phase behavior of vapor-liquid equilibrium systems is presented. Both the representation and predictive capabilities of these two approaches were examined, as delineated form internal and external consistency tests of 916 binary systems. For the purpose, the universal quasi-chemical (UNIQUAC) model and the Peng-Robinson (PR) equation of state (EOS) were used in this assessment. Second, the efficacy of recently developed generalized UNIQUAC and the nonrandom two-liquid (NRTL) for predicting multicomponent VLE systems were investigated. Third, the abilities of recently modified NRTL model (mNRTL2 and mNRTL1) to characterize liquid-liquid equilibria (LLE) phase conditions and attributes, including phase stability, miscibility, and consolute point coordinates, were assessed. The results of this work indicate that the ϕ-ϕ approach represents the binary VLE systems considered within three times the error of the gamma-ϕ approach. A similar trend was observed for the for the generalized model predictions using

Connected Vehicle Pilot Deployment Program phase 1 : comprehensive deployment plan : New York City : volume 1 : technical application : part I : technical and management approach.

Science.gov (United States)

2016-08-01

This document describes the Deployment Plan for the New York City Department of Transportation (NYC) Connected Vehicle Pilot Deployment (CVPD) Project. This plan describes the approach to complete Phase 2 Design/Build/Test, and Phase 3 Operate and Ma...

VTAE Equity Staff Development Workshops and Services--Phase II. Final Report.

Science.gov (United States)

Baldus, Lorayne; Nelson, Orville

The Phase II Equity Staff Development project was revised in response to a need to develop an equity strategic planning model with a vision statement, goals, and objectives. The Equity Strategic Planning Model was presented to administrators of Wisconsin Vocational, Technical, and Adult Education (VTAE) colleges for their use in district strategic…

Using a Community-Engaged Research (CEnR) approach to develop and pilot a photo grid method to gain insights into early child health and development in a socio-economic disadvantaged community.

Science.gov (United States)

Lowrie, Emma; Tyrrell-Smith, Rachel

2017-01-01

This paper reports on the use of a Community-Engaged Research (CEnR) approach to develop a new research tool to involve members of the community in thinking about priorities for early child health and development in a deprived area of the UK. The CEnR approach involves researchers, professionals and members of the public working together during all stages of research and development.Researchers used a phased approach to the development of a Photo Grid tool including reviewing tools which could be used for community engagement, and testing the new tool based on feedback from workshops with local early years professionals and parents of young children.The Photo Grid tool is a flat square grid on which photo cards can be placed. Participants were asked to pace at the top of the grid the photos they considered most important for early child health and development, working down to the less important ones at the bottom. The findings showed that the resulting Photo Grid tool was a useful and successful method of engaging with the local community. The evidence for this is the high numbers of participants who completed a pilot study and who provided feedback on the method. By involving community members throughout the research process, it was possible to develop a method that would be acceptable to the local population, thus decreasing the likelihood of a lack of engagement. The success of the tool is therefore particularly encouraging as it engages "seldom heard voices," such as those with low literacy. The aim of this research was to consult with professionals and parents to develop a new research toolkit (Photo Grid), to understand community assets and priorities in relation to early child health and development in Blackpool, a socio-economic disadvantaged community. A Community-Engaged Research (CEnR) approach was used to consult with community members. This paper describes the process of using a CEnR approach in developing a Photo Grid toolkit. A phased CEnR approach

Development and implementation of UT procedures for nuclear and other applications using TRL phased array probes

International Nuclear Information System (INIS)

Chardome, V.; Delaide, M.; Cermak, J.; Cruysweegs, E.; Plateau, M.

2006-01-01

In the past, Vincotte developed, qualified and applied various UT procedures for the automated in-service inspection of austenitic and dissimilar metal welds, using conventional ultrasonic probes. In a process of continuous improvement, Vincotte is upgrading these existing procedures by applying low frequency TRL phased array probes. This presentation situates this recent innovation within the phased array history of Vincotte. Particular attention will be paid to these newest phased array developments, in terms of probe development, angled beam generation and scanning patterns. (orig.)

A Real Time AI Approach to Discrimination Boost Phase Optical Sensor Systems in SDI Architectures

Science.gov (United States)

Sloggett, David R.

1990-04-01

Interest has been rekindled in the potential utility of Ballistic Missile Defence (BMD) systems 1,2 and their ability to enhance the existing NATO strategic defence posture 3,4. Whereas in the past BMD systems have been thought to be vulnerable to relatively simple offence countermeasures, technological developments that have occurred over the past 20 years offer the potential to solve some of the main criticisms that have bedeviled BMD research since its inception in the early 1950s. One of the key areas where dramatic developments have taken place is in the field of electro-optic sensor technologies where developments in device sensitivity and packing density offer new solutions to threat detection, tracking and discrimination that complement data traditionally associated with radar based systems. Analysis has shown 5 that optical sensor systems can make a significant contribution to threat analysis in the boost and mid course phases of flight of ballistic missile systems. In the Boost phase the large amounts of energy contained within the plume of a ballistic missile system provides a signature that must be detected against cloud and earth backgrounds - necessitating viewing from space. The process of detection is complicated by reflected sunlight and other sources of false alarms. The optical sensor systems must therefore be adaptable and capable of reasoning about the location of the signatures, their persistence and temporal variations. Much of this processing is ideally carried out at the sensor system - in order to eliminate false alarms and reduce the communications bandwidths required to transfer the sensor data to centralised early warning and battle management facilities. In the mid course phase optical sensor systems can be used to detect warm objects against the background of deep space. These sensor systems can form tracks on these objects that can be merged into 3D tracks as data from individual sensor systems are combined. As closely spaced objects

Development of a generalized correlation for phase-velocity measurements obtained from impedance-probe pairs in two-phase flow systems

International Nuclear Information System (INIS)

Hsu, C.T.; Keshock, E.G.; McGill, R.N.

1983-01-01

A flag type electrical impedance probe has been developed at the Oak Ridge National Lab (ORNL) to measure liquid- and vapor-phase velocities in steam-water mixtures flowing through rod bundles. Measurements are made by utilizing the probes in pairs, installed in line, parallel to the flow direction, and extending out into the flow channel. The present study addresses performance difficulties by examining from a fundamental point of view the two-phase flow system which the impedance probes typically operate in. Specifically, the governing equations (continuity, momentum, energy) were formulated for both air-water and steam-water systems, and then subjected to a scaling analysis. The scaling analysis yielded the appropriate dimensionless parameters of significance in both kinds of systems. Additionally, with the aid of experimental data obtained at ORNL, those parameters of significant magnitude were established. As a result, a generalized correlation was developed for liquid and vapor phase velocities that makes it possible to employ the impedance probe velocity measurement technique in a wide variety of test configurations and fluid combinations

Designing a Model for Trauma System Management Using Public Health Approach: The Case of Iran

Directory of Open Access Journals (Sweden)

Farzad Panahi

2012-01-01

Full Text Available Trauma is a leading cause of death and disability around the world. Injuries are responsible for about six million deaths annually, of which ninety percent occur in developing countries. In Iran, injuries are the most common cause of death among age groups below fifty. Trauma system development is a systematic and comprehensive approach to injury prevention and treatment whose effectiveness has been proved. The present study aims at designing a trauma system management model as the first step toward trauma system establishment in Iran. In this qualitative research, a conceptual framework was developed based on the public health approach and three well-known trauma system models. We used Benchmarks, Indicators and Scoring (BIS to analyze the current situation of Iran trauma care system. Then the trauma system management was designed using the policy development phase of public health approach The trauma system management model, validated by a panel of experts, describes lead agency, trauma system plan, policy-making councils, and data-based control according to the four main functions of management: leading, planning, organizing and controlling. This model may be implemented in two phases: the exclusive phase, focusing on resource integration and the inclusive phase, which concentrates on system development. The model could facilitate the development of trauma system in Iran through pilot studies as the assurance phase of public health approach. Furthermore, the model can provide a practical framework for trauma system management at the international level.

Mechanisms of diffusional phase transformations in metals and alloys

CERN Document Server

Aaronson, Hubert I; Lee, Jong K

2010-01-01

Developed by the late metallurgy professor and master experimentalist Hubert I. Aaronson, this collection of lecture notes details the fundamental principles of phase transformations in metals and alloys upon which steel and other metals industries are based. Mechanisms of Diffusional Phase Transformations in Metals and Alloys is devoted to solid-solid phase transformations in which elementary atomic processes are diffusional jumps, and these processes occur in a series of so-called nucleation and growth through interface migration. Instead of relying strictly on a pedagogical approach, it doc

Recent Developments in Solid-Phase Extraction for Near and Attenuated Total Reflection Infrared Spectroscopic Analysis

Directory of Open Access Journals (Sweden)

Christian W. Huck

2016-05-01

Full Text Available A review with more than 100 references on the principles and recent developments in the solid-phase extraction (SPE prior and for in situ near and attenuated total reflection (ATR infrared spectroscopic analysis is presented. New materials, chromatographic modalities, experimental setups and configurations are described. Their advantages for fast sample preparation for distinct classes of compounds containing different functional groups in order to enhance selectivity and sensitivity are discussed and compared. This is the first review highlighting both the fundamentals of SPE, near and ATR spectroscopy with a view to real sample applicability and routine analysis. Most of real sample analyses examples are found in environmental research, followed by food- and bioanalysis. In this contribution a comprehensive overview of the most potent SPE-NIR and SPE-ATR approaches is summarized and provided.

Biotechnology approaches to developing herbicide tolerance ...

African Journals Online (AJOL)

The use of herbicides has revolutionized weed control in many crop production systems. However, with the increasing development of weed resistances to many popular selective herbicides, the need has arisen to rethink the application of chemical weed control. Approaches to maintain the efficiency of chemical weed ...

An approach towards sustainable groundwater development

African Journals Online (AJOL)

To address water availability problems in a semi-arid country like South Africa, the National Water Act (RSA, 1998) proposes that specialists adopt an approach that is strategic, deliberate and dictated by socio-political reforms and socioeconomic development needs on a programmatic basis for long-term sustainability.

China's Approach to International Development: A Study of Southeast Asia

Directory of Open Access Journals (Sweden)

Neil Renwick

2015-12-01

Full Text Available China is establishing itself as a new international aid donor. This study explains China's emerging approach to international development assistance. The paper addresses the question of how far China's understanding of "development" is an appropriate basis for genuinely "win-win" relationships? The paper explores this question by examining China's relationship with Southeast Asia. China is re-emphasising its commitment and partnership credentials with neighbouring states, some of whom have many people living in poverty and as countries are in need of development assistance. The paper identifies key facets of China's approach to international development, examines economic, political and strategic factors underpinning China's approach in Southeast Asia. Adopting a Human Security perspective, it assesses China's development contribution with reference to Cambodia, Laos and Myanmar and highlights popular opposition. The study finds that Chinese trade and investment are making a significant contribution to the region's economic growth. However, the analysis identifies two problems in China's approach, an over-reliance on the level of state-to-state relations and too narrow a domain of engagement centred upon economic cooperation. China needs to incorporate a societal engagement strategy highlighting transparency and accountability of Chinese corporate behaviour. It also needs to re-balance its approach by emphasising human capital capability and capacity-building across the non-economic social and cultural domains. China's approach to international development is a rapid learning process and is emerging, but still has further to go.

A Preisach approach to modeling partial phase transitions in the first order magnetocaloric material MnFe(P,As)

Energy Technology Data Exchange (ETDEWEB)

Moos, L. von, E-mail: lmoo@dtu.dk [Department of Energy Conversion and Storage, Technical University of Denmark, 4000 Roskilde (Denmark); Bahl, C.R.H.; Nielsen, K.K.; Engelbrecht, K. [Department of Energy Conversion and Storage, Technical University of Denmark, 4000 Roskilde (Denmark); Küpferling, M.; Basso, V. [Istituto Nazionale di Ricerca Metrologica, 10135 Torino (Italy)

2014-02-15

Magnetic refrigeration is an emerging technology that could provide energy efficient and environmentally friendly cooling. Magnetocaloric materials in which a structural phase transition is found concurrently with the magnetic phase transition are often termed first order magnetocaloric materials. Such materials are potential candidates for application in magnetic refrigeration devices. However, the first order materials often have adverse properties such as hysteresis, making actual performance troublesome to quantify, a subject not thoroughly studied within this field. Here we investigate the behavior of MnFe(P,As) under partial phase transitions, which is similar to what materials experience in actual magnetic refrigeration devices. Partial phase transition curves, in the absence of a magnetic field, are measured using calorimetry and the experimental results are compared to simulations of a Preisach-type model. We show that this approach is applicable and discuss what experimental data is required to obtain a satisfactory material model.

SU(2 and SU(1,1 Approaches to Phase Operators and Temporally Stable Phase States: Applications to Mutually Unbiased Bases and Discrete Fourier Transforms

Directory of Open Access Journals (Sweden)

Maurice R. Kibler

2010-07-01

Full Text Available We propose a group-theoretical approach to the generalized oscillator algebra Aκ recently investigated in J. Phys. A: Math. Theor. 2010, 43, 115303. The case κ ≥ 0 corresponds to the noncompact group SU(1,1 (as for the harmonic oscillator and the Pöschl-Teller systems while the case κ < 0 is described by the compact group SU(2 (as for the Morse system. We construct the phase operators and the corresponding temporally stable phase eigenstates for Aκ in this group-theoretical context. The SU(2 case is exploited for deriving families of mutually unbiased bases used in quantum information. Along this vein, we examine some characteristics of a quadratic discrete Fourier transform in connection with generalized quadratic Gauss sums and generalized Hadamard matrices.

A Finite-Volume approach for compressible single- and two-phase flows in flexible pipelines with fluid-structure interaction

Science.gov (United States)

Daude, F.; Galon, P.

2018-06-01

A Finite-Volume scheme for the numerical computations of compressible single- and two-phase flows in flexible pipelines is proposed based on an approximate Godunov-type approach. The spatial discretization is here obtained using the HLLC scheme. In addition, the numerical treatment of abrupt changes in area and network including several pipelines connected at junctions is also considered. The proposed approach is based on the integral form of the governing equations making it possible to tackle general equations of state. A coupled approach for the resolution of fluid-structure interaction of compressible fluid flowing in flexible pipes is considered. The structural problem is solved using Euler-Bernoulli beam finite elements. The present Finite-Volume method is applied to ideal gas and two-phase steam-water based on the Homogeneous Equilibrium Model (HEM) in conjunction with a tabulated equation of state in order to demonstrate its ability to tackle general equations of state. The extensive application of the scheme for both shock tube and other transient flow problems demonstrates its capability to resolve such problems accurately and robustly. Finally, the proposed 1-D fluid-structure interaction model appears to be computationally efficient.

Bridging Knowledge: A Collective Undergraduate Thesis Development Approach

Science.gov (United States)

Holdsworth, Jason K.; Arun, Özgür

2017-01-01

While there are various approaches to gerontological and geriatrics (and social sciences) education globally, a component commonly included in undergraduate education is a final thesis project. In Turkey, the Department of Gerontology at Akdeniz University has undertaken a unique approach to thesis development that values and draws on accessing…

A new approach for determining phase response curves reveals that Purkinje cells can act as perfect integrators.

Directory of Open Access Journals (Sweden)

Elena Phoka

2010-04-01

Full Text Available Cerebellar Purkinje cells display complex intrinsic dynamics. They fire spontaneously, exhibit bistability, and via mutual network interactions are involved in the generation of high frequency oscillations and travelling waves of activity. To probe the dynamical properties of Purkinje cells we measured their phase response curves (PRCs. PRCs quantify the change in spike phase caused by a stimulus as a function of its temporal position within the interspike interval, and are widely used to predict neuronal responses to more complex stimulus patterns. Significant variability in the interspike interval during spontaneous firing can lead to PRCs with a low signal-to-noise ratio, requiring averaging over thousands of trials. We show using electrophysiological experiments and simulations that the PRC calculated in the traditional way by sampling the interspike interval with brief current pulses is biased. We introduce a corrected approach for calculating PRCs which eliminates this bias. Using our new approach, we show that Purkinje cell PRCs change qualitatively depending on the firing frequency of the cell. At high firing rates, Purkinje cells exhibit single-peaked, or monophasic PRCs. Surprisingly, at low firing rates, Purkinje cell PRCs are largely independent of phase, resembling PRCs of ideal non-leaky integrate-and-fire neurons. These results indicate that Purkinje cells can act as perfect integrators at low firing rates, and that the integration mode of Purkinje cells depends on their firing rate.

Phase behaviour of symmetric binary mixtures with partially miscible components in slit-like pores. Application of the fundamental measure density functional approach

CERN Document Server

Martínez, A; Patrykiejew, A; Sokolowski, S

2003-01-01

We investigate adsorption in slit-like pores of model symmetric binary mixtures exhibiting demixing in bulk phase, by using a density functional approach. Our focus is on the evaluation of the first-order phase transitions in adsorbed fluids and the lines separating mixed and demixed phases. The scenario for phase transitions is sensitive to the pore width and to the energy of adsorption. Both these parameters can change the phase diagrams of the confined fluid. In particular, for relatively wide pores and for strong wall-fluid interactions, the demixing line can precede the first-order transition. Moreover, a competition between layering transitions and demixing within particular layers also leads to further enrichment of the phase diagram.

Theoretical Prediction of Melting Relations in the Deep Mantle: the Phase Diagram Approach

Science.gov (United States)

Belmonte, D.; Ottonello, G. A.; Vetuschi Zuccolini, M.; Attene, M.

2016-12-01

Despite the outstanding progress in computer technology and experimental facilities, understanding melting phase relations in the deep mantle is still an open challenge. In this work a novel computational scheme to predict melting relations at HP-HT by a combination of first principles DFT calculations, polymer chemistry and equilibrium thermodynamics is presented and discussed. The adopted theoretical framework is physically-consistent and allows to compute multi-component phase diagrams relevant to Earth's deep interior in a broad range of P-T conditions by a convex-hull algorithm for Gibbs free energy minimisation purposely developed for high-rank simplexes. The calculated phase diagrams are in turn used as a source of information to gain new insights on the P-T-X evolution of magmas in the deep mantle, providing some thermodynamic constraints to both present-day and early Earth melting processes. High-pressure melting curves of mantle silicates are also obtained as by-product of phase diagram calculation. Application of the above method to the MgO-Al2O3-SiO2 (MAS) ternary system highlights as pressure effects are not only able to change the nature of melting of some minerals (like olivine and pyroxene) from eutectic to peritectic (and vice versa), but also simplify melting relations by drastically reducing the number of phases with a primary phase field at HP-HT conditions. It turns out that mineral phases like Majorite-Pyrope garnet and Anhydrous Phase B (Mg14Si5O24), which are often disregarded in modelling melting processes of mantle assemblages, are stable phases at solidus or liquidus conditions in a P-T range compatible with the mantle transition zone (i.e. P = 16 - 23 GPa and T = 2200 - 2700 °C) when their thermodynamic and thermophysical properties are properly assessed. Financial support to the Senior Author (D.B.) during his stay as Invited Scientist at the Institut de Physique du Globe de Paris (IPGP, Paris) is warmly acknowledged.

Using the Grade Approach to Support the Development of Recommendations for Public Health Interventions in Radiation Emergencies

International Nuclear Information System (INIS)

Carr, Z.; Clarke, M.; Akl, E.A.; Schneider, R.; Murith, C.; Li, C.; Parrish-Sprowl, J.; Stenke, L.; Cui-Ping, L.; Bertrand, S.; Miller, C.

2016-01-01

The World Health Organization (WHO) guideline development policy requires that WHO guidelines be developed in a manner that is transparent and based on all available evidences, which must be synthesised and formally assessed for quality. To fulfil this requirement, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach of rating quality of evidence and grading strength of recommendations was applied when developing the WHO recommendations on public health interventions in radiation emergencies. The guideline development group (GDG) formulated 10 PICO (P: population; I: intervention; C: comparator; O: outcomes) questions to guide the development of recommendations on response interventions during the early/intermediate and late emergency phases and on risk communications for mitigating psycho-social impact of radiation emergencies. For each PICO question, an extensive evidence search and systematic review was conducted. The GDG then formulated the recommendations using the evidence to recommendation (E-2-R) decision-making matrix and evaluated the strength of each recommendation. (authors)

Development of a Fibre-Phased Array Laser-EMAT Ultrasonic System for Defect Inspection

International Nuclear Information System (INIS)

Pei, C; Demachi, K; Koyama, K; Uesaka, M; Fukuchi, T; Chen, Z

2014-01-01

In this work, a phased array laser ultrasound system with using fibre optic delivery and a custom-designed focusing objective lens has been developed for enhancing the ultrasound generation. The fibre-phased array method is applied to improve the sensitivity and detecting ability of the laser-EMAT system for defect inspection

Study on Risk Approaches in Software Development Projects

Directory of Open Access Journals (Sweden)

Claudiu BRANDAS

2012-01-01

Full Text Available Risk approaches in project development led to the integration in the IT project management methodologies and software development of activities and processes of risk management. The diversity and the advanced level of the used technologies in IT projects with increasing com-plexity leads to an exponential diversification of risk factors.The purpose of this research is to identify the level of the risk approach in IT projects both at the IT project management and software development methodologies level and the level of the perception of IT project man-agers, IT managers and IT analysts in Romanian IT companies. Thus, we want to determine the correlation between the use of a project management or software development methodology and the overall level of risk perceived by the project managers using these methodologies.

Developing a Dual-Level Capabilities Approach: Using Constructivist Grounded Theory and Feminist Ethnography to Enhance the Capabilities Approaches

Science.gov (United States)

Hall, Kia M. Q.

2014-01-01

In this study, a dual-level capabilities approach to development is introduced. This approach intends to improve upon individual-focused capabilities approaches developed by Amartya Sen and Martha Nussbaum. Based upon seven months of ethnographic research in the Afro-descendant, autochthonous Garifuna community of Honduras, constructivist grounded…

Phase equilibria and thermodynamic properties of high-alloy tool steels : theoretical and experimental approach

OpenAIRE

Bratberg, Johan

2005-01-01

The recent development of tool steels and high-speed steels has led to a significant increase in alloy additions, such as Co, Cr, Mo, N, V, and W. Knowledge about the phase relations in these multicomponent alloys, that is, the relative stability between different carbides or the solubility of different elements in the carbides and in the matrix phase, is essential for understanding the behaviour of these alloys in heat treatments. This information is also the basis for improving the properti...

Modelling and numerical simulation of two-phase flows using the two-fluid two-pressure approach; Modelisation et simulation numerique des ecoulements diphasiques par une approche bifluide a deux pressions

Energy Technology Data Exchange (ETDEWEB)

Guillemaud, V

2007-03-15

This thesis is devoted to the modelling and numerical simulation of liquid-vapor flows. In order to describe these phase transition flows, a two-fluid two-pressure approach is considered. This description of the liquid-vapor mixing is associated to the seven-equation model introduced by Baer and Nunziato. This work investigates the properties of this model in order to simulate the phase transition flows occurring in nuclear engineering. First, a theoretical thermodynamic framework is constructed to describe the liquid-vapor mixing. Provided with this framework, various modelling choices are suggested for the interaction terms between the phases. These closure laws comply with an entropy inequality. The mathematical properties of this model are thereafter examined. The convective part is associated to a nonconservative hyperbolic system. First, we focus on the definition of its weak solutions. Several flow regimes for the two-phase mixing derive from this analysis. Such regimes for the two-phase flows are analogous to the torrential and fluvial regimes for the shallow-water equations. Furthermore, we establish the linear and nonlinear stabilities of the liquid-vapor equilibrium. Finally, the implementation of a turbulence model and the introduction of a reconstruction process for the interfacial area are investigated in order to refine the description of the interfacial transfers. Using a fractional step approach, a Finite Volume method is at last constructed to simulate this model. First, various nonconservative adaptations of standard Riemann solvers are developed to approach the convective part. Unlike the classic nonconservative framework, these schemes converge towards the same solution. Furthermore, a new relaxation scheme is proposed to approach the interfacial transfers. Provided with these schemes, the whole numerical method preserves the liquid-vapor equilibria. Using this numerical method, a careful comparison between the one- and two-pressure two

Strain mapping of LED devices by dark-field inline electron holography: Comparison between deterministic and iterative phase retrieval approaches

Energy Technology Data Exchange (ETDEWEB)

Song, Kyung; Shin, Ga-Young; Kim, Jong Kyu [Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31 Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Oh, Sang Ho, E-mail: shoh@postech.ac.kr [Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31 Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Koch, Christoph T. [Institute for Experimental Physics, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm (Germany)

2013-04-15

Dark-field inline electron holography has recently been established as a convenient method to map strain in semiconductor devices, combining high precision, low noise, sub-nm spatial resolution and fields-of-view larger than 1 μm. Here we compare two approaches to reconstruct the geometric phase from a transmission electron microscopy dark-field focal series and their effects on the strain measurement: the transport-of-intensity-equation (TIE) and a flux-preserving iterative approach. For this task, we used a GaN-based light emitting diode with a highly complex heterostructure as a model system. While the TIE relies on 3 images only but requires the optimization of two free parameters (defocus step and low-limit cut-off frequency), the iterative reconstruction algorithm involves no adjustable parameters and uses images recorded at 9 different planes of focus with quadratically increasing defocus values. Optimum parameters for the TIE-reconstruction could be identified. However, the iterative phase retrieval approach yields the strain values that agree best with the expected strain levels and provides also higher spatial resolution.

Development of high resolution Michelson interferometer for stable phase-locked ultrashort pulse pair generation.

Science.gov (United States)

Okada, Takumi; Komori, Kazuhiro; Goshima, Keishiro; Yamauchi, Shohgo; Morohashi, Isao; Sugaya, Takeyoshi; Ogura, Mutsuo; Tsurumachi, Noriaki

2008-10-01

We developed a high resolution Michelson interferometer with a two-frequency He-Ne laser positioning system in order to stabilize the relative phase of a pulse pair. The control resolution corresponded to a 12 as time resolution or a phase of 1.5 degrees at 900 nm. This high resolution Michelson interferometer can generate a phase-locked pulse pair either with a specific relative phase such as 0 or pi radians or with an arbitrary phase. Coherent control of an InAs self-assembled quantum dot was demonstrated using the high resolution Michelson interferometer with a microspectroscopy system.

A plant control system development approach for IRIS

International Nuclear Information System (INIS)

Wood, R.T.; Brittain, C.R.; March-Leuba, J.A.; Conway, L.E.; Oriani, L.

2003-01-01

The plant control system concept for the International Reactor Innovative and Secure (IRIS) will make use of integrated control, diagnostic, and decision modules to provide a highly automated intelligent control capability. The plant control system development approach established for IRIS involves determination and verification of control strategies based on whole-plant simulation; identification of measurement, control, and diagnostic needs; development of an architectural framework in which to integrate an intelligent plant control system; and design of the necessary control and diagnostic elements for implementation and validation. This paper describes key elements of the plant control system development approach established for IRIS and presents some of the strategies and methods investigated to support the desired control capabilities. (author)

Development of a single-phase 30 m HTS power cable

Science.gov (United States)

Cho, Jeonwook; Bae, Joon-Han; Kim, Hae-Jong; Sim, Ki-Deok; Kim, Seokho; Jang, Hyun-Man; Lee, Chang-Young; Kim, Dong-Wook

2006-05-01

HTS power transmission cables appear to be the replacement and retrofitting of underground cables in urban areas and HTS power transmission cable offers a number of technical and economic merits compared to the normal conductor cable system. A 30 m long, single-phase 22.9 kV class HTS power transmission cable system has been developed by Korea Electrotechnology Research Institute (KERI), LS Cable Ltd., and Korea Institute of Machinery and Materials (KIMM), which is one of the 21st century frontier project in Korea since 2001. The HTS power cable has been developed, cooled down and tested to obtain realistic thermal and electrical data on HTS power cable system. The evaluation results clarified such good performance of HTS cable that DC critical current of the HTS cable was 3.6 kA and AC loss was 0.98 W/m at 1260 Arms and shield current was 1000 Arms. These results proved the basic properties for 22.9 kV HTS power cable. As a next step, we have been developing a 30 m, three-phase 22.9 kV, 50 MV A HTS power cable system and long term evaluation is in progress now.

An Overview of SBIR Phase 2 Communications Technology and Development

Science.gov (United States)

Nguyen, Hung D.; Steele, Gynelle C.

2015-01-01

Technological innovation is the overall focus of NASA's Small Business Innovation Research (SBIR) program. The program invests in the development of innovative concepts and technologies to help NASA's mission directorates address critical research and development needs for agency projects. This report highlights innovative SBIR Phase II projects from 2007-2012 specifically addressing areas in Communications Technology and Development which is one of six core competencies at NASA Glenn Research Center. There are eighteen technologies featured with emphasis on a wide spectrum of applications such as with a security-enhanced autonomous network management, secure communications using on-demand single photons, cognitive software-defined radio, spacesuit audio systems, multiband photonic phased-array antenna, and much more. Each article in this booklet describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report serves as an opportunity for NASA personnel including engineers, researchers, and program managers to learn of NASA SBIR's capabilities that might be crosscutting into this technology area. As the result, it would cause collaborations and partnerships between the small companies and NASA Programs and Projects resulting in benefit to both SBIR companies and NASA.

Development of andrographolide molecularly imprinted polymer for solid-phase extraction

Science.gov (United States)

Yin, Xiaoying; Liu, Qingshan; Jiang, Yifan; Luo, Yongming

2011-06-01

A method employing molecularly imprinted polymer (MIP) as selective sorbent for solid-phase extraction (SPE) to pretreat samples was developed. The polymers were prepared by precipitation polymerization with andrographolide as template molecule. The structure of MIP was characterized and its static adsorption capacity was measured by the Scatchard equation. In comparison with C 18-SPE and non-imprinted polymer (NIP) SPE column, MIP-SPE column displays high selectivity and good affinity for andrographolide and dehydroandrographolide for extract of herb Andrographis paniculata ( Burm.f.) Nees (APN). MIP-SPE column capacity was 11.9 ± 0.6 μmol/g and 12.1 ± 0.5 μmol/g for andrographolide and dehydroandrographolide, respectively and was 2-3 times higher than that of other two columns. The precision and accuracy of the method developed were satisfactory with recoveries between 96.4% and 103.8% (RSD 3.1-4.3%, n = 5) and 96.0% and 104.2% (RSD 2.9-3.7%, n = 5) for andrographolide and dehydroandrographolide, respectively. Various real samples were employed to confirm the feasibility of method. This developed method demonstrates the potential of molecularly imprinted solid phase extraction for rapid, selective, and effective sample pretreatment.

Micelle assisted thin-film solid phase microextraction: a new approach for determination of quaternary ammonium compounds in environmental samples.

Science.gov (United States)

Boyacı, Ezel; Pawliszyn, Janusz

2014-09-16

Determination of quaternary ammonium compounds (QACs) often is considered to be a challenging undertaking owing to secondary interactions of the analytes' permanently charged quaternary ammonium head or hydrophobic tail with the utilized labware. Here, for the first time, a micelle assisted thin-film solid phase microextraction (TF-SPME) using a zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) as a matrix modifier is introduced as a novel approach for in-laboratory sample preparation of the challenging compounds. The proposed micelle assisted TF-SPME method offers suppression/enhancement free electrospray ionization of analytes in mass spectrometric detection, minimal interaction of the micelles with the TF-SPME coating, and chromatographic stationary phase and analysis free of secondary interactions. Moreover, it was found that the matrix modifier has multiple functions; when its concentration is found below the critical micelle concentration (CMC), the matrix modifier primarily acts as a surface deactivator; above its CMC, it acts as a stabilizer for QACs. Additionally, shorter equilibrium extraction times in the presence of the modifier demonstrated that micelles also assist in the transfer of analytes from the bulk of the sample to the surface of the coating. The developed micelle assisted TF-SPME protocol using the 96-blade system requires only 30 min of extraction and 15 min of desorption. Together with a conditioning step (15 min), the entire method is 60 min; considering the advantage of using the 96-blade system, if all the blades in the brush are used, the sample preparation time per sample is 0.63 min. Moreover, the recoveries for all analytes with the developed method were found to range within 80.2-97.3%; as such, this method can be considered an open bed solid phase extraction. The proposed method was successfully validated using real samples.

Auroral Substorms: Search for Processes Causing the Expansion Phase in Terms of the Electric Current Approach

Science.gov (United States)

Akasofu, Syun-Ichi

2017-10-01

Auroral substorms are mostly manifestations of dissipative processes of electromagnetic energy. Thus, we consider a sequence of processes consisting of the power supply (dynamo), transmission (currents/circuits) and dissipations (auroral substorms-the end product), namely the electric current line approach. This work confirms quantitatively that after accumulating magnetic energy during the growth phase, the magnetosphere unloads the stored magnetic energy impulsively in order to stabilize itself. This work is based on our result that substorms are caused by two current systems, the directly driven (DD) current system and the unloading system (UL). The most crucial finding in this work is the identification of the UL (unloading) current system which is responsible for the expansion phase. A very tentative sequence of the processes leading to the expansion phase (the generation of the UL current system) is suggested for future discussions. (1) The solar wind-magnetosphere dynamo enhances significantly the plasma sheet current when its power is increased above 10^{18} erg/s (10^{11} w). (2) The magnetosphere accumulates magnetic energy during the growth phase, because the ionosphere cannot dissipate the increasing power because of a low conductivity. As a result, the magnetosphere is inflated, accumulating magnetic energy. (3) When the power reaches 3-5× 10^{18} erg/s (3-5× 10^{11} w) for about one hour and the stored magnetic energy reaches 3-5×10^{22} ergs (10^{15} J), the magnetosphere begins to develop perturbations caused by current instabilities (the current density {≈}3× 10^{-12} A/cm2 and the total current {≈}106 A at 6 Re). As a result, the plasma sheet current is reduced. (4) The magnetosphere is thus deflated. The current reduction causes partial B/partial t > 0 in the main body of the magnetosphere, producing an earthward electric field. As it is transmitted to the ionosphere, it becomes equatorward-directed electric field which drives both

Entropy, free energy and phase transitions in the lattice Lotka-Volterra model

International Nuclear Information System (INIS)

Chichigina, O. A.; Tsekouras, G. A.; Provata, A.

2006-01-01

A thermodynamic approach is developed for reactive dynamic models restricted to substrates of arbitrary dimensions, including fractal substrates. The thermodynamic formalism is successfully applied to the lattice Lotka-Volterra (LLV) model of autocatalytic reactions on various lattice substrates. Different regimes of reactions described as phases, and phase transitions, are obtained using this approach. The predictions of thermodynamic theory confirm extensive numerical kinetic Monte Carlo simulations on square and fractal lattices. Extensions of the formalism to multispecies LLV models are also presented

A systematic approach for component-based software development

NARCIS (Netherlands)

Guareis de farias, Cléver; van Sinderen, Marten J.; Ferreira Pires, Luis

2000-01-01

Component-based software development enables the construction of software artefacts by assembling prefabricated, configurable and independently evolving building blocks, called software components. This paper presents an approach for the development of component-based software artefacts. This

Phase sensitive multichannel OCT

International Nuclear Information System (INIS)

Trasischker, W.

2015-01-01

The main aim of this thesis was to develop and improve phase sensitive, multichannel methods for optical coherence tomography (OCT) using light in the 840 nm and 1040 nm regime. Conventional OCT provides purely structural information by illuminating the sample by one beam and recording the backscattered signal with one detection channel. Combination of this approach with a raster scan enables the acquisition of 2D and 3D structural information with a resolution in the micrometer regime. However, sometimes additional image contrast or information is desired. Amongst other approaches, this can be provided by a phase sensitive analysis of the interference pattern. Combining phase sensitivity with the illumination of the sample by more than one beam and/or by recording the data using more than one data acquisition channel allows for even more enhanced imaging. While phase sensitive OCT gives access to additional contrast and information, multichannel OCT can provide higher imaging speed, scan eld size and exible dierential measurements. Amongst the dierential, phase sensitive approaches, Doppler OCT (DOCT) and polarization sensitive OCT (PS-OCT) are two of the most promising OCT modalities. While the former targets information on the movement of backscattering particles, the latter measures alterations of the polarization state of the light induced by the sample. Both techniques provide additional image contrast and are, due to the non-invasive and fast character of OCT, well suited for in vivo imaging of the human eye. In the course of this thesis, two dierent multichannel, phase sensitive OCT systems will be presented. First, a D-OCT system with three dierent sampling beams is described. With a central wavelength of 840 nm these three beams are emitted by three individual laser sources. This eectively eliminates any cross talk and provides the full depth range for each channel. Furthermore, by illuminating the sample from three dierent directions, the absolute

Subscale Water Based Phase Change Material Heat Exchanger Development

Science.gov (United States)

Sheth, Rubik; Hansen, Scott

2016-01-01

Supplemental heat rejection devices are required in many spacecraft as the radiators are not sized to meet the full heat rejection demand. One means of obtaining additional heat rejection is through the use of phase change material heat exchangers (PCM HX's). PCM HX's utilize phase change to store energy in unfavorable thermal environments (melting) and reject the energy in favorable environments (freezing). Traditionally, wax has been used as a PCM on spacecraft. However, water is an attractive alternative because it is capable of storing about 40% more energy per unit mass due to its higher latent heat of fusion. The significant problem in using water as a PCM is its expansion while freezing, leading to structural integrity concerns when housed in an enclosed heat exchanger volume. Significant investigation and development has taken place over the past five years to understand and overcome the problems associated with water PCM HX's. This paper reports on the final efforts by Johnson Space Center's Thermal Systems Branch to develop a water based PCM HX. The test article developed and reported on is a subscale version of the full-scale water-based PCM HX's constructed by Mezzo Technologies. The subscale unit was designed by applying prior research on freeze front propagation and previous full-scale water PCM HX development. Design modifications to the subscale unit included use of urethane bladder, decreased aspect ratio, perforated protection sheet, and use of additional mid-plates. Testing of the subscale unit was successful and 150 cycles were completed without fail.

TALENT MANAGEMENT: A NOVEL APPROACH FOR DEVELOPING INNOVATIVE SOLUTIONS TOWARDS HERITAGE COMMUNITIES DEVELOPMENT

Directory of Open Access Journals (Sweden)

Mohamed Hesham Madbouly Hussein Khalil

2017-11-01

Full Text Available Heritage communities in Egypt have continuously developed to sustain a history of millenniums. Developments have been focused on sustaining the physical heritage such as buildings and cities, yet ignoring the intangible heritage such as stories, memories and traditions of people. The results are deterioration of the developed physical heritage as a natural response of ignorance. Architectural Design Firms (ADFs are responsible for developing innovative solutions that translate intangible heritage into sustainable projects. Such solutions require talented architects who are in need of being treated in a talented manner. Therefore, this paper aims to investigate the role of Talent Management (TM as a novel approach for developing innovative solutions for Egyptian heritage communities’ development. In order to achieve this aim, a qualitative approach based on (1 literature review is used to investigate heritage development, creative industries, ADFs, motivation and TM and (2 a case study is collected and analysed to study the relationship between TM and intangible heritage preservation.

A new approach to calculating the Berry phase

International Nuclear Information System (INIS)

Wu Lianao; Sun Jing; Zhong Jiyu

1993-01-01

It is proved that any time-dependent problem can be transformed into a time-independent one by a unitary transformation. The general equation satisfied by the transformation is given. For some time-dependent Hamiltonians the transformation can be found easily. More importantly, if the initial states are just eigenstates of the transformed Hamiltonians, the dynamical phase can be conveniently removed and the Berry phase can be found directly. (orig.)

An induction Linac approach to phase rotation of a muon bunch in the production region of μ+-μ- colliders

International Nuclear Information System (INIS)

Turner, W.C.

1995-01-01

The possibility of using an induction linac for phase rotation, or equivalently flattening the head to tail mean energy sweep, of a muon bunch in the production region of a μ + - μ - is examined. Axial spreading of an accelerating bunch is analyzed and the form of appropriate induction cell voltage waveforms is derived. A set of parametric equations for the induction accelerator structure is given and specific solutions are presented which demonstrate the technological feasibility of the induction linac approach to phase rotation

Phase transitions: the lattice QCD approach

International Nuclear Information System (INIS)

Gavai, R.V.

1986-01-01

Recent results in the field of finite temperature lattice quantum chromodynamics (QCD) are presented with special emphasis on comparison of the different methods used to incorporate the dynamical fermions. Attempts to obtain a nonperturbative estimate of the velocity of sound in both the hadronic and quark-gluon phase are summarized along with the results. 15 refs., 7 figs

Correlation between auroral activity and rate of development of a storm in its main phase

Directory of Open Access Journals (Sweden)

Boroyev R.N.

2016-12-01

Full Text Available We investigated the relationship between the rate of storm development in its main phase (|ΔDst|/ΔT and the average value (ΣAE/ΔT of AE index for the main phase where |ΔDst| is the Dst-index variation, ΣAE is the total value of AE index for the main phase of magnetic storm, ΔT is the main phase duration. We considered storms initiated by corotating interaction region (CIR and interplanetary coronal mass ejection (ICME (magnetic cloud and ejecta. For CIR events, the value of ΣAE/ΔT is shown to correlate with the rate of storm development in its main phase in contrast to the storms initiated by the ICME. As found, there is a weak correlation between ΣAE/ΔT and the minimum value of Dst index for CIR and ICME events.

Biomass power for rural development. Technical progress report Phase-II. Contractual reporting period October-December 1999

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, Edward; The Salix Consortium

2000-03-23

The project undertaken by the Salix Consortium is a multi-phased, multi-partner endeavor. Phase 1 focused on initial development and testing of the technology and forging the necessary agreements to demonstrate commercial willow production. The Phase 1 objectives have been successfully completed: preparing design plans for 2 utility pulverized coal boilers for 20 MW of biopower capacity; developing fuel supply plans for the project with a goal of establishing 365 ha (900 ac) of willow; obtaining power production commitments from the power companies for Phase 2; obtaining construction and environmental permits; and developing an experimental strategy for crop production and power generation improvements needed to assure commercial success. The R and D effort also addresses environmental issues pertaining to introduction of the willow energy system.

Integrating health economics modeling in the product development cycle of medical devices: a Bayesian approach.

Science.gov (United States)

Vallejo-Torres, Laura; Steuten, Lotte M G; Buxton, Martin J; Girling, Alan J; Lilford, Richard J; Young, Terry

2008-01-01

Medical device companies are under growing pressure to provide health-economic evaluations of their products. Cost-effectiveness analyses are commonly undertaken as a one-off exercise at the late stage of development of new technologies; however, the benefits of an iterative use of economic evaluation during the development process of new products have been acknowledged in the literature. Furthermore, the use of Bayesian methods within health technology assessment has been shown to be of particular value in the dynamic framework of technology appraisal when new information becomes available in the life cycle of technologies. In this study, we set out a methodology to adapt these methods for their application to directly support investment decisions in a commercial setting from early stages of the development of new medical devices. Starting with relatively simple analysis from the very early development phase and proceeding to greater depth of analysis at later stages, a Bayesian approach facilitates the incorporation of all available evidence and would help companies to make better informed choices at each decision point.

New 'phase' of quantum gravity.

Science.gov (United States)

Wang, Charles H-T

2006-12-15

The emergence of loop quantum gravity over the past two decades has stimulated a great resurgence of interest in unifying general relativity and quantum mechanics. Among a number of appealing features of this approach is the intuitive picture of quantum geometry using spin networks and powerful mathematical tools from gauge field theory. However, the present form of loop quantum gravity suffers from a quantum ambiguity, owing to the presence of a free (Barbero-Immirzi) parameter. Following the recent progress on conformal decomposition of gravitational fields, we present a new phase space for general relativity. In addition to spin-gauge symmetry, the new phase space also incorporates conformal symmetry making the description parameter free. The Barbero-Immirzi ambiguity is shown to occur only if the conformal symmetry is gauge fixed prior to quantization. By withholding its full symmetries, the new phase space offers a promising platform for the future development of loop quantum gravity. This paper aims to provide an exposition, at a reduced technical level, of the above theoretical advances and their background developments. Further details are referred to cited references.

Motivation and participation in a phase III cardiac rehabilitation programme: an application of the health action process approach.

Science.gov (United States)

Dohnke, Birte; Nowossadeck, Enno; Müller-Fahrnow, Werner

2010-10-01

This longitudinal study extends the previous research on low participation rates and high dropout rates in phase III cardiac rehabilitation (CR) exercise programmes. It examines the correlates of motivation and participation 6 months after inpatient phase II CR (T1) and the predictors of dropout 6 months later (T2) using the health action process approach (HAPA). Risk perception, outcome expectancies, self-efficacy, intention (at T1), and participation (at T1 and T2) in relation to phase III CR programmes was assessed in 456 patients. Based on intention and participation at T1, patients were classified as nonintenders (56%), intenders (13%), or actors (31%). Group differences were confirmed in outcome expectancies and self-efficacy. By T2, 21% of T1 actors had dropped out. Dropouts and maintainers differed in intention and self-efficacy (at T1). Results are in line with the HAPA and suggest a perspective for tailoring motivational counselling to improve participation in phase III CR programmes.

An integrated Boltzmann+hydrodynamics approach to heavy ion collisions

International Nuclear Information System (INIS)

Petersen, Hannah

2009-01-01

In this thesis the first fully integrated Boltzmann+hydrodynamics approach to relativistic heavy ion reactions has been developed. After a short introduction that motivates the study of heavy ion reactions as the tool to get insights about the QCD phase diagram, the most important theoretical approaches to describe the system are reviewed. The hadron-string transport approach that this work is based on is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) approach. Predictions for the charged particle multiplicities at LHC energies are made. The next step is the development of a new framework to calculate the baryon number density in a transport approach. Time evolutions of the net baryon number and the quark density have been calculated at AGS, SPS and RHIC energies. Studies of phase diagram trajectories using hydrodynamics are performed. The hybrid approach that has been developed as the main part of this thesis is based on the UrQMD transport approach with an intermediate hydrodynamical evolution for the hot and dense stage of the collision. The full (3+1) dimensional ideal relativistic one fluid dynamics evolution is solved using the SHASTA algorithm. Three different equations of state have been used, namely a hadron gas equation of state without a QGP phase transition, a chiral EoS and a bag model EoS including a strong first order phase transition. For the freeze-out transition from hydrodynamics to the cascade calculation two different set-ups are employed. The parameter dependences of the model are investigated and the time evolution of different quantities is explored. The hybrid model calculation is able to reproduce the experimentally measured integrated as well as transverse momentum dependent v 2 values for charged particles. The multiplicity and mean transverse mass excitation function is calculated for pions, protons and kaons in the energy range from E lab =2-160 A GeV. The HBT correlation of the negatively charged pion source created in

An integrated Boltzmann+hydrodynamics approach to heavy ion collisions

Energy Technology Data Exchange (ETDEWEB)

Petersen, Hannah

2009-04-22

In this thesis the first fully integrated Boltzmann+hydrodynamics approach to relativistic heavy ion reactions has been developed. After a short introduction that motivates the study of heavy ion reactions as the tool to get insights about the QCD phase diagram, the most important theoretical approaches to describe the system are reviewed. The hadron-string transport approach that this work is based on is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) approach. Predictions for the charged particle multiplicities at LHC energies are made. The next step is the development of a new framework to calculate the baryon number density in a transport approach. Time evolutions of the net baryon number and the quark density have been calculated at AGS, SPS and RHIC energies. Studies of phase diagram trajectories using hydrodynamics are performed. The hybrid approach that has been developed as the main part of this thesis is based on the UrQMD transport approach with an intermediate hydrodynamical evolution for the hot and dense stage of the collision. The full (3+1) dimensional ideal relativistic one fluid dynamics evolution is solved using the SHASTA algorithm. Three different equations of state have been used, namely a hadron gas equation of state without a QGP phase transition, a chiral EoS and a bag model EoS including a strong first order phase transition. For the freeze-out transition from hydrodynamics to the cascade calculation two different set-ups are employed. The parameter dependences of the model are investigated and the time evolution of different quantities is explored. The hybrid model calculation is able to reproduce the experimentally measured integrated as well as transverse momentum dependent v{sub 2} values for charged particles. The multiplicity and mean transverse mass excitation function is calculated for pions, protons and kaons in the energy range from E{sub lab}=2-160 A GeV. The HBT correlation of the negatively charged pion source