Engaged Problem Formulation in IS Research
DEFF Research Database (Denmark)
Nielsen, Peter Axel; Persson, John Stouby
2016-01-01
problems requires a more substantial engagement with the different stakeholders, especially when their problems are ill structured and situated in complex organizational settings. On this basis, we present an engaged approach to formulating IS problems with, not for, IS practitioners. We have come...
Ising formulations of many NP problems
Lucas, Andrew
2013-01-01
We provide Ising formulations for many NP-complete and NP-hard problems, including all of Karp's 21 NP-complete problems. This collects and extends mappings to the Ising model from partitioning, covering and satisfiability. In each case, the required number of spins is at most cubic in the size of the problem. This work may be useful in designing adiabatic quantum optimization algorithms.
Ising formulations of many NP problems
Directory of Open Access Journals (Sweden)
Andrew eLucas
2014-02-01
Full Text Available We provide Ising formulations for many NP-complete and NP-hard problems, including all of Karp's 21 NP-complete problems. This collects and extends mappings to the Ising model from partitioning, covering and satisfiability. In each case, the required number of spins is at most cubic in the size of the problem. This work may be useful in designing adiabatic quantum optimization algorithms.
Engaged Problem Formulation in IS Research
DEFF Research Database (Denmark)
Nielsen, Peter Axel; Persson, John Stouby
2016-01-01
“Is this the problem?”: the question that haunts many information systems (IS) researchers when they pursue work relevant to both practice and research. Nevertheless, a deliberate answer to this question requires more than simply asking the involved IS practitioners. Deliberately formulating...
Problem formulation as a discursive design activity
DEFF Research Database (Denmark)
Hansen, Claus Thorp; Dorst, Kees; Andreasen, Mogens Myrup
2009-01-01
In the design methodology literature, design is often described as a rational problem solving process. This approach has been very successful; it has lead to the creation of design process models, tools, methods and techniques. Design methods teaching along these lines has become an indispensable...... part of any engineering design education. Yet the assumptions behind the rational problem solving approach to design do not sit well with some of the experiences we have in design teaching and design practice. Problem formulation is one such area where we might have to look for a different way...... to describe what is happening in design, beyond the problem solving approach. In this paper an extensive educational case study will be used to see whether a framework for describing design as a discursive activity (based on the notions of ‘discourse’ and ‘paradox’) could be more appropriate to describe...
Engaged Problem Formulation of IT Management in Danish Municipalities
DEFF Research Database (Denmark)
Nielsen, Peter Axel; Persson, John Stouby
2012-01-01
Municipalities’ effectiveness in managing information technology (IT) is increasingly important in adhering to their responsibilities for providing services to citizens. While the municipalities’ difficulty in managing IT has been well documented, it is more elusive what specific problems are most...... relevant in contemporary municipal IT management practice. On this basis, we present an engaged scholarship approach to formulate IT management problems together with municipalities - not for municipalities. We have come to understand such engaged problem formulation as joint researching and defining...... of a contemporary and complex problem by researchers and those who experience and know the problem. We present the formulated IT management problems and discuss the engaged problem formulation process in relation to engaged scholarship. Furthermore, we discuss how engaged problem formulation may contribute...
A displacement based FE formulation for steady state problems
Yu, Y.
2005-01-01
In this thesis a new displacement based formulation is developed for elasto-plastic deformations in steady state problems. In this formulation the displacements are the primary variables, which is in contrast to the more common formulations in terms of the velocities as the primary variables. In a
High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation
DEFF Research Database (Denmark)
Dimzon, Ian Ken; Trier, Xenia; Frömel, Tobias
2016-01-01
High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid o......-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health. Graphical Abstract ᅟ....
Validation of flexible multibody dynamics beam formulations using benchmark problems
Bauchau, O.A.; Wu, Genyong; Betsch, P.; Cardona, A.; Gerstmayr, J.; Jonker, Jan B.; Masarati, P.; Sonneville, V.
2016-01-01
As the need to model flexibility arose in multibody dynamics, the floating frame of reference formulation was developed, but this approach can yield inaccurate results when elastic displacements becomes large. While the use of three-dimensional finite element formulations overcomes this problem, the
Validation of flexible multibody dynamics beam formulations using benchmark problems
Energy Technology Data Exchange (ETDEWEB)
Bauchau, Olivier A., E-mail: obauchau@umd.edu [University of Maryland (United States); Betsch, Peter [Karlsruhe Institute of Technology (Germany); Cardona, Alberto [CIMEC (UNL/Conicet) (Argentina); Gerstmayr, Johannes [Leopold-Franzens Universität Innsbruck (Austria); Jonker, Ben [University of Twente (Netherlands); Masarati, Pierangelo [Politecnico di Milano (Italy); Sonneville, Valentin [Université de Liège (Belgium)
2016-05-15
As the need to model flexibility arose in multibody dynamics, the floating frame of reference formulation was developed, but this approach can yield inaccurate results when elastic displacements becomes large. While the use of three-dimensional finite element formulations overcomes this problem, the associated computational cost is overwhelming. Consequently, beam models, which are one-dimensional approximations of three-dimensional elasticity, have become the workhorse of many flexible multibody dynamics codes. Numerous beam formulations have been proposed, such as the geometrically exact beam formulation or the absolute nodal coordinate formulation, to name just two. New solution strategies have been investigated as well, including the intrinsic beam formulation or the DAE approach. This paper provides a systematic comparison of these various approaches, which will be assessed by comparing their predictions for four benchmark problems. The first problem is the Princeton beam experiment, a study of the static large displacement and rotation behavior of a simple cantilevered beam under a gravity tip load. The second problem, the four-bar mechanism, focuses on a flexible mechanism involving beams and revolute joints. The third problem investigates the behavior of a beam bent in its plane of greatest flexural rigidity, resulting in lateral buckling when a critical value of the transverse load is reached. The last problem investigates the dynamic stability of a rotating shaft. The predictions of eight independent codes are compared for these four benchmark problems and are found to be in close agreement with each other and with experimental measurements, when available.
High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation
Dimzon, Ian Ken; Trier, Xenia; Frömel, Tobias; Helmus, Rick; Knepper, Thomas P.; de Voogt, Pim
2016-02-01
High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid of an instrument data processor. Highly accurate mass spectral data enabled the calculation of higher-order mass defects. The different plots of MW and the nth-order mass defects (up to n = 3) could aid in assessing the structure of the different repeating units and estimating their absolute and relative number per molecule. The three major repeating units were -C2H4O-, -C2F4O-, and -CF2O-. Tandem MS was used to identify the end groups that appeared to be phosphates, as well as the possible distribution of the repeating units. Reversed-phase HPLC separated of the polymer molecules on the basis of number of nonpolar repeating units. The elucidated structure resembles the structure in the published manufacturer technical data. This analytical approach to the characterization of a PFPE-based formulation can serve as a guide in analyzing not just other PFPE-based formulations but also other fluorinated and non-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health.
Formulated linear programming problems from game theory and its ...
African Journals Online (AJOL)
Formulated linear programming problems from game theory and its computer implementation using Tora package. ... Game theory, a branch of operations research examines the various concepts of decision ... AJOL African Journals Online.
IRIS Assessment Plan for Uranium (Scoping and Problem Formulation Materials)
In January 2018, EPA released the IRIS Assessment Plan for Uranium (Oral Reference Dose) (Scoping and Problem Formulation Materials). An IRIS Assessment Plan (IAP) communicates to the public the plan for assessing each individual chemical and includes summary informatio...
Improvability of assembly systems I: Problem formulation and performance evaluation
Directory of Open Access Journals (Sweden)
S.-Y. Chiang
2000-01-01
Full Text Available This work develops improvability theory for assembly systems. It consists of two parts. Part I includes the problem formulation and the analysis technique. Part II presents the so-called improvability indicators and a case study.
Very low resolution face recognition problem.
Zou, Wilman W W; Yuen, Pong C
2012-01-01
This paper addresses the very low resolution (VLR) problem in face recognition in which the resolution of the face image to be recognized is lower than 16 × 16. With the increasing demand of surveillance camera-based applications, the VLR problem happens in many face application systems. Existing face recognition algorithms are not able to give satisfactory performance on the VLR face image. While face super-resolution (SR) methods can be employed to enhance the resolution of the images, the existing learning-based face SR methods do not perform well on such a VLR face image. To overcome this problem, this paper proposes a novel approach to learn the relationship between the high-resolution image space and the VLR image space for face SR. Based on this new approach, two constraints, namely, new data and discriminative constraints, are designed for good visuality and face recognition applications under the VLR problem, respectively. Experimental results show that the proposed SR algorithm based on relationship learning outperforms the existing algorithms in public face databases.
Protecting the fast breeders: Problem formulation and effects analysis
International Nuclear Information System (INIS)
Oughton, D.H.
2003-01-01
Recent debates on protection of the environment from ionising radiation have reached reasonable agreement over the ethical and philosophical basis of environmental protection and a recognition that a practical system of protection will need to support (at a minimum) the principles of sustainable development, biodiversity, and conservation. However, there is still some controversy over the use of dose assessment tools within risk evaluation and management. The paper uses the case of the Dounreay 'radioactive rabbits' to discuss the advantages and limitations of proposed systems, focusing primarily on the interaction between ecological risk assessment (ERA) and the reference flora and fauna approach. It concludes that the reference approach is a valuable tool for the analysis of environmental effects, but that there is a problem if it becomes the driving force of the protection framework. In particular, there is a need for a clearer focus on non-technical issues within the problem formulation stage of ERA, particularly the social, ethical, political and economic issues, and there should be a strong commitment to stakeholder involvement at this stage. The problem formulation stage should identify the relevant assessment tools; the assessment tool should dictate neither the problem formulation nor the risk management. (author)
A new formulation of the linear sampling method: spatial resolution and post-processing
International Nuclear Information System (INIS)
Piana, M; Aramini, R; Brignone, M; Coyle, J
2008-01-01
A new formulation of the linear sampling method is described, which requires the regularized solution of a single functional equation set in a direct sum of L 2 spaces. This new approach presents the following notable advantages: it is computationally more effective than the traditional implementation, since time consuming samplings of the Tikhonov minimum problem and of the generalized discrepancy equation are avoided; it allows a quantitative estimate of the spatial resolution achievable by the method; it facilitates a post-processing procedure for the optimal selection of the scatterer profile by means of edge detection techniques. The formulation is described in a two-dimensional framework and in the case of obstacle scattering, although generalizations to three dimensions and penetrable inhomogeneities are straightforward
Symmetry Breaking in MILP Formulations for Unit Commitment Problems
Lima, Ricardo
2015-12-11
This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers.
Symmetry Breaking in MILP Formulations for Unit Commitment Problems
Lima, Ricardo; Novais, Augusto Q.
2015-01-01
This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers.
Implementing Problem Resolution Models in Remedy
Marquina, M A; Ramos, R
2000-01-01
This paper defines the concept of Problem Resolution Model (PRM) and describes the current implementation made by the User Support unit at CERN. One of the main challenges of User Support services in any High Energy Physics institute/organization is to address solving of the computing-relatedproblems faced by their researchers. The User Support group at CERN is the IT unit in charge of modeling the operations of the Help Desk and acts as asecond level support to some of the support lines whose problems are receptioned at the Help Desk. The motivation behind the use of a PRM is to provide well defined procedures and methods to react in an efficient way to a request for solving a problem,providing advice, information etc. A PRM is materialized on a workflow which has a set of defined states in which a problem can be. Problems move from onestate to another according to actions as decided by the person who is handling them. A PRM can be implemented by a computer application, generallyreferred to as Problem Report...
Problem-formulation and problem-solving in self-organized communities
DEFF Research Database (Denmark)
Foss, Nicolai J.; Frederiksen, Lars; Rullani, Francesco
2016-01-01
Building on the problem-solving perspective, we study behaviors related to projects and the communication-based antecedents of such behaviors in the free open-source software (FOSS) community. We examine two kinds of problem/project-behaviors: Individuals can set up projects around the formulation...
Putting problem formulation at the forefront of GMO risk analysis.
Tepfer, Mark; Racovita, Monica; Craig, Wendy
2013-01-01
When applying risk assessment and the broader process of risk analysis to decisions regarding the dissemination of genetically modified organisms (GMOs), the process has a tendency to become remarkably complex. Further, as greater numbers of countries consider authorising the large-scale dissemination of GMOs, and as GMOs with more complex traits reach late stages of development, there has been increasing concern about the burden posed by the complexity of risk analysis. We present here an improved approach for GMO risk analysis that gives a central role to problem formulation. Further, the risk analysis strategy has been clarified and simplified in order to make rigorously scientific risk assessment and risk analysis more broadly accessible to diverse stakeholder groups.
Hawthorne, Bryant; Panchal, Jitesh H.
2014-07-01
A bilevel optimization formulation of policy design problems considering multiple objectives and incomplete preferences of the stakeholders is presented. The formulation is presented for Feed-in-Tariff (FIT) policy design for decentralized energy infrastructure. The upper-level problem is the policy designer's problem and the lower-level problem is a Nash equilibrium problem resulting from market interactions. The policy designer has two objectives: maximizing the quantity of energy generated and minimizing policy cost. The stakeholders decide on quantities while maximizing net present value and minimizing capital investment. The Nash equilibrium problem in the presence of incomplete preferences is formulated as a stochastic linear complementarity problem and solved using expected value formulation, expected residual minimization formulation, and the Monte Carlo technique. The primary contributions in this article are the mathematical formulation of the FIT policy, the extension of computational policy design problems to multiple objectives, and the consideration of incomplete preferences of stakeholders for policy design problems.
On a covariant 2+2 formulation of the initial value problem in general relativity
International Nuclear Information System (INIS)
Smallwood, J.
1980-03-01
The initial value problems in general relativity are considered from a geometrical standpoint with especial reference to the development of a covariant 2+2 formalism in which space-time is foliated by space-like 2-surfaces under the headings; the Cauchy problem in general relativity, the covariant 3+1 formulation of the Cauchy problem, characteristic and mixed initial value problems, on locally imbedding a family of null hypersurfaces, the 2+2 formalism, the 2+2 formulation of the Cauchy problem, the 2+2 formulation of the characteristic and mixed initial value problems, and a covariant Lagrangian 2+2 formulation. (U.K.)
Formulation and solution of the classical seashell problem
International Nuclear Information System (INIS)
Illert, C.
1987-01-01
Despite an extensive scholarly literature dating back to classical times, seashell geometries have hiterto resisted rigorous theoretical analysis, leaving applied scientists to adopt a directionless empirical approach toward classification. The voluminousness of recent paleontological literature demonstrates the importance of this problem to applied scientists, but in no way reflects corresponding conceptual or theoretical advances beyond the XIX century thinking which was so ably summarized by Sir D'Arcy Wentworth Thompson in 1917. However, in this foundation paper for the newly emerging science of theoretical conchology, unifying theoretical considerations for the first time, permits a rigorous formulation and a complete solution of the problem of biological shell geometries. Shell coiling about the axis of symmetry can be deduced from first principles using energy considerations associated with incremental growth. The present paper shows that those shell apertures which are incurved (''cowrielike''), outflared (''stromblike'') or even backturned (''Opisthostomoidal'') are merely special cases of a much broader spectrum of ''allowable'' energy-efficient growth trajectories (tensile elastic clockspring spirals), many of which were widely used by Cretaceous ammonites. Energy considerations also dictate shell growth along the axis of symmetry, thus seashell spires can be understood in terms of certain special figures of revolution (Moebius elastic conoids), the better-known coeloconoidal and cyrtoconoidal shell spires being only two special cases arising from a whole class of topologically possible, energy efficient and biologically observed geometries. The ''wires'' and ''conoids'' of the present paper are instructive conceptual simplifications sufficient for present purposes. A second paper will later deal with generalized tubular surfaces in thre
Not your problem? Exploring the relationship between problem formulation and social responsibility
Directory of Open Access Journals (Sweden)
Sveinung Jørgensen
2011-05-01
Full Text Available This article explores the relationship between organizationalproblem formulation and social responsibility. Thepurpose of the article is to illuminate how organizationalproblem formulations (1 determine the manner in whichthe organization attempts to solve the problem and (2involve the ascription of significance to a group of stakeholdersseen as relevant for the organization. This has implicationsfor the degree to which they assume responsibilityfor those stakeholders. We discuss three dimensions ofresponsible decision making – rationality in goal attainment,reverence for ethical norms, and respect for stakeholders.Thereby, we arrive at an understanding of how differentorganizations in the same sector conceive of, andattempt to solve fundamental problems in the sector, aswell as how their assumed responsibility is reflected therein.We present and discuss a case that discusses keysimilarities and differences between two organizations inthe drug sector – a pharmaceutical company that producesmedicine for the treatment of drug addiction and a foundationworking with drug rehabilitation. We illuminatehow the two organizations base their activities on divergentformulations of the drug problem and how this ismanifested in their approach to the problem. We argue that this ultimately translates into differences in the inclusion of various stakeholdersin their problem space, and thereby the degree to which they assumeresponsibility for key stakeholders. This contributes to the corporate socialresponsibility literature by providing an in depth account of how problem formulationsshape organizational activities and determine the practical inclusionof stakeholders’ interests in the decisions and activities of organizations.
van Beurden, M.C.; Setija, Irwan
2017-01-01
We present two adapted formulations, one tailored to isotropic media and one for general anisotropic media, of the normal vector field framework previously introduced to improve convergence near arbitrarily shaped material interfaces in spectral simulation methods for periodic scattering geometries.
DEFF Research Database (Denmark)
Quaglia, Alberto; Sarup, Bent; Sin, Gürkan
2013-01-01
structure for efficient formulation of enterprise-wide optimization problems is presented. Through the integration of the described data structure in our synthesis and design framework, the problem formulation workflow is automated in a software tool, reducing time and resources needed to formulate large......The formulation of Enterprise-Wide Optimization (EWO) problems as mixed integer nonlinear programming requires collecting, consolidating and systematizing large amount of data, coming from different sources and specific to different disciplines. In this manuscript, a generic and flexible data...... problems, while ensuring at the same time data consistency and quality at the application stage....
Resolution for the Loviisa benchmark problem
International Nuclear Information System (INIS)
Garcia, C.R.; Quintero, R.; Milian, D.
1992-01-01
In the present paper, the Loviisa benchmark problem for cycles 11 and 8, and reactor blocks 1 and 2 from Loviisa NPP, is calculated. This problem user law leakage reload patterns and was posed at the second thematic group of TIC meeting held in Rheinsberg GDR, march 1989. SPPS-1 coarse mesh code has been used for the calculations
A duty-period-based formulation of the airline crew scheduling problem
Energy Technology Data Exchange (ETDEWEB)
Hoffman, K.
1994-12-31
We present a new formulation of the airline crew scheduling problem that explicitly considers the duty periods. We suggest an algorithm for solving the formulation by a column generation approach with branch-and-bound. Computational results are reported for a number of test problems.
An Evolutionary Formulation of the Crossing Number Problem
Directory of Open Access Journals (Sweden)
Che Sheng Gan
2009-01-01
Full Text Available A graph drawing algorithm is presented which results in complete graphs having minimum crossings equal to that of Guy's conjecture. It is then generalized and formulated in an evolutionary algorithm (EA to perform constrained search for the crossing numbers. The main objective of this work is to present a suitable two-dimensional scheme which can greatly reduce the complexity of finding crossing numbers by using computer. Program performance criteria are presented and discussed. It is shown that the EA implementation provides good confirmation of the predicted crossing numbers.
DEFF Research Database (Denmark)
Yoon, Gil Ho; Jensen, Jens Stissing; Sigmund, Ole
2007-01-01
given during the optimization process. In this paper we circumvent the explicit boundary representation by using a mixed finite element formulation with displacements and pressure as primary variables (a u/p-formulation). The Helmholtz equation is obtained as a special case of the mixed formulation...... for the elastic shear modulus equating to zero. Hence, by spatial variation of the mass density, shear and bulk moduli we are able to solve the coupled problem by the mixed formulation. Using this modelling approach, the topology optimization procedure is simply implemented as a standard density approach. Several...... two-dimensional acoustic-structure problems are optimized in order to verify the proposed method....
Resolution and optimization methods for tour planning problems
International Nuclear Information System (INIS)
Vasserot, Jean-Pierre
1976-12-01
The aim of this study is to describe computerized methods for the resolution of the computer supported tour planning problem. After a presentation of this problem in operational research, the different existing methods of resolution are reviewed with the different approaches which have led to their elaboration. Different critics and comparisons are made on these methods and some improvements and new procedures are proposed, some of them allowing to solve more general problems. Finally, the structure of such a program, made at the CII to solve this kind of problem under multiple constraints is analysed [fr
Proposition of a method to formulate idea and innovation problems
Directory of Open Access Journals (Sweden)
Stéphane GORIA
2010-01-01
Full Text Available Nowadays, innovation is a major stake for development and durability of many companies and institution’s activities. In our work, we are interested in interpersonal communication problem in innovation context. We focus on the upstream of innovation process and we consider the means that can be used. First to leverage organisation’s innovation perspective and second to solve innovation problem proposed by a strategic decision maker. To do this, we believe that people charge with solving an innovation problem should manage some difficulties: to identify what can be an innovation for the decision maker, to define the objects with a big innovation potential, communicate to his possible partners the innovation field to investigate and to find ideas to innovate etc. Then, we try to identify and to present these ideas to contribute to decision making process. At this time when the Web is really the universal source with access to formidable information quantities, we use it to establish some creativity and idea sources for innovation. This paper presents a method to solve these communication problems. It presents a tool box which potentialities are illustrated by an example of the management of a “new chair” development problem.
Problem Resolution through Electronic Mail: A Five-Step Model.
Grandgenett, Neal; Grandgenett, Don
2001-01-01
Discusses the use of electronic mail within the general resolution and management of administrative problems and emphasizes the need for careful attention to problem definition and clarity of language. Presents a research-based five-step model for the effective use of electronic mail based on experiences at the University of Nebraska at Omaha.…
A new formulation for the problem of fuel cell homogenization
International Nuclear Information System (INIS)
Chao, Y.-A.; Martinez, A.S.
1982-01-01
A new homogenization method for reactor cells is described. This new method consists in eliminating the NR approximation for the fuel resonance and the Wigner approximation for the resonance escape probability; the background cross section is then redefined and the problem studied is reanalyzed. (E.G.) [pt
An Integer Programming Formulation of the Minimum Common String Partition Problem.
Directory of Open Access Journals (Sweden)
S M Ferdous
Full Text Available We consider the problem of finding a minimum common string partition (MCSP of two strings, which is an NP-hard problem. The MCSP problem is closely related to genome comparison and rearrangement, an important field in Computational Biology. In this paper, we map the MCSP problem into a graph applying a prior technique and using this graph, we develop an Integer Linear Programming (ILP formulation for the problem. We implement the ILP formulation and compare the results with the state-of-the-art algorithms from the literature. The experimental results are found to be promising.
Gagliano, Caterina; Papa, Vincenzo; Amato, Roberta; Malaguarnera, Giulia; Avitabile, Teresio
2018-04-01
Purpose/aim of the study: The purpose of this study was to measure the pre-corneal retention time of two marketed formulations (eye drops and eye gel) of a steroid-antibiotic fixed combination (FC) containing 0.1% dexamethasone and 0.3% netilmicin. Pre-corneal retention time was evaluated in 16 healthy subjects using an ultrahigh-resolution anterior segment spectral domain optical coherence tomography (OCT). All subjects randomly received both formulations of the FC (Netildex, SIFI, Italy). Central tear film thickness (CTFT) was measured before instillation (time 0) and then after 1, 10, 20, 30, 40 50, 60 and 120 min. The pre-corneal retention time was calculated by plotting CTFT as a function of time. Differences between time points and groups were analyzed by Student's t-test. CTFT increased significantly after the instillation of the eye gel formulation (p < 0.001). CTFT reached its maximum value 1 min after instillation and returned to baseline after 60 min. No effect on CTFT was observed after the instillation of eye drops. The difference between the two formulations was statistically significant at time 1 min (p < 0.0001), 10 min (p < 0.001) and 20 min (p < 0.01). The FC formulated as eye gel was retained on the ocular surface longer than the corresponding eye drop solution. Consequently, the use of the eye gel might extend the interval between instillations and decrease the frequency of administration.
A Comprehensive Review of Boundary Integral Formulations of Acoustic Scattering Problems
Directory of Open Access Journals (Sweden)
S.I. Zaman
2000-12-01
Full Text Available This is a review presenting an overview of the developments in boundary integral formulations of the acoustic scattering problems. Generally, the problem is formulated in one of two ways viz. Green’s representation formula, and the Layer-theoretic formulation utilizing either a simple-layer or a double-layer potential. The review presents and expounds the major contributions in this area over the last four decades. The need for a robust and improved formulation of the exterior scattering problem (Neumann or Dirichlet arose due to the fact that the classical formulation failed to yield a unique solution at (acoustic wave-numbers which correspond to eigenvalues (eigenfrequencies of the corresponding interior scattering problem. Moreover, this correlation becomes more pronounced as the wave-numbers become larger i.e. as the (acoustic frequency increases. The robust integral formulations which are discussed here yield Fredholms integral equations of the second kind which are more amenable to computation than the first kind. However, the integral equation involves a hypersingular kernel which creates ill-conditioning in the final matrix representation. This is circumvented by a regularisation technique. An extensive useful list of references is also presented here for researchers in this area.
Flow Formulation-based Model for the Curriculum-based Course Timetabling Problem
DEFF Research Database (Denmark)
Bagger, Niels-Christian Fink; Kristiansen, Simon; Sørensen, Matias
2015-01-01
problem. This decreases the number of integer variables signicantly and improves the performance compared to the basic formulation. It also shows competitiveness with other approaches based on mixed integer programming from the literature and improves the currently best known lower bound on one data...... instance in the benchmark data set from the second international timetabling competition.......In this work we will present a new mixed integer programming formulation for the curriculum-based course timetabling problem. We show that the model contains an underlying network model by dividing the problem into two models and then connecting the two models back into one model using a maximum ow...
Formulations and algorithms for problems on rock mass and support deformation during mining
Seryakov, VM
2018-03-01
The analysis of problem formulations to calculate stress-strain state of mine support and surrounding rocks mass in rock mechanics shows that such formulations incompletely describe the mechanical features of joint deformation in the rock mass–support system. The present paper proposes an algorithm to take into account the actual conditions of rock mass and support interaction and the algorithm implementation method to ensure efficient calculation of stresses in rocks and support.
A New Formulation for the Combined Maritime Fleet Deployment and Inventory Management Problem
Dong, Bo; Bektas, Tolga; Chandra, Saurabh; Christiansen, Marielle; Fagerholt, Kjetil
2017-01-01
This paper addresses the fleet deployment problem and in particular the treatment of inventory in the maritime case. A new model based on time-continuous formulation for the combined maritime fleet deployment and inventory management problem in Roll-on Roll-off shipping is presented. Tests based on realistic data from the Ro-Ro business show that the model yields good solutions to the combined problem within reasonable time.
A theoretical formulation of the electrophysiological inverse problem on the sphere.
Riera, Jorge J; Valdés, Pedro A; Tanabe, Kunio; Kawashima, Ryuta
2006-04-07
The construction of three-dimensional images of the primary current density (PCD) produced by neuronal activity is a problem of great current interest in the neuroimaging community, though being initially formulated in the 1970s. There exist even now enthusiastic debates about the authenticity of most of the inverse solutions proposed in the literature, in which low resolution electrical tomography (LORETA) is a focus of attention. However, in our opinion, the capabilities and limitations of the electro and magneto encephalographic techniques to determine PCD configurations have not been extensively explored from a theoretical framework, even for simple volume conductor models of the head. In this paper, the electrophysiological inverse problem for the spherical head model is cast in terms of reproducing kernel Hilbert spaces (RKHS) formalism, which allows us to identify the null spaces of the implicated linear integral operators and also to define their representers. The PCD are described in terms of a continuous basis for the RKHS, which explicitly separates the harmonic and non-harmonic components. The RKHS concept permits us to bring LORETA into the scope of the general smoothing splines theory. A particular way of calculating the general smoothing splines is illustrated, avoiding a brute force discretization prematurely. The Bayes information criterion is used to handle dissimilarities in the signal/noise ratios and physical dimensions of the measurement modalities, which could affect the estimation of the amount of smoothness required for that class of inverse solution to be well specified. In order to validate the proposed method, we have estimated the 3D spherical smoothing splines from two data sets: electric potentials obtained from a skull phantom and magnetic fields recorded from subjects performing an experiment of human faces recognition.
Solomon, Keith R; Wilks, Martin F; Bachman, Ammie; Boobis, Alan; Moretto, Angelo; Pastoor, Timothy P; Phillips, Richard; Embry, Michelle R
2016-11-01
When the human health risk assessment/risk management paradigm was developed, it did not explicitly include a "problem formulation" phase. The concept of problem formulation was first introduced in the context of ecological risk assessment (ERA) for the pragmatic reason to constrain and focus ERAs on the key questions. However, this need also exists for human health risk assessment, particularly for cumulative risk assessment (CRA), because of its complexity. CRA encompasses the combined threats to health from exposure via all relevant routes to multiple stressors, including biological, chemical, physical and psychosocial stressors. As part of the HESI Risk Assessment in the 21st Century (RISK21) Project, a framework for CRA was developed in which problem formulation plays a critical role. The focus of this effort is primarily on a chemical CRA (i.e., two or more chemicals) with subsequent consideration of non-chemical stressors, defined as "modulating factors" (ModFs). Problem formulation is a systematic approach that identifies all factors critical to a specific risk assessment and considers the purpose of the assessment, scope and depth of the necessary analysis, analytical approach, available resources and outcomes, and overall risk management goal. There are numerous considerations that are specific to multiple stressors, and proper problem formulation can help to focus a CRA to the key factors in order to optimize resources. As part of the problem formulation, conceptual models for exposures and responses can be developed that address these factors, such as temporal relationships between stressors and consideration of the appropriate ModFs.
International Nuclear Information System (INIS)
Pereira, Luis Carlos Martins
1998-06-01
New Petrov-Galerkin formulations on the finite element methods for convection-diffusion problems with boundary layers are presented. Such formulations are based on a consistent new theory on discontinuous finite element methods. Existence and uniqueness of solutions for these problems in the new finite element spaces are demonstrated. Some numerical experiments shows how the new formulation operate and also their efficacy. (author)
Ogden, F. L.
2017-12-01
HIgh performance computing and the widespread availabilities of geospatial physiographic and forcing datasets have enabled consideration of flood impact predictions with longer lead times and more detailed spatial descriptions. We are now considering multi-hour flash flood forecast lead times at the subdivision level in so-called hydroblind regions away from the National Hydrography network. However, the computational demands of such models are high, necessitating a nested simulation approach. Research on hyper-resolution hydrologic modeling over the past three decades have illustrated some fundamental limits on predictability that are simultaneously related to runoff generation mechanism(s), antecedent conditions, rates and total amounts of precipitation, discretization of the model domain, and complexity or completeness of the model formulation. This latter point is an acknowledgement that in some ways hydrologic understanding in key areas related to land use, land cover, tillage practices, seasonality, and biological effects has some glaring deficiencies. This presentation represents a review of what is known related to the interacting effects of precipitation amount, model spatial discretization, antecedent conditions, physiographic characteristics and model formulation completeness for runoff predictions. These interactions define a region in multidimensional forcing, parameter and process space where there are in some cases clear limits on predictability, and in other cases diminished uncertainty.
FORMULATION OF MATHEMATICAL PROBLEM DESCRIBING PHYSICAL AND CHEMICAL PROCESSES AT CONCRETE CORROSION
Directory of Open Access Journals (Sweden)
Sergey V. Fedosov
2017-06-01
Full Text Available The article deals with the relevance of new scientific research focused on modeling of physical and chemical processes occurring in the cement concrete at their exploitation. The basic types of concrete corrosion are described. The problem of mass transfer processes in a flat reinforced concrete wall at concrete corrosion of the first and the second types has been mathematically formulated.
Photonic Band Structure of Dispersive Metamaterials Formulated as a Hermitian Eigenvalue Problem
Raman, Aaswath; Fan, Shanhui
2010-01-01
We formulate the photonic band structure calculation of any lossless dispersive photonic crystal and optical metamaterial as a Hermitian eigenvalue problem. We further show that the eigenmodes of such lossless systems provide an orthonormal basis, which can be used to rigorously describe the behavior of lossy dispersive systems in general. © 2010 The American Physical Society.
Photonic Band Structure of Dispersive Metamaterials Formulated as a Hermitian Eigenvalue Problem
Raman, Aaswath
2010-02-26
We formulate the photonic band structure calculation of any lossless dispersive photonic crystal and optical metamaterial as a Hermitian eigenvalue problem. We further show that the eigenmodes of such lossless systems provide an orthonormal basis, which can be used to rigorously describe the behavior of lossy dispersive systems in general. © 2010 The American Physical Society.
Performance of mixed formulations for the particle finite element method in soil mechanics problems
Monforte, Lluís; Carbonell, Josep Maria; Arroyo, Marcos; Gens, Antonio
2017-07-01
This paper presents a computational framework for the numerical analysis of fluid-saturated porous media at large strains. The proposal relies, on one hand, on the particle finite element method (PFEM), known for its capability to tackle large deformations and rapid changing boundaries, and, on the other hand, on constitutive descriptions well established in current geotechnical analyses (Darcy's law; Modified Cam Clay; Houlsby hyperelasticity). An important feature of this kind of problem is that incompressibility may arise either from undrained conditions or as a consequence of material behaviour; incompressibility may lead to volumetric locking of the low-order elements that are typically used in PFEM. In this work, two different three-field mixed formulations for the coupled hydromechanical problem are presented, in which either the effective pressure or the Jacobian are considered as nodal variables, in addition to the solid skeleton displacement and water pressure. Additionally, several mixed formulations are described for the simplified single-phase problem due to its formal similitude to the poromechanical case and its relevance in geotechnics, since it may approximate the saturated soil behaviour under undrained conditions. In order to use equal-order interpolants in displacements and scalar fields, stabilization techniques are used in the mass conservation equation of the biphasic medium and in the rest of scalar equations. Finally, all mixed formulations are assessed in some benchmark problems and their performances are compared. It is found that mixed formulations that have the Jacobian as a nodal variable perform better.
Three formulations of the multi-type capacitated facility location problem
DEFF Research Database (Denmark)
Klose, Andreas
The "multi-type" or "modular" capacitated facility location problem is a discrete location model that addresses non-convex piecewise linear production costs as, for instance, staircase cost functions. The literature basically distinguishes three different ways to formulate non-convex piecewise...
Metaheuristics applied to vehicle routing. A case study. Parte 1: formulating the problem
Directory of Open Access Journals (Sweden)
Guillermo González Vargas
2006-09-01
Full Text Available This paper deals with VRP (vehicle routing problem mathematical formulation and presents some methodologies used by different authors to solve VRP variation. This paper is presented as the springboard for introducing future papers about a manufacturing company’s location decisions based on the total distance traveled to distribute its product.
DEFF Research Database (Denmark)
Quaglia, Alberto; Gargalo, Carina L.; Chairakwongsa, Siwanat
2015-01-01
when large problems are considered. In an earlier work, we proposed a computer-aided framework for synthesis and design of process networks. In this contribution, we expand the framework by including methods and tools developed to structure, automate and simplify the mathematical formulation......The developments obtained in recent years in the field of mathematical programming considerably reduced the computational time and resources needed to solve large and complex Mixed Integer Non Linear Programming (MINLP) problems. Nevertheless, the application of these methods in industrial practice...... is still limited by the complexity associated with the mathematical formulation of some problems. In particular, the tasks of design space definition and representation as superstructure, as well as the data collection, validation and handling may become too complex and cumbersome to execute, especially...
Two- and three-index formulations of the minimum cost multicommodity k-splittable flow problem
DEFF Research Database (Denmark)
Gamst, Mette; Jensen, Peter Neergaard; Pisinger, David
2010-01-01
The multicommodity flow problem (MCFP) considers the efficient routing of commodities from their origins to their destinations subject to capacity restrictions and edge costs. Baier et al. [G. Baier, E. Köhler, M. Skutella, On the k-splittable flow problem, in: 10th Annual European Symposium...... of commodities has to be satisfied at the lowest possible cost. The problem has applications in transportation problems where a number of commodities must be routed, using a limited number of distinct transportation units for each commodity. Based on a three-index formulation by Truffot et al. [J. Truffot, C...... on Algorithms, 2002, 101–113] introduced the maximum flow multicommodity k-splittable flow problem (MCkFP) where each commodity may use at most k paths between its origin and its destination. This paper studies the -hard minimum cost multicommodity k-splittable flow problem (MCMCkFP) in which a given flow...
A Mathematical Formulation of the SCOLE Control Problem. Part 2: Optimal Compensator Design
Balakrishnan, A. V.
1988-01-01
The study initiated in Part 1 of this report is concluded and optimal feedback control (compensator) design for stability augmentation is considered, following the mathematical formulation developed in Part 1. Co-located (rate) sensors and (force and moment) actuators are assumed, and allowing for both sensor and actuator noise, stabilization is formulated as a stochastic regulator problem. Specializing the general theory developed by the author, a complete, closed form solution (believed to be new with this report) is obtained, taking advantage of the fact that the inherent structural damping is light. In particular, it is possible to solve in closed form the associated infinite-dimensional steady-state Riccati equations. The SCOLE model involves associated partial differential equations in a single space variable, but the compensator design theory developed is far more general since it is given in the abstract wave equation formulation. The results thus hold for any multibody system so long as the basic model is linear.
Scenario Analysis In The Calculation Of Investment Efficiency–The Problem Of Formulating Assumptions
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Dittmann Iwona
2015-09-01
Full Text Available This article concerns the problem of formulating assumptions in scenario analysis for investments which consist of the renting out of an apartment. The article attempts to indicate the foundations for the formulation of assumptions on the basis of observed retrospective regularities. It includes theoretical considerations regarding scenario design, as well as the results of studies on the formulation, in the past, of quantities which determined or were likely to bring closer estimate the value of the individual explanatory variables for a chosen measure of investment profitability (MIRRFCFE. The dynamics of and correlation between the variables were studied. The research was based on quarterly data from local residential real estate markets in Poland (in the six largest cities in the years 2006 – 2014, as well as on data from the financial market.
Li, Yan; Thomas, Manoj; Osei-Bryson, Kweku-Muata; Levy, Jason
2016-12-15
With the growing popularity of data analytics and data science in the field of environmental risk management, a formalized Knowledge Discovery via Data Analytics (KDDA) process that incorporates all applicable analytical techniques for a specific environmental risk management problem is essential. In this emerging field, there is limited research dealing with the use of decision support to elicit environmental risk management (ERM) objectives and identify analytical goals from ERM decision makers. In this paper, we address problem formulation in the ERM understanding phase of the KDDA process. We build a DM³ ontology to capture ERM objectives and to inference analytical goals and associated analytical techniques. A framework to assist decision making in the problem formulation process is developed. It is shown how the ontology-based knowledge system can provide structured guidance to retrieve relevant knowledge during problem formulation. The importance of not only operationalizing the KDDA approach in a real-world environment but also evaluating the effectiveness of the proposed procedure is emphasized. We demonstrate how ontology inferencing may be used to discover analytical goals and techniques by conceptualizing Hazardous Air Pollutants (HAPs) exposure shifts based on a multilevel analysis of the level of urbanization (and related economic activity) and the degree of Socio-Economic Deprivation (SED) at the local neighborhood level. The HAPs case highlights not only the role of complexity in problem formulation but also the need for integrating data from multiple sources and the importance of employing appropriate KDDA modeling techniques. Challenges and opportunities for KDDA are summarized with an emphasis on environmental risk management and HAPs.
Directory of Open Access Journals (Sweden)
Yan Li
2016-12-01
Full Text Available With the growing popularity of data analytics and data science in the field of environmental risk management, a formalized Knowledge Discovery via Data Analytics (KDDA process that incorporates all applicable analytical techniques for a specific environmental risk management problem is essential. In this emerging field, there is limited research dealing with the use of decision support to elicit environmental risk management (ERM objectives and identify analytical goals from ERM decision makers. In this paper, we address problem formulation in the ERM understanding phase of the KDDA process. We build a DM3 ontology to capture ERM objectives and to inference analytical goals and associated analytical techniques. A framework to assist decision making in the problem formulation process is developed. It is shown how the ontology-based knowledge system can provide structured guidance to retrieve relevant knowledge during problem formulation. The importance of not only operationalizing the KDDA approach in a real-world environment but also evaluating the effectiveness of the proposed procedure is emphasized. We demonstrate how ontology inferencing may be used to discover analytical goals and techniques by conceptualizing Hazardous Air Pollutants (HAPs exposure shifts based on a multilevel analysis of the level of urbanization (and related economic activity and the degree of Socio-Economic Deprivation (SED at the local neighborhood level. The HAPs case highlights not only the role of complexity in problem formulation but also the need for integrating data from multiple sources and the importance of employing appropriate KDDA modeling techniques. Challenges and opportunities for KDDA are summarized with an emphasis on environmental risk management and HAPs.
Li, Yan; Thomas, Manoj; Osei-Bryson, Kweku-Muata; Levy, Jason
2016-01-01
With the growing popularity of data analytics and data science in the field of environmental risk management, a formalized Knowledge Discovery via Data Analytics (KDDA) process that incorporates all applicable analytical techniques for a specific environmental risk management problem is essential. In this emerging field, there is limited research dealing with the use of decision support to elicit environmental risk management (ERM) objectives and identify analytical goals from ERM decision makers. In this paper, we address problem formulation in the ERM understanding phase of the KDDA process. We build a DM3 ontology to capture ERM objectives and to inference analytical goals and associated analytical techniques. A framework to assist decision making in the problem formulation process is developed. It is shown how the ontology-based knowledge system can provide structured guidance to retrieve relevant knowledge during problem formulation. The importance of not only operationalizing the KDDA approach in a real-world environment but also evaluating the effectiveness of the proposed procedure is emphasized. We demonstrate how ontology inferencing may be used to discover analytical goals and techniques by conceptualizing Hazardous Air Pollutants (HAPs) exposure shifts based on a multilevel analysis of the level of urbanization (and related economic activity) and the degree of Socio-Economic Deprivation (SED) at the local neighborhood level. The HAPs case highlights not only the role of complexity in problem formulation but also the need for integrating data from multiple sources and the importance of employing appropriate KDDA modeling techniques. Challenges and opportunities for KDDA are summarized with an emphasis on environmental risk management and HAPs. PMID:27983713
Directory of Open Access Journals (Sweden)
Behrouz Afshar-Nadjafi
2014-01-01
Full Text Available The preemptive Multimode resource investment problem is investigated. The Objective is to minimize the total renewable/nonrenewable resource costs and earliness-tardiness costs by a given project deadline and due dates for activities. In this problem setting preemption is allowed with no setup cost or time. The project contains activities interrelated by finish-start type precedence relations with a time lag of zero, which require a set of renewable and nonrenewable resources. The problem formed in this way is an NP-hard. A mixed integer programming formulation is proposed for the problem and parameters tuned genetic algorithm (GA is proposed to solve it. To evaluate the performance of the proposed algorithm, 120 test problems are used. Comparative statistical results reveal that the proposed GA is efficient and effective in terms of the objective function and computational times.
International Nuclear Information System (INIS)
Guerin, P.
2007-12-01
The neutronic simulation of a nuclear reactor core is performed using the neutron transport equation, and leads to an eigenvalue problem in the steady-state case. Among the deterministic resolution methods, diffusion approximation is often used. For this problem, the MINOS solver based on a mixed dual finite element method has shown his efficiency. In order to take advantage of parallel computers, and to reduce the computing time and the local memory requirement, we propose in this dissertation two domain decomposition methods for the resolution of the mixed dual form of the eigenvalue neutron diffusion problem. The first approach is a component mode synthesis method on overlapping sub-domains. Several Eigenmodes solutions of a local problem solved by MINOS on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second approach is a modified iterative Schwarz algorithm based on non-overlapping domain decomposition with Robin interface conditions. At each iteration, the problem is solved on each sub domain by MINOS with the interface conditions deduced from the solutions on the adjacent sub-domains at the previous iteration. The iterations allow the simultaneous convergence of the domain decomposition and the eigenvalue problem. We demonstrate the accuracy and the efficiency in parallel of these two methods with numerical results for the diffusion model on realistic 2- and 3-dimensional cores. (author)
Jensen, Annie Aarup; Lund, Birthe
2016-01-01
Introduction of a pedagogical concept, Kubus, in a problem oriented learning context--analysed within the framework of an activity system--indicates what might happen when offering tools tempting to influence and regulate students' learning approach and hereby neglecting the importance of existing habits and values. Introduction of this new…
Coping with cannabis in a Caribbean country : from problem formulation to going public
Directory of Open Access Journals (Sweden)
Hymie Rubenstein
1998-07-01
Full Text Available Analyzes the dialectic between problem discovery and formulation, ethical considerations, and the public dissemination of research results. Author describes his personal experience of fieldwork, the moral-ethical dilemmas it involved, and the circulation of research findings on cannabis production and consumption in St. Vincent. He became frustrated that his academic publications were only accessible to a tiny portion of St. Vincent's population and therefore decided to publish about cannabis in the local media.
Kieft, A.C.
2017-01-01
The technological innovation systems (TIS) framework provides a theory to understand under what conditions technological innovations are successfully developed and implemented. The objective of this dissertation is to further strengthen this TIS intervention framework, which is the part of the TIS theoretical framework that facilitates the identification of inhibiting problems and the formulation of interventions. Theoretical adaptations and extensions are proposed and their merits subsequent...
An integer programming formulation of the parsimonious loss of heterozygosity problem.
Catanzaro, Daniele; Labbé, Martine; Halldórsson, Bjarni V
2013-01-01
A loss of heterozygosity (LOH) event occurs when, by the laws of Mendelian inheritance, an individual should be heterozygote at a given site but, due to a deletion polymorphism, is not. Deletions play an important role in human disease and their detection could provide fundamental insights for the development of new diagnostics and treatments. In this paper, we investigate the parsimonious loss of heterozygosity problem (PLOHP), i.e., the problem of partitioning suspected polymorphisms from a set of individuals into a minimum number of deletion areas. Specifically, we generalize Halldórsson et al.'s work by providing a more general formulation of the PLOHP and by showing how one can incorporate different recombination rates and prior knowledge about the locations of deletions. Moreover, we show that the PLOHP can be formulated as a specific version of the clique partition problem in a particular class of graphs called undirected catch-point interval graphs and we prove its general $({\\cal NP})$-hardness. Finally, we provide a state-of-the-art integer programming (IP) formulation and strengthening valid inequalities to exactly solve real instances of the PLOHP containing up to 9,000 individuals and 3,000 SNPs. Our results give perspectives on the mathematics of the PLOHP and suggest new directions on the development of future efficient exact solution approaches.
Global optimization for overall HVAC systems - Part I problem formulation and analysis
International Nuclear Information System (INIS)
Lu Lu; Cai Wenjian; Chai, Y.S.; Xie Lihua
2005-01-01
This paper presents the global optimization technologies for overall heating, ventilating and air conditioning (HVAC) systems. The objective function of global optimization and constraints are formulated based on mathematical models of the major components. All these models are associated with power consumption components and heat exchangers for transferring cooling load. The characteristics of all the major components are briefly introduced by models, and the interactions between them are analyzed and discussed to show the complications of the problem. According to the characteristics of the operating components, the complicated original optimization problem for overall HVAC systems is transformed and simplified into a compact form ready for optimization
A new formulation for the 2-echelon capacitated vehicle routing problem
DEFF Research Database (Denmark)
Jepsen, Mads Kehlet; Røpke, Stefan; Spoorendonk, Simon
The 2-echelon capacitated vehicle routing problem (2E-CVRP) is a transportation and distribution problem where goods are transported from a depot to a set of customers possible via optional satellite facilities. The 2E-CVRP is relevant in city-logistic applications where legal restrictions make...... it infeasible to use large trucks within the center of large cities. We propose a new mathematical formulation for the 2E-CVRP with much fewer variables than the previously proposed but with several constraint sets of exponential size. The strength of the model is implied by the facts that many cutting planes...
SEACAS Theory Manuals: Part 1. Problem Formulation in Nonlinear Solid Mechancis
Energy Technology Data Exchange (ETDEWEB)
Attaway, S.W.; Laursen, T.A.; Zadoks, R.I.
1998-08-01
This report gives an introduction to the basic concepts and principles involved in the formulation of nonlinear problems in solid mechanics. By way of motivation, the discussion begins with a survey of some of the important sources of nonlinearity in solid mechanics applications, using wherever possible simple one dimensional idealizations to demonstrate the physical concepts. This discussion is then generalized by presenting generic statements of initial/boundary value problems in solid mechanics, using linear elasticity as a template and encompassing such ideas as strong and weak forms of boundary value problems, boundary and initial conditions, and dynamic and quasistatic idealizations. The notational framework used for the linearized problem is then extended to account for finite deformation of possibly inelastic solids, providing the context for the descriptions of nonlinear continuum mechanics, constitutive modeling, and finite element technology given in three companion reports.
A Simple FEM Formulation Applied to Nonlinear Problems of Impact with Thermomechanical Coupling
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João Paulo de Barros Cavalcante
Full Text Available Abstract The thermal effects of problems involving deformable structures are essential to describe the behavior of materials in feasible terms. Verifying the transformation of mechanical energy into heat it is possible to predict the modifications of mechanical properties of materials due to its temperature changes. The current paper presents the numerical development of a finite element method suitable for nonlinear structures coupled with thermomechanical behavior; including impact problems. A simple and effective alternative formulation is presented, called FEM positional, to deal with the dynamic nonlinear systems. The developed numerical is based on the minimum potential energy written in terms of nodal positions instead of displacements. The effects of geometrical, material and thermal nonlinearities are considered. The thermodynamically consistent formulation is based on the laws of thermodynamics and the Helmholtz free-energy, used to describe the thermoelastic and the thermoplastic behaviors. The coupled thermomechanical model can result in secondary effects that cause redistributions of internal efforts, depending on the history of deformation and material properties. The numerical results of the proposed formulation are compared with examples found in the literature.
Fall, Mandiaye; Boutami, Salim; Glière, Alain; Stout, Brian; Hazart, Jerome
2013-06-01
A combination of the multilevel fast multipole method (MLFMM) and boundary element method (BEM) can solve large scale photonics problems of arbitrary geometry. Here, MLFMM-BEM algorithm based on a scalar and vector potential formulation, instead of the more conventional electric and magnetic field formulations, is described. The method can deal with multiple lossy or lossless dielectric objects of arbitrary geometry, be they nested, in contact, or dispersed. Several examples are used to demonstrate that this method is able to efficiently handle 3D photonic scatterers involving large numbers of unknowns. Absorption, scattering, and extinction efficiencies of gold nanoparticle spheres, calculated by the MLFMM, are compared with Mie's theory. MLFMM calculations of the bistatic radar cross section (RCS) of a gold sphere near the plasmon resonance and of a silica coated gold sphere are also compared with Mie theory predictions. Finally, the bistatic RCS of a nanoparticle gold-silver heterodimer calculated with MLFMM is compared with unmodified BEM calculations.
Pietrabissa, Antonio
2011-12-01
The admission control problem can be modelled as a Markov decision process (MDP) under the average cost criterion and formulated as a linear programming (LP) problem. The LP formulation is attractive in the present and future communication networks, which support an increasing number of classes of service, since it can be used to explicitly control class-level requirements, such as class blocking probabilities. On the other hand, the LP formulation suffers from scalability problems as the number C of classes increases. This article proposes a new LP formulation, which, even if it does not introduce any approximation, is much more scalable: the problem size reduction with respect to the standard LP formulation is O((C + 1)2/2 C ). Theoretical and numerical simulation results prove the effectiveness of the proposed approach.
Two-point boundary value and Cauchy formulations in an axisymmetrical MHD equilibrium problem
International Nuclear Information System (INIS)
Atanasiu, C.V.; Subbotin, A.A.
1999-01-01
In this paper we present two equilibrium solvers for axisymmetrical toroidal configurations, both based on the expansion in poloidal angle method. The first one has been conceived as a two-point boundary value solver in a system of coordinates with straight field lines, while the second one uses a well-conditioned Cauchy formulation of the problem in a general curvilinear coordinate system. In order to check the capability of our moment methods to describe equilibrium accurately, a comparison of the moment solutions with analytical solutions obtained for a Solov'ev equilibrium has been performed. (author)
International Nuclear Information System (INIS)
Mugge, J.W.
1979-10-01
The collisional plasma transport problem is formulated as an initial boundary value problem for general characteristic boundary conditions. Starting from the full set of hydrodynamic and electrodynamic equations an expansion in the electron-ion mass ratio together with a multiple timescale method yields simplified equations on each timescale. On timescales where many collisions have taken place for the simplified equations the initial boundary value problem is formulated. Through the introduction of potentials a two-dimensional scalar formulation in terms of quasi-linear integro-differential equations of second order for a domain consisting of plasma and vacuum sub-domains is obtained. (Auth.)
A game-theoretic formulation of the homogeneous self-reconfiguration problem
Pickem, Daniel
2015-12-15
In this paper we formulate the homogeneous two- and three-dimensional self-reconfiguration problem over discrete grids as a constrained potential game. We develop a game-theoretic learning algorithm based on the Metropolis-Hastings algorithm that solves the self-reconfiguration problem in a globally optimal fashion. Both a centralized and a fully decentralized algorithm are presented and we show that the only stochastically stable state is the potential function maximizer, i.e. the desired target configuration. These algorithms compute transition probabilities in such a way that even though each agent acts in a self-interested way, the overall collective goal of self-reconfiguration is achieved. Simulation results confirm the feasibility of our approach and show convergence to desired target configurations.
A game-theoretic formulation of the homogeneous self-reconfiguration problem
Pickem, Daniel; Egerstedt, Magnus; Shamma, Jeff S.
2015-01-01
In this paper we formulate the homogeneous two- and three-dimensional self-reconfiguration problem over discrete grids as a constrained potential game. We develop a game-theoretic learning algorithm based on the Metropolis-Hastings algorithm that solves the self-reconfiguration problem in a globally optimal fashion. Both a centralized and a fully decentralized algorithm are presented and we show that the only stochastically stable state is the potential function maximizer, i.e. the desired target configuration. These algorithms compute transition probabilities in such a way that even though each agent acts in a self-interested way, the overall collective goal of self-reconfiguration is achieved. Simulation results confirm the feasibility of our approach and show convergence to desired target configurations.
Splitting method for the combined formulation of fluid-particle problem
International Nuclear Information System (INIS)
Choi, Hyung Gwon; Yoo, Jung Yul; Joseph, D. D.
2000-01-01
A splitting method for the direct numerical simulation of solid-liquid mixtures is presented, where a symmetric pressure equation is newly proposed. Through numerical experiment, it is found that the newly proposed splitting method works well with a matrix-free formulation for some bench mark problems avoiding an erroneous pressure field which appears when using the conventional pressure equation of a splitting method. When deriving a typical pressure equation of a splitting method, the motion of a solid particle has to be approximated by the 'intermediate velocity' instead of treating it as unknowns since it is necessary as a boundary condition. Therefore, the motion of a solid particle is treated in such an explicit way that a particle moves by the known form drag(pressure drag) that is calculated from the pressure equation in the previous step. From the numerical experiment, it was shown that this method gives an erroneous pressure field even for the very small time step size as a particle velocity increases. In this paper, coupling the unknowns of particle velocities in the pressure equation is proposed, where the resulting matrix is reduced to the symmetric one by applying the projector of the combined formulation. It has been tested over some bench mark problems and gives reasonable pressure fields
Waseda, Katsuhisa; Ako, Junya; Yamasaki, Masao; Koizumi, Tomomi; Sakurai, Ryota; Hongo, Yoichiro; Koo, Bon-Kwon; Ormiston, John; Worthley, Stephen G; Whitbourn, Robert J; Walters, Darren L; Meredith, Ian T; Fitzgerald, Peter J; Honda, Yasuhiro
2011-06-01
Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers. Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound-detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; Ppolymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents. The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.
Eddy current imaging. Simplifying the direct problem. Analysis of a 2D case with formulations
International Nuclear Information System (INIS)
Spineanu, A.; Zorgati, R.
1995-01-01
Eddy current non-destructive testing is used by EDF to detect faults affecting conductive objects such as steam generator tubes. A new technique, known as eddy current imaging, is being developed to facilitate diagnosis in this context. The first stage in this work, discussed in the present paper, consists in solving the direct problem. This entails determining the measurable quantities, on the basis of a thorough knowledge of the material considered. This was done by formulating the direct problem in terms of eddy currents in general 3D geometry context, applying distribution theory and Maxwell equations. Since no direct problem code was available we resorted to simplified situations. Taking care not to interfere with previous developments or those to be attempted in an inversion context, we studied the case of a flaw affecting a 2D structure, illuminated by a plane wave type probe. For this configuration, we studied the exact model and compared results with those of a linearized simplified model. This study emphasizes the ill-posed situation of the eddy current inverse problem related with the severe electromagnetic field attenuation. This means that regularization of the inverse problem, although absolutely necessary, will not be sufficient. Owing to the simplicity of the models available and implemented during the inversion process, processing real data would not yet be possible. We must first focus all our efforts on the direct 3 D problem, in conformity with the requirements of the inverse procedure ad describing a realistic eddy current NDT situation. At the same time, consideration should be given to the design of a specific probe customized for eddy current imaging. (authors). 9 refs., 5 figs., 3 appends
Main formulations of the finite element method for the problems of structural mechanics. Part 2
Directory of Open Access Journals (Sweden)
Ignat’ev Aleksandr Vladimirovich
Full Text Available The author offers a classification of Finite Element formulations, which allows orienting in a great number of the published and continuing to be published works on the problem of raising the efficiency of this widespread numerical method. The second part of the article offers examination of straight formulations of FEM in the form of displacement approach, area method and classical mixed-mode method. The question of solution convergence according to FEM in the form of classical mixed-mode method is considered on the example of single-input single-output system of a beam in case of finite element grid refinement. The author draws a conclusion, that extinction of algebraic equations system of FEM in case of passage to the limit is not a peculiar feature of this method in general, but manifests itself only in some particular cases. At the same time the obtained results prove that FEM in mixed-mode form provides obtaining more stable results in case of finite element grid refinement in comparison with FEM in the form of displacement approach. It is quite obvious that the same qualities will appear also in two-dimensional systems.
Main formulations of the finite element method for the problems of structural mechanics. Part 3
Directory of Open Access Journals (Sweden)
Ignat’ev Aleksandr Vladimirovich
2015-01-01
Full Text Available In this paper the author offers is the classification of the formulae of Finite Element Method. This classification help to orient in a huge number of published articles, as well as those to be published, which are dedicated to the problem of enhancing the efficiency of the most commonly used method. The third part of the article considers the variation formulations of FEM and the energy principles lying in the basis of it. If compared to the direct method, which is applied only to finite elements of a simple geometrical type, the variation formulations of FEM are applicable to the elements of any type. All the variation methods can be conventionally divided into two groups. The methods of the first group are based on the principle of energy functional stationarity - a potential system energy, additional energy or on the basis of these energies, which means the full energy. The methods of the second group are based on the variants of mathematical methods of weighted residuals for solving the differential equations, which in some cases can be handled according to the principle of possible displacements or extreme energy principles. The most widely used and multipurpose is the approach based on the use of energy principles coming from the energy conservation law: principle of possible changes in stress state, principle of possible change in stress-strain state.
Energy Technology Data Exchange (ETDEWEB)
Souza Filho, Erito M.; Bahiense, Laura; Ferreira Filho, Virgilio J.M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Lima, Leonardo [Centro Federal de Educacao Tecnologica Celso Sukow da Fonseca (CEFET-RJ), Rio de Janeiro, RJ (Brazil)
2008-07-01
Pipeline are known as the most reliable and economical mode of transportation for petroleum and its derivatives, especially when large amounts of products have to be pumped for large distances. In this work we address the short-term schedule of a pipeline system comprising the distribution of several petroleum derivatives from a single oil refinery to several depots, connected to local consumer markets, through a single multi-product pipeline. We propose an integer linear programming formulation and a variable neighborhood search meta-heuristic in order to compare the performances of the exact and heuristic approaches to the problem. Computational tests in C language and MOSEL/XPRESS-MP language are performed over a real Brazilian pipeline system. (author)
Optimal Water-Power Flow Problem: Formulation and Distributed Optimal Solution
Energy Technology Data Exchange (ETDEWEB)
Dall-Anese, Emiliano [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhao, Changhong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zamzam, Admed S. [University of Minnesota; Sidiropoulos, Nicholas D. [University of Minnesota; Taylor, Josh A. [University of Toronto
2018-01-12
This paper formalizes an optimal water-power flow (OWPF) problem to optimize the use of controllable assets across power and water systems while accounting for the couplings between the two infrastructures. Tanks and pumps are optimally managed to satisfy water demand while improving power grid operations; {for the power network, an AC optimal power flow formulation is augmented to accommodate the controllability of water pumps.} Unfortunately, the physics governing the operation of the two infrastructures and coupling constraints lead to a nonconvex (and, in fact, NP-hard) problem; however, after reformulating OWPF as a nonconvex, quadratically-constrained quadratic problem, a feasible point pursuit-successive convex approximation approach is used to identify feasible and optimal solutions. In addition, a distributed solver based on the alternating direction method of multipliers enables water and power operators to pursue individual objectives while respecting the couplings between the two networks. The merits of the proposed approach are demonstrated for the case of a distribution feeder coupled with a municipal water distribution network.
Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging
International Nuclear Information System (INIS)
Yao Dezhong; He Bin
2003-01-01
In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping
Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging
Energy Technology Data Exchange (ETDEWEB)
Yao Dezhong [School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu City, 610054, Sichuan Province (China); He Bin [The University of Illinois at Chicago, IL (United States)
2003-11-07
In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping.
Guerrero, José Luis Morales; Vidal, Manuel Cánovas; Nicolás, José Andrés Moreno; López, Francisco Alhama
2018-05-01
New additional conditions required for the uniqueness of the 2D elastostatic problems formulated in terms of potential functions for the derived Papkovich-Neuber representations, are studied. Two cases are considered, each of them formulated by the scalar potential function plus one of the rectangular non-zero components of the vector potential function. For these formulations, in addition to the original (physical) boundary conditions, two new additional conditions are required. In addition, for the complete Papkovich-Neuber formulation, expressed by the scalar potential plus two components of the vector potential, the additional conditions established previously for the three-dimensional case in z-convex domain can be applied. To show the usefulness of these new conditions in a numerical scheme two applications are numerically solved by the network method for the three cases of potential formulations.
An MPCC Formulation and Its Smooth Solution Algorithm for Continuous Network Design Problem
Directory of Open Access Journals (Sweden)
Guangmin Wang
2017-12-01
Full Text Available Continuous network design problem (CNDP is searching for a transportation network configuration to minimize the sum of the total system travel time and the investment cost of link capacity expansions by considering that the travellers follow a traditional Wardrop user equilibrium (UE to choose their routes. In this paper, the CNDP model can be formulated as mathematical programs with complementarity constraints (MPCC by describing UE as a non-linear complementarity problem (NCP. To address the difficulty resulting from complementarity constraints in MPCC, they are substituted by the Fischer-Burmeister (FB function, which can be smoothed by the introduction of the smoothing parameter. Therefore, the MPCC can be transformed into a well-behaved non-linear program (NLP by replacing the complementarity constraints with a smooth equation. Consequently, the solver such as LINDOGLOBAL in GAMS can be used to solve the smooth approximate NLP to obtain the solution to MPCC for modelling CNDP. The numerical experiments on the example from the literature demonstrate that the proposed algorithm is feasible.
Quinn, J. D.; Reed, P. M.; Giuliani, M.; Castelletti, A.
2017-08-01
Managing water resources systems requires coordinated operation of system infrastructure to mitigate the impacts of hydrologic extremes while balancing conflicting multisectoral demands. Traditionally, recommended management strategies are derived by optimizing system operations under a single problem framing that is assumed to accurately represent the system objectives, tacitly ignoring the myriad of effects that could arise from simplifications and mathematical assumptions made when formulating the problem. This study illustrates the benefits of a rival framings framework in which analysts instead interrogate multiple competing hypotheses of how complex water management problems should be formulated. Analyzing rival framings helps discover unintended consequences resulting from inherent biases of alternative problem formulations. We illustrate this on the monsoonal Red River basin in Vietnam by optimizing operations of the system's four largest reservoirs under several different multiobjective problem framings. In each rival framing, we specify different quantitative representations of the system's objectives related to hydropower production, agricultural water supply, and flood protection of the capital city of Hanoi. We find that some formulations result in counterintuitive behavior. In particular, policies designed to minimize expected flood damages inadvertently increase the risk of catastrophic flood events in favor of hydropower production, while min-max objectives commonly used in robust optimization provide poor representations of system tradeoffs due to their instability. This study highlights the importance of carefully formulating and evaluating alternative mathematical abstractions of stakeholder objectives describing the multisectoral water demands and risks associated with hydrologic extremes.
Obesity and internalized weight stigma: a formulation model for an emerging psychological problem.
Ratcliffe, Denise; Ellison, Nell
2015-03-01
Obese individuals frequently experience weight stigma and this is associated with psychological distress and difficulties. The process of external devaluation can lead to negative self-perception and evaluation and some obese individuals develop "internalized weight stigma". The prevalence of weight stigma is well established but there is a lack of information about the interplay between external and internal weight stigma. To synthesize the literature on the psychological effects of weight stigma into a formulation model that addresses the maintenance of internalized weight stigma. Current research on the psychological impact of weight stigma was reviewed. We identify cognitive, behavioural and attentional processes that maintain psychological conditions where self-evaluation plays a central role. A model was developed based on clinical utility. The model focuses on identifying factors that influence and maintain internalized weight stigma. We highlight the impact of negative societal and interpersonal experiences of weight stigma on how individuals view themselves as an obese person. Processing the self as a stigmatized individual is at the core of the model. Maintenance factors include negative self-judgements about the meaning of being an obese individual, attentional and mood shifts, and avoidance and safety behaviours. In addition, eating and weight management behaviours become deregulated and maintain both obesity and weight stigma. As obesity increases, weight stigma and the associated psychological effects are likely to increase. We provide a framework for formulating and intervening with internalized weight stigma as well as making therapists aware of the applicability and transferability of strategies that they may already use with other presenting problems.
Fraser, Suzanne; Moore, David
2011-11-01
Producing and implementing credible and effective policies on illicit drug use is generally seen as an important aspect of health governance in the West. Yet the controversy surrounding illicit drug use means this is no easy task. With public opinion perceived by policy makers to be set against illicit drug use, and understandings of its effects tending towards generalisation and pathologisation, the need for timely and rational responses is considered self evident. These responses are, however, regularly criticised as driven as much by electoral politics and expedience as by research findings or expert opinion. Destined to receive close critical scrutiny from all sides, these policies, and the processes undertaken to develop them, are obliged to negotiate a complex political domain. Despite this scrutiny, and the pressure it brings to bear on the policy-making process, little scholarly attention has been paid to the area to date. In this article, we examine in detail one important area of illicit drug policy - the use of amphetamine-type stimulants (ATS) in Australia. We draw on the international critical literature on the ATS problem to situate our analysis. We note that ideas of 'panic', including Cohen's notion of moral panic, have been used here to good effect, but, aiming to acknowledge the complexities of policy, we turn to poststructuralist methods of policy analysis to pursue a different approach. Following Bacchi's observation that 'we are governed through problematisations rather than policies' (2009, p. xi), we ask how the problem of ATS use has been formulated in policy. We examine key state and national policy documents, and two central themes found in them - causation and evidence - to identify the specific strategies used to authorise the recommendations and measures presented as following from the problem of ATS use. In doing so, we clarify important ways in which policy may at times work to obscure the limits of its legitimacy. Copyright © 2011
Ioele, Giuseppina; De Luca, Michele; Dinç, Erdal; Oliverio, Filomena; Ragno, Gaetano
2011-01-01
A chemometric approach based on the combined use of the principal component analysis (PCA) and artificial neural network (ANN) was developed for the multicomponent determination of caffeine (CAF), mepyramine (MEP), phenylpropanolamine (PPA) and pheniramine (PNA) in their pharmaceutical preparations without any chemical separation. The predictive ability of the ANN method was compared with the classical linear regression method Partial Least Squares 2 (PLS2). The UV spectral data between 220 and 300 nm of a training set of sixteen quaternary mixtures were processed by PCA to reduce the dimensions of input data and eliminate the noise coming from instrumentation. Several spectral ranges and different numbers of principal components (PCs) were tested to find the PCA-ANN and PLS2 models reaching the best determination results. A two layer ANN, using the first four PCs, was used with log-sigmoid transfer function in first hidden layer and linear transfer function in output layer. Standard error of prediction (SEP) was adopted to assess the predictive accuracy of the models when subjected to external validation. PCA-ANN showed better prediction ability in the determination of PPA and PNA in synthetic samples with added excipients and pharmaceutical formulations. Since both components are characterized by low absorptivity, the better performance of PCA-ANN was ascribed to the ability in considering all non-linear information from noise or interfering excipients.
Clarification process: Resolution of decision-problem conditions
Dieterly, D. L.
1980-01-01
A model of a general process which occurs in both decisionmaking and problem-solving tasks is presented. It is called the clarification model and is highly dependent on information flow. The model addresses the possible constraints of individual indifferences and experience in achieving success in resolving decision-problem conditions. As indicated, the application of the clarification process model is only necessary for certain classes of the basic decision-problem condition. With less complex decision problem conditions, certain phases of the model may be omitted. The model may be applied across a wide range of decision problem conditions. The model consists of two major components: (1) the five-phase prescriptive sequence (based on previous approaches to both concepts) and (2) the information manipulation function (which draws upon current ideas in the areas of information processing, computer programming, memory, and thinking). The two components are linked together to provide a structure that assists in understanding the process of resolving problems and making decisions.
International Nuclear Information System (INIS)
Kunz, Matthew W.; Mouschovias, Telemachos Ch.
2009-01-01
We formulate the problem of the formation and subsequent evolution of fragments (or cores) in magnetically supported, self-gravitating molecular clouds in two spatial dimensions. The six-fluid (neutrals, electrons, molecular and atomic ions, positively charged, negatively charged, and neutral grains) physical system is governed by the radiation, nonideal magnetohydrodynamic equations. The magnetic flux is not assumed to be frozen in any of the charged species. Its evolution is determined by a newly derived generalized Ohm's law, which accounts for the contributions of both elastic and inelastic collisions to ambipolar diffusion and Ohmic dissipation. The species abundances are calculated using an extensive chemical-equilibrium network. Both MRN and uniform grain size distributions are considered. The thermal evolution of the protostellar core and its effect on the dynamics are followed by employing the gray flux-limited diffusion approximation. Realistic temperature-dependent grain opacities are used that account for a variety of grain compositions. We have augmented the publicly available Zeus-MP code to take into consideration all these effects and have modified several of its algorithms to improve convergence, accuracy, and efficiency. Results of magnetic star formation simulations that accurately track the evolution of a protostellar fragment from a density ≅10 3 cm -3 to a density ≅10 15 cm -3 , while rigorously accounting for both nonideal MHD processes and radiative transfer, are presented in a separate paper.
Formulation and solution of the classical seashell problem. Pt. 1. Seashell geometry
Energy Technology Data Exchange (ETDEWEB)
Illert, C.
1987-07-01
Despite an extensive scholarly literature dating back to classical times, seashell geometries have hitherto resisted rigorous theoretical analysis, leaving applied scientists to adopt a directionless empirical approach toward classification. The voluminousness of recent palaeontological literature demonstrates the importance of this problem to applied scientists, but in no way reflects corresponding conceptual or theoretical advances beyond the XIX century thinking which was so ably summarized by Sir D'Arcy Wentworth Thompson in 1917. However, in this foundation paper for the newly emerging science of theoretical conchology, unifying theoretical considerations for the first time, permits a rigorous formulation and a complete solution of the problem of biological shell geometries. Shell coiling about the axis of symmetry can be deduced from first principles using energy considerations associated with incremental growth. The present paper shows that those shell apertures which are incurved ('cowrielike'), outflared ('stromblike') or even backturned ('opisthostomoidal') are merely special cases of a much broader spectrum of 'allowable' energy-efficient growth trajectories (tensile elastic clockspring spirals), many of which were widely used by Cretaceous ammonites. Energy considerations also dictate shell growth along the axis of symmetry, thus seashell spires can be understood in terms of certain special figures of revolution (Moebius elastic conoids), the better-known coeloconoidal and cyrtoconoidal shell spires being only two special cases arising from a whole class of topologically possible, energy efficient and biologically observed geometries. The 'wires' and 'conoids' of the present paper are instructive conceptual simplifications sufficient for present purposes. A second paper will later deal with generalized tubular surfaces in three dimensions.
General Relativity without paradigm of space-time covariance, and resolution of the problem of time
Soo, Chopin; Yu, Hoi-Lai
2014-01-01
The framework of a theory of gravity from the quantum to the classical regime is presented. The paradigm shift from full space-time covariance to spatial diffeomorphism invariance, together with clean decomposition of the canonical structure, yield transparent physical dynamics and a resolution of the problem of time. The deep divide between quantum mechanics and conventional canonical formulations of quantum gravity is overcome with a Schrödinger equation for quantum geometrodynamics that describes evolution in intrinsic time. Unitary time development with gauge-invariant temporal ordering is also viable. All Kuchar observables become physical; and classical space-time, with direct correlation between its proper times and intrinsic time intervals, emerges from constructive interference. The framework not only yields a physical Hamiltonian for Einstein's theory, but also prompts natural extensions and improvements towards a well behaved quantum theory of gravity. It is a consistent canonical scheme to discuss Horava-Lifshitz theories with intrinsic time evolution, and of the many possible alternatives that respect 3-covariance (rather than the more restrictive 4-covariance of Einstein's theory), Horava's "detailed balance" form of the Hamiltonian constraint is essentially pinned down by this framework. Issues in quantum gravity that depend on radiative corrections and the rigorous definition and regularization of the Hamiltonian operator are not addressed in this work.
CSIR Research Space (South Africa)
Fedotov, I
2006-07-01
Full Text Available The Combined Helmholtz Integral Equation – Fourier series Formulation (CHIEFF) is based on representation of a velocity potential in terms of Fourier series and finding the Fourier coefficients of this expansion. The solution could be substantially...
Directory of Open Access Journals (Sweden)
V. S. Zarubin
2016-01-01
in its plane, and in the circular cylinder unlimited in length.An approximate numerical solution of the differential equation that is included in a nonlinear mathematical model of the thermal explosion enables us to obtain quantitative estimates of combination of determining parameters at which the limit state occurs in areas of not only canonical form. A capability to study of the thermal explosion state can be extended in the context of development of mathematical modeling methods, including methods of model analysis to describe the thermal state of solids.To analyse a mathematical model of the thermal explosion in a homogeneous solid the paper uses a variational approach based on the dual variational formulation of the appropriate nonlinear stationary problem of heat conduction in such a body. This formulation contains two alternative functional reaching the matching values in their stationary points corresponding to the true temperature distribution. This functional feature allows you to not only get an approximate quantitative estimate of the combination of parameters that determine the thermal explosion state, but also to find the greatest possible error in such estimation.
Directory of Open Access Journals (Sweden)
Koh Kim Jie
2017-01-01
Full Text Available Quadratic damping nonlinearity is challenging for displacement based structural dynamics problem as the problem is nonlinear in time derivative of the primitive variable. For such nonlinearity, the formulation of tangent stiffness matrix is not lucid in the literature. Consequently, ambiguity related to kinematics update arises when implementing the time integration-iterative algorithm. In present work, an Euler-Bernoulli beam vibration problem with quadratic damping nonlinearity is addressed as the main source of quadratic damping nonlinearity arises from drag force estimation, which is generally valid only for slender structures. Employing Newton-Raphson formulation, tangent stiffness components associated with quadratic damping nonlinearity requires velocity input for evaluation purpose. For this reason, two mathematically equivalent algorithm structures with different kinematics arrangement are tested. Both algorithm structures result in the same accuracy and convergence characteristic of solution.
Towards the resolution of the solar neutrino problem
Energy Technology Data Exchange (ETDEWEB)
Friedland, Alexander [Univ. of California, Berkeley, CA (United States)
2000-08-01
A number of experiments have accumulated over the years a large amount of solar neutrino data. The data indicate that the observed solar neutrino flux is significantly smaller than expected and, furthermore, that the electron neutrino survival probability is energy dependent. This ''solar neutrino problem'' is best solved by assuming that the electron neutrino oscillates into another neutrino species. Even though one can classify the solar neutrino deficit as strong evidence for neutrino oscillations, it is not yet considered a definitive proof. Traditional objections are that the evidence for solar neutrino oscillations relies on a combination of hard, different experiments, and that the Standard Solar Model (SSM) might not be accurate enough to precisely predict the fluxes of different solar neutrino components. Even though it seems unlikely that modifications to the SSM alone can explain the current solar neutrino data, one still cannot completely discount the possibility that a combination of unknown systematic errors in some of the experiments and certain modifications to the SSM could conspire to yield the observed data. To conclusively demonstrate that there is indeed new physics in solar neutrinos, new experiments are aiming at detecting ''smoking gun'' signatures of neutrino oscillations, such as an anomalous seasonal variation in the observed neutrino flux or a day-night variation due to the regeneration of electron neutrinos in the Earth. In this dissertation we study the sensitivity reach of two upcoming neutrino experiments, Borexino and KamLAND, to both of these effects. Results of neutrino oscillation experiments for the case of two-flavor oscillations have always been presented on the (sin^{2} 2θ, Δm^{2}) parameter space. We point out, however, that this parameterization misses the half of the parameter space π/4 < θ < π/2, which is physically inequivalent to the region 0 < θ < π/4 in
Energy Technology Data Exchange (ETDEWEB)
Guerin, P
2007-12-15
The neutronic simulation of a nuclear reactor core is performed using the neutron transport equation, and leads to an eigenvalue problem in the steady-state case. Among the deterministic resolution methods, diffusion approximation is often used. For this problem, the MINOS solver based on a mixed dual finite element method has shown his efficiency. In order to take advantage of parallel computers, and to reduce the computing time and the local memory requirement, we propose in this dissertation two domain decomposition methods for the resolution of the mixed dual form of the eigenvalue neutron diffusion problem. The first approach is a component mode synthesis method on overlapping sub-domains. Several Eigenmodes solutions of a local problem solved by MINOS on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second approach is a modified iterative Schwarz algorithm based on non-overlapping domain decomposition with Robin interface conditions. At each iteration, the problem is solved on each sub domain by MINOS with the interface conditions deduced from the solutions on the adjacent sub-domains at the previous iteration. The iterations allow the simultaneous convergence of the domain decomposition and the eigenvalue problem. We demonstrate the accuracy and the efficiency in parallel of these two methods with numerical results for the diffusion model on realistic 2- and 3-dimensional cores. (author)
A general real-time formulation for multi-rate mass transfer problems
Directory of Open Access Journals (Sweden)
O. Silva
2009-08-01
Full Text Available Many flow and transport phenomena, ranging from delayed storage in pumping tests to tailing in river or aquifer tracer breakthrough curves or slow kinetics in reactive transport, display non-equilibrium (NE behavior. These phenomena are usually modeled by non-local in time formulations, such as multi-porosity, multiple processes non equilibrium, continuous time random walk, memory functions, integro-differential equations, fractional derivatives or multi-rate mass transfer (MRMT, among others. We present a MRMT formulation that can be used to represent all these models of non equilibrium. The formulation can be extended to non-linear phenomena. Here, we develop an algorithm for linear mass transfer, which is accurate, computationally inexpensive and easy to implement in existing groundwater or river flow and transport codes. We illustrate this approach by application to published data involving NE groundwater flow and solute transport in rivers and aquifers.
From a Nonlinear, Nonconvex Variational Problem to a Linear, Convex Formulation
International Nuclear Information System (INIS)
Egozcue, J.; Meziat, R.; Pedregal, P.
2002-01-01
We propose a general approach to deal with nonlinear, nonconvex variational problems based on a reformulation of the problem resulting in an optimization problem with linear cost functional and convex constraints. As a first step we explicitly explore these ideas to some one-dimensional variational problems and obtain specific conclusions of an analytical and numerical nature
Tangwa, G B
2004-02-01
In this paper, the author attempts to explore some of the problems connected with the formulation and application of international biomedical ethical guidelines, with particular reference to Africa. Recent attempts at revising and updating some international medical ethical guidelines have been bedevilled by intractable controversies and wrangling regarding both the content and formulation. From the vantage position of relative familiarity with both African and Western contexts, and the privilege of having been involved in the revision and updating of one of the international ethical guidelines, the author reflects broadly on these issues and attempts prescribing an approach from both the theoretical and practical angles liable to mitigate, if not completely eliminate, some of the problems and difficulties.
DEFF Research Database (Denmark)
Uchoa, Eduardo; Fukasawa, Ricardo; Lysgaard, Jens
This paper presents a robust branch-cut-and-price algorithm for the Capacitated Minimum Spanning Tree Problem (CMST). The variables are associated to q-arbs, a structure that arises from a relaxation of the capacitated prize-collecting arborescence problem in order to make it solvable in pseudo......-polynomial time. Traditional inequalities over the arc formulation, like Capacity Cuts, are also used. Moreover, a novel feature is introduced in such kind of algorithms. Powerful new cuts expressed over a very large set of variables could be added, without increasing the complexity of the pricing subproblem...
A formulation to analyze system-of-systems problems: A case study of airport metroplex operations
Ayyalasomayajula, Sricharan Kishore
A system-of-systems (SoS) can be described as a collection of multiple, heterogeneous, distributed, independent components interacting to achieve a range of objectives. A generic formulation was developed to model component interactions in an SoS to understand their influence on overall SoS performance. The formulation employs a lexicon to aggregate components into hierarchical interaction networks and understand how their topological properties affect the performance of the aggregations. Overall SoS performance is evaluated by monitoring the changes in stakeholder profitability due to changes in component interactions. The formulation was applied to a case study in air transportation focusing on operations at airport metroplexes. Metroplexes are geographical regions with two or more airports in close proximity to one another. The case study explored how metroplex airports interact with one another, what dependencies drive these interactions, and how these dependencies affect metroplex throughput and capacity. Metrics were developed to quantify runway dependencies at a metroplex and were correlated with its throughput and capacity. Operations at the New York/New Jersey metroplex (NYNJ) airports were simulated to explore the feasibility of operating very large aircraft (VLA), such as the Airbus A380, as a delay-mitigation strategy at these airports. The proposed formulation was employed to analyze the impact of this strategy on different stakeholders in the national air transportation system (ATS), such as airlines and airports. The analysis results and their implications were used to compare the pros and cons of operating VLAs at NYNJ from the perspectives of airline profitability, and flight delays at NYNJ and across the ATS.
An H1(Ph)-coercive discontinuous Galerkin formulation for the Poisson problem: 1D analysis
Zee, van der K.G.; Brummelen, van E.H.; Borst, de R.
2006-01-01
Coercivity of the bilinear form in a continuum variational problem is a fundamental property for finite-element discretizations: By the classical Lax–Milgram theorem, any conforming discretization of a coercive variational problem is stable; i.e., discrete approximations are well-posed and possess
An H1(Ph)-Coercive Discontinuous Galerkin Formulation for The Poisson Problem : 1-D Analysis
Van der Zee, K.G.; Van Brummelen, E.H.; De Borst, R.
2006-01-01
Coercivity of the bilinear form in a continuum variational problem is a fundamental property for finite-element discretizations: By the classical Lax–Milgram theorem, any conforming discretization of a coercive variational problem is stable; i.e., discrete approximations are well-posed and possess
Formulations and exact algorithms for the vehicle routing problem with time windows
DEFF Research Database (Denmark)
Kallehauge, Brian
2008-01-01
In this paper we review the exact algorithms proposed in the last three decades for the solution of the vehicle routing problem with time windows (VRPTW). The exact algorithms for the VRPTW are in many aspects inherited from work on the traveling salesman problem (TSP). In recognition of this fact...
On the formulation and numerical simulation of distributed-order fractional optimal control problems
Zaky, M. A.; Machado, J. A. Tenreiro
2017-11-01
In a fractional optimal control problem, the integer order derivative is replaced by a fractional order derivative. The fractional derivative embeds implicitly the time delays in an optimal control process. The order of the fractional derivative can be distributed over the unit interval, to capture delays of distinct sources. The purpose of this paper is twofold. Firstly, we derive the generalized necessary conditions for optimal control problems with dynamics described by ordinary distributed-order fractional differential equations (DFDEs). Secondly, we propose an efficient numerical scheme for solving an unconstrained convex distributed optimal control problem governed by the DFDE. We convert the problem under consideration into an optimal control problem governed by a system of DFDEs, using the pseudo-spectral method and the Jacobi-Gauss-Lobatto (J-G-L) integration formula. Next, we present the numerical solutions for a class of optimal control problems of systems governed by DFDEs. The convergence of the proposed method is graphically analyzed showing that the proposed scheme is a good tool for the simulation of distributed control problems governed by DFDEs.
On the Hardest Problem Formulations for the 0/1 Lasserre Hierarchy
Kurpisz, Adam; Leppänen, Samuli; Mastrolilli, Monaldo
2015-01-01
The Lasserre/Sum-of-Squares (SoS) hierarchy is a systematic procedure for constructing a sequence of increasingly tight semidefinite relaxations. It is known that the hierarchy converges to the 0/1 polytope in n levels and captures the convex relaxations used in the best available approximation algorithms for a wide variety of optimization problems. In this paper we characterize the set of 0/1 integer linear problems and unconstrained 0/1 polynomial optimization problems that can still have ...
International Nuclear Information System (INIS)
Morgan, W.C.
1996-01-01
This paper chronicles the history of the Hanford Production Reactor, from the initial design considerations for B, D, and F Reactors through the selection of the agreed method for safe disposal of the decommissioned reactors. The operational problems that challenged the operations and support staff of each new generation of production reactors, the engineering actions an operational changes that alleviated or resolved the immediate problems, the changes in reactor design and design-bases for the next generation of production reactors, and the changes in manufacturing variables that resulted in new ''improved'' grades of nuclear graphites for use in the moderators of the Hanford Production Reactors are reviewed in the context of the existing knowledge-base and the mission-driven priorities on the time. 14 refs, 6 figs, 3 tabs
Divergence identities in curved space-time. A resolution of the stress-energy problem
International Nuclear Information System (INIS)
Yilmaz, H.; Tufts Univ., Medford, MA
1989-01-01
It is noted that the joint use of two basic differential identities in curved space-time, namely. 1) the Einstein-Hilbert identity (1915), and 2) the identity of P. Freud (1939), permits a viable alternative to general relativity and a resolution of the field stress-energy' problem of the gravitational theory. (orig.)
A review of scheduling problem and resolution methods in flexible flow shop
Directory of Open Access Journals (Sweden)
Tian-Soon Lee
2019-01-01
Full Text Available The Flexible flow shop (FFS is defined as a multi-stage flow shops with multiple parallel machines. FFS scheduling problem is a complex combinatorial problem which has been intensively studied in many real world industries. This review paper gives a comprehensive exploration review on the FFS scheduling problem and guides the reader by considering and understanding different environmental assumptions, system constraints and objective functions for future research works. The published papers are classified into two categories. First is the FFS system characteristics and constraints including the problem differences and limitation defined by different studies. Second, the scheduling performances evaluation are elaborated and categorized into time, job and multi related objectives. In addition, the resolution approaches that have been used to solve FFS scheduling problems are discussed. This paper gives a comprehensive guide for the reader with respect to future research work on the FFS scheduling problem.
Solving inverse problems through a smooth formulation of multiple-point geostatistics
DEFF Research Database (Denmark)
Melnikova, Yulia
be inferred, for instance, from a conceptual geological model termed a training image.The main motivation for this study was the challenge posed by history matching, an inverse problem aimed at estimating rock properties from production data. We addressed two main difficulties of the history matching problem...... corresponding inverse problems. However, noise in data, non-linear relationships and sparse observations impede creation of realistic reservoir models. Including complex a priori information on reservoir parameters facilitates the process of obtaining acceptable solutions. Such a priori knowledge may...... strategies including both theoretical motivation and practical aspects of implementation. Finally, it is complemented by six research papers submitted, reviewed and/or published in the period 2010 - 2013....
Robust and Reliable Portfolio Optimization Formulation of a Chance Constrained Problem
Directory of Open Access Journals (Sweden)
Sengupta Raghu Nandan
2017-02-01
Full Text Available We solve a linear chance constrained portfolio optimization problem using Robust Optimization (RO method wherein financial script/asset loss return distributions are considered as extreme valued. The objective function is a convex combination of portfolio’s CVaR and expected value of loss return, subject to a set of randomly perturbed chance constraints with specified probability values. The robust deterministic counterpart of the model takes the form of Second Order Cone Programming (SOCP problem. Results from extensive simulation runs show the efficacy of our proposed models, as it helps the investor to (i utilize extensive simulation studies to draw insights into the effect of randomness in portfolio decision making process, (ii incorporate different risk appetite scenarios to find the optimal solutions for the financial portfolio allocation problem and (iii compare the risk and return profiles of the investments made in both deterministic as well as in uncertain and highly volatile financial markets.
A note on the strong formulation of stochastic control problems with model uncertainty
Sirbu, Mihai
2014-01-01
We consider a Markovian stochastic control problem with model uncertainty. The controller (intelligent player) observes only the state, and, therefore, uses feedback (closed-loop) strategies. The adverse player (nature) who does not have a direct interest in the payoff, chooses open-loop controls that parametrize Knightian uncertainty. This creates a two-step optimization problem (like half of a game) over feedback strategies and open-loop controls. The main result is to sh...
Nodal deterministic simulation for problems of neutron shielding in multigroup formulation
International Nuclear Information System (INIS)
Baptista, Josue Costa; Heringer, Juan Diego dos Santos; Santos, Luiz Fernando Trindade; Alves Filho, Hermes
2013-01-01
In this paper, we propose the use of some computational tools, with the implementation of numerical methods SGF (Spectral Green's Function), making use of a deterministic model of transport of neutral particles in the study and analysis of a known and simplified problem of nuclear engineering, known in the literature as a problem of neutron shielding, considering the model with two energy groups. These simulations are performed in MatLab platform, version 7.0, and are presented and developed with the help of a Computer Simulator providing a friendly computer application for their utilities
Rouwette, E.A.J.A.; Vennix, J.A.M.; Felling, A.J.A.
2009-01-01
In the past decade there has been a discussion on the need for and degree of empirical evidence for the effectiveness of problem structuring methods (PSMs). Some authors propose that PSMs are used in unique situations which are difficult to study, both from a methodological and a practical
Rouwette, E.A.J.A.; Vennix, J.A.M.; Felling, A.J.A.
2009-01-01
In the past decade there has been a discussion on the need for and degree of empirical evidence for the effectiveness of problem structuring methods (PSMs). Some authors propose that PSMs are used in unique situations which are difficult to study, both from a methodological and a practical
Formulations and Branch-and-Cut Algorithms for the Generalized Vehicle Routing Problem
DEFF Research Database (Denmark)
Bektas, Tolga; Erdogan, Günes; Røpke, Stefan
2011-01-01
The Generalized Vehicle Routing Problem (GVRP) consists of nding a set of routes for a number of vehicles with limited capacities on a graph with the vertices partitioned into clusters with given demands such that the total cost of travel is minimized and all demands are met. This paper offers four...
Barbagallo, Annamaria; Di Meglio, Guglielmo; Mauro, Paolo
2017-07-01
The aim of the paper is to study, in a Hilbert space setting, a general random oligopolistic market equilibrium problem in presence of both production and demand excesses and to characterize the random Cournot-Nash equilibrium principle by means of a stochastic variational inequality. Some existence results are presented.
Integer Programming Formulation of the Problem of Generating Milton Babbitt's All-partition Arrays
DEFF Research Database (Denmark)
Tanaka, Tsubasa; Bemman, Brian; Meredith, David
2016-01-01
Milton Babbitt (1916–2011) was a composer of twelve-tone serial music noted for creating the all-partition array. The problem of generating an all-partition array involves finding a rectangular array of pitch-class integers that can be partitioned into regions, each of which represents a distinct...
International Nuclear Information System (INIS)
Carmo, E.G.D. do; Galeao, A.C.N.R.
1986-01-01
A new method specially designed to solve highly convective transport problems is proposed. Using a variational approach it is shown that this weighted residual method belongs to a class of Petrov-Galerkin's approximation. Some examples are presented in order to demonstrate the adequacy of this method in predicting internal or external boundary layers. (Author) [pt
International Nuclear Information System (INIS)
Bagrov, V.G.; Evseevich, A.A.; Obukhov, V.V.; Osetrin, K.E.
1987-01-01
The authors consider the problem of the classification of the Stackel spaces of the electrovacuum with isotropic complete sets. The metrics of the spaces are represented in a form that is convenient for their investigation. We obtain necessary relations for the construction of the field equations
DEFF Research Database (Denmark)
Petersen, Hanne Løhmann; Madsen, Oli B.G.
2009-01-01
This paper introduces the double travelling salesman problem with multiple stacks and presents four different metaheuristic approaches to its solution. The double TSP with multiple stacks is concerned with determining the shortest route performing pickups and deliveries in two separated networks...
Oza, Amit R.
The focus of this study is to improve R&D effectiveness towards aerospace and defense planning in the early stages of the product development lifecycle. Emphasis is on: correct formulation of a decision problem, with special attention to account for data relationships between the individual design problem and the system capability required to size the aircraft, understanding of the meaning of the acquisition strategy objective and subjective data requirements that are required to arrive at a balanced analysis and/or "correct" mix of technology projects, understanding the meaning of the outputs that can be created from the technology analysis, and methods the researcher can use at effectively support decisions at the acquisition and conceptual design levels through utilization of a research and development portfolio strategy. The primary objectives of this study are to: (1) determine what strategy should be used to initialize conceptual design parametric sizing processes during requirements analysis for the materiel solution analysis stage of the product development lifecycle when utilizing data already constructed in the latter phase when working with a generic database management system synthesis tool integration architecture for aircraft design , and (2) assess how these new data relationships can contribute for innovative decision-making when solving acquisition hardware/technology portfolio problems. As such, an automated composable problem formulation system is developed to consider data interactions for the system architecture that manages acquisition pre-design concept refinement portfolio management, and conceptual design parametric sizing requirements. The research includes a way to: • Formalize the data storage and implement the data relationship structure with a system architecture automated through a database management system. • Allow for composable modeling, in terms of level of hardware abstraction, for the product model, mission model, and
DEFF Research Database (Denmark)
Uchoa, Eduardo; Fukasawa, Ricardo; Lysgaard, Jens
2008-01-01
-polynomial time. Traditional inequalities over the arc formulation, like Capacity Cuts, are also used. Moreover, a novel feature is introduced in such kind of algorithms: powerful new cuts expressed over a very large set of variables are added, without increasing the complexity of the pricing subproblem......This paper presents a robust branch-cut-and-price algorithm for the Capacitated Minimum Spanning Tree Problem (CMST). The variables are associated to q-arbs, a structure that arises from a relaxation of the capacitated prize-collecting arborescence problem in order to make it solvable in pseudo...... or the size of the LPs that are actually solved. Computational results on benchmark instances from the OR-Library show very significant improvements over previous algorithms. Several open instances could be solved to optimality....
2012-09-13
46, 1989. [75] S. Melkote and M.S. Daskin . An integrated model of facility location and transportation network design. Transportation Research Part A ... a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT/DS/ENS/12-09 THE AVERAGE NETWORK FLOW PROBLEM...focused thinking (VFT) are used sparingly, as is the case across the entirety of the supply chain literature. We provide a VFT tutorial for supply chain
Directory of Open Access Journals (Sweden)
KharchenkoV.V.
2014-12-01
Full Text Available The results of calculating the stress state of a hollow cylinder with a defect in the form of cracks, which is at the top of the cavity in the elastic-plastic formulation is presented. The calculation results are compared with the results of solving this problem in the elastic formulation vand with the results of solving the problem of the stretching cylinder with a crack.
KharchenkoV.V.; Ban’koS.N.; KobelskyS.V.; KravchenkoV.I.
2014-01-01
The results of calculating the stress state of a hollow cylinder with a defect in the form of cracks, which is at the top of the cavity in the elastic-plastic formulation is presented. The calculation results are compared with the results of solving this problem in the elastic formulation vand with the results of solving the problem of the stretching cylinder with a crack.
Three-dimensional formulation of the relativistic two-body problem in terms of rapidities
International Nuclear Information System (INIS)
Amirkhanov, I.V.; Grusha, G.V.; Mir-Kasimov, R.M.
1976-01-01
The scheme, based on the three-dimensional relativistic equation of the quasi-potential type is developed. As a basic variable rapidity, canonically conjugated to the relativistic relative distance is adopted. The free Green function has a simple pole in the complex rapidity plane, ensuring the fulfillment of the elastic unitarity for real potentials. In the local potential case the corresponding partial wave equation in configurational r-representation is a differential second-order equation. The problem of boundary conditions, which is a non-trivial one in the relativistic r-space, is studied. The exact solutions of the equation in simple cases have been found
DEFF Research Database (Denmark)
Cetin, Bilge Kartal; Prasad, Neeli R.; Prasad, Ramjee
2011-01-01
In wireless sensor networks, one of the key challenge is to achieve minimum energy consumption in order to maximize network lifetime. In fact, lifetime depends on many parameters: the topology of the sensor network, the data aggregation regime in the network, the channel access schemes, the routing...... protocols, and the energy model for transmission. In this paper, we tackle the routing challenge for maximum lifetime of the sensor network. We introduce a novel linear programming approach to the maximum lifetime routing problem. To the best of our knowledge, this is the first mathematical programming...
Directory of Open Access Journals (Sweden)
Rafael Grosso
2018-01-01
Full Text Available The application of the principles of sustainability to the implementation of urban freight policies requires the estimation of all the costs and externalities involved. We focus here on the case of access time windows, which ban the access of freight vehicles to central urban areas in many European cities. Even though this measure seeks to reduce congestion and emissions in the most crowded periods of the day, it also imposes additional costs for carriers and results in higher emissions and energy consumption. We present here a mathematical model for the Vehicle Routing Problem with Access Time Windows, a variant of the VRP suitable for planning delivery routes in a city subject to this type of accessibility restriction. We use the model to find exact solutions to small problem instances based on a case study and then compare the performance over larger instances of a modified savings algorithm, a genetic algorithm, and a tabu search procedure, with the results showing no clear prevalence of any of them, but confirming the significance of those additional costs and externalities.
Energy Technology Data Exchange (ETDEWEB)
Tres, Anderson [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Matematica Aplicada; Becker Picoloto, Camila [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Prolo Filho, Joao Francisco [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Inst de Matematica, Estatistica e Fisica; Dias da Cunha, Rudnei; Basso Barichello, Liliane [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Inst de Matematica
2014-04-15
In this work a study of two-dimensional fixed-source neutron transport problems, in Cartesian geometry, is reported. The approach reduces the complexity of the multidimensional problem using a combination of nodal schemes and the Analytical Discrete Ordinates Method (ADO). The unknown leakage terms on the boundaries that appear from the use of the derivation of the nodal scheme are incorporated to the problem source term, such as to couple the one-dimensional integrated solutions, made explicit in terms of the x and y spatial variables. The formulation leads to a considerable reduction of the order of the associated eigenvalue problems when combined with the usual symmetric quadratures, thereby providing solutions that have a higher degree of computational efficiency. Reflective-type boundary conditions are introduced to represent the domain on a simpler form than that previously considered in connection with the ADO method. Numerical results obtained with the technique are provided and compared to those present in the literature. (orig.)
Mathematical modelling and numerical resolution of multi-phase compressible fluid flows problems
International Nuclear Information System (INIS)
Lagoutiere, Frederic
2000-01-01
This work deals with Eulerian compressible multi-species fluid dynamics, the species being either mixed or separated (with interfaces). The document is composed of three parts. The first parts devoted to the numerical resolution of model problems: advection equation, Burgers equation, and Euler equations, in dimensions one and two. The goal is to find a precise method, especially for discontinuous initial conditions, and we develop non dissipative algorithms. They are based on a downwind finite-volume discretization under some stability constraints. The second part treats of the mathematical modelling of fluids mixtures. We construct and analyse a set of multi-temperature and multi-pressure models that are entropy, symmetrizable, hyperbolic, not ever conservative. In the third part, we apply the ideas developed in the first part (downwind discretization) to the numerical resolution of the partial differential problems we have constructed for fluids mixtures in the second part. We present some numerical results in dimensions one and two. (author) [fr
Approximation in generalized Hardy classes and resolution of inverse problems for tokamaks
International Nuclear Information System (INIS)
Fisher, Y.
2011-11-01
This thesis concerns both the theoretical and constructive resolution of inverse problems for isotropic diffusion equation in planar domains, simply and doubly connected. From partial Cauchy boundary data (potential, flux), we look for those quantities on the remaining part of the boundary, where no information is available, as well as inside the domain. The proposed approach proceeds by considering solutions to the diffusion equation as real parts of complex valued solutions to some conjugated Beltrami equation. These particular generalized analytic functions allow to introduce Hardy classes, where the inverse problem is stated as a best constrained approximation issue (bounded extrema problem), and thereby is regularized. Hence, existence and smoothness properties, together with density results of traces on the boundary, ensure well-posedness. An application is studied, to a free boundary problem for a magnetically confined plasma in the tokamak Tore Supra (CEA Cadarache France). The resolution of the approximation problem on a suitable basis of functions (toroidal harmonics) leads to a qualification criterion for the estimated plasma boundary. A descent algorithm makes it decrease, and refines the estimations. The method does not require any integration of the solution in the overall domain. It furnishes very accurate numerical results, and could be extended to other devices, like JET or ITER. (author)
International Nuclear Information System (INIS)
Smith, Kyle K. G.; Poulsen, Jens Aage; Nyman, Gunnar; Rossky, Peter J.
2015-01-01
We develop two classes of quasi-classical dynamics that are shown to conserve the initial quantum ensemble when used in combination with the Feynman-Kleinert approximation of the density operator. These dynamics are used to improve the Feynman-Kleinert implementation of the classical Wigner approximation for the evaluation of quantum time correlation functions known as Feynman-Kleinert linearized path-integral. As shown, both classes of dynamics are able to recover the exact classical and high temperature limits of the quantum time correlation function, while a subset is able to recover the exact harmonic limit. A comparison of the approximate quantum time correlation functions obtained from both classes of dynamics is made with the exact results for the challenging model problems of the quartic and double-well potentials. It is found that these dynamics provide a great improvement over the classical Wigner approximation, in which purely classical dynamics are used. In a special case, our first method becomes identical to centroid molecular dynamics
International Nuclear Information System (INIS)
Castaneda M, V. H.; Martinez B, M. R.; Solis S, L. O.; Castaneda M, R.; Leon P, A. A.; Hernandez P, C. F.; Espinoza G, J. G.; Ortiz R, J. M.; Vega C, H. R.; Mendez, R.; Gallego, E.; Sousa L, M. A.
2016-10-01
The Taguchi methodology has proved to be highly efficient to solve inverse problems, in which the values of some parameters of the model must be obtained from the observed data. There are intrinsic mathematical characteristics that make a problem known as inverse. Inverse problems appear in many branches of science, engineering and mathematics. To solve this type of problem, researches have used different techniques. Recently, the use of techniques based on Artificial Intelligence technology is being explored by researches. This paper presents the use of a software tool based on artificial neural networks of generalized regression in the solution of inverse problems with application in high energy physics, specifically in the solution of the problem of neutron spectrometry. To solve this problem we use a software tool developed in the Mat Lab programming environment, which employs a friendly user interface, intuitive and easy to use for the user. This computational tool solves the inverse problem involved in the reconstruction of the neutron spectrum based on measurements made with a Bonner spheres spectrometric system. Introducing this information, the neural network is able to reconstruct the neutron spectrum with high performance and generalization capability. The tool allows that the end user does not require great training or technical knowledge in development and/or use of software, so it facilitates the use of the program for the resolution of inverse problems that are in several areas of knowledge. The techniques of Artificial Intelligence present singular veracity to solve inverse problems, given the characteristics of artificial neural networks and their network topology, therefore, the tool developed has been very useful, since the results generated by the Artificial Neural Network require few time in comparison to other techniques and are correct results comparing them with the actual data of the experiment. (Author)
González Cornejo, Felipe A.; Cruchaga, Marcela A.; Celentano, Diego J.
2017-11-01
The present work reports a fluid-rigid solid interaction formulation described within the framework of a fixed-mesh technique. The numerical analysis is focussed on the study of a vortex-induced vibration (VIV) of a circular cylinder at low Reynolds number. The proposed numerical scheme encompasses the fluid dynamics computation in an Eulerian domain where the body is embedded using a collection of markers to describe its shape, and the rigid solid's motion is obtained with the well-known Newton's law. The body's velocity is imposed on the fluid domain through a penalty technique on the embedded fluid-solid interface. The fluid tractions acting on the solid are computed from the fluid dynamic solution of the flow around the body. The resulting forces are considered to solve the solid motion. The numerical code is validated by contrasting the obtained results with those reported in the literature using different approaches for simulating the flow past a fixed circular cylinder as a benchmark problem. Moreover, a mesh convergence analysis is also done providing a satisfactory response. In particular, a VIV problem is analyzed, emphasizing the description of the synchronization phenomenon.
De Kruijf, J.
2007-01-01
Water management issues are often complex, unstructured problems. They are complex, because they are part of a natural and human system wich consists of many diverse, interdependent elements, e.g. upstream events influence the water system downstream, different interdependent goverment layers,
International Nuclear Information System (INIS)
Biedenharn, L.C.; Lohe, M.A.; Louck, J.D.
1975-01-01
The multiplicity problem for tensor operators in U(3) has a unique (canonical) resolution which is utilized to effect the explicit construction of all U(3) Wigner and Racah coefficients. Methods are employed which elucidate the structure of the results; in particular, the significance of the denominator functions entering the structure of these coefficients, and the relation of these denominator functions to the null space of the canonical tensor operators. An interesting feature of the denominator functions is the appearance of new, group theoretical, polynomials exhibiting several remarkable and quite unexpected properties. (U.S.)
Proximal methods for the resolution of inverse problems: application to positron emission tomography
International Nuclear Information System (INIS)
Pustelnik, N.
2010-12-01
The objective of this work is to propose reliable, efficient and fast methods for minimizing convex criteria, that are found in inverse problems for imagery. We focus on restoration/reconstruction problems when data is degraded with both a linear operator and noise, where the latter is not assumed to be necessarily additive.The reliability of the method is ensured through the use of proximal algorithms, the convergence of which is guaranteed when a convex criterion is considered. Efficiency is sought through the choice of criteria adapted to the noise characteristics, the linear operators and the image specificities. Of particular interest are regularization terms based on total variation and/or sparsity of signal frame coefficients. As a consequence of the use of frames, two approaches are investigated, depending on whether the analysis or the synthesis formulation is chosen. Fast processing requirements lead us to consider proximal algorithms with a parallel structure. Theoretical results are illustrated on several large size inverse problems arising in image restoration, stereoscopy, multi-spectral imagery and decomposition into texture and geometry components. We focus on a particular application, namely Positron Emission Tomography (PET), which is particularly difficult because of the presence of a projection operator combined with Poisson noise, leading to highly corrupted data. To optimize the quality of the reconstruction, we make use of the spatio-temporal characteristics of brain tissue activity. (author)
Energy Technology Data Exchange (ETDEWEB)
Pereira, Luis Carlos Martins
1998-06-15
New Petrov-Galerkin formulations on the finite element methods for convection-diffusion problems with boundary layers are presented. Such formulations are based on a consistent new theory on discontinuous finite element methods. Existence and uniqueness of solutions for these problems in the new finite element spaces are demonstrated. Some numerical experiments shows how the new formulation operate and also their efficacy. (author)
Directory of Open Access Journals (Sweden)
V. S. Zarubin
2016-01-01
dependence of the absorption factor on the local intensity of this radiation. Furthermore, it can be a significant dependence of this factor on the local value of the material temperature, reflecting the above-mentioned relationship between the absorption of electromagnetic wave energy and the excitation of material microparticles. This process can be described by Boltzmann distribution function that comprises the energy to activate microparticles and the local value of temperature.This paper presents a variational formulation of the nonlinear problem of stationary heat conduction in a plate for the case when the radiation reduction factor in relation to the Bouguer law depends on the local temperature. This formulation includes a functional that can have several fixed points corresponding to different steady states of the plate temperature. Analysis of the properties of this functional enabled us to identify the stationary points, which correspond to the realized temperature distribution in the plate.
Sampaio Oliveira, A.H.; Urrutia, S.
2017-01-01
In this paper, we consider the pickup and delivery traveling salesman problem with multiple stacks in which a single vehicle must serve a set of customer requests defined by a pair of pickup and delivery destinations of an item. The vehicle contains a fixed number of stacks, where each item is
Directory of Open Access Journals (Sweden)
Gogina Elena Sergeevna
2012-12-01
big cities of Russia. At the same time, the quality of the waste water treated by local water treatment stations fails to meet the present-day standard requirements. Moreover, potable water shall not be used for the purpose of washing transport vehicles. Within the recent 10 years, MGSU has developed a number of research projects aimed at the resolution of this problem. The concept developed by the MGSU specialists is to attain the highest quality of treated waste water generated by car washes and transport enterprises using the most advanced technologies of water treatment rather than to design new water treatment plants. Various methods may be applied for this purpose: restructuring of water treatment facilities, advanced feed, updated regulations governing the operation of water treatment plants.
Nuclear waste disposal: Can there be a resolution? Past problems and future solutions
Energy Technology Data Exchange (ETDEWEB)
Ahearne, J [Scientific Research Society, Sigma Xi, Research Triangle Park, NC (United States)
1990-07-01
Why does the high level waste problem have to be solved now? There are perhaps three answers to that question. First, to have a recovery of nuclear power. But a lack of resolution of the high level waste problem is not the principal reason that nuclear power has foundered and, consequently, solving it will not automatically revive nuclear power. However, if the nuclear industry is adamantly convinced that this is the key to reviving nuclear power, then the nuclear industry should demonstrate its conviction by putting much greater effort into resolving the high level waste problem technically, not through public relations. For example, a substantial effort on the actinide burning approach might demonstrate, in the old American phrase, 'putting your money where your mouth is'. Second, the high level waste problem must be solved now because it is a devil's brew. However, chemical wastes last longer, as we all know, than do the radioactive wastes. As one expert has noted: 'There is real risk in nuclear power, just as there is real risk in coal power.... For some of [these risks], like the greenhouse effect, the potential damage is devastating. While for others, like nuclear accidents, the risk is limited, but imaginations are not. For still others, like the risk posed by a high-level waste repository, there is essentially nothing outside the imagination of the gullible.' Furthermore, any technical solution or any solution to a risky problem requires one to think carefully. It is often better to do it right than quickly. A third reason for requiring it to be solved right now is that HLW disposal is a major technical problem blocking a potentially valuable energy source. But we need a new solution. The current solutions are not working. I believe that we ought to recognize the failure of the geologic repository approach. I believe the federal government should identify, with industry's assistance, the best techniques for surface storage. Some federal locations should be
Nuclear waste disposal: Can there be a resolution? Past problems and future solutions
International Nuclear Information System (INIS)
Ahearne, J.
1990-01-01
Why does the high level waste problem have to be solved now? There are perhaps three answers to that question. First, to have a recovery of nuclear power. But a lack of resolution of the high level waste problem is not the principal reason that nuclear power has foundered and, consequently, solving it will not automatically revive nuclear power. However, if the nuclear industry is adamantly convinced that this is the key to reviving nuclear power, then the nuclear industry should demonstrate its conviction by putting much greater effort into resolving the high level waste problem technically, not through public relations. For example, a substantial effort on the actinide burning approach might demonstrate, in the old American phrase, 'putting your money where your mouth is'. Second, the high level waste problem must be solved now because it is a devil's brew. However, chemical wastes last longer, as we all know, than do the radioactive wastes. As one expert has noted: 'There is real risk in nuclear power, just as there is real risk in coal power.... For some of [these risks], like the greenhouse effect, the potential damage is devastating. While for others, like nuclear accidents, the risk is limited, but imaginations are not. For still others, like the risk posed by a high-level waste repository, there is essentially nothing outside the imagination of the gullible.' Furthermore, any technical solution or any solution to a risky problem requires one to think carefully. It is often better to do it right than quickly. A third reason for requiring it to be solved right now is that HLW disposal is a major technical problem blocking a potentially valuable energy source. But we need a new solution. The current solutions are not working. I believe that we ought to recognize the failure of the geologic repository approach. I believe the federal government should identify, with industry's assistance, the best techniques for surface storage. Some federal locations should be
Ballard, Patrick; Charles, Alexandre
2018-03-01
In the end of the seventies, Schatzman and Moreau undertook to revisit the venerable dynamics of rigid bodies with contact and dry friction in the light of more recent mathematics. One claimed objective was to reach, for the first time, a mathematically consistent formulation of an initial value problem associated with the dynamics. The purpose of this article is to make a review of the today state-of-art concerning not only the formulation, but also the issues of existence and uniqueness of solution. xml:lang="fr"
Charles, Alexandre; Ballard, Patrick
2016-08-01
The dynamics of mechanical systems with a finite number of degrees of freedom (discrete mechanical systems) is governed by the Lagrange equation which is a second-order differential equation on a Riemannian manifold (the configuration manifold). The handling of perfect (frictionless) unilateral constraints in this framework (that of Lagrange's analytical dynamics) was undertaken by Schatzman and Moreau at the beginning of the 1980s. A mathematically sound and consistent evolution problem was obtained, paving the road for many subsequent theoretical investigations. In this general evolution problem, the only reaction force which is involved is a generalized reaction force, consistently with the virtual power philosophy of Lagrange. Surprisingly, such a general formulation was never derived in the case of frictional unilateral multibody dynamics. Instead, the paradigm of the Coulomb law applying to reaction forces in the real world is generally invoked. So far, this paradigm has only enabled to obtain a consistent evolution problem in only some very few specific examples and to suggest numerical algorithms to produce computational examples (numerical modeling). In particular, it is not clear what is the evolution problem underlying the computational examples. Moreover, some of the few specific cases in which this paradigm enables to write down a precise evolution problem are known to show paradoxes: the Painlevé paradox (indeterminacy) and the Kane paradox (increase in kinetic energy due to friction). In this paper, we follow Lagrange's philosophy and formulate the frictional unilateral multibody dynamics in terms of the generalized reaction force and not in terms of the real-world reaction force. A general evolution problem that governs the dynamics is obtained for the first time. We prove that all the solutions are dissipative; that is, this new formulation is free of Kane paradox. We also prove that some indeterminacy of the Painlevé paradox is fixed in this
Solving the problem of imaging resolution: stochastic multi-scale image fusion
Karsanina, Marina; Mallants, Dirk; Gilyazetdinova, Dina; Gerke, Kiril
2016-04-01
Structural features of porous materials define the majority of its physical properties, including water infiltration and redistribution, multi-phase flow (e.g. simultaneous water/air flow, gas exchange between biologically active soil root zone and atmosphere, etc.) and solute transport. To characterize soil and rock microstructure X-ray microtomography is extremely useful. However, as any other imaging technique, this one also has a significant drawback - a trade-off between sample size and resolution. The latter is a significant problem for multi-scale complex structures, especially such as soils and carbonates. Other imaging techniques, for example, SEM/FIB-SEM or X-ray macrotomography can be helpful in obtaining higher resolution or wider field of view. The ultimate goal is to create a single dataset containing information from all scales or to characterize such multi-scale structure. In this contribution we demonstrate a general solution for merging multiscale categorical spatial data into a single dataset using stochastic reconstructions with rescaled correlation functions. The versatility of the method is demonstrated by merging three images representing macro, micro and nanoscale spatial information on porous media structure. Images obtained by X-ray microtomography and scanning electron microscopy were fused into a single image with predefined resolution. The methodology is sufficiently generic for implementation of other stochastic reconstruction techniques, any number of scales, any number of material phases, and any number of images for a given scale. The methodology can be further used to assess effective properties of fused porous media images or to compress voluminous spatial datasets for efficient data storage. Potential practical applications of this method are abundant in soil science, hydrology and petroleum engineering, as well as other geosciences. This work was partially supported by RSF grant 14-17-00658 (X-ray microtomography study of shale
A Bi-Modal Routing Problem with Cyclical and One-Way Trips: Formulation and Heuristic Solution
Directory of Open Access Journals (Sweden)
Grinde Roger B.
2017-12-01
Full Text Available A bi-modal routing problem is solved using a heuristic approach. Motivated by a recreational hiking application, the problem is similar to routing problems in business with two transport modes. The problem decomposes into a set covering problem (SCP and an asymmetric traveling salesperson problem (ATSP, corresponding to a hiking time objective and a driving distance objective. The solution algorithm considers hiking time first, but finds all alternate optimal solutions, as inputs to the driving distance problem. Results show the trade-offs between the two objectives.
Directory of Open Access Journals (Sweden)
Lyakhovich Leonid
2017-01-01
Full Text Available This paper is devoted to formulation and general principles of approximation of multipoint boundary problem of static analysis of deep beam with the use of combined application of finite element method (FEM discrete-continual finite element method (DCFEM. The field of application of DCFEM comprises structures with regular physical and geometrical parameters in some dimension (“basic” dimension. DCFEM presupposes finite element approximation for non-basic dimension while in the basic dimension problem remains continual. DCFEM is based on analytical solutions of resulting multipoint boundary problems for systems of ordinary differential equations with piecewise-constant coefficients.
«Economic rights» as a result of the makrosystemth process in the law: formulation of the problem
Directory of Open Access Journals (Sweden)
Юлія Ігорівна Остапенко
2016-06-01
Full Text Available The article analyzes the dynamic development of legislation in the field of economic relations is matched to structural transformation in the law, and therefore the law, and legislation is organically linked. Аs a consequence, become structurally tumors in the legal system as a key emerging trend of improving its evolyutsinuvannya. In this sense, the normative legal provision of economic relations – is a complete standalone system, it is appropriate to determine as the only legal complex object. It is established that it is considering systematic in identifying major and minor aspects of the legal functioning of the economic system we can talk about high efficiency of legal regulation of the global economic system. Proved that despite the complex hierarchical nature of relations in the economic system that tends to continuing specialization of its components, ensuring the interaction of all elements of the structure and output of its operation to set general parameters requires an integrative, holistic, coherent with the legal system and legal support in adequate to the problem of this magnitude format. Now the scientific legal literature began to explore some categorical concepts, some substantive mechanisms for the enhancement of the conceptual level that can be regarded as approval beliefs and understanding of the separation of such jurisprudence as Economic Law of Ukraine [1–11]. The rich have paid attention to this issue and scientists of Kharkiv Donetsk schools of law, namely:, D. V. Zadyhaylo, D. D. Zadyhaylo, V. S. Milash, V. A. Ustymenko and others. Also, this perspective was a range of scientific interests of Kiev and Odessa schools, namely A. M. Vinnik, O. P. Podtserkovnyy, V. S. Shcherbina and others. In the former Soviet Union it examined: A. Alpatov, G. Velyanovskyy, G. Balsevich, M. Odintsov, V. Tambovtsev and others. However, scientists have not paid sufficient attention, and the very conceptual analysis of the category of
CSIR Research Space (South Africa)
Shatalov, M
2012-09-01
Full Text Available are transformed into systems of ordinary differential equations with initial conditions. This reduction is obtained by means of application of particular finite difference schemes to the spatial derivatives. Many of the wave propagation problems describing...
Directory of Open Access Journals (Sweden)
Akimov Pavel Alekseevich
2012-10-01
Full Text Available The proposed paper covers the operator-related formulation of the eigenvalue problem of analysis of a three-dimensional structure that has piecewise-constant physical and geometrical parameters alongside the so-called basic direction within the framework of a discrete-continual approach (a discrete-continual finite element method, a discrete-continual variation method. Generally, discrete-continual formulations represent contemporary mathematical models that become available for computer implementation. They make it possible for a researcher to consider the boundary effects whenever particular components of the solution represent rapidly varying functions. Another feature of discrete-continual methods is the absence of any limitations imposed on lengths of structures. The three-dimensional problem of elasticity is used as the design model of a structure. In accordance with the so-called method of extended domain, the domain in question is embordered by an extended one of an arbitrary shape. At the stage of numerical implementation, relative key features of discrete-continual methods include convenient mathematical formulas, effective computational patterns and algorithms, simple data processing, etc. The authors present their formulation of the problem in question for an isotropic medium with allowance for supports restrained by elastic elements while standard boundary conditions are also taken into consideration.
International Nuclear Information System (INIS)
Khorrami, M.
1995-01-01
A general formulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum mechanics (due to noncommutativity of the operators), are no longer present here. Then the criteria for the unitarity of the evolution operator are examined. It is shown that the unitarity of the evolution operator puts restrictions on the form of the action, and also implies the existence of a solution for the classical initial-value problem. 13 refs
Tucker, Jalie A.; Roth, David L.; Huang, Jin; Scott Crawford, M.; Simpson, Cathy A.
2012-01-01
Objective: Most problem drinkers do not seek help, and many recover on their own. A randomized controlled trial evaluated whether supportive interactive voice response (IVR) self-monitoring facilitated such “natural” resolutions. Based on behavioral economics, effects on drinking outcomes were hypothesized to vary with drinkers’ baseline “time horizons,” reflecting preferences among commodities of different value available over different delays and with their IVR utilization. Method: Recently resolved untreated problem drinkers were randomized to a 24-week IVR self-monitoring program (n = 87) or an assessment-only control condition (n = 98). Baseline interviews assessed outcome predictors including behavioral economic measures of reward preferences (delay discounting, pre-resolution monetary allocation to alcohol vs. savings). Six-month outcomes were categorized as resolved abstinent, resolved nonabstinent, unresolved, or missing. Complier average causal effect (CACE) models examined IVR self-monitoring effects. Results: IVR self-monitoring compliers (≥70% scheduled calls completed) were older and had greater pre-resolution drinking control and lower discounting than noncompliers (moderation than abstinent resolutions compared with predicted compliers in the control group with shorter time horizons and with all noncompliers. Intention-to-treat analytical models revealed no IVR-related effects. More balanced spending on savings versus alcohol predicted moderation in both approaches. Conclusions: IVR interventions should consider factors affecting IVR utilization and drinking outcomes, including person-specific behavioral economic variables. CACE models provide tools to evaluate interventions involving extended participation. PMID:22630807
DEFF Research Database (Denmark)
Iris, Cagatay; Pacino, Dario; Røpke, Stefan
2017-01-01
This paper focuses on the integrated berth allocation and quay crane assignment problem in container terminals. We consider the decrease in the marginal productivity of quay cranes and the increase in handling time due to deviation from the desired position. We consider a continuous berth...
Energy Technology Data Exchange (ETDEWEB)
Ganev, K; Yordanov, D
1983-01-01
The formulation of a diffusion problem for numerical models, in which the near earth layer of the atmosphere (PSA) is considered parametrically relative to the zones of pollution (the protected zones) which are also located in the near earth layer of atmosphere, is examined. In modeling atmospheric pollution, the semiempirical equation of turublent diffusion is the starting point. The results are cited of numerical calculations of the functions of the effect for the city of Sofia (the case of an even relief and the disposition of the protected zone totally within the region for which the problem is being solved). The isolines of the integral function of the effect relative to the near earth layer of the atmosphere above the city of Sofia are cited for different meteorological conditions.
International Nuclear Information System (INIS)
Efroymson, Rebecca Ann; Peterson, Mark J.; Jones, Daniel Steven; Suter, Glenn
2008-01-01
An ecological risk assessment was conducted at Yuma Proving Ground, Arizona, as a demonstration of the Military Ecological Risk Assessment Framework (MERAF). The focus of the assessment was a testing program at Cibola Range, which involved an Apache Longbow helicopter firing Hellfire missiles at moving targets, i.e., M60-A1 tanks. The problem formulation for the assessment included conceptual models for three component activities of the test, helicopter overflight, missile firing, and tracked vehicle movement, and two ecological endpoint entities, woody desert wash communities and desert mule deer (Odocoileus hemionus crooki) populations. An activity-specific risk assessment framework was available to provide guidance for assessing risks associated with aircraft overflights. Key environmental features of the study area include barren desert pavement and tree-lined desert washes. The primary stressors associated with helicopter overflights were sound and the view of the aircraft. The primary stressor associated with Hellfire missile firing was sound. The principal stressor associated with tracked vehicle movement was soil disturbance, and a resulting, secondary stressor was hydrological change. Water loss to washes and wash vegetation was expected to result from increased ponding, infiltration and/or evaporation associated with disturbances to desert pavement. A plan for estimating integrated risks from the three military activities was included in the problem formulation
International Nuclear Information System (INIS)
Mashhour, M.; Golkar, M.A.; Moghaddas-Tafreshi, S.M.
2011-01-01
This work presents a novel hourly-ahead profit model for an active distribution company (DISCO), a DISCO with high capacity level of connected DGs that can make selling proposals for the markets, in a pool-based system. The presented model engages DSICO in both energy producing and reserve providing activities. DISCO's earnings from reserve market include the remuneration both for real-time generation and ready-for-service capacity. To achieve the optimal decisions for an active DISCO in the energy and reserve markets, a two-stage optimization model and associated mathematical formulations have been developed. The first subproblem extracts a single operating profile (a lumped financial model) of the whole distribution system, including DGs and ILs, at the connecting point to the upstream network. The second one determines the optimal values of decision variables (power and reserve commodities) to maximize the DISCO's profit, in case such variables are accepted in the markets. In other words, it aims to optimally allocate the DISCO's generating capability for proposing into the energy and reserve markets, from the DISCO's perspective. It also proposes a profit-based network reconfiguration methodology for a multi-substation multi-feeder DISCO to increase DISCO's ability to gain more benefits from the market activities. It conducts DISCO's generating capabilities towards the proper substations to reap more probable benefits. It also introduces fast, simple, and straightforward algorithms for recognition and removal of configurations having loop and/or islanding parts in. Simulation results are given at the second part of the present work.
Directory of Open Access Journals (Sweden)
O. P. Mintser
2015-09-01
Full Text Available The article is devoted to functioning of the quality management by ISO 9001 standard. The problem of inefficient and non-working systems is pointed out, the causes of their inefficiency are investigated. The phenomenon of simultaneous existence of two parallel management systems: formal quality management system and living systems of managerial decisions making is studied. To study this situation the measure of «efficiency of quality management system» is introduced; further tasks for creating indicators and mechanisms for its evaluation are defined.
Energy Technology Data Exchange (ETDEWEB)
Berlinger, C. H.; Murphy, E. L. [United States Nuclear Regulatory Commission, Washington, D.C. 20555 (United States)
1986-02-15
Emergency standby diesel generators manufactured by Transamerica Delaval, Inc. experienced a number of major problems during preoperational qualification testing at several U.S. nuclear sites. Most notably these have included a complete fracture of a crankshaft, an engine block failure, piston failures, and cracked and leaking cylinder heads. These problems appear to stem from deficiencies in design and manufacturing quality by the engine manufacturer. This paper discusses some of the more significant problems experienced and actions taken by the nuclear utility owners and the NRC to reestablish confidence in the reliability of these engines and to qualify these engines for nuclear service. (authors)
International Nuclear Information System (INIS)
Berlinger, C.H.; Murphy, E.L.
1986-01-01
Emergency standby diesel generators manufactured by Transamerica Delaval, Inc. experienced a number of major problems during preoperational qualification testing at several U.S. nuclear sites. Most notably these have included a complete fracture of a crankshaft, an engine block failure, piston failures, and cracked and leaking cylinder heads. These problems appear to stem from deficiencies in design and manufacturing quality by the engine manufacturer. This paper discusses some of the more significant problems experienced and actions taken by the nuclear utility owners and the NRC to reestablish confidence in the reliability of these engines and to qualify these engines for nuclear service. (authors)
Directory of Open Access Journals (Sweden)
Ada Che
2008-01-01
Full Text Available Modern automated production lines usually use one or multiple computer-controlled robots or hoists for material handling between workstations. A typical application of such lines is an automated electroplating line for processing printed circuit boards (PCBs. In these systems, cyclic production policy is widely used due to large lot size and simplicity of implementation. This paper addresses cyclic scheduling of a multihoist electroplating line with constant processing times. The objective is to minimize the cycle time, or equivalently to maximize the production throughput, for a given number of hoists. We propose a mathematical model and a polynomial algorithm for this scheduling problem. Computational results on randomly generated instances are reported.
Scaling of Thermal Images at Different Spatial Resolution: The Mixed Pixel Problem
Directory of Open Access Journals (Sweden)
Hamlyn G. Jones
2014-07-01
Full Text Available The consequences of changes in spatial resolution for application of thermal imagery in plant phenotyping in the field are discussed. Where image pixels are significantly smaller than the objects of interest (e.g., leaves, accurate estimates of leaf temperature are possible, but when pixels reach the same scale or larger than the objects of interest, the observed temperatures become significantly biased by the background temperature as a result of the presence of mixed pixels. Approaches to the estimation of the true leaf temperature that apply both at the whole-pixel level and at the sub-pixel level are reviewed and discussed.
Dishion, Thomas J; Forgatch, Marion; Van Ryzin, Mark; Winter, Charlotte
2012-07-01
In this study we examined the videotaped family interactions of a community sample of adolescents and their parents. Youths were assessed in early to late adolescence on their levels of antisocial behavior. At age 16-17, youths and their parents were videotaped interacting while completing a variety of tasks, including family problem solving. The interactions were coded and compared for three developmental patterns of antisocial behavior: early onset, persistent; adolescence onset; and typically developing. The mean duration of conflict bouts was the only interaction pattern that discriminated the 3 groups. In the prediction of future antisocial behavior, parent and youth reports of transition entropy and conflict resolution interacted to account for antisocial behavior at age 18-19. Families with low entropy and peaceful resolutions predicted low levels of youth antisocial behavior at age 18-19. These findings suggest the need to study both attractors and repellers to understand family dynamics associated with health and social and emotional development.
Kim, Won Hwa; Chung, Moo K; Singh, Vikas
2013-01-01
The analysis of 3-D shape meshes is a fundamental problem in computer vision, graphics, and medical imaging. Frequently, the needs of the application require that our analysis take a multi-resolution view of the shape's local and global topology, and that the solution is consistent across multiple scales. Unfortunately, the preferred mathematical construct which offers this behavior in classical image/signal processing, Wavelets, is no longer applicable in this general setting (data with non-uniform topology). In particular, the traditional definition does not allow writing out an expansion for graphs that do not correspond to the uniformly sampled lattice (e.g., images). In this paper, we adapt recent results in harmonic analysis, to derive Non-Euclidean Wavelets based algorithms for a range of shape analysis problems in vision and medical imaging. We show how descriptors derived from the dual domain representation offer native multi-resolution behavior for characterizing local/global topology around vertices. With only minor modifications, the framework yields a method for extracting interest/key points from shapes, a surprisingly simple algorithm for 3-D shape segmentation (competitive with state of the art), and a method for surface alignment (without landmarks). We give an extensive set of comparison results on a large shape segmentation benchmark and derive a uniqueness theorem for the surface alignment problem.
Church, Ellen Booth
2005-01-01
This brief article describes how classroom group time can be "talk central" for children to discuss problems, imagine solutions, even role-play hypothetical situations. It is often in the safety and support of the large group that children develop the tools they need to learn how to resolve the inevitable conflicts that arise throughout life.…
Niaz, Mansoor
2001-01-01
Illustrates how a novel problem of chemical equilibrium based on a closely related sequence of items can facilitate students' conceptual understanding. Students were presented with a chemical reaction in equilibrium to which a reactant was added as an external effect. Three studies were conducted to assess alternative conceptions. (Author/SAH)
Energy Technology Data Exchange (ETDEWEB)
Basso Barichello, Liliane; Dias da Cunha, Rudnei [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Inst. de Matematica; Becker Picoloto, Camila [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Tres, Anderson [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Matematica Aplicada
2015-05-15
A nodal formulation of a fixed-source two-dimensional neutron transport problem, in Cartesian geometry, defined in a heterogeneous medium, is solved by an analytical approach. Explicit expressions, in terms of the spatial variables, are derived for averaged fluxes in each region in which the domain is subdivided. The procedure is an extension of an analytical discrete ordinates method, the ADO method, for the solution of the two-dimensional homogeneous medium case. The scheme is developed from the discrete ordinates version of the two-dimensional transport equation along with the level symmetric quadrature scheme. As usual for nodal schemes, relations between the averaged fluxes and the unknown angular fluxes at the contours are introduced as auxiliary equations. Numerical results are in agreement with results available in the literature.
Cierniak, Robert; Lorent, Anna
2016-09-01
The main aim of this paper is to investigate properties of our originally formulated statistical model-based iterative approach applied to the image reconstruction from projections problem which are related to its conditioning, and, in this manner, to prove a superiority of this approach over ones recently used by other authors. The reconstruction algorithm based on this conception uses a maximum likelihood estimation with an objective adjusted to the probability distribution of measured signals obtained from an X-ray computed tomography system with parallel beam geometry. The analysis and experimental results presented here show that our analytical approach outperforms the referential algebraic methodology which is explored widely in the literature and exploited in various commercial implementations. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fowler, A R; Bushardt, S C; Jones, M A
1993-06-01
The way nurses resolve conflict may be leading them to quit their jobs or leave the profession altogether. Conflict is inevitable in a dynamic organization. What is important is not to avoid conflict but to seek its resolution in a constructive manner. Organizational conflict is typically resolved through one of five strategies: withdrawal, force, conciliation, compromise, or confrontation. A recent study of nurses in three different hospitals showed that the approach they use most is withdrawal. This might manifest itself in a request to change shifts or assignments and may lead to a job change and, eventually, abandonment of the field altogether. Given this scenario, changing nurses' conflict resolution style may help administrators combat the nursing shortage. Healthcare organizations must examine themselves to determine why nurses so frequently use withdrawal; then they must restructure work relationships as needed. Next, organizations need to increase nurses' awareness of the problem and train them to use a resolution style more conducive to building stable relationships: confrontation. Staff should also be trained in effective communications skills to develop trust and openness in their relationships.
Energy Technology Data Exchange (ETDEWEB)
Ueda, Shoichi; Yano, Katsuhiko
1961-03-01
As a part of ABCC's research program to review the general hypothesis that radiation exposure may accelerate aging processes, a comparative study now is being conducted on the pattern of age changes in electrocardiographic findings for the exposed and controls. In this report, emphasis is placed on the method of formulation of this study for statistical analysis. Two aspects of aging are considered: The frequency of abnormal electrocardiographic findings. Age changes found in normal electrocardiographic tracings. The first problem is an analysis of a three dimensional cross table of prevalence of electrocardiographic abnormalities by age, exposure group and a third factor (for instance, a socioeconomic or physiological factor). In the analysis of the second problem, an aging index was established in order to analyse effectively age changes in the electrocardiographic tracings. After a study of 22 measurements, QRS axis, Q-T interval, R/sub II/, T/sub I/, SV/sub 1/, RV/sub 1/, and RV/sub 5/ amplitudes were selected and their combination was derived to attain the highest correlation with age. Preliminary analysis was conducted for males for whom data collection had been completed. In the results so far obtained, no statistically significant differences were noted between the exposure groups. However, further detailed analysis should be conducted on these data together with data for females which are now being compiled. 18 references, 4 figures, 5 tables.
High-resolution coupled physics solvers for analysing fine-scale nuclear reactor design problems
Mahadevan, Vijay S.; Merzari, Elia; Tautges, Timothy; Jain, Rajeev; Obabko, Aleksandr; Smith, Michael; Fischer, Paul
2014-01-01
An integrated multi-physics simulation capability for the design and analysis of current and future nuclear reactor models is being investigated, to tightly couple neutron transport and thermal-hydraulics physics under the SHARP framework. Over several years, high-fidelity, validated mono-physics solvers with proven scalability on petascale architectures have been developed independently. Based on a unified component-based architecture, these existing codes can be coupled with a mesh-data backplane and a flexible coupling-strategy-based driver suite to produce a viable tool for analysts. The goal of the SHARP framework is to perform fully resolved coupled physics analysis of a reactor on heterogeneous geometry, in order to reduce the overall numerical uncertainty while leveraging available computational resources. The coupling methodology and software interfaces of the framework are presented, along with verification studies on two representative fast sodium-cooled reactor demonstration problems to prove the usability of the SHARP framework. PMID:24982250
DeBonis, James R.
2013-01-01
A computational fluid dynamics code that solves the compressible Navier-Stokes equations was applied to the Taylor-Green vortex problem to examine the code s ability to accurately simulate the vortex decay and subsequent turbulence. The code, WRLES (Wave Resolving Large-Eddy Simulation), uses explicit central-differencing to compute the spatial derivatives and explicit Low Dispersion Runge-Kutta methods for the temporal discretization. The flow was first studied and characterized using Bogey & Bailley s 13-point dispersion relation preserving (DRP) scheme. The kinetic energy dissipation rate, computed both directly and from the enstrophy field, vorticity contours, and the energy spectra are examined. Results are in excellent agreement with a reference solution obtained using a spectral method and provide insight into computations of turbulent flows. In addition the following studies were performed: a comparison of 4th-, 8th-, 12th- and DRP spatial differencing schemes, the effect of the solution filtering on the results, the effect of large-eddy simulation sub-grid scale models, and the effect of high-order discretization of the viscous terms.
A Theory of Name Resolution with extended Coverage and Proofs
Neron, P.J.M.; Tolmach, A.P.; Visser, E.; Wachsmuth, G.
2015-01-01
We describe a language-independent theory for name binding and resolution, suitable for programming languages with complex scoping rules including both lexical scoping and modules. We formulate name resolution as a two stage problem. First a language-independent scope graph is constructed using
Energy Technology Data Exchange (ETDEWEB)
Bradonjic, Milan [Los Alamos National Laboratory
2009-01-01
In this paper we study reputation mechanisms, and show how the notion of reputation can help us in building truthful online auction mechanisms. From the mechanism design prospective, we derive the conditions on and design a truthful online auction mechanism. Moreover, in the case when some agents may lay or cannot have the real knowledge about the other agents reputations, we derive the resolution of the auction, such that the mechanism is truthful. Consequently, we move forward to the optimal one-gambler/one-seller problem, and explain how that problem is refinement of the previously discussed online auction design in the presence of reputation mechanism. In the setting of the optimal one-gambler problem, we naturally rise and solve the specific question: What is an agent's optimal strategy, in order to maximize his revenue? We would like to stress that our analysis goes beyond the scope, which game theory usually discusses under the notion of reputation. We model one-player games, by introducing a new parameter (reputation), which helps us in predicting the agent's behavior, in real-world situations, such as, behavior of a gambler, real-estate dealer, etc.
International Nuclear Information System (INIS)
Papoular, R.J.; Zheludev, A.; Ressouche, E.; Schweizer, J.
1995-01-01
When density distributions in crystals are reconstructed from 3D diffraction data, a problem sometimes occurs when the spatial resolution in one given direction is very small compared to that in perpendicular directions. In this case, a 2D projected density is usually reconstructed. For this task, the conventional Fourier inversion method only makes use of those structure factors measured in the projection plane. All the other structure factors contribute zero to the reconstruction of a projected density. On the contrary, the maximum-entropy method uses all the 3D data, to yield 3D-enhanced 2D projected density maps. It is even possible to reconstruct a projection in the extreme case when not one structure factor in the plane of projection is known. In the case of poor resolution along one given direction, a Fourier inversion reconstruction gives very low quality 3D densities 'smeared' in the third dimension. The application of the maximum-entropy procedure reduces the smearing significantly and reasonably well resolved projections along most directions can now be obtained from the MaxEnt 3D density. To illustrate these two ideas, particular examples based on real polarized neutron diffraction data sets are presented. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Caillet, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1961-07-01
The author reviews precisely the analogical techniques used for the resolution of the kinetic equations of nuclear reactors. Prior to this, he recalls the reasons which oblige physicians and engineers, even today, to use electronic machines in this domain. The author then considers the technological problems posed by the range of values which the various nuclear parameters adopt. In each case, he shows that a compromise is possible allowing an optimum precision. He compares the results to those obtained by arithmetic calculation and uses the examples chosen in a critical analysis of the present possibilities of the two methods of calculation. (author) [French] L'auteur cherche a faire un point aussi exact que possible des techniques analogiques utilisees pour resoudre les equations cinetiques des reacteurs nucleaires. Il rappelle auparavant les raisons pour lesquelles physiciens et ingenieurs sont obliges, encore aujourd'hui, de faire appel aux machines electroniques dans ce domaine. Puis il etudie les problemes technologiques que souleve le champ des valeurs prises par les differents parametres nucleaires. Dans chacun des cas, il montre l'existence d'un compromis qui permet d'atteindre une precision optimum. Il compare les resultats obtenus a ceux provenant de calculateurs arithmetiques et profite des exemples choisis pour faire une analyse critique des possibilites actuelles offertes par les deux modes de calcul. (auteur)
Ardalan, A.; Safari, A.; Grafarend, E.
2003-04-01
A new ellipsoidal gravimetric-satellite altimetry boundary value problem has been developed and successfully tested. This boundary value problem has been constructed for gravity observables of the type (i) gravity potential (ii) gravity intensity (iii) deflection of vertical and (iv) satellite altimetry data. The developed boundary value problem is enjoying the ellipsoidal nature and as such can take advantage of high precision GPS observations in the set-up of the problem. The highlights of the solution are as follows: begin{itemize} Application of ellipsoidal harmonic expansion up to degree/order and ellipsoidal centrifugal field for the reduction of global gravity and isostasy effects from the gravity observable at the surface of the Earth. Application of ellipsoidal Newton integral on the equal area map projection surface for the reduction of residual mass effects within a radius of 55 km around the computational point. Ellipsoidal harmonic downward continuation of the residual observables from the surface of the earth down to the surface of reference ellipsoid using the ellipsoidal height of the observation points derived from GPS. Restore of the removed effects at the application points on the surface of reference ellipsoid. Conversion of the satellite altimetry derived heights of the water bodies into potential. Combination of the downward continued gravity information with the potential equivalent of the satellite altimetry derived heights of the water bodies. Application of ellipsoidal Bruns formula for converting the potential values on the surface of the reference ellipsoid into the geoidal heights (i.e. ellipsoidal heights of the geoid) with respect to the reference ellipsoid. Computation of the high-resolution geoid of Iran has successfully tested this new methodology!
Directory of Open Access Journals (Sweden)
Marcin Krzeszowiec
2015-03-01
Full Text Available Computer simulations of physical phenomena are at the moment common both in science and industry. The possibility of finding approximate solutions for complicated systems of differential equations, mathematically describing issues in the fields of mechanics, physics or chemistry, allows for shorten design and research time, often significantly reducing the need for expensive experimental studies or costly production of prototypes. However, the mentioned prevalence of these methods, particularly the Finite Element Method, resulted in analysis outcomes to be often in advance regarded as accurate ones. The purpose of the article is to showcase, on a simple stress analysis problem, how parameters such as the density of the finite element mesh, finite element formulation or integration scheme significantly influence on the simulation results and how easy it is to end up with the results that do not hold any physical sense, despite the fact that all the basic assumptions of correct analysis (suitable boundary conditions, total system energy stored etc. have been met. The results of this study can serve as a warning against premature conclusion drawing from calculations carried out by means of FEM simulation.[b]Keywords[/b]: computational mechanics, finite element method, shell elements, numerical integration
Moed, Anat; Gershoff, Elizabeth T; Eisenberg, Nancy; Hofer, Claire; Losoya, Sandra; Spinrad, Tracy L; Liew, Jeffrey
2015-08-01
Although conflict is a normative part of parent-adolescent relationships, conflicts that are long or highly negative are likely to be detrimental to these relationships and to youths' development. In the present article, sequential analyses of data from 138 parent-adolescent dyads (adolescents' mean age was 13.44, SD = 1.16; 52 % girls, 79 % non-Hispanic White) were used to define conflicts as reciprocal exchanges of negative emotion observed while parents and adolescents were discussing "hot," conflictual issues. Dynamic components of these exchanges, including who started the conflicts, who ended them, and how long they lasted, were identified. Mediation analyses revealed that a high proportion of conflicts ended by adolescents was associated with longer conflicts, which in turn predicted perceptions of the "hot" issue as unresolved and adolescent behavior problems. The findings illustrate advantages of using sequential analysis to identify patterns of interactions and, with some certainty, obtain an estimate of the contingent relationship between a pattern of behavior and child and parental outcomes. These interaction patterns are discussed in terms of the roles that parents and children play when in conflict with each other, and the processes through which these roles affect conflict resolution and adolescents' behavior problems.
Camargo, Maria Beatriz Junqueira; Barros, Aluísio J D; Frazão, Paulo; Matijasevich, Alicia; Santos, Iná S; Peres, Marco Aurélio; Peres, Karen Glazer
2012-02-01
To estimate the prevalence of dental visits among preschool children and determine the factors associated with using dental services. A cross-sectional study was conducted with 1,129 five-year-old children from the Pelotas Birth Cohort Study in Pelotas (Southern Brazil) 2004, from September 2009 to January 2010. Use of dental services at least once in the child's life and the reason for the child's first dental visit were recorded. The categories assigned for the first dental visit were: routine check-up, resolution of a problem, or never saw a dentist. The oral examinations and interviews were performed in the children's homes. Socioeconomic aspects and independent variables related to the mother and child were analyzed using multivariable logistic regression. The prevalence of dental visits (both categories combined) was 37.0%. The main predictors for a routine visit were higher economic status, mothers with more schooling, and mothers who had received guidance about prevention. Major predictors for a visit because of a problem were having felt pain in the previous six months, mothers with higher education level, and mothers who had received guidance about prevention. Approximately 45.0% of mothers received information about how to prevent cavities, usually from the dentist. Children of mothers who adhered to health programs were more likely to have had a routine dental visit. The rate of preschool visits to dental services was lower than the rate for medical appointments (childcare). In addition to income and education, maternal behavior plays an important role in routine visits. Pain reported in the last six months and a high number of teeth affected by tooth decay, independent of other factors, were associated with visits for a specific problem. It is important to integrate oral health instruction into maternal and child health programs.
International Nuclear Information System (INIS)
Buckin, V
2012-01-01
The paper describes key aspects of interpretation of compressibility of solutes in liquid mixtures obtained through high-resolution measurements of ultrasonic parameters. It examines the fundamental relationships between the characteristics of solutes and the contributions of solutes to compressibility of liquid mixtures expressed through apparent adiabatic compressibility of solutes, and adiabatic compressibility of solute particles. In addition, it analyses relationships between the adiabatic compressibility of solutes and the measured ultrasonic characteristics of mixtures. Especial attention is given to the effects of solvents on the measured adiabatic compressibility of solutes and on concentration increment of ultrasonic velocity of solutes in mixtures.
International Nuclear Information System (INIS)
Theodorakis, M.C.; Simpson, D.R.; Leung, D.M.; Devous, M. Sr.
1983-01-01
A new method for monitoring tablet disintegration in vivo was developed. In this method, the tablets were labeled with a short-lived radionuclide, technetium 99m, and monitored by a gamma camera. Several innovations were introduced with this method. First, computer reconstruction algorithms were used to enhance the scintigraphic images of the disintegrating tablet in vivo. Second, the use of a four-pinhole collimator to acquire multiple views of the tablet resulted in high count rates and reduced acquisition times of the scintigraphic images. Third, the magnification of the scintigraphic images achieved by pinhole collimation led to significant improvement in resolution. Fourth, the radioinuclide was incorporated into the granulation so that the whole mass of the tablet was uniformly labeled with high levels of activity. This technique allowed the continuous monitoring of the disintegration process of tablets in vivo in experimental animals. Multiple pinhole collimation and the labeling process permitted the acquisition of quality scintigraphic images of the labeled tablet every 30 sec. The resolution of the method was tested in vitro and in vivo
Audits of radiopharmaceutical formulations
International Nuclear Information System (INIS)
Castronovo, F.P. Jr.
1992-01-01
A procedure for auditing radiopharmaceutical formulations is described. To meet FDA guidelines regarding the quality of radiopharmaceuticals, institutional radioactive drug research committees perform audits when such drugs are formulated away from an institutional pharmacy. All principal investigators who formulate drugs outside institutional pharmacies must pass these audits before they can obtain a radiopharmaceutical investigation permit. The audit team meets with the individual who performs the formulation at the site of drug preparation to verify that drug formulations meet identity, strength, quality, and purity standards; are uniform and reproducible; and are sterile and pyrogen free. This team must contain an expert knowledgeable in the preparation of radioactive drugs; a radiopharmacist is the most qualified person for this role. Problems that have been identified by audits include lack of sterility and apyrogenicity testing, formulations that are open to the laboratory environment, failure to use pharmaceutical-grade chemicals, inadequate quality control methods or records, inadequate training of the person preparing the drug, and improper unit dose preparation. Investigational radiopharmaceutical formulations, including nonradiolabeled drugs, must be audited before they are administered to humans. A properly trained pharmacist should be a member of the audit team
Corrales, Lia; Li, Haochuan; Heinz, Sebastian
2018-01-01
With accurate cross-sections and higher signal-to-noise, X-ray spectroscopy can directly measure Milky Way gas and dust-phase metal abundances with few underlying assumptions. The X-ray energy band is sensitive to absorption by all abundant interstellar metals — carbon, oxygen, neon, silicon, magnesium, and iron — whether they are in gas or dust form. High resolution X-ray spectra from Galactic X-ray point sources can be used to directly measure metal abundances from all phases of the interstellar medium (ISM) along singular sight lines. We show our progress for measuring the depth of photoelectric absorption edges from neutral ISM metals, using all the observations of bright Galactic X-ray binaries available in the Chandra HETG archive. The cross-sections we use take into account both the absorption and scattering effects by interstellar dust grains on the iron and silicate spectral features. However, there are many open problems for reconciling X-ray absorption spectroscopy with ISM observations in other wavelengths. We will review the state of the field, lab measurements needed, and ways in which the next generation of X-ray telescopes will contribute.
Energy Technology Data Exchange (ETDEWEB)
St. Germain, Shawn W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Farris, Ronald K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Whaley, April M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Medema, Heather D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gertman, David I. [Idaho National Lab. (INL), Idaho Falls, ID (United States)
2014-09-01
This research effort is a part of the Light-Water Reactor Sustainability (LWRS) Program, which is a research and development (R&D) program sponsored by Department of Energy (DOE) and performed in close collaboration with industry R&D programs that provide the technical foundations for licensing and managing the long-term, safe, and economical operation of current nuclear power plants. The LWRS program serves to help the U.S. nuclear industry adopt new technologies and engineering solutions that facilitate the continued safe operation of the plants and extension of the current operating licenses. The purpose of this research is to improve management of nuclear power plant (NPP) outages through the development of an advanced outage control center (AOCC) that is specifically designed to maximize the usefulness of communication and collaboration technologies for outage coordination and problem resolution activities. This technical report for industry implementation outlines methods and considerations for the establishment of an AOCC. This report provides a process for implementation of a change management plan, evaluation of current outage processes, the selection of technology, and guidance for the implementation of the selected technology. Methods are presented for both adoption of technologies within an existing OCC and for a complete OCC replacement, including human factors considerations for OCC design and setup.
MacKay, Rebecca A.; Smith, Stephen W.; Shah, Sandeep R.; Piascik, Robert S.
2005-01-01
The shuttle orbiter s reaction control system (RCS) primary thruster serial number 120 was found to contain cracks in the counter bores and relief radius after a chamber repair and rejuvenation was performed in April 2004. Relief radius cracking had been observed in the 1970s and 1980s in seven thrusters prior to flight; however, counter bore cracking had never been seen previously in RCS thrusters. Members of the Materials Super Problem Resolution Team (SPRT) of the NASA Engineering and Safety Center (NESC) conducted a detailed review of the relevant literature and of the documentation from the previous RCS thruster failure analyses. It was concluded that the previous failure analyses lacked sufficient documentation to support the conclusions that stress corrosion cracking or hot-salt cracking was the root cause of the thruster cracking and lacked reliable inspection controls to prevent cracked thrusters from entering the fleet. The NESC team identified and performed new materials characterization and mechanical tests. It was determined that the thruster intergranular cracking was due to hydrogen embrittlement and that the cracking was produced during manufacturing as a result of processing the thrusters with fluoride-containing acids. Testing and characterization demonstrated that appreciable environmental crack propagation does not occur after manufacturing.
International Nuclear Information System (INIS)
Zou, Ling; Zhao, Haihua; Zhang, Hongbin
2015-01-01
Highlights: • Using high-resolution spatial scheme in solving two-phase flow problems. • Fully implicit time integrations scheme. • Jacobian-free Newton–Krylov method. • Analytical solution for two-phase water faucet problem. - Abstract: The majority of the existing reactor system analysis codes were developed using low-order numerical schemes in both space and time. In many nuclear thermal–hydraulics applications, it is desirable to use higher-order numerical schemes to reduce numerical errors. High-resolution spatial discretization schemes provide high order spatial accuracy in smooth regions and capture sharp spatial discontinuity without nonphysical spatial oscillations. In this work, we adapted an existing high-resolution spatial discretization scheme on staggered grids in two-phase flow applications. Fully implicit time integration schemes were also implemented to reduce numerical errors from operator-splitting types of time integration schemes. The resulting nonlinear system has been successfully solved using the Jacobian-free Newton–Krylov (JFNK) method. The high-resolution spatial discretization and high-order fully implicit time integration numerical schemes were tested and numerically verified for several two-phase test problems, including a two-phase advection problem, a two-phase advection with phase appearance/disappearance problem, and the water faucet problem. Numerical results clearly demonstrated the advantages of using such high-resolution spatial and high-order temporal numerical schemes to significantly reduce numerical diffusion and therefore improve accuracy. Our study also demonstrated that the JFNK method is stable and robust in solving two-phase flow problems, even when phase appearance/disappearance exists
Energy Technology Data Exchange (ETDEWEB)
Zou, Ling; Zhao, Haihua; Zhang, Hongbin
2016-04-01
The phase appearance/disappearance issue presents serious numerical challenges in two-phase flow simulations. Many existing reactor safety analysis codes use different kinds of treatments for the phase appearance/disappearance problem. However, to our best knowledge, there are no fully satisfactory solutions. Additionally, the majority of the existing reactor system analysis codes were developed using low-order numerical schemes in both space and time. In many situations, it is desirable to use high-resolution spatial discretization and fully implicit time integration schemes to reduce numerical errors. In this work, we adapted a high-resolution spatial discretization scheme on staggered grid mesh and fully implicit time integration methods (such as BDF1 and BDF2) to solve the two-phase flow problems. The discretized nonlinear system was solved by the Jacobian-free Newton Krylov (JFNK) method, which does not require the derivation and implementation of analytical Jacobian matrix. These methods were tested with a few two-phase flow problems with phase appearance/disappearance phenomena considered, such as a linear advection problem, an oscillating manometer problem, and a sedimentation problem. The JFNK method demonstrated extremely robust and stable behaviors in solving the two-phase flow problems with phase appearance/disappearance. No special treatments such as water level tracking or void fraction limiting were used. High-resolution spatial discretization and second- order fully implicit method also demonstrated their capabilities in significantly reducing numerical errors.
Directory of Open Access Journals (Sweden)
K. Ioannidi
2014-01-01
Full Text Available We consider the problem of radiation from a vertical short (Hertzian dipole above flat lossy ground, which represents the well-known “Sommerfeld radiation problem” in the literature. The problem is formulated in a novel spectral domain approach, and by inverse three-dimensional Fourier transformation the expressions for the received electric and magnetic (EM field in the physical space are derived as one-dimensional integrals over the radial component of wavevector, in cylindrical coordinates. This formulation appears to have inherent advantages over the classical formulation by Sommerfeld, performed in the spatial domain, since it avoids the use of the so-called Hertz potential and its subsequent differentiation for the calculation of the received EM field. Subsequent use of the stationary phase method in the high frequency regime yields closed-form analytical solutions for the received EM field vectors, which coincide with the corresponding reflected EM field originating from the image point. In this way, we conclude that the so-called “space wave” in the literature represents the total solution of the Sommerfeld problem in the high frequency regime, in which case the surface wave can be ignored. Finally, numerical results are presented, in comparison with corresponding numerical results based on Norton’s solution of the problem.
Toot, Sandeep; Devine, Mike; Orrell, Martin
2011-12-01
To assess the effectiveness of crisis resolution/home treatment services for older people with mental health problems. A systematic review was conducted to report on the effectiveness of crisis resolution/home treatment teams (CRHTTs) for older people with mental health problems. As part of the review, we also carried out a scoping exercise to assess the typologies of older people's CRHTTs in practice, and to review these in the context of policy and research findings. The literature contains Grade C evidence, according to the Oxford Centre of Evidence Based Medicine (CEBM) guidelines, that CRHTTs are effective in reducing numbers of admissions to hospitals. Outcomes such as length of hospital stay and maintenance of community residence were reviewed but evidence was inadequate for drawing conclusions. The scoping exercise defined three types of home treatment service model: generic home treatment teams; specialist older adults home treatment teams; and intermediate care services. These home treatment teams seemed to be effectively managing crises and reducing admissions. This review has shown a lack of evidence for the efficacy of crisis resolution/home treatment teams in supporting older people with mental health problems to remain at home. There is clearly a need for a randomised controlled trial to establish the efficacy of crisis resolution/home treatment services for older people with mental health problems, as well as a more focussed assessment of the different home treatment service models which have developed in the UK. Copyright © 2011 John Wiley & Sons, Ltd.
Numerical convergence for a sewage disposal problem
Alvarez-Vázquez, L.J.; Martínez, A.; Rodríguez, C.; Vázquez-Méndez, M.E.
2001-01-01
The management of sewage disposal and the design of wastewater treatment systems can be formulated as a constrained pointwise optimal control problem. In this paper we study the convergence of the numerical resolution for the corresponding state system by means of a characteristics Galerkin method. The main difficulty of the problem is due to the existence of Radon measures in the right-hand side of the state system. Finally, we present numerical results for a realistic problem posed in a ria...
International Nuclear Information System (INIS)
Amouyal, A.; Tariel, H.
1966-01-01
Code name: January 1 st SCEA 011S. 2) Computer: IBM 7094; Programme system: Fortran II, 2 nd version. 3) Nature of the problem: resolution of cell problems with one space variable (planar, spherical and cylindrical geometries) and with one energy group, with isotropic sources in the double P n approximation (DP 1 and DP 3 approximation in planar and spherical geometries, DP 1 and DP 2 in cylindrical geometry). 4) Method used: the differential equations with limiting conditions are transformed into differential system with initial conditions which are integrated by a separate-step method. 5) Restrictions: number of physical media [fr
Byng, R.; Verhaak, P.; Jack, E.
2016-01-01
Background: Psychiatric diagnosis is the accepted basis for categorising mental health problems. The basis for classification of mental health problems is almost entirely nosological (based on symptoms/behaviours) rather than cause or underlying neurobiology. Diagnoses are known to be applied
Energy Technology Data Exchange (ETDEWEB)
Cartier, J
2006-04-15
This thesis focuses on mathematical analysis, numerical resolution and modelling of the transport equations. First of all, we deal with numerical approximation of the solution of the transport equations by using a mixed-hybrid scheme. We derive and study a mixed formulation of the transport equation, then we analyse the related variational problem and present the discretization and the main properties of the scheme. We particularly pay attention to the behavior of the scheme and we show its efficiency in the diffusion limit (when the mean free path is small in comparison with the characteristic length of the physical domain). We present academical benchmarks in order to compare our scheme with other methods in many physical configurations and validate our method on analytical test cases. Unstructured and very distorted meshes are used to validate our scheme. The second part of this thesis deals with two transport problems. The first one is devoted to the study of diffusion due to boundary conditions in a transport problem between two plane plates. The second one consists in modelling and simulating radiative transfer phenomenon in case of the industrial context of inertial confinement fusion. (author)
Energy Technology Data Exchange (ETDEWEB)
Cartier, J
2006-04-15
This thesis focuses on mathematical analysis, numerical resolution and modelling of the transport equations. First of all, we deal with numerical approximation of the solution of the transport equations by using a mixed-hybrid scheme. We derive and study a mixed formulation of the transport equation, then we analyse the related variational problem and present the discretization and the main properties of the scheme. We particularly pay attention to the behavior of the scheme and we show its efficiency in the diffusion limit (when the mean free path is small in comparison with the characteristic length of the physical domain). We present academical benchmarks in order to compare our scheme with other methods in many physical configurations and validate our method on analytical test cases. Unstructured and very distorted meshes are used to validate our scheme. The second part of this thesis deals with two transport problems. The first one is devoted to the study of diffusion due to boundary conditions in a transport problem between two plane plates. The second one consists in modelling and simulating radiative transfer phenomenon in case of the industrial context of inertial confinement fusion. (author)
Collins, Jeffery D.; Volakis, John L.; Jin, Jian-Ming
1990-01-01
A new technique is presented for computing the scattering by 2-D structures of arbitrary composition. The proposed solution approach combines the usual finite element method with the boundary-integral equation to formulate a discrete system. This is subsequently solved via the conjugate gradient (CG) algorithm. A particular characteristic of the method is the use of rectangular boundaries to enclose the scatterer. Several of the resulting boundary integrals are therefore convolutions and may be evaluated via the fast Fourier transform (FFT) in the implementation of the CG algorithm. The solution approach offers the principal advantage of having O(N) memory demand and employs a 1-D FFT versus a 2-D FFT as required with a traditional implementation of the CGFFT algorithm. The speed of the proposed solution method is compared with that of the traditional CGFFT algorithm, and results for rectangular bodies are given and shown to be in excellent agreement with the moment method.
Energy Technology Data Exchange (ETDEWEB)
Curbelo, Jesus P.; Silva, Odair P. da; Barros, Ricardo C. [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Instituto Politecnico. Programa de Pos-graduacao em Modelagem Computacional; Garcia, Carlos R., E-mail: cgh@instec.cu [Departamento de Ingenieria Nuclear, Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba)
2017-07-01
Presented here is the application of the adjoint technique for solving source-detector discrete ordinates (S{sub N}) transport problems by using a spectral nodal method. For slab-geometry adjoint S-N model, the adjoint spectral Green's function method (SGF{sup †}) is extended to multigroup problems considering arbitrary L'th-order of scattering anisotropy, and the possibility of non-zero prescribed boundary conditions for the forward S{sub N} transport problems. The SGF{sup †} method converges numerical solutions that are completely free from spatial truncation errors. In order to generate numerical solutions of the SGF{sup †} equations, we use the partial adjoint one-node block inversion (NBI) iterative scheme. Partial adjoint NBI scheme uses the most recent estimates for the node-edge adjoint angular Fluxes in the outgoing directions of a given discretization node, to solve the resulting adjoint SN problem in that node for all the adjoint angular fluxes in the incoming directions, which constitute the outgoing adjoint angular fluxes for the adjacent node in the sweeping directions. Numerical results are given to illustrate the present spectral nodal method features and some advantages of using the adjoint technique in source-detector problems. author)
International Nuclear Information System (INIS)
Curbelo, Jesus P.; Silva, Odair P. da; Barros, Ricardo C.
2017-01-01
Presented here is the application of the adjoint technique for solving source{detector discrete ordinates (S N ) transport problems by using a spectral nodal method. For slab-geometry adjoint S-N model, the adjoint spectral Green's function method (SGF † ) is extended to multigroup problems considering arbitrary L'th-order of scattering anisotropy, and the possibility of non{zero prescribed boundary conditions for the forward S N transport problems. The SGF † method converges numerical solutions that are completely free from spatial truncation errors. In order to generate numerical solutions of the SGF † equations, we use the partial adjoint one{node block inversion (NBI) iterative scheme. Partial adjoint NBI scheme uses the most recent estimates for the node-edge adjoint angular Fluxes in the outgoing directions of a given discretization node, to solve the resulting adjoint SN problem in that node for all the adjoint angular fluxes in the incoming directions, which constitute the outgoing adjoint angular fluxes for the adjacent node in the sweeping directions. Numerical results are given to illustrate the present spectral nodal method features and some advantages of using the adjoint technique in source-detector problems. author)
Energy Technology Data Exchange (ETDEWEB)
Schneider, K; Spangenberger, M [eds.
1986-01-01
Hardly any other topic has been the object of so much public discussion in recent years as the environment. A discussion, by the way, that is not infrequently governed by strong emotions, broadens into ideological controversy, and is characterized by lack of knowledge of the technical and economic dimensions of this theme. But technology and economy are not all that this, so controversial, topic of 'environment' encompasses. Increasingly, ethical and social questions are gaining importance and demonstrating the need for a comprehensive view of problems. At the same time one can neither deny the scope of a responsibility extending to future generations, nor must the attempt be dispensed with to view the problem complex in its relation to anthropology. The conference, organized by the 'Rheinisch-Westfaelisches Elektrizitaetswerk' (RWE) in cooperation with the Catholic Central Institute of Social Sciences and the Institute of German Economy, was to give insight into the concrete ecological problems associated with energy generation. By a direct approach, fields of experience were to be demonstrated and ecological measures presented. The concrete approach was to go along with theoretical reflection and the discussion of problem areas even including international aspects. The aim of this book is, on the one hand, to document the event, and on the other hand, to stimulate great interest in these questions also in future.
Energy Technology Data Exchange (ETDEWEB)
Curbelo, Jesus P.; Alves Filho, Hermes; Barros, Ricardo C., E-mail: jperez@iprj.uerj.br, E-mail: halves@iprj.uerj.br, E-mail: rcbarros@pq.cnpq.br [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Instituto Politecnico. Programa de Pos-Graduacao em Modelagem Computacional; Hernandez, Carlos R.G., E-mail: cgh@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba)
2015-07-01
The spectral Green's function (SGF) method is a numerical method that is free of spatial truncation errors for slab-geometry fixed-source discrete ordinates (S{sub N}) adjoint problems. The method is based on the standard spatially discretized adjoint S{sub N} balance equations and a nonstandard adjoint auxiliary equation expressing the node-average adjoint angular flux, in each discretization node, as a weighted combination of the node-edge outgoing adjoint fluxes. The auxiliary equation contains parameters which act as Green's functions for the cell-average adjoint angular flux. These parameters are determined by means of a spectral analysis which yields the local general solution of the S{sub N} equations within each node of the discretization grid. In this work a number of advances in the SGF adjoint method are presented: the method is extended to adjoint S{sub N} problems considering linearly anisotropic scattering and non-zero prescribed boundary conditions for the forward source-detector problem. Numerical results to typical model problems are considered to illustrate the efficiency and accuracy of the o offered method. (author)
Horkovics-Kovats, Stefan
2014-02-01
Dissolution profile of a finished dosage form (FDF) contains hidden information regarding the disintegration of the form and the particle properties of the active pharmaceutical ingredient. Here, an extraction of this information from the dissolution profile without limitation to sink conditions is provided. In the article, mathematical relationships between the continuously measured dissolution profile of an FDF containing uniform or heterogeneous particles and its disintegration rate are developed. Further, the determinability of the disintegration kinetics and particle properties released from an FDF using the derived recurrent procedure was analyzed. On the basis of the theoretical data sets, it was demonstrated that the introduced analysis of dissolution profiles correctly identifies the disintegration rate of FDF containing multiple particle types. Furthermore, for known disintegration rates, the intrinsic lifetime of particles (time needed for total particle dissolution in infinite volume) released from the FDF and their relative amount can be determined. The extractable information from FDF dissolution time profiles can be utilized in designing of the formulation process, resulting in improved understanding of FDF properties, contributing thus to the implementation of quality by design in the FDF development. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.
Generic Entity Resolution in Relational Databases
Sidló, Csaba István
Entity Resolution (ER) covers the problem of identifying distinct representations of real-world entities in heterogeneous databases. We consider the generic formulation of ER problems (GER) with exact outcome. In practice, input data usually resides in relational databases and can grow to huge volumes. Yet, typical solutions described in the literature employ standalone memory resident algorithms. In this paper we utilize facilities of standard, unmodified relational database management systems (RDBMS) to enhance the efficiency of GER algorithms. We study and revise the problem formulation, and propose practical and efficient algorithms optimized for RDBMS external memory processing. We outline a real-world scenario and demonstrate the advantage of algorithms by performing experiments on insurance customer data.
Crystallization Formulation Lab
Federal Laboratory Consortium — The Crystallization Formulation Lab fills a critical need in the process development and optimization of current and new explosives and energetic formulations. The...
Energy Technology Data Exchange (ETDEWEB)
Haworth, R. [New England Univ., Armidale, NSW (Australia). Dept. of Geography; Heijnis, H. [Australian Inst. of Nuclear Science and Engineering, Lucas Heights, NSW (Australia)
1997-12-31
With a range in excess of 150 years under optimum conditions, lead-210 dating represents a valuable tool for studying recent human impacts on the environment, particularly the effects of European settlement in Australia. It is therefore also useful for establishing the start of the pre-European record in a sediment profile. Despite these advantages, there are some unresolved problems that prevent the full potential of an atmospherically-derived lead-210 profile being extended as far into the past as the activity signal allows. lead 210 has a half-life of 22.26 years, and a capacity to precipitate and be adsorbed by terrestrial material, particularly lake and marine sediments. This out-of-phase (or unsupported) lead-210 thus returns to a specific terrigenous location where it is added to the lead- 210 formed continuously in situ from the local radium-226 (equivalent to supported lead-210). Dating is based on the measurement of the decline of this unsupported lead-210 against the equilibrium ratio of in situ lead-210/radium-226. Paper no. 13; Extended abstract. 2 refs., 1 fig.
International Nuclear Information System (INIS)
Haworth, R.
1997-01-01
With a range in excess of 150 years under optimum conditions, lead-210 dating represents a valuable tool for studying recent human impacts on the environment, particularly the effects of European settlement in Australia. It is therefore also useful for establishing the start of the pre-European record in a sediment profile. Despite these advantages, there are some unresolved problems that prevent the full potential of an atmospherically-derived lead-210 profile being extended as far into the past as the activity signal allows. lead 210 has a half-life of 22.26 years, and a capacity to precipitate and be adsorbed by terrestrial material, particularly lake and marine sediments. This out-of-phase (or unsupported) lead-210 thus returns to a specific terrigenous location where it is added to the lead- 210 formed continuously in situ from the local radium-226 (equivalent to supported lead-210). Dating is based on the measurement of the decline of this unsupported lead-210 against the equilibrium ratio of in situ lead-210/radium-226
Bigler, Franz
2006-01-01
The scientific organizers of the symposium put much emphasis on the identification and definition of hazard and the potential consequences thereof and three full sessions with a total of 13 presentations encompassing a wide range of related themes were planned for this topic. Unfortunately, one talk had to be cancelled because of illness of the speaker (BM Khadi, India). Some presentations covered conceptual approaches for environmental risk assessment (ERA) of GM plants (problem formulation in the risk assessment framework, familiarity approach, tiered and methodological frameworks, non-target risk assessment) and the use of models in assessing invasiveness and weediness of GM plants. Other presentations highlighted the lessons learned for future ERA from case studies and commercialized GM crops, and from monitoring of unintended releases to the environment. When the moderators of the three sessions came together after the presentations to align their summaries, there was an obvious need to restructure the 12 presentations in a way that allowed for a consistent summarizing discussion. The following new organization of the 12 talks was chosen: (1) Concepts for problem formulation and non-target risk assessment, (2) Modeling as a tool for predicting invasiveness of GM plants, (3) Case-studies of ERA of large-scale release, (4) Lessons learned for ERA from a commercialized GM plant, (5) Monitoring of unintended release of Bt maize in Mexico. The new thematic structure facilitates a more in-depth discussion of the presentations related to a specific topic, and the conclusions to be drawn are thus more consistent. Each moderator agreed to take responsibility for summarizing one or more themes and to prepare the respective report.
Directory of Open Access Journals (Sweden)
Mrityunjoy Roy
2013-04-01
Full Text Available In this paper, a technique has been developed to determine the optimum mix of logistic service providers of a make-to-order (MTO supply chain. A serial MTO supply chain with different stages/ processes has been considered. For each stage different logistic service providers with different mean processing lead times, but same lead time variances are available. A realistic assumption that for each stage, the logistic service provider who charges more for his service consumes less processing lead time and vice-versa has been made in our study. Thus for each stage, for each service provider, a combination of cost and mean processing lead time is available. Using these combinations, for each stage, a polynomial curve, expressing cost of that stage as a function of mean processing lead time is fit. Cumulating all such expressions of cost for the different stages along with incorporation of suitable constraints arising out of timely delivery, results in the formulation of a constrained nonlinear cost optimization problem. On solving the problem using mathematica, optimum processing lead time for each stage is obtained. Using these optimum processing lead times and by employing a simple technique the optimum logistic service provider mix of the supply chain along with the corresponding total cost of processing is determined. Finally to examine the effect of changes in different parameters on the optimum total processing cost of the supply chain, sensitivity analysis has been carried out graphically.
Multiple excitation of supports - Part 1. Formulation
International Nuclear Information System (INIS)
Galeao, A.C.N.R.; Barbosa, H.J.C.
1980-12-01
The formulation and the solution of a simple specific problem of support movement are presented. The formulation is extended to the general case of infinitesimal elasticity where the approximated solutions are obtained by the variational formulation with spatial discretization by Finite Element Method. Finally, the present usual numerical techniques for the treatment of the resulting ordinary differential equations system are discused: Direct integration, Modal overlap, Spectral response. (E.G.) [pt
An exact approach for aggregated formulations
DEFF Research Database (Denmark)
Gamst, Mette; Spoorendonk, Simon; Røpke, Stefan
Aggregating formulations is a powerful approach for problems to take on tractable forms. Aggregation may lead to loss of information, i.e. the aggregated formulation may be an approximation of the original problem. In branch-and-bound context, aggregation can also complicate branching, e.g. when...... optimality cannot be guaranteed by branching on aggregated variables. We present a generic exact solution method to remedy the drawbacks of aggregation. It combines the original and aggregated formulations and applies Benders' decomposition. We apply the method to the Split Delivery Vehicle Routing Problem....
JUPITER PROJECT - MERGING INVERSE PROBLEM FORMULATION TECHNOLOGIES
The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project seeks to enhance and build on the technology and momentum behind two of the most popular sensitivity analysis, data assessment, calibration, and uncertainty analysis programs used in envi...
Formulations and algorithms for rich routing problems
Veenstra, Marjolein
2017-01-01
In the last years, the environment in which logistics service providers operate has become more complex due to several trends. The rise of e-commerce led to a rapid growth in the number of packages to deliver. Where home delivery used to be the standard option, we now see that different delivery
Hamiltonian formulation of anomaly free chiral bosons
International Nuclear Information System (INIS)
Abdalla, E.; Abdalla, M.C.B.; Devecchi, F.P.; Zadra, A.
1988-01-01
Starting out of an anomaly free Lagrangian formulation for chiral scalars, which a Wess-Zumino Term (to cancel the anomaly), we formulate the corresponding hamiltonian problem. Ther we use the (quantum) Siegel invariance to choose a particular, which turns out coincide with the obtained by Floreanini and Jackiw. (author) [pt
Dynamic psychiatry and the psychodynamic formulation
African Journals Online (AJOL)
processes and psychiatric disorders are biological, the range ... The formulation furthermore helps with the initial orientation towards the patient: it anticipates and predicts how the patient ..... contributed to problems with his sexual identity.
DEFF Research Database (Denmark)
Nasrollahi, Kamal; Moeslund, Thomas B.
2014-01-01
Super-resolution, the process of obtaining one or more high-resolution images from one or more low-resolution observations, has been a very attractive research topic over the last two decades. It has found practical applications in many real world problems in different fields, from satellite...
Duality in constrained location problems
DEFF Research Database (Denmark)
Juel, Henrik; Love, Robert F.
1987-01-01
The dual of a facility location problem with general norms, distance constraints, and linear constraints is formulated.......The dual of a facility location problem with general norms, distance constraints, and linear constraints is formulated....
Ordinal Regression Based Subpixel Shift Estimation for Video Super-Resolution
Directory of Open Access Journals (Sweden)
Petrovic Nemanja
2007-01-01
Full Text Available We present a supervised learning-based approach for subpixel motion estimation which is then used to perform video super-resolution. The novelty of this work is the formulation of the problem of subpixel motion estimation in a ranking framework. The ranking formulation is a variant of classification and regression formulation, in which the ordering present in class labels namely, the shift between patches is explicitly taken into account. Finally, we demonstrate the applicability of our approach on superresolving synthetically generated images with global subpixel shifts and enhancing real video frames by accounting for both local integer and subpixel shifts.
Inverse problems of geophysics
International Nuclear Information System (INIS)
Yanovskaya, T.B.
2003-07-01
This report gives an overview and the mathematical formulation of geophysical inverse problems. General principles of statistical estimation are explained. The maximum likelihood and least square fit methods, the Backus-Gilbert method and general approaches for solving inverse problems are discussed. General formulations of linearized inverse problems, singular value decomposition and properties of pseudo-inverse solutions are given
Cabrera, V E
2012-08-01
This study contributes to the research literature by providing a new formulation for the cow replacement problem, and it also contributes to the Extension deliverables by providing a user-friendly decision support system tool that would more likely be adopted and applied for practical decision making. The cow value, its related values of a new pregnancy and a pregnancy loss, and their associated replacement policies determine profitability in dairy farming. One objective of this study was to present a simple, interactive, dynamic, and robust formulation of the cow value and the replacement problem, including expectancy of the future production of the cow and the genetic gain of the replacement. The proven hypothesis of this study was that all the above requirements could be achieved by using a Markov chain algorithm. The Markov chain model allowed (1) calculation of a forward expected value of a studied cow and its replacement; (2) use of a single model (the Markov chain) to calculate both the replacement policies and the herd statistics; (3) use of a predefined, preestablished farm reproductive replacement policy; (4) inclusion of a farmer's assessment of the expected future performance of a cow; (5) inclusion of a farmer's assessment of genetic gain with a replacement; and (6) use of a simple spreadsheet or an online system to implement the decision support system. Results clearly demonstrated that the decision policies found with the Markov chain model were consistent with more complex dynamic programming models. The final user-friendly decision support tool is available at http://dairymgt.info/ → Tools → The Economic Value of a Dairy Cow. This tool calculates the cow value instantaneously and is highly interactive, dynamic, and robust. When a Wisconsin dairy farm was studied using the model, the solution policy called for replacing nonpregnant cows 11 mo after calving or months in milk (MIM) if in the first lactation and 9 MIM if in later lactations. The
Energy Technology Data Exchange (ETDEWEB)
Amouyal, A; Tariel, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1966-07-01
Code name: January 1{sup st} SCEA 011S. 2) Computer: IBM 7094; Programme system: Fortran II, 2{sup nd} version. 3) Nature of the problem: resolution of cell problems with one space variable (planar, spherical and cylindrical geometries) and with one energy group, with isotropic sources in the double P{sub n} approximation (DP 1 and DP 3 approximation in planar and spherical geometries, DP 1 and DP 2 in cylindrical geometry). 4) Method used: the differential equations with limiting conditions are transformed into differential system with initial conditions which are integrated by a separate-step method. 5) Restrictions: number of physical media < 100, number of geometrical regions < 100, number of points < 1000. 6) Physical approximations: limiting conditions for reflection, black body or grey body (restrictions for spherical and cylindrical geometries). The diffusion can include an isotropy term in cylindrical geometry, 2 terms in the other geometries. Taking into account of macroscopic data. 7) Duration: calculation time for a network of 100 points: planar and spherical geometry: double P 1 1 second, D P 3 = 4 seconds; cylindrical geometry: double P 1 2 seconds, D P 2 = 4 seconds. To these times should be added the 3 seconds required for the output. 8) State of the programme under production. (authors) [French] 1) Nom du Code: Janvier 1 SCEA 011S. 2) Calculateur: IBM 7094; Systeme de programmation: Fortran II version-2. 3) Nature du probleme: resolution des problemes de cellule a une variable d'espace (geometries plane, spherique et cylindrique) et un groupe d'energie, avec sources isotropes, dans l'approxirnation double P{sub n} (Approximations DP 1 et DP 3 en geometrie plane et spherique, approximations DP 1 et DP 2 en geometrie cylindrique). Methode employee: les equations differentielles avec conditions aux limites sont transformees en systemes differentiels avec conditions initiales que l'on integre par une methode a pas separes. 5) Restrictions: nombre de
Resolution function in neutron diffractometry
International Nuclear Information System (INIS)
Popa, N.
1987-01-01
The resolution function in the neutron diffractometry is defined, on base of generalizing the resolution formerly formulated for the double axis neutron spectrometer. A polemical discussion is raised concerning an approach to this function existent in literature. The actual approach is concretized for the DN-2 time-of-flight diffractometer installed at the IBR-2 reactor
Langevin formulation of quantum dynamics
International Nuclear Information System (INIS)
Roncadelli, M.
1989-03-01
We first show that nonrelativistic quantum mechanics formulated at imaginary-(h/2 π) can formally be viewed as the Fokker-Planck description of a frictionless brownian motion, which occurs (in general) in an absorbing medium. We next offer a new formulation of quantum mechanics, which is basically the Langevin treatment of this brownian motion. Explicitly, we derive a noise-average representation for the transition probability W(X'',t''|X',t'), in terms of the solutions to a Langevin equation with a Gaussian white-noise. Upon analytic continuation back to real-(h/2 π),W(X'',t''|X',t') becomes the propagator of the original Schroedinger equation. Our approach allows for a straightforward application to quantum dynamical problems of the mathematical techniques of classical stochastic processes. Moreover, computer simulations of quantum mechanical systems can be carried out by using numerical programs based on the Langevin dynamics. (author). 19 refs, 1 tab
International Nuclear Information System (INIS)
Silva, R.S.; Galeao, A.C.; Carmo, E.G.D. do
1989-07-01
In this paper a new finite element model is constructed combining an r- refinement scheme with the CCAU method. The new formulation gives better approximation for boundary and internal layers compared to the standard CCAU, without increasing computer codes. (author) [pt
Flow Formulations for Curriculum-based Course Timetabling
DEFF Research Database (Denmark)
Bagger, Niels-Christian Fink; Kristiansen, Simon; Sørensen, Matias
2017-01-01
lower bound on one data instance in the benchmark data set from the second international timetabling competition. Regarding upper bounds, the formulation based on the minimum cost flow problem performs better on average than other mixed integer programming approaches for the CTT.......In this paper we present two mixed-integer programming formulations for the Curriculum based Course Timetabling Problem (CTT). We show that the formulations contain underlying network structures by dividing the CTT into two separate models and then connect the two models using flow formulation...... techniques. The first mixed-integer programming formulation is based on an underlying minimum cost flow problem, which decreases the number of integer variables significantly and improves the performance compared to an intuitive mixed-integer programming formulation. The second formulation is based...
Reactive decontamination formulation
Giletto, Anthony [College Station, TX; White, William [College Station, TX; Cisar, Alan J [Cypress, TX; Hitchens, G Duncan [Bryan, TX; Fyffe, James [Bryan, TX
2003-05-27
The present invention provides a universal decontamination formulation and method for detoxifying chemical warfare agents (CWA's) and biological warfare agents (BWA's) without producing any toxic by-products, as well as, decontaminating surfaces that have come into contact with these agents. The formulation includes a sorbent material or gel, a peroxide source, a peroxide activator, and a compound containing a mixture of KHSO.sub.5, KHSO.sub.4 and K.sub.2 SO.sub.4. The formulation is self-decontaminating and once dried can easily be wiped from the surface being decontaminated. A method for decontaminating a surface exposed to chemical or biological agents is also disclosed.
Directory of Open Access Journals (Sweden)
Nursalam
2014-01-01
Full Text Available The research aims to determine how the social design of policy formulation in recovery after disasters and social conflicts. The method used in the study is a qualitative research design, data collection techniques through documentation and interviews with key informants. The recovery of the public life after reconstruction due to natural disasters and social conflicts demanding greater government attention to solve bersoalan arising through the formulation of programs oriented to local values. The importance of such a policy given that the public is the target to be met interests, and basically in their social life with values that serve as a guide in achieving a common goal. The Formulations recovery program based value is essentially a process of public policy formulation design also is social design process that relies on the dimension; (1 a value appreciation of relevant actors; (2 an orientation toward conflict resolution, problem solving, and change. The first dimension concerns an administrator's to listen to other voices, share in others experiences, and gain new knowledge. The second describes the administrator's orientation toward conflict resolution, problem solving, and change; the administrator's actions can range from proactive to reactive. Research indicates that, the experience of local government in the province of East Nusa Tenggara post-disaster and conflict should be a lesson for having successfully implemented local values-based formulation design in formulating regional development programs.
Planar multibody dynamics formulation, programming and applications
Nikravesh, Parviz E
2007-01-01
Introduction Multibody Mechanical Systems Types of Analyses Methods of Formulation Computer Programming Application Examples Unit System Remarks Preliminaries Reference Axes Scalars and Vectors Matrices Vector, Array, and Matrix Differentiation Equations and Expressions Remarks Problems Fundamentals of Kinematics A Particle Kinematics of a Rigid Body Definitions Remarks Problems Fundamentals of Dynamics Newton's Laws of Motion Dynamics of a Body Force Elements Applied Forces Reaction Force Remarks Problems Point-Coordinates: Kinematics Multipoint
Preparation of radiopharmaceutical formulations
International Nuclear Information System (INIS)
Simon, J.; Garlich, J.R.; Frank, R.K.; McMillan, K.
1998-01-01
Radiopharmaceutical formulations for complexes comprising at least one radionuclide complexed with a ligand, or its physiologically-acceptable salts thereof, especially 153 samarium-ethylenediaminetetramethylenephosphonic acid, which optionally contains a divalent metal ion, e.g. calcium, and is frozen, thawed, and then administered by injection. Alternatively, the radiopharmaceutical formulations must contain the divalent metal and are frozen only if the time before administration is sufficiently long to cause concern for radiolysis of the ligand. 2 figs., 9 tabs
Tariff formulation and equalization
International Nuclear Information System (INIS)
Svartsund, Trond
2003-01-01
The primary goal of the transmission tariff is to provide for socioeconomic use of the transmission grid. The present tariff structure is basically right. The responsibility for the formulation of the tariff resides with the local grid owner. This must take place in agreement with the current regulations which are passed by the authorities. The formulation must be adaptable to the local requirements. EBL (Norwegian Electricity Industry Association) is content with the current regulations
An exact approach for aggregated formulations
DEFF Research Database (Denmark)
Gamst, Mette; Spoorendonk, Simon
Aggregating formulations is a powerful approach for transforming problems into taking more tractable forms. Aggregated formulations can, though, have drawbacks: some information may get lost in the aggregation and { put in a branch-and-bound context { branching may become very di_cult and even....... The paper includes general considerations on types of problems for which the method is of particular interest. Furthermore, we prove the correctness of the procedure and consider how to include extensions such as cutting planes and advanced branching strategies....
Operations research problems statements and solutions
Poler, Raúl; Díaz-Madroñero, Manuel
2014-01-01
The objective of this book is to provide a valuable compendium of problems as a reference for undergraduate and graduate students, faculty, researchers and practitioners of operations research and management science. These problems can serve as a basis for the development or study of assignments and exams. Also, they can be useful as a guide for the first stage of the model formulation, i.e. the definition of a problem. The book is divided into 11 chapters that address the following topics: Linear programming, integer programming, non linear programming, network modeling, inventory theory, queue theory, tree decision, game theory, dynamic programming and markov processes. Readers are going to find a considerable number of statements of operations research applications for management decision-making. The solutions of these problems are provided in a concise way although all topics start with a more developed resolution. The proposed problems are based on the research experience of the authors in real-world com...
Hayden, H. Emily; Chiu, Ming Ming
2015-01-01
We explore development of elementary preservice teachers' reflective practices as they solved problems encountered while teaching in a reading clinic. Written reflections (N = 175) were collected across 8 weeks from 23 preservice teachers and analyzed to investigate relationships among problem exploration, teaching adaptations, and problem…
Granulated decontamination formulations
Tucker, Mark D.
2007-10-02
A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a sorbent additive, and water. A highly adsorbent sorbent additive (e.g., amorphous silica, sorbitol, mannitol, etc.) is used to "dry out" one or more liquid ingredients into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.
Conflict Prevention and Resolution Center (CPRC)
The Conflict Prevention and Resolution Center is EPA's primary resource for services and expertise in the areas of consensus-building, collaborative problem solving, alternative dispute resolution, and environmental collaboration and conflict resolution.
International Nuclear Information System (INIS)
Kucukboyaci, Vefa; Haghighat, Alireza
2001-01-01
We have developed new angular multigrid formulations, including the Simplified Angular Multigrid (SAM), Nested Iteration (NI), and V-Cycle schemes, that are compatible with the parallel environment and the adaptive differencing strategy of the PENTRAN three-dimensional parallel S N code. Using the Fourier analysis method for an infinite, homogenous medium, we have investigated the effectiveness of the V-Cycle scheme for different problem parameters including scattering ratio, spatial differencing weights, quadrature order, and mesh size. We have further investigated the effectiveness of the new schemes for practical shielding applications such as the Kobayashi benchmark problem and the boiling water reactor core shroud problem. In this paper, we summarize the angular V-Cycle scheme implemented in the PENTRAN code, the Fourier Analysis of the V-Cycle scheme, and results of convergence analysis of the V-Cycle scheme using different problem parameters. The theoretical analysis reveals that the V-Cycle scheme is effective for a large range of scattering ratios and is insensitive to mesh size. Besides the theoretical analysis, we have applied the new angular multigrid schemes to shielding problems. In comparison to the standard PCR formulation, combinations of the new angular multigrid schemes and PCR (e.g., SAM+V-Cycle+PCR) have proved to be very effective for scattering ratios in a range of 0.6 to 0.9. (authors)
Energy Technology Data Exchange (ETDEWEB)
Castaneda M, V. H.; Martinez B, M. R.; Solis S, L. O.; Castaneda M, R.; Leon P, A. A.; Hernandez P, C. F.; Espinoza G, J. G.; Ortiz R, J. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, 98000 Zacatecas, Zac. (Mexico); Mendez, R. [CIEMAT, Departamento de Metrologia de Radiaciones Ionizantes, Laboratorio de Patrones Neutronicos, Av. Complutense 22, 28040 Madrid (Spain); Gallego, E. [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, C. Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Sousa L, M. A. [Comision Nacional de Energia Nuclear, Centro de Investigacion de Tecnologia Nuclear, Av. Pte. Antonio Carlos 6627, Pampulha, 31270-901 Belo Horizonte, Minas Gerais (Brazil)
2016-10-15
The Taguchi methodology has proved to be highly efficient to solve inverse problems, in which the values of some parameters of the model must be obtained from the observed data. There are intrinsic mathematical characteristics that make a problem known as inverse. Inverse problems appear in many branches of science, engineering and mathematics. To solve this type of problem, researches have used different techniques. Recently, the use of techniques based on Artificial Intelligence technology is being explored by researches. This paper presents the use of a software tool based on artificial neural networks of generalized regression in the solution of inverse problems with application in high energy physics, specifically in the solution of the problem of neutron spectrometry. To solve this problem we use a software tool developed in the Mat Lab programming environment, which employs a friendly user interface, intuitive and easy to use for the user. This computational tool solves the inverse problem involved in the reconstruction of the neutron spectrum based on measurements made with a Bonner spheres spectrometric system. Introducing this information, the neural network is able to reconstruct the neutron spectrum with high performance and generalization capability. The tool allows that the end user does not require great training or technical knowledge in development and/or use of software, so it facilitates the use of the program for the resolution of inverse problems that are in several areas of knowledge. The techniques of Artificial Intelligence present singular veracity to solve inverse problems, given the characteristics of artificial neural networks and their network topology, therefore, the tool developed has been very useful, since the results generated by the Artificial Neural Network require few time in comparison to other techniques and are correct results comparing them with the actual data of the experiment. (Author)
Initial value formulation of higher derivative gravity
International Nuclear Information System (INIS)
Noakes, D.R.
1983-01-01
The initial value problem is considered for the conformally coupled scalar field and higher derivative gravity, by expressing the equations of each theory in harmonic coordinates. For each theory it is shown that the (vacuum) equations can take the form of a diagonal hyperbolic system with constraints on the initial data. Consequently these theories possess well-posed initial value formulations
On fictitious domain formulations for Maxwell's equations
DEFF Research Database (Denmark)
Dahmen, W.; Jensen, Torben Klint; Urban, K.
2003-01-01
We consider fictitious domain-Lagrange multiplier formulations for variational problems in the space H(curl: Omega) derived from Maxwell's equations. Boundary conditions and the divergence constraint are imposed weakly by using Lagrange multipliers. Both the time dependent and time harmonic formu...
Conflict Resolution for Contrasting Cultures.
Clarke, Clifford C.; Lipp, G. Douglas
1998-01-01
A seven-step process can help people from different cultures understand each other's intentions and perceptions so they can work together harmoniously: problem identification, problem clarification, cultural exploration, organizational exploration, conflict resolution, impact assessment, and organizational integration. (JOW)
Element free Galerkin formulation of composite beam with longitudinal slip
Energy Technology Data Exchange (ETDEWEB)
Ahmad, Dzulkarnain; Mokhtaram, Mokhtazul Haizad [Department of Civil Engineering, Universiti Selangor, Bestari Jaya, Selangor (Malaysia); Badli, Mohd Iqbal; Yassin, Airil Y. Mohd [Faculty of Civil Engineering, Universiti Teknologi Malaysia, Skudai, Johor (Malaysia)
2015-05-15
Behaviour between two materials in composite beam is assumed partially interact when longitudinal slip at its interfacial surfaces is considered. Commonly analysed by the mesh-based formulation, this study used meshless formulation known as Element Free Galerkin (EFG) method in the beam partial interaction analysis, numerically. As meshless formulation implies that the problem domain is discretised only by nodes, the EFG method is based on Moving Least Square (MLS) approach for shape functions formulation with its weak form is developed using variational method. The essential boundary conditions are enforced by Langrange multipliers. The proposed EFG formulation gives comparable results, after been verified by analytical solution, thus signify its application in partial interaction problems. Based on numerical test results, the Cubic Spline and Quartic Spline weight functions yield better accuracy for the EFG formulation, compares to other proposed weight functions.
Maxwell, Jacinta; Lowe, Kevin; Salter, Peta
2018-01-01
This paper focuses on the 'problem' of Aboriginal and Torres Strait Islander education represented in the Australian Curriculum's Aboriginal and Torres Strait Islander histories and cultures cross-curriculum priority. Looking beyond particular curriculum content, we uncover the policy discourses that construct (and reconstruct) the…
Policy formulation of public acceptance
International Nuclear Information System (INIS)
Kasai, Akihiro
1978-01-01
Since 1970, the new policy formulation for public acceptance of the new consideration on the location of electric power generation has been set and applied. The planning and the enforcement being conducted by local public organizations for the local economic build-up with plant location and also the adjustement of the requirements for fishery are two main specific characters in this new policy. The background of this new public acceptance policy, the history and the actual problems about the compensation for the location of power generation plants are reviewed. One new proposal, being recommended by the Policy and Science Laboratory to MITI in 1977 is explained. This is based on the method of promoting the location of power generation plants by public participation placing the redevelopment of regional societies as its basis. The problems concerning the industrial structures in farm villages, fishing villages and the areas of commerce and industry should be systematized, and explained from the viewpoint of outside impact, the characteristics of local areas and the location problems in this new proposal. Finally, the location process and its effectiveness should be put in order. (Nakai, Y.)
Formulation and stability testing of photolabile drugs.
Tønnesen, H H
2001-08-28
Exposure of a drug to irradiation can influence the stability of the formulation, leading to changes in the physicochemical properties of the product. The influence of excipients of frequently used stabilizers is often difficult to predict and, therefore, stability testing of the final preparation is important. The selection of a protective packaging must be based on knowledge about the wavelength causing the instability. Details on drug photoreactivity will also be helpful in order to minimize side-effects and/or optimize drug targeting by developing photoresponsive drug delivery systems. This review focuses on practical problems related to formulation and stability testing of photolabile drugs.
DEFF Research Database (Denmark)
Skovhus, Randi Boelskifte; Thomsen, Rie
2017-01-01
This article introduces a method to critical reviews and explores the ways in which problems have been formulated in knowledge production on career guidance in Denmark over a 10-year period from 2004 to 2014. The method draws upon the work of Bacchi focussing on the ‘What's the problem represented...... to be’ (WPR) approach. Forty-nine empirical studies on Danish youth career guidance were included in the study. An analysis of the issues in focus resulted in nine problem categories. One of these, ‘targeting’, is analysed using the WPR approach. Finally, the article concludes that the WPR approach...... provides a constructive basis for a critical analysis and discussion of the collective empirical knowledge production on career guidance, stimulating awareness of problems and potential solutions among the career guidance community....
Callejo, Maria Luz
1994-01-01
Reports, in French, an investigation on the use of graphic representations in problem-solving tasks of the type in Spanish Mathematical Olympiads. Analysis showed that the choice and interpretation of the first graphic representation played a decisive role in the discovery of the solution. (34 references) (Author/MKR)
International Nuclear Information System (INIS)
Kumar, N.
1984-07-01
Quantum first passage problem (QUIPP) is formulated and solved in terms of a constrained Feynman path integral. The related paradox of blocking of unitary evolution by continuous observation on the system implicit in QUIPP is briefly discussed. (author)
Classifying IS Project Problems
DEFF Research Database (Denmark)
Munk-Madsen, Andreas
2006-01-01
The literature contains many lists of IS project problems, often in the form of risk factors. The problems sometimes appear unordered and overlapping, which reduces their usefulness to practitioners as well as theoreticians. This paper proposes a list of criteria for formulating project problems...
Chen, X.; Abercrombie, R. E.; Pennington, C.
2017-12-01
Recorded seismic waveforms include contributions from earthquake source properties and propagation effects, leading to long-standing trade-off problems between site/path effects and source effects. With near-field recordings, the path effect is relatively small, so the trade-off problem can be simplified to between source and site effects (commonly referred as "kappa value"). This problem is especially significant for small earthquakes where the corner frequencies are within similar ranges of kappa values, so direct spectrum fitting often leads to systematic biases due to corner frequency and magnitude. In response to the significantly increased seismicity rate in Oklahoma, several local networks have been deployed following major earthquakes: the Prague, Pawnee and Fairview earthquakes. Each network provides dense observations within 20 km surrounding the fault zone, recording tens of thousands of aftershocks between M1 to M3. Using near-field recordings in the Prague area, we apply a stacking approach to separate path/site and source effects. The resulting source parameters are consistent with parameters derived from ground motion and spectral ratio methods from other studies; they exhibit spatial coherence within the fault zone for different fault patches. We apply these source parameter constraints in an analysis of kappa values for stations within 20 km of the fault zone. The resulting kappa values show significantly reduced variability compared to those from direct spectral fitting without constraints on the source spectrum; they are not biased by earthquake magnitudes. With these improvements, we plan to apply the stacking analysis to other local arrays to analyze source properties and site characteristics. For selected individual earthquakes, we will also use individual-pair empirical Green's function (EGF) analysis to validate the source parameter estimations.
Directory of Open Access Journals (Sweden)
Igor V. Karyakin
2017-01-01
Full Text Available From 19 to 24 September, 2016 VII International Conference of the Working Group on Raptors of Northern Eurasia “Birds of prey of Northern Eurasia: problems and adaptation under modern conditions” was held on the basis of the Sochi National Park. Materials for the conference were presented by 198 ornithologists from Russia, Ukraine, Belarus, Kazakhstan, Moldova, Turkmenistan, Austria, Great Britain, Hungary, Mongolia, Poland, Estonia and the USA, who published 148 articles in two collections “Birds of prey of Northern Eurasia” and “Palearctic Harriers”.
Systematic Equation Formulation
DEFF Research Database (Denmark)
Lindberg, Erik
2007-01-01
A tutorial giving a very simple introduction to the set-up of the equations used as a model for an electrical/electronic circuit. The aim is to find a method which is as simple and general as possible with respect to implementation in a computer program. The “Modified Nodal Approach”, MNA, and th......, and the “Controlled Source Approach”, CSA, for systematic equation formulation are investigated. It is suggested that the kernel of the P Spice program based on MNA is reprogrammed....
Empathy deficit in antisocial personality disorder: a psychodynamic formulation.
Malancharuvil, Joseph M
2012-09-01
Empathic difficulty is a highly consequential characteristic of antisocial personality structure. The origin, maintenance, and possible resolution of this profound deficit are not very clear. While reconstructing empathic ability is of primary importance in the treatment of antisocial personality, not many proven procedures are in evidence. In this article, the author offers a psychodynamic formulation of the origin, character, and maintenance of the empathic deficiency in antisocial personality. The author discusses some of the treatment implications from this dynamic formulation.
Drug delivery and formulations.
Breitkreutz, Jörg; Boos, Joachim
2011-01-01
Paediatric drug delivery is a major challenge in drug development. Because of the heterogeneous nature of the patient group, ranging from newborns to adolescents, there is a need to use appropriate excipients, drug dosage forms and delivery devices for different age groups. So far, there is a lack of suitable and safe drug formulations for children, especially for the very young and seriously ill patients. The new EU legislation will enforce paediatric clinical trials and drug development. Current advances in paediatric drug delivery include interesting new concepts such as fast-dissolving drug formulations, including orodispersible tablets and oral thin strips (buccal wafers), and multiparticulate dosage forms based on mini-tabletting or pelletization technologies. Parenteral administration is likely to remain the first choice for children in the neonatal period and for emergency cases. Alternative routes of administration include transdermal, pulmonary and nasal drug delivery systems. A few products are already available on the market, but others still need further investigations and clinical proof of concept.
Ether formulations of relativity
International Nuclear Information System (INIS)
Duffy, M.C.
1980-01-01
Contemporary ether theories are surveyed and criticised, especially those formally identical to orthodox Relativity. The historical development of Relativity, Special and General, in terms of an ether, is briefly indicated. Classical interpretations of Generalized Relativity using ether are compared to Euclidean formulations using a background space. The history of a sub-group of theories, formulating a 'new' Relativity involving modified transforms, is outlined. According to the theory with which they agree, recent supposed detections of drift are classified and criticised. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticised as being contrary to the positivist spirit. The history of mechanical analogues is traced, from Hartley's representing gravitating matter as spherical standing waves, to recent suggestions that vortex-sponge might model electromagnetic, quantum, uncertainty and faster-than-light phenomena. Contemporary theories are particular physical theories, themselves 'second interpretations' of a primary mathematical model. Mechanical analogues are auxiliary, not necessary, to other theory, disclosing relationships between classical and non-classical descriptions of assemblies charging state. The ether-relativity polemic, part of a broader dispute about relativity, is founded on mistaken conceptions of the roles of mathematical and physical models, mechanical analogues; and a distored view of history, which indicates that ether theories have become relativistic. (author)
DEFF Research Database (Denmark)
Harrod, Steven; Schlechte, Thomas
2013-01-01
Two fundamental mathematical formulations for railway timetabling are compared on a common set of sample problems, representing both multiple track high density services in Europe and single track bidirectional operations in North America. One formulation, ACP, enforces against conflicts by const......Two fundamental mathematical formulations for railway timetabling are compared on a common set of sample problems, representing both multiple track high density services in Europe and single track bidirectional operations in North America. One formulation, ACP, enforces against conflicts...
Simultaneously Exploiting Two Formulations: an Exact Benders Decomposition Approach
DEFF Research Database (Denmark)
Lusby, Richard Martin; Gamst, Mette; Spoorendonk, Simon
When modelling a given problem using linear programming techniques several possibilities often exist, and each results in a different mathematical formulation of the problem. Usually, advantages and disadvantages can be identified in any single formulation. In this paper we consider mixed integer...... to the standard branch-and-price approach from the literature, the method shows promising performance and appears to be an attractive alternative....
Zbožínek, Adam
2009-01-01
Tato práce uvádí základní pravidla a předpoklady pro konstrukci a použití vozů formule 1. Hlavní zaměření je na aerodynamiku, která je nejdůležitější disciplínou v tomto motoristickém sportu, dále je tato práce zaměřena na základní faktory týkající se motoru vozu, kol, nové technologie KERS a provedení volantu. This work shows basic rules and conditions for construction and use of cars formula 1. The main part of this work focus on the aerodynamics which is the most important discipline of...
Assessment of strategy formulation
DEFF Research Database (Denmark)
Acur, Nuran; Englyst, Linda
2006-01-01
of the success criteria through face-to-face interviews with 46 managers, workshops involving 40 managers, and two in-depth case studies. The success criteria have been slightly modified due to the empirical results, to yield the assessment tool. Findings – The resulting assessment tool integrates three generic...... approaches to strategy assessment, namely the goal-centred, comparative and improvement approaches, as found in the literature. Furthermore, it encompasses three phases of strategy formulation processes: strategic thinking, strategic planning and embedding of strategy. The tool reflects that the different......, but cases and managerial perceptions indicate that the need for accurate and detailed plans might be overrated in the literature, as implementation relies heavily on continuous improvement and empowerment. Concerning embedding, key aspects relate both to the goal-centred and improvement approaches, while...
High resolution solar observations
International Nuclear Information System (INIS)
Title, A.
1985-01-01
Currently there is a world-wide effort to develop optical technology required for large diffraction limited telescopes that must operate with high optical fluxes. These developments can be used to significantly improve high resolution solar telescopes both on the ground and in space. When looking at the problem of high resolution observations it is essential to keep in mind that a diffraction limited telescope is an interferometer. Even a 30 cm aperture telescope, which is small for high resolution observations, is a big interferometer. Meter class and above diffraction limited telescopes can be expected to be very unforgiving of inattention to details. Unfortunately, even when an earth based telescope has perfect optics there are still problems with the quality of its optical path. The optical path includes not only the interior of the telescope, but also the immediate interface between the telescope and the atmosphere, and finally the atmosphere itself
High resolution drift chambers
International Nuclear Information System (INIS)
Va'vra, J.
1985-07-01
High precision drift chambers capable of achieving less than or equal to 50 μm resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs
Complex Sequencing Problems and Local Search Heuristics
Brucker, P.; Hurink, Johann L.; Osman, I.H.; Kelly, J.P.
1996-01-01
Many problems can be formulated as complex sequencing problems. We will present problems in flexible manufacturing that have such a formulation and apply local search methods like iterative improvement, simulated annealing and tabu search to solve these problems. Computational results are reported.
Development of formulation device for periodontal disease.
Sato, Yasuhiko; Oba, Takuma; Watanabe, Norio; Danjo, Kazumi
2012-01-01
In addition to providing standard surgical treatment that removes the plaque and infected tissues, medications that can regenerate periodontal tissue are also required in the treatment of periodontal disease. As a form of regenerative medication, various growth factors are expected to be used while treating periodontal disease. A protein-like growth factor is often developed as a lyophilized product with dissolution liquid, considering its instability in the solution state. We have clarified that the formulation for periodontal disease needs to be viscous. When the lyophilized product was dissolved using a sticky solution, various problems were encountered, difficulty in dissolving and air bubbles, for example, and some efforts were needed to prepare the formulation. In this research, to identify the problem of preparing a viscous formulation, a lyophilized product (placebo) and sticky liquid were prepared by using vial and ampoule as the conventional containers. Based on these problems, a prototype administration device was developed, and its functionality was confirmed. As a result, it was suggested that the device with a useful mixing system that could shorten the preparation time was developed.
Directory of Open Access Journals (Sweden)
J.-I. Yano
2012-11-01
Full Text Available A generalized mass-flux formulation is presented, which no longer takes a limit of vanishing fractional areas for subgrid-scale components. The presented formulation is applicable to a~situation in which the scale separation is still satisfied, but fractional areas occupied by individual subgrid-scale components are no longer small. A self-consistent formulation is presented by generalizing the mass-flux formulation under the segmentally-constant approximation (SCA to the grid–scale variabilities. The present formulation is expected to alleviate problems arising from increasing resolutions of operational forecast models without invoking more extensive overhaul of parameterizations.
The present formulation leads to an analogy of the large-scale atmospheric flow with multi-component flows. This analogy allows a generality of including any subgrid-scale variability into the mass-flux parameterization under SCA. Those include stratiform clouds as well as cold pools in the boundary layer.
An important finding under the present formulation is that the subgrid-scale quantities are advected by the large-scale velocities characteristic of given subgrid-scale components (large-scale subcomponent flows, rather than by the total large-scale flows as simply defined by grid-box average. In this manner, each subgrid-scale component behaves as if like a component of multi-component flows. This formulation, as a result, ensures the lateral interaction of subgrid-scale variability crossing the grid boxes, which are missing in the current parameterizations based on vertical one-dimensional models, and leading to a reduction of the grid-size dependencies in its performance. It is shown that the large-scale subcomponent flows are driven by large-scale subcomponent pressure gradients. The formulation, as a result, furthermore includes a self-contained description of subgrid-scale momentum transport.
The main purpose of the present paper
Chudnovsky, A.; Dolgopolsky, A.; Kachanov, M.
1987-01-01
The elastic interactions of a two-dimensional configuration consisting of a crack with an array of microcracks located near the tip are studied. The general form of the solution is based on the potential representations and approximations of tractions on the microcracks by polynomials. In the second part, the technique is applied to two simple two-dimensional configurations involving one and two microcracks. The problems of stress shielding and stress amplification (the reduction or increase of the effective stress intensity factor due to the presence of microcracks) are discussed, and the refinements introduced by higher order polynomial approximations are illustrated.
International Nuclear Information System (INIS)
2003-05-01
To put a resolution to the meeting in relation with the use of weapons made of depleted uranium is the purpose of this text. The situation of the use of depleted uranium by France during the Gulf war and other recent conflicts will be established. This resolution will give the most strict recommendations face to the eventual sanitary and environmental risks in the use of these kind of weapons. (N.C.)
Baseline LAW Glass Formulation Testing
International Nuclear Information System (INIS)
Kruger, Albert A.; Mooers, Cavin; Bazemore, Gina; Pegg, Ian L.; Hight, Kenneth; Lai, Shan Tao; Buechele, Andrew; Rielley, Elizabeth; Gan, Hao; Muller, Isabelle S.; Cecil, Richard
2013-01-01
The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements
Lagrangian formulation of classical BMT-theory
International Nuclear Information System (INIS)
Pupasov-Maksimov, Andrey; Deriglazov, Alexei; Guzman, Walberto
2013-01-01
Full text: The most popular classical theory of electron has been formulated by Bargmann, Michel and Telegdi (BMT) in 1959. The BMT equations give classical relativistic description of a charged particle with spin and anomalous magnetic momentum moving in homogeneous electro-magnetic field. This allows to study spin dynamics of polarized beams in uniform fields. In particular, first experimental measurements of muon anomalous magnetic momentum were done using changing of helicity predicted by BMT equations. Surprisingly enough, a systematic formulation and the analysis of the BMT theory are absent in literature. In the present work we particularly fill this gap by deducing Lagrangian formulation (variational problem) for BMT equations. Various equivalent forms of Lagrangian will be discussed in details. An advantage of the obtained classical model is that the Lagrangian action describes a relativistic spinning particle without Grassmann variables, for both free and interacting cases. This implies also the possibility of canonical quantization. In the interacting case, an arbitrary electromagnetic background may be considered, which generalizes the BMT theory formulated to the case of homogeneous fields. The classical model has two local symmetries, which gives an interesting example of constrained classical dynamics. It is surprising, that the case of vanishing anomalous part of the magnetic momentum is naturally highlighted in our construction. (author)
Robust isotropic super-resolution by maximizing a Laplace posterior for MRI volumes
Han, Xian-Hua; Iwamoto, Yutaro; Shiino, Akihiko; Chen, Yen-Wei
2014-03-01
Magnetic resonance imaging can only acquire volume data with finite resolution due to various factors. In particular, the resolution in one direction (such as the slice direction) is much lower than others (such as the in-plane direction), yielding un-realistic visualizations. This study explores to reconstruct MRI isotropic resolution volumes from three orthogonal scans. This proposed super- resolution reconstruction is formulated as a maximum a posterior (MAP) problem, which relies on the generation model of the acquired scans from the unknown high-resolution volumes. Generally, the deviation ensemble of the reconstructed high-resolution (HR) volume from the available LR ones in the MAP is represented as a Gaussian distribution, which usually results in some noise and artifacts in the reconstructed HR volume. Therefore, this paper investigates a robust super-resolution by formulating the deviation set as a Laplace distribution, which assumes sparsity in the deviation ensemble based on the possible insight of the appeared large values only around some unexpected regions. In addition, in order to achieve reliable HR MRI volume, we integrates the priors such as bilateral total variation (BTV) and non-local mean (NLM) into the proposed MAP framework for suppressing artifacts and enriching visual detail. We validate the proposed robust SR strategy using MRI mouse data with high-definition resolution in two direction and low-resolution in one direction, which are imaged in three orthogonal scans: axial, coronal and sagittal planes. Experiments verifies that the proposed strategy can achieve much better HR MRI volumes than the conventional MAP method even with very high-magnification factor: 10.
"Planar" Tautologies Hard for Resolution
DEFF Research Database (Denmark)
Dantchev, Stefan; Riis, Søren
2001-01-01
We prove exponential lower bounds on the resolution proofs of some tautologies, based on rectangular grid graphs. More specifically, we show a 2Ω(n) lower bound for any resolution proof of the mutilated chessboard problem on a 2n×2n chessboard as well as for the Tseitin tautology (G. Tseitin, 196...
Generalized variational formulations for extended exponentially fractional integral
Directory of Open Access Journals (Sweden)
Zuo-Jun Wang
2016-01-01
Full Text Available Recently, the fractional variational principles as well as their applications yield a special attention. For a fractional variational problem based on different types of fractional integral and derivatives operators, corresponding fractional Lagrangian and Hamiltonian formulation and relevant Euler–Lagrange type equations are already presented by scholars. The formulations of fractional variational principles still can be developed more. We make an attempt to generalize the formulations for fractional variational principles. As a result we obtain generalized and complementary fractional variational formulations for extended exponentially fractional integral for example and corresponding Euler–Lagrange equations. Two illustrative examples are presented. It is observed that the formulations are in exact agreement with the Euler–Lagrange equations.
Single-particle Schroedinger fluid. I. Formulation
International Nuclear Information System (INIS)
Kan, K.K.; Griffin, J.J.
1976-01-01
The problem of a single quantal particle moving in a time-dependent external potential well is formulated specifically to emphasize and develop the fluid dynamical aspects of the matter flow. This idealized problem, the single-particle Schroedinger fluid, is shown to exhibit already a remarkably rich variety of fluid dynamical features, including compressible flow and line vortices. It provides also a sufficient framework to encompass simultaneously various simplified fluidic models for nuclei which have earlier been postulated on an ad hoc basis, and to illuminate their underlying restrictions. Explicit solutions of the single-particle Schroedinger fluid problem are studied in the adiabatic limit for their mathematical and physical implications (especially regarding the collective kinetic energy). The basic generalizations for extension of the treatment to the many-body Schroedinger fluid are set forth
Pitchaiah, Gummalla; Akula, Annapurna; Chandi, Vishala
2017-01-01
Background: Nutraceuticals help in combating some of the major health problems of the century including cancer, and ?nutraceutical formulations? have led to the new era of medicine and health. Objective: To develop different nutraceutical formulations and to assess the anticancer potential of nutraceutical formulations in N-methyl-N-nitrosourea (MNU)-induced mammary cancer in Sprague Dawley rats. Materials and Methods: Different nutraceutical formulations were prepared using fine powders of a...
Petrov-Galerkin mixed formulations for bidimensional elasticity
International Nuclear Information System (INIS)
Toledo, E.M.; Loula, A.F.D.; Guerreiro, J.N.C.
1989-10-01
A new formulation for two-dimensional elasticity in stress and displacements is presented. Consistently adding to the Galerkin classical formulation residuals forms of constitutive and equilibrium equations, the original saddle point is transformed into a minimization problem without any restrictions. We also propose a stress post processing technique using both equilibrium and constitutive equations. Numerical analysis error estimates and numerical results are presented confirming the predicted rates of convergence. (A.C.A.S.) [pt
Static and kinematic formulation of planar reciprocal assemblies
DEFF Research Database (Denmark)
Parigi, Dario; Sassone, Mario; Kirkegaard, Poul Henning
2014-01-01
Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed extending the theory of pin-jointed assemblies....... This formulation is used to evaluate the static and kinematic determinacy of reciprocal assemblies from the properties of their equilibrium and kinematic matrices...
Novel Formulations for Antimicrobial Peptides
Directory of Open Access Journals (Sweden)
Ana Maria Carmona-Ribeiro
2014-10-01
Full Text Available Peptides in general hold much promise as a major ingredient in novel supramolecular assemblies. They may become essential in vaccine design, antimicrobial chemotherapy, cancer immunotherapy, food preservation, organs transplants, design of novel materials for dentistry, formulations against diabetes and other important strategical applications. This review discusses how novel formulations may improve the therapeutic index of antimicrobial peptides by protecting their activity and improving their bioavailability. The diversity of novel formulations using lipids, liposomes, nanoparticles, polymers, micelles, etc., within the limits of nanotechnology may also provide novel applications going beyond antimicrobial chemotherapy.
Novel Formulations for Antimicrobial Peptides
Carmona-Ribeiro, Ana Maria; Carrasco, Letícia Dias de Melo
2014-01-01
Peptides in general hold much promise as a major ingredient in novel supramolecular assemblies. They may become essential in vaccine design, antimicrobial chemotherapy, cancer immunotherapy, food preservation, organs transplants, design of novel materials for dentistry, formulations against diabetes and other important strategical applications. This review discusses how novel formulations may improve the therapeutic index of antimicrobial peptides by protecting their activity and improving their bioavailability. The diversity of novel formulations using lipids, liposomes, nanoparticles, polymers, micelles, etc., within the limits of nanotechnology may also provide novel applications going beyond antimicrobial chemotherapy. PMID:25302615
Islamic Education Research Problem
Directory of Open Access Journals (Sweden)
Abdul Muthalib
2012-04-01
Full Text Available This paper will discuss Islamic educational studies that is reviewing how to find, limit and define problems and problem-solving concepts. The central question of this paper is to describe how to solve the problem in Islamic educational research. A researcher or educator who has the knowledge, expertise, or special interest on education for example is usually having a sensitivity to issues relating to educational research. In the research dimension of religious education, there are three types of problems, namely: Problems foundation, structural problems and operational issues. In doing research in Islamic education someone should understand research problem, limiting and formulating the problem, how to solve the problem, other problem relating to the point of research, and research approach.
Statistical formulation of gravitational radiation reaction
International Nuclear Information System (INIS)
Schutz, B.F.
1980-01-01
A new formulation of the radiation-reaction problem is proposed, which is simpler than alternatives which have been used before. The new approach is based on the initial-value problem, uses approximations which need be uniformly valid only in compact regions of space-time, and makes no time-asymmetric assumptions (no a priori introduction of retarded potentials or outgoing-wave asymptotic conditions). It defines radiation reaction to be the expected evolution of a source obtained by averaging over a statistical ensemble of initial conditions. The ensemble is chosen to reflect one's complete lack of information (in real systems) about the initial data for the radiation field. The approach is applied to the simple case of a weak-field, slow-motion source in general relativity, where it yields the usual expressions for radiation reaction when the gauge is chosen properly. There is a discussion of gauge freedom, and another of the necessity of taking into account reaction corrections to the particle-conservation equation. The analogy with the second law of thermodynamics is very close, and suggests that the electromagnetic and thermodynamic arrows of time are the same. Because the formulation is based on the usual initial-value problem, it has no spurious ''runaway'' solutions
Entity resolution for uncertain data
Ayat, N.; Akbarinia, R.; Afsarmanesh, H.; Valduriez, P.
2012-01-01
Entity resolution (ER), also known as duplicate detection or record matching, is the problem of identifying the tuples that represent the same real world entity. In this paper, we address the problem of ER for uncertain data, which we call ERUD. We propose two different approaches for the ERUD
Generic Mathematical Programming Formulation and Solution for Computer-Aided Molecular Design
DEFF Research Database (Denmark)
Zhang, Lei; Cignitti, Stefano; Gani, Rafiqul
2015-01-01
This short communication presents a generic mathematical programming formulation for Computer-Aided Molecular Design (CAMD). A given CAMD problem, based on target properties, is formulated as a Mixed Integer Linear/Non-Linear Program (MILP/MINLP). The mathematical programming model presented here......, which is formulated as an MILP/MINLP problem, considers first-order and second-order molecular groups for molecular structure representation and property estimation. It is shown that various CAMD problems can be formulated and solved through this model....
Neonates need tailored drug formulations.
Allegaert, Karel
2013-02-08
Drugs are very strong tools used to improve outcome in neonates. Despite this fact and in contrast to tailored perfusion equipment, incubators or ventilators for neonates, we still commonly use drug formulations initially developed for adults. We would like to make the point that drug formulations given to neonates need to be tailored for this age group. Besides the obvious need to search for active compounds that take the pathophysiology of the newborn into account, this includes the dosage and formulation. The dosage or concentration should facilitate the administration of low amounts and be flexible since clearance is lower in neonates with additional extensive between-individual variability. Formulations need to be tailored for dosage variability in the low ranges and also to the clinical characteristics of neonates. A specific focus of interest during neonatal drug development therefore is a need to quantify and limit excipient exposure based on the available knowledge of their safety or toxicity. Until such tailored vials and formulations become available, compounding practices for drug formulations in neonates should be evaluated to guarantee the correct dosing, product stability and safety.
A Generalized Formulation of Demand Response under Market Environments
Nguyen, Minh Y.; Nguyen, Duc M.
2015-06-01
This paper presents a generalized formulation of Demand Response (DR) under deregulated electricity markets. The problem is scheduling and controls the consumption of electrical loads according to the market price to minimize the energy cost over a day. Taking into account the modeling of customers' comfort (i.e., preference), the formulation can be applied to various types of loads including what was traditionally classified as critical loads (e.g., air conditioning, lights). The proposed DR scheme is based on Dynamic Programming (DP) framework and solved by DP backward algorithm in which the stochastic optimization is used to treat the uncertainty, if any occurred in the problem. The proposed formulation is examined with the DR problem of different loads, including Heat Ventilation and Air Conditioning (HVAC), Electric Vehicles (EVs) and a newly DR on the water supply systems of commercial buildings. The result of simulation shows significant saving can be achieved in comparison with their traditional (On/Off) scheme.
Microcanonical formulation of quantum field theories
International Nuclear Information System (INIS)
Iwazaki, A.
1984-03-01
A microcanonical formulation of Euclidean quantum field theories is presented. In the formulation, correlation functions are given by a microcanonical ensemble average of fields. Furthermore, the perturbative equivalence of the formulation and the standard functional formulation is proved and the equipartition low is derived in our formulation. (author)
Quasi-Eulerian formulation for fluid-structure interaction
International Nuclear Information System (INIS)
Kennedy, J.M.; Belytschko, T.B.
1979-01-01
In this paper, recent developments of a quasi-Eulerian finite element formulation for the treatment of the fluid in fluid-structure interaction problems are described. The present formulation is applicable both to plane two-dimensional and axisymmetric three-dimensional problems. In order to reduce the noise associated with the convection terms, an amplification factor is used to implement an up-winding type scheme. The application of the method is illustrated in two problems which are of importance in nuclear reactor safety: 1. A two-dimensional model of a cross section of a subassembly configuration, where the quasi-Eulerian formulation is used to model the fluid adjacent to the structures and in the channel between the subassemblies. 2. Pressure transients in a straight pipe, where the axisymmetric formulation is used to model the fluid in the pipe. These results are compared to experimental results for these problems and compare quite well. The major problem in the application of these methods appears to be the automation of the scheme for moving the fluid nodes. Several alternative schemes are used in the problems described here, and a more general scheme which appears to offer a reasonable (orig.)
Mobile Robots Path Planning Using the Overall Conflict Resolution and Time Baseline Coordination
Directory of Open Access Journals (Sweden)
Yong Ma
2014-01-01
Full Text Available This paper aims at resolving the path planning problem in a time-varying environment based on the idea of overall conflict resolution and the algorithm of time baseline coordination. The basic task of the introduced path planning algorithms is to fulfill the automatic generation of the shortest paths from the defined start poses to their end poses with consideration of generous constraints for multiple mobile robots. Building on this, by using the overall conflict resolution, within the polynomial based paths, we take into account all the constraints including smoothness, motion boundary, kinematics constraints, obstacle avoidance, and safety constraints among robots together. And time baseline coordination algorithm is proposed to process the above formulated problem. The foremost strong point is that much time can be saved with our approach. Numerical simulations verify the effectiveness of our approach.
Preconditioning for Mixed Finite Element Formulations of Elliptic Problems
Wildey, Tim; Xue, Guangri
2013-01-01
In this paper, we discuss a preconditioning technique for mixed finite element discretizations of elliptic equations. The technique is based on a block-diagonal approximation of the mass matrix which maintains the sparsity and positive definiteness of the corresponding Schur complement. This preconditioner arises from the multipoint flux mixed finite element method and is robust with respect to mesh size and is better conditioned for full permeability tensors than a preconditioner based on a diagonal approximation of the mass matrix. © Springer-Verlag Berlin Heidelberg 2013.
Optimal Component Lumping: problem formulation and solution techniques
DEFF Research Database (Denmark)
Lin, Bao; Leibovici, Claude F.; Jørgensen, Sten Bay
2008-01-01
This paper presents a systematic method for optimal lumping of a large number of components in order to minimize the loss of information. In principle, a rigorous composition-based model is preferable to describe a system accurately. However, computational intensity and numerical issues restrict ...
Arbitrary lagrangian-eulerian formulation of quasistatic nonlinear problems
Rodríguez Ferran, Antonio
1996-01-01
En esta tesis se presenta una metodología para la simulación numérica de procesos cuasistaticos en mecánica de sólidos no lineal, basada en una formulación arbitrariamente lagrangiana-euleriana (ale) del problema. Se hace un enfoque generalista, que abarca algunas cuestiones fundamentales en mecánica computacional y en análisis numérico: la resolución de sistemas no lineales de ecuaciones algebraicas y la integración de las ecuaciones constitutivas no lineales. Como entorno de trabajo se util...
An Inverse Problem Formulation Methodology for Stochastic Models
2010-05-02
form the surveillance data Infection control measures were implemented in the form of health care worker hand - hygiene before and after patients contact...manuscript derives from our interest in understanding the spread of infectious diseases in particular, nosocomial infections , in order to prevent major...given by the inverse of the parameter of the exponential distribution. A hand - hygiene policy applied to health care workers on isolated VRE colonized
Tactile friction of topical formulations.
Skedung, L; Buraczewska-Norin, I; Dawood, N; Rutland, M W; Ringstad, L
2016-02-01
The tactile perception is essential for all types of topical formulations (cosmetic, pharmaceutical, medical device) and the possibility to predict the sensorial response by using instrumental methods instead of sensory testing would save time and cost at an early stage product development. Here, we report on an instrumental evaluation method using tactile friction measurements to estimate perceptual attributes of topical formulations. Friction was measured between an index finger and an artificial skin substrate after application of formulations using a force sensor. Both model formulations of liquid crystalline phase structures with significantly different tactile properties, as well as commercial pharmaceutical moisturizing creams being more tactile-similar, were investigated. Friction coefficients were calculated as the ratio of the friction force to the applied load. The structures of the model formulations and phase transitions as a result of water evaporation were identified using optical microscopy. The friction device could distinguish friction coefficients between the phase structures, as well as the commercial creams after spreading and absorption into the substrate. In addition, phase transitions resulting in alterations in the feel of the formulations could be detected. A correlation was established between skin hydration and friction coefficient, where hydrated skin gave rise to higher friction. Also a link between skin smoothening and finger friction was established for the commercial moisturizing creams, although further investigations are needed to analyse this and correlations with other sensorial attributes in more detail. The present investigation shows that tactile friction measurements have potential as an alternative or complement in the evaluation of perception of topical formulations. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Problem Solving with General Semantics.
Hewson, David
1996-01-01
Discusses how to use general semantics formulations to improve problem solving at home or at work--methods come from the areas of artificial intelligence/computer science, engineering, operations research, and psychology. (PA)
The covariant formulation of f ( T ) gravity
International Nuclear Information System (INIS)
Krššák, Martin; Saridakis, Emmanuel N
2016-01-01
We show that the well-known problem of frame dependence and violation of local Lorentz invariance in the usual formulation of f ( T ) gravity is a consequence of neglecting the role of spin connection. We re-formulate f ( T ) gravity starting from, instead of the ‘pure tetrad’ teleparallel gravity, the covariant teleparallel gravity, using both the tetrad and the spin connection as dynamical variables, resulting in a fully covariant, consistent, and frame-independent version of f ( T ) gravity, which does not suffer from the notorious problems of the usual, pure tetrad, f ( T ) theory. We present the method to extract solutions for the most physically important cases, such as the Minkowski, the Friedmann–Robertson–Walker (FRW) and the spherically symmetric ones. We show that in covariant f ( T ) gravity we are allowed to use an arbitrary tetrad in an arbitrary coordinate system along with the corresponding spin connection, resulting always in the same physically relevant field equations. (paper)
Significance of Strain in Formulation in Theory of Solid Mechanics
Patnaik, Surya N.; Coroneos, Rula M.; Hopkins, Dale A.
2003-01-01
The basic theory of solid mechanics was deemed complete circa 1860 when St. Venant provided the strain formulation or the field compatibility condition. The strain formulation was incomplete. The missing portion has been formulated and identified as the boundary compatibility condition (BCC). The BCC, derived through a variational formulation, has been verified through integral theorem and solution of problems. The BCC, unlike the field counterpart, do not trivialize when expressed in displacements. Navier s method and the stiffness formulation have to account for the extra conditions especially at the inter-element boundaries in a finite element model. Completion of the strain formulation has led to the revival of the direct force calculation methods: the Integrated Force Method (IFM) and its dual (IFMD) for finite element analysis, and the completed Beltrami-Michell formulation (CBMF) in elasticity. The benefits from the new methods in elasticity, in finite element analysis, and in design optimization are discussed. Existing solutions and computer codes may have to be adjusted for the compliance of the new conditions. Complacency because the discipline is over a century old and computer codes have been developed for half a century can lead to stagnation of the discipline.
Energy Technology Data Exchange (ETDEWEB)
2017-04-25
Gap Resolution is a software package that was developed to improve Newbler genome assemblies by automating the closure of sequence gaps caused by repetitive regions in the DNA. This is done by performing the follow steps:1) Identify and distribute the data for each gap in sub-projects. 2) Assemble the data associated with each sub-project using a secondary assembler, such as Newbler or PGA. 3) Determine if any gaps are closed after reassembly, and either design fakes (consensus of closed gap) for those that closed or lab experiments for those that require additional data. The software requires as input a genome assembly produce by the Newbler assembler provided by Roche and 454 data containing paired-end reads.
LP formulation of asymmetric zero-sum stochastic games
Li, Lichun
2014-12-15
This paper provides an efficient linear programming (LP) formulation of asymmetric two player zero-sum stochastic games with finite horizon. In these stochastic games, only one player is informed of the state at each stage, and the transition law is only controlled by the informed player. Compared with the LP formulation of extensive stochastic games whose size grows polynomially with respect to the size of the state and the size of the uninformed player\\'s actions, our proposed LP formulation has its size to be linear with respect to the size of the state and the size of the uninformed player, and hence greatly reduces the computational complexity. A travelling inspector problem is used to demonstrate the efficiency of the proposed LP formulation.
LP formulation of asymmetric zero-sum stochastic games
Li, Lichun; Shamma, Jeff S.
2014-01-01
This paper provides an efficient linear programming (LP) formulation of asymmetric two player zero-sum stochastic games with finite horizon. In these stochastic games, only one player is informed of the state at each stage, and the transition law is only controlled by the informed player. Compared with the LP formulation of extensive stochastic games whose size grows polynomially with respect to the size of the state and the size of the uninformed player's actions, our proposed LP formulation has its size to be linear with respect to the size of the state and the size of the uninformed player, and hence greatly reduces the computational complexity. A travelling inspector problem is used to demonstrate the efficiency of the proposed LP formulation.
Decontamination formulation with sorbent additive
Tucker; Mark D. , Comstock; Robert H.
2007-10-16
A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.
International Nuclear Information System (INIS)
Ma, Yong; Wang, Hongwei; Zamirian, M.
2012-01-01
We present a new approach containing two steps to determine conflict-free paths for mobile objects in two and three dimensions with moving obstacles. Firstly, the shortest path of each object is set as goal function which is subject to collision-avoidance criterion, path smoothness, and velocity and acceleration constraints. This problem is formulated as calculus of variation problem (CVP). Using parametrization method, CVP is converted to time-varying nonlinear programming problems (TNLPP) and then resolved. Secondly, move sequence of object is assigned by priority scheme; conflicts are resolved by multilevel conflict resolution strategy. Approach efficiency is confirmed by numerical examples. -- Highlights: ► Approach with parametrization method and conflict resolution strategy is proposed. ► Approach fits for multi-object paths planning in two and three dimensions. ► Single object path planning and multi-object conflict resolution are orderly used. ► Path of each object obtained with parameterization method in the first phase. ► Conflict-free paths gained by multi-object conflict resolution in the second phase.
States in the Hilbert space formulation and in the phase space formulation of quantum mechanics
International Nuclear Information System (INIS)
Tosiek, J.; Brzykcy, P.
2013-01-01
We consider the problem of testing whether a given matrix in the Hilbert space formulation of quantum mechanics or a function considered in the phase space formulation of quantum theory represents a quantum state. We propose several practical criteria for recognising states in these two versions of quantum physics. After minor modifications, they can be applied to check positivity of any operators acting in a Hilbert space or positivity of any functions from an algebra with a ∗-product of Weyl type. -- Highlights: ► Methods of testing whether a given matrix represents a quantum state. ► The Stratonovich–Weyl correspondence on an arbitrary symplectic manifold. ► Criteria for checking whether a function on a symplectic space is a Wigner function
Curcumin nanodisks: formulation and characterization
Ghosh, Mistuni; Singh, Amareshwar T. K.; Xu, Wenwei; Sulchek, Todd; Gordon, Leo I.; Ryan, Robert O.
2010-01-01
Nanodisks (ND) are nanoscale, disk-shaped phospholipid bilayers whose edge is stabilized by apolipoproteins. In the present study, ND were formulated with the bioactive polyphenol, curcumin, at a 6:1 phospholipid:curcumin molar ratio. Atomic force microscopy revealed that curcumin-ND are particles with diameters
Covariant Formulation of Hooke's Law.
Gron, O.
1981-01-01
Introducing a four-vector strain and a four-force stress, Hooke's law is written as a four-vector equation. This formulation is shown to clarify seemingly paradoxical results in connection with uniformly accelerated motion, and rotational motion with angular acceleration. (Author/JN)
Hamiltonian formulation of the supermembrane
International Nuclear Information System (INIS)
Bergshoeff, E.; Sezgin, E.; Tanii, Y.
1987-06-01
The Hamiltonian formulation of the supermembrane theory in eleven dimensions is given. The covariant split of the first and second class constraints is exhibited, and their Dirac brackets are computed. Gauge conditions are imposed in such a way that the reparametrizations of the membrane with divergence free 2-vectors are unfixed. (author). 10 refs
High-resolution method for evolving complex interface networks
Pan, Shucheng; Hu, Xiangyu Y.; Adams, Nikolaus A.
2018-04-01
In this paper we describe a high-resolution transport formulation of the regional level-set approach for an improved prediction of the evolution of complex interface networks. The novelty of this method is twofold: (i) construction of local level sets and reconstruction of a global level set, (ii) local transport of the interface network by employing high-order spatial discretization schemes for improved representation of complex topologies. Various numerical test cases of multi-region flow problems, including triple-point advection, single vortex flow, mean curvature flow, normal driven flow, dry foam dynamics and shock-bubble interaction show that the method is accurate and suitable for a wide range of complex interface-network evolutions. Its overall computational cost is comparable to the Semi-Lagrangian regional level-set method while the prediction accuracy is significantly improved. The approach thus offers a viable alternative to previous interface-network level-set method.
Summary compilation of shell element performance versus formulation.
Energy Technology Data Exchange (ETDEWEB)
Heinstein, Martin Wilhelm; Hales, Jason Dean (Idaho National Laboratory, Idaho Falls, ID); Breivik, Nicole L.; Key, Samuel W. (FMA Development, LLC, Great Falls, MT)
2011-07-01
This document compares the finite element shell formulations in the Sierra Solid Mechanics code. These are finite elements either currently in the Sierra simulation codes Presto and Adagio, or expected to be added to them in time. The list of elements are divided into traditional two-dimensional, plane stress shell finite elements, and three-dimensional solid finite elements that contain either modifications or additional terms designed to represent the bending stiffness expected to be found in shell formulations. These particular finite elements are formulated for finite deformation and inelastic material response, and, as such, are not based on some of the elegant formulations that can be found in an elastic, infinitesimal finite element setting. Each shell element is subjected to a series of 12 verification and validation test problems. The underlying purpose of the tests here is to identify the quality of both the spatially discrete finite element gradient operator and the spatially discrete finite element divergence operator. If the derivation of the finite element is proper, the discrete divergence operator is the transpose of the discrete gradient operator. An overall summary is provided from which one can rank, at least in an average sense, how well the individual formulations can be expected to perform in applications encountered year in and year out. A letter grade has been assigned albeit sometimes subjectively for each shell element and each test problem result. The number of A's, B's, C's, et cetera assigned have been totaled, and a grade point average (GPA) has been computed, based on a 4.0-system. These grades, combined with a comparison between the test problems and the application problem, can be used to guide an analyst to select the element with the best shell formulation.
Path inequalities for the vehicle routing problem with time windows
DEFF Research Database (Denmark)
Kallehauge, Brian; Boland, Natashia; Madsen, Oli B.G.
2007-01-01
In this paper we introduce a new formulation of the vehicle routing problem with time windows (VRPTW) involving only binary variables. The new formulation is based on the formulation of the asymmetric traveling salesman problem with time windows by Ascheuer et al. (Networks 36 (2000) 69-79) and has...
Static And Kinematic Formulation Of Planar Reciprocal Assemblies
DEFF Research Database (Denmark)
Parigi, Dario; Kirkegaard, Poul Henning
2013-01-01
Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed by extending the work on pin-jointed assemblies by Pe...
A Study of the Constraint to Formulation and Implementation of ...
African Journals Online (AJOL)
In recent years, Benin metropolis has been faced with solid waste management problems. Solid wastes generated from household and commercial activities are dump indiscriminately in the metropolis. The Edo state government has made effort in policy formulation and funding in line with the national policy on the ...
Variational formulation based analysis on growth of yield front in ...
African Journals Online (AJOL)
The present study investigates the growth of elastic-plastic front in rotating solid disks of non-uniform thickness having exponential and parabolic geometry variation. The problem is solved through an extension of a variational method in elastoplastic regime. The formulation is based on von-Mises yield criterion and linear ...
Volumetric formulation of lattice Boltzmann models with energy conservation
Sbragaglia, M.; Sugiyama, K.
2010-01-01
We analyze a volumetric formulation of lattice Boltzmann for compressible thermal fluid flows. The velocity set is chosen with the desired accuracy, based on the Gauss-Hermite quadrature procedure, and tested against controlled problems in bounded and unbounded fluids. The method allows the simulation of thermohydrodyamical problems without the need to preserve the exact space-filling nature of the velocity set, but still ensuring the exact conservation laws for density, momentum and energy. ...
Tackling wicked problems: how theories of agency can provide new insights.
Varpio, Lara; Aschenbrener, Carol; Bates, Joanna
2017-04-01
This paper reviews why and how theories of agency can be used as analytical lenses to help health professions education (HPE) scholars address our community's wicked problems. Wicked problems are those that resist clear problem statements, defy traditional analysis approaches, and refuse definitive resolution (e.g. student remediation, assessments of professionalism, etc.). We illustrate how theories of agency can provide new insights into such challenges by examining the application of these theories to one particular wicked problem in HPE: interprofessional education (IPE). After searching the HPE literature and finding that theories of agency had received little attention, we borrowed techniques from narrative literature reviews to search databases indexing a broad scope of disciplines (i.e. ERIC, Web of Science, Scopus, MEDLINE and PubMed) for publications (1994-2014) that: (i) examined agency, or (ii) incorporated an agency-informed analytical perspective. The lead author identified the theories of agency used in these articles, and reviewed the texts on agency cited therein and the original sources of each theory. We identified 10 theories of agency that we considered to be applicable to HPE's wicked problems. To select a subset of theories for presentation in this paper, we discussed each theory in relation to some of HPE's wicked problems. Through debate and reflection, we unanimously agreed on the applicability of a subset of theories for illuminating HPE's wicked problems. This subset is described in this paper. We present four theories of agency: Butler's post-structural formulation; Giddens' sociological formulation; cultural historical activity theory's formulation, and Bandura's social cognitive psychology formulation. We introduce each theory and apply each to the challenges of engaging in IPE. Theories of agency can inform HPE scholarship in novel and generative ways. Each theory offers new insights into the roots of wicked problems and means for
Formulation of marketing information and communication strategies in Taiwan tourism industry
Lee, Tzong-Ru; Kuo, Yu-Hsuan; Hilletofth, Per
2013-01-01
Purpose: The purpose of this research is to formulate marketing information and communication (ICT) strategies for Taiwan tourism industry. Design/methodology/approach: This research uses a literature review to identify problems and solutions of Taiwan’s tourism industry. One of the identified problems is used as an example to formulate marketing ICT strategies. Findings: This research has identified twenty-five main problems and forty-eight solutions of Taiwan’s tourism industry and formulat...
Elementary topology problem textbook
Viro, O Ya; Netsvetaev, N Yu; Kharlamov, V M
2008-01-01
This textbook on elementary topology contains a detailed introduction to general topology and an introduction to algebraic topology via its most classical and elementary segment centered at the notions of fundamental group and covering space. The book is tailored for the reader who is determined to work actively. The proofs of theorems are separated from their formulations and are gathered at the end of each chapter. This makes the book look like a pure problem book and encourages the reader to think through each formulation. A reader who prefers a more traditional style can either find the pr
Projecting India's energy requirements for policy formulation
International Nuclear Information System (INIS)
Parikh, Kirit S.; Karandikar, Vivek; Rana, Ashish; Dani, Prasanna
2009-01-01
Energy policy has to have a long-term perspective. To formulate it one needs to know the contours of energy requirements and options. Different approaches have been followed in literature, each with their own problems. A top down econometric approach provides little guidance on policies, while a bottom up approval requires too much knowledge and too many assumptions. Using top-down econometric approach for aggregate overall benchmarking and a detailed activity analysis model, Integrated Energy System Model, for a few large sectors, provides a unique combination for easing the difficulties of policy formulation. The model is described in this paper. Eleven alternate scenarios are built, designed to map out extreme points of feasible options. Results show that even after employing all domestic energy resource to their full potential, there will be a continued rise of fossil fuel use, continued importance of coal, and continued rise of import dependence. Energy efficiency emerges as a major option with a potential to reduce energy requirement by as much as 17%. Scenario results point towards pushing for development of alternative sources. (author)
Optimization of chlorphenesin emulgel formulation
Mohamed, Magdy I.
2004-01-01
This study was conducted to develop an emulgel formulation of chlorphenesin (CHL) using 2 types of gelling agents: hydroxypropylmethyl cellulose (HPMC) and Carbopol 934. The influence of the type of the gelling agent and the concentration of both the oil phase and emulsifying agent on the drug release from the prepared emulgels was investigated using a 23 factorial design. The prepared emulgels were evaluated for their physical appearance, rheological behavior, drug release, antifungal activi...
A novel super-resolution camera model
Shao, Xiaopeng; Wang, Yi; Xu, Jie; Wang, Lin; Liu, Fei; Luo, Qiuhua; Chen, Xiaodong; Bi, Xiangli
2015-05-01
Aiming to realize super resolution(SR) to single image and video reconstruction, a super resolution camera model is proposed for the problem that the resolution of the images obtained by traditional cameras behave comparatively low. To achieve this function we put a certain driving device such as piezoelectric ceramics in the camera. By controlling the driving device, a set of continuous low resolution(LR) images can be obtained and stored instantaneity, which reflect the randomness of the displacements and the real-time performance of the storage very well. The low resolution image sequences have different redundant information and some particular priori information, thus it is possible to restore super resolution image factually and effectively. The sample method is used to derive the reconstruction principle of super resolution, which analyzes the possible improvement degree of the resolution in theory. The super resolution algorithm based on learning is used to reconstruct single image and the variational Bayesian algorithm is simulated to reconstruct the low resolution images with random displacements, which models the unknown high resolution image, motion parameters and unknown model parameters in one hierarchical Bayesian framework. Utilizing sub-pixel registration method, a super resolution image of the scene can be reconstructed. The results of 16 images reconstruction show that this camera model can increase the image resolution to 2 times, obtaining images with higher resolution in currently available hardware levels.
Giacoia, George P; Taylor-Zapata, Perdita; Mattison, Donald
2007-01-01
The development and compounding of pharmacotherapeutic formulations that are suitable for infants and young children can be a challenging problem. This problem results from the lack of knowledge on the acceptability of different dosage forms and formulations in children in relation to age and developmental status, as well as the lack of reliable documentation of formulations used in pediatric clinical trials. As part of its mandate under the Best Pharmaceuticals for Children Act to improve pediatric therapeutics, the National Institute of Child Health and Human Development has sponsored the Pediatric Formulation Initiative. The goal of this ongoing initiative is to address the issues and concnerns associated with pediatric therapeutics by convening groups of researchers and experts in pediatric formulations from academia, pharmaceutical companies, the National Institutes of Health, and the U.S. Food and Drug Administration.
Regression filter for signal resolution
International Nuclear Information System (INIS)
Matthes, W.
1975-01-01
The problem considered is that of resolving a measured pulse height spectrum of a material mixture, e.g. gamma ray spectrum, Raman spectrum, into a weighed sum of the spectra of the individual constituents. The model on which the analytical formulation is based is described. The problem reduces to that of a multiple linear regression. A stepwise linear regression procedure was constructed. The efficiency of this method was then tested by transforming the procedure in a computer programme which was used to unfold test spectra obtained by mixing some spectra, from a library of arbitrary chosen spectra, and adding a noise component. (U.K.)
Formulation of similarity porous media systems
International Nuclear Information System (INIS)
Anderson, R.M.; Ford, W.T.; Ruttan, A.; Strauss, M.J.
1982-01-01
The mathematical formulation of the Porous Media System (PMS) describing two-phase, immiscible, compressible fluid flow in linear, homogeneous porous media is reviewed and expanded. It is shown that families of common vertex, coaxial parabolas and families of parallel lines are the only families of curves on which solutions of the PMS may be constant. A coordinate transformation is used to change the partial differential equations of the PMS to a system of ordinary differential equations, referred to as a similarity Porous Media System (SPMS), in which the independent variable denotes movement from curve to curve in a selected family of curves. Properties of solutions of the first boundary value problem are developed for the SPMS
Energy policy formulation and energy administration in South Africa
International Nuclear Information System (INIS)
Du Plessis, S.J.P.
1983-01-01
The evolvement of the governmental energy administrative mechanisms is discussed. Energy policy formulation and the role of the Department of Mineral and Energy Affairs in this regard are outlined. The energy administrative process, with reference to various energy carriers and specific spheres of the South African energy economy is discussed. It is indicated that close co-operation between the public and private energy sectors should result in mutual understanding of each others' practical problems and objectives, and should contribute towards the process of judicious energy policy formulation and administration in the interests of the national well-being
Reconcile: A Coreference Resolution Research Platform
Energy Technology Data Exchange (ETDEWEB)
Stoyanov, V; Cardie, C; Gilbert, N; Riloff, E; Buttler, D; Hysom, D
2009-10-29
Despite the availability of standard data sets and metrics, approaches to the problem of noun phrase coreference resolution are hard to compare empirically due to the different evaluation setting stemming, in part, from the lack of comprehensive coreference resolution research platforms. In this tech report we present Reconcile, a coreference resolution research platform that aims to facilitate the implementation of new approaches to coreference resolution as well as the comparison of existing approaches. We discuss Reconcile's architecture and give results of running Reconcile on six data sets using four evaluation metrics, showing that Reconcile's performance is comparable to state-of-the-art systems in coreference resolution.
The Inhibiting Bisection Problem
Energy Technology Data Exchange (ETDEWEB)
Pinar, Ali; Fogel, Yonatan; Lesieutre, Bernard
2006-12-18
Given a graph where each vertex is assigned a generation orconsumption volume, we try to bisect the graph so that each part has asignificant generation/consumption mismatch, and the cutsize of thebisection is small. Our motivation comes from the vulnerability analysisof distribution systems such as the electric power system. We show thatthe constrained version of the problem, where we place either the cutsizeor the mismatch significance as a constraint and optimize the other, isNP-complete, and provide an integer programming formulation. We alsopropose an alternative relaxed formulation, which can trade-off betweenthe two objectives and show that the alternative formulation of theproblem can be solved in polynomial time by a maximum flow solver. Ourexperiments with benchmark electric power systems validate theeffectiveness of our methods.
The optimal graph partitioning problem
DEFF Research Database (Denmark)
Sørensen, Michael Malmros; Holm, Søren
1993-01-01
. This problem can be formulated as a MILP, which turns out to be completely symmetrical with respect to the p classes, and the gap between the relaxed LP solution and the optimal solution is the largest one possible. These two properties make it very difficult to solve even smaller problems. In this paper...
Micosoft Excel Sensitivity Analysis for Linear and Stochastic Program Feed Formulation
Sensitivity analysis is a part of mathematical programming solutions and is used in making nutritional and economic decisions for a given feed formulation problem. The terms, shadow price and reduced cost, are familiar linear program (LP) terms to feed formulators. Because of the nonlinear nature of...
Case Formulation in Psychotherapy: Revitalizing Its Usefulness as a Clinical Tool
Sim, Kang; Gwee, Kok Peng; Bateman, Anthony
2005-01-01
Objective: Case formulation has been recognized to be a useful conceptual and clinical tool in psychotherapy as diagnosis itself does not focus on the underlying causes of a patient's problems. Case formulation can fill the gap between diagnosis and treatment, with the potential to provide insights into the integrative, explanatory, prescriptive,…
Variational principles are a powerful tool also for formulating field theories
Dell'Isola , Francesco; Placidi , Luca
2012-01-01
Variational principles and calculus of variations have always been an important tool for formulating mathematical models for physical phenomena. Variational methods give an efficient and elegant way to formulate and solve mathematical problems that are of interest for scientists and engineers and are the main tool for the axiomatization of physical theories
Perfume formulation: words and chats.
Ellena, Céline
2008-06-01
What does it mean to create fragrances with materials from chemistry and/or from nature? How are they used to display their characteristic differences, their own personality? Is it easier to create with synthetic raw materials or with essential oils? This review explains why a perfume formulation corresponds in fact to a conversation, an interplay between synthetic and natural perfumery materials. A synthetic raw material carries a single information, and usually is very linear. Its smell is uniform, clear, and faithful. Natural raw materials, on the contrary, provide a strong, complex and generous image. While a synthetic material can be seen as a single word, a natural one such as rose oil could be compared to chatting: cold, warm, sticky, heavy, transparent, pepper, green, metallic, smooth, watery, fruity... full of information. Yet, if a very small amount of the natural material is used, nothing happens, the fragrance will not change. However, if a large amount is used, the rose oil will swallow up everything else. The fragrance will smell of nothing else except rose! To formulate a perfume is not to create a culinary recipe, with only dosing the ingredients in well-balanced amounts. To formulate rather means to flexibly knit materials together with a lively stitch, meeting or repelling each other, building a pleasant form, which is neither fixed, nor solid, nor rigid. A fragrance has an overall structure, which ranges from a clear sound, made up of stable, unique, and linear items, to a background chat, comfortable and reassuring. But that does, of course, not mean that there is only one way of creating a fragrance!
Formulation of soy oil products
Directory of Open Access Journals (Sweden)
Woerfel, John B.
1995-12-01
Full Text Available The paper comments different formulations of soy oil products such as salad and cooking oils, margarine, shortenings, commercial shortenings, frying shortenings, and fluid shortenings. Hydrogenation and its influence on final products is also included.
El trabajo presenta diferentes formulaciones a base de aceite de soja tales como aceites para ensalada y cocinado, margarina, grasas sólidas (shortenings, grasas sólidas comerciales, grasas sólidas para frituras y grasas fluidas. Hace también referencia al proceso de hidrogenación y a sus efectos en los productos finales.
Formulation and Characterization of Sustained Release Floating ...
African Journals Online (AJOL)
Purpose: To formulate sustained release gastroretentive microballoons of metformin hydrochloride with the objective of improving its bioavailability. Methods: Microballoons of metformin hydrochloride were formulated by solvent evaporation and diffusion method using varying mixtures of hydroxypropyl methylcellulose ...
Bioequivalence assessment of two formulations of ibuprofen
Al-Talla, Zeyad; Akrawi, Sabah H; Tolley, Luke T; Sioud, Salim H; Zaater, Mohammed F; Emwas, Abdul-Hamid M
2011-01-01
Background: This study assessed the relative bioavailability of two formulations of ibuprofen. The first formulation was Doloraz , produced by Al-Razi Pharmaceutical Company, Amman, Jordan. The second forumulation was Brufen , manufactured by Boots
Modern approach to relativity theory (radar formulation)
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1991-01-01
The main peculiarities of the radar formulation of the relativity theory are presented. This formulation operates with the retarded (light) distances and relativistic or radar length introduced on their basis. 21 refs.; 1 tab
Formulation, Preparation, and Characterization of Polyurethane Foams
Pinto, Moises L.
2010-01-01
Preparation of laboratory-scale polyurethane foams is described with formulations that are easy to implement in experiments for undergraduate students. Particular attention is given to formulation aspects that are based on the main chemical reactions occurring in polyurethane production. This allows students to develop alternative formulations to…
Performance Evaluation of Abrasive Grinding Wheel Formulated ...
African Journals Online (AJOL)
This paper presents a study on the formulation and manufacture of abrasive grinding wheel using locally formulated silicon carbide abrasive grains. Six local raw material substitutes were identified through pilot study and with the initial mix of the identified materials, a systematic search for an optimal formulation of silicon ...
Optimization of chlorphenesin emulgel formulation.
Mohamed, Magdy I
2004-10-11
This study was conducted to develop an emulgel formulation of chlorphenesin (CHL) using 2 types of gelling agents: hydroxypropylmethyl cellulose (HPMC) and Carbopol 934. The influence of the type of the gelling agent and the concentration of both the oil phase and emulsifying agent on the drug release from the prepared emulgels was investigated using a 2(3) factorial design. The prepared emulgels were evaluated for their physical appearance, rheological behavior, drug release, antifungal activity, and stability. Commercially available CHL topical powder was used for comparison. All the prepared emulgels showed acceptable physical properties concerning color, homogeneity, consistency, spreadability, and pH value. They also exhibited higher drug release and antifungal activity than the CHL powder. It was found that the emulsifying agent concentration had the most pronounced effect on the drug release from the emulgels followed by the oil phase concentration and finally the type of the gelling agent. The drug release from all the emulgels was found to follow diffusion-controlled mechanism. Rheological studies revealed that the CHL emulgels exhibited a shear-thinning behavior with thixotropy. Stability studies showed that the physical appearance, rheological properties, drug release, and antifungal activity in all the prepared emulgels remained unchanged upon storage for 3 months. As a general conclusion, it was suggested that the CHL emulgel formulation prepared with HPMC with the oil phase concentration in its low level and emulsifying agent concentration in its high level was the formula of choice since it showed the highest drug release and antifungal activity.
Design of analog networks in the control theory formulation. Part 2: Numerical results
Zemliak, A. M.
2005-01-01
The paper presents numerical results of design of nonlinear electronic networks based on the problem formulation in terms of the control theory. Several examples illustrate the prospects of the approach suggested in the first part of the work.
The Guderley problem revisited
International Nuclear Information System (INIS)
Ramsey, Scott D.; Kamm, James R.; Bolstad, John H.
2009-01-01
The self-similar converging-diverging shock wave problem introduced by Guderley in 1942 has been the source of numerous investigations since its publication. In this paper, we review the simplifications and group invariance properties that lead to a self-similar formulation of this problem from the compressible flow equations for a polytropic gas. The complete solution to the self-similar problem reduces to two coupled nonlinear eigenvalue problems: the eigenvalue of the first is the so-called similarity exponent for the converging flow, and that of the second is a trajectory multiplier for the diverging regime. We provide a clear exposition concerning the reflected shock configuration. Additionally, we introduce a new approximation for the similarity exponent, which we compare with other estimates and numerically computed values. Lastly, we use the Guderley problem as the basis of a quantitative verification analysis of a cell-centered, finite volume, Eulerian compressible flow algorithm.
Formulating natural based cosmetic product - irradiated herbal lip balm
International Nuclear Information System (INIS)
Seri Chempaka Mohd Yusof; Ros Anita Ahmad Ramli; Foziah Ali; Zainab Harun
2007-01-01
Herbal lip balm was formulated in efforts to produce a safe product, attractive with multifunctional usage i.e. prevent chap lips, reduce mouth odour and benefits in improving the health quality. Problems faced in constructing formulations of herbal lip balm were focused to the extraction of anthocyanins, the stability of the pigments in the formulations and changes of colour during irradiation for the sterilization of herbal lip balm. Natural pigment, anthocyanin was used as a colorant agent in herbal lip balm, obtained from various herbs and vegetables i.e. Hibiscus sabdariffa L. (roselle), Brassica oleracea var. capitata f. rubra (red cabbage) and Daucus carota (carrot). Water based extraction method was used in extracting the anthocyanins. The incorporation of honey in the formulations improved the colour of the lip balm. The usage of plant based ingredient i.e. cocoa butter substituting the normal based ingredient i.e. petroleum jelly in lip balm also affecting the colour of herbal lip balm. Irradiation at 2.5, 5.0 and 10 kGy was carried out as preservation and reducing of microbial load of the herbal lip balm and changes in colour were observed in formulations irradiated at 10 kGy. (Author)
Variational formulation and projectional methods for the second order transport equation
International Nuclear Information System (INIS)
Borysiewicz, M.; Stankiewicz, R.
1979-01-01
Herein the variational problem for a second-order boundary value problem for the neutron transport equation is formulated. The projectional methods solving the problem are examined. The approach is compared with that based on the original untransformed form of the neutron transport equation
Mixed finite-element formulations in piezoelectricity and flexoelectricity.
Mao, Sheng; Purohit, Prashant K; Aravas, Nikolaos
2016-06-01
Flexoelectricity, the linear coupling of strain gradient and electric polarization, is inherently a size-dependent phenomenon. The energy storage function for a flexoelectric material depends not only on polarization and strain, but also strain-gradient. Thus, conventional finite-element methods formulated solely on displacement are inadequate to treat flexoelectric solids since gradients raise the order of the governing differential equations. Here, we introduce a computational framework based on a mixed formulation developed previously by one of the present authors and a colleague. This formulation uses displacement and displacement-gradient as separate variables which are constrained in a 'weighted integral sense' to enforce their known relation. We derive a variational formulation for boundary-value problems for piezo- and/or flexoelectric solids. We validate this computational framework against available exact solutions. Our new computational method is applied to more complex problems, including a plate with an elliptical hole, stationary cracks, as well as tension and shear of solids with a repeating unit cell. Our results address several issues of theoretical interest, generate predictions of experimental merit and reveal interesting flexoelectric phenomena with potential for application.
Stiefel, Constanze; Dietzel, Sylvia; Endress, Marc; Morlock, Gertrud E
2016-09-02
Food packaging is designed to provide sufficient protection for the respective filling, legally binding information for the consumers like nutritional facts or filling information, and an attractive appearance to promote the sale. For quality and safety of the package, a regular quality control of the used printing materials is necessary to get consistently good print results, to avoid migration of undesired ink components into the food and to identify potentially faulty ink batches. Analytical approaches, however, have hardly been considered for quality assurance so far due to the lack of robust, suitable methods for the analysis of rarely soluble pigment formulations. Thus, a simple and generic high-performance thin-layer chromatography (HPTLC) method for the separation of different colored pigment formulations was developed on HPTLC plates silica gel 60 by automated multiple development. The gradient system provided a sharp resolution for differently soluble pigment constituents like additives and coating materials. The results of multi-detection allowed a first assignment of the differently detectable bands to particular chemical substance classes (e.g., lipophilic components), enabled the comparison of different commercially available pigment batches and revealed substantial variations in the composition of the batches. Hyphenation of HPTLC with high resolution mass spectrometry and infrared spectroscopy allowed the characterization of single unknown pigment constituents, which may partly be responsible for known quality problems during printing. The newly developed, precise and selective HPTLC method can be used as part of routine quality control for both, incoming pigment batches and monitoring of internal pigment production processes, to secure a consistent pigment composition resulting in consistent ink quality, a faultless print image and safe products. Hyphenation of HPTLC with the A. fischeri bioassay gave first information on the bioactivity or rather
Hydrogen atom in the phase-space formulation of quantum mechanics
International Nuclear Information System (INIS)
Gracia-Bondia, J.M.
1984-01-01
Using a coordinate transformation which regularizes the classical Kepler problem, we show that the hydrogen-atom case may be analytically solved via the phase-space formulation of nonrelativistic quantum mechanics. The problem is essentially reduced to that of a four-dimensional oscillator whose treatment in the phase-space formulation is developed. Furthermore, the method allows us to calculate the Green's function for the H atom in a surprisingly simple way
A bicriterion Steiner tree problem on graph
Directory of Open Access Journals (Sweden)
Vujošević Mirko B.
2003-01-01
Full Text Available This paper presents a formulation of bicriterion Steiner tree problem which is stated as a task of finding a Steiner tree with maximal capacity and minimal length. It is considered as a lexicographic multicriteria problem. This means that the bottleneck Steiner tree problem is solved first. After that, the next optimization problem is stated as a classical minimums Steiner tree problem under the constraint on capacity of the tree. The paper also presents some computational experiments with the multicriteria problem.
Energy Technology Data Exchange (ETDEWEB)
Small, S.; Cottrell, G.; Tanenhaus, M.
1987-01-01
This book collects much of the best research currently available on the problem of lexical ambiguity resolution in the processing of human language. When taken out of context, sentences are usually ambiguous. When actually uttered in a dialogue or written in text, these same sentences often have unique interpretations. The inherent ambiguity of isolated sentences, becomes obvious in the attempt to write a computer program to understand them. Different views have emerged on the nature of context and the mechanisms by which it directs unambiguous understanding of words and sentences. These perspectives are represented and discussed. Eighteen original papers from a valuable source book for cognitive scientists in AI, psycholinguistics, neuropsychology, or theoretical linguistics.
A Resolution Prover for Coalition Logic
Nalon, Cláudia; Zhang, Lan; Dixon, Clare; Hustadt, Ullrich
2014-01-01
We present a prototype tool for automated reasoning for Coalition Logic, a non-normal modal logic that can be used for reasoning about cooperative agency. The theorem prover CLProver is based on recent work on a resolution-based calculus for Coalition Logic that operates on coalition problems, a normal form for Coalition Logic. We provide an overview of coalition problems and of the resolution-based calculus for Coalition Logic. We then give details of the implementation of CLProver and prese...
Formulation development for PREPP concreted waste forms
International Nuclear Information System (INIS)
Neilson, R.M. Jr.; Welch, J.M.
1984-05-01
Analysis of variance and logistic regression techniques have been used to develop models describing the effects of formulation variables and their interactions on compressive strength, solidification, free-standing water, and workability of hydraulic cement grouts incorporating simulated Process Experimental Pilot Plant (PREPP) wastes. These models provide the basis for specifications of grout formulations to solidify these wastes. The experimental test matrix, formulation preparation, and test methods employed are described. The development of analytical models for formulation behavior and the conclusions drawn regarding appropriate formulation variable ranges are discussed. 13 references, 9 figures, 15 tables
Energy Technology Data Exchange (ETDEWEB)
Lillie, R.A.; Robinson, J.C.
1976-05-01
The discrete ordinates method is the most powerful and generally used deterministic method to obtain approximate solutions of the Boltzmann transport equation. A finite element formulation, utilizing a canonical form of the transport equation, is here developed to obtain both integral and pointwise solutions to neutron transport problems. The formulation is based on the use of linear triangles. A general treatment of anisotropic scattering is included by employing discrete ordinates-like approximations. In addition, multigroup source outer iteration techniques are employed to perform group-dependent calculations. The ability of the formulation to reduce substantially ray effects and its ability to perform streaming calculations are demonstrated by analyzing a series of test problems. The anisotropic scattering and multigroup treatments used in the development of the formulation are verified by a number of one-dimensional comparisons. These comparisons also demonstrate the relative accuracy of the formulation in predicting integral parameters. The applicability of the formulation to nonorthogonal planar geometries is demonstrated by analyzing a hexagonal-type lattice. A small, high-leakage reactor model is analyzed to investigate the effects of varying both the spatial mesh and order of angular quadrature. This analysis reveals that these effects are more pronounced in the present formulation than in other conventional formulations. However, the insignificance of these effects is demonstrated by analyzing a realistic reactor configuration. In addition, this final analysis illustrates the importance of incorporating anisotropic scattering into the finite element formulation. 8 tables, 29 figures.
International Nuclear Information System (INIS)
Lillie, R.A.; Robinson, J.C.
1976-05-01
The discrete ordinates method is the most powerful and generally used deterministic method to obtain approximate solutions of the Boltzmann transport equation. A finite element formulation, utilizing a canonical form of the transport equation, is here developed to obtain both integral and pointwise solutions to neutron transport problems. The formulation is based on the use of linear triangles. A general treatment of anisotropic scattering is included by employing discrete ordinates-like approximations. In addition, multigroup source outer iteration techniques are employed to perform group-dependent calculations. The ability of the formulation to reduce substantially ray effects and its ability to perform streaming calculations are demonstrated by analyzing a series of test problems. The anisotropic scattering and multigroup treatments used in the development of the formulation are verified by a number of one-dimensional comparisons. These comparisons also demonstrate the relative accuracy of the formulation in predicting integral parameters. The applicability of the formulation to nonorthogonal planar geometries is demonstrated by analyzing a hexagonal-type lattice. A small, high-leakage reactor model is analyzed to investigate the effects of varying both the spatial mesh and order of angular quadrature. This analysis reveals that these effects are more pronounced in the present formulation than in other conventional formulations. However, the insignificance of these effects is demonstrated by analyzing a realistic reactor configuration. In addition, this final analysis illustrates the importance of incorporating anisotropic scattering into the finite element formulation. 8 tables, 29 figures
Iterative Reconstruction Methods for Inverse Problems in Tomography with Hybrid Data
DEFF Research Database (Denmark)
Sherina, Ekaterina
. The goal of these modalities is to quantify physical parameters of materials or tissues inside an object from given interior data, which is measured everywhere inside the object. The advantage of these modalities is that large variations in physical parameters can be resolved and therefore, they have...... data is precisely the reason why reconstructions with a high contrast and a high resolution can be expected. The main contributions of this thesis consist in formulating the underlying mathematical problems with interior data as nonlinear operator equations, theoretically analysing them within...... iteration and the Levenberg-Marquardt method are employed for solving the problems. The first problem considered in this thesis is a problem of conductivity estimation from interior measurements of the power density, known as Acousto-Electrical Tomography. A special case of limited angle tomography...
Development of grout formulations for 106-AN waste: Mixture-experiment results and analysis
International Nuclear Information System (INIS)
Spence, R.D.; McDaniel, E.W.; Anderson, C.M.; Lokken, R.O.; Piepel, G.F.
1993-09-01
Twenty potential ingredients were identified for use in developing a 106-AN grout formulation, and 18 were subsequently obtained and tested. Four ingredients-Type II-LA (moderate heat of hydration) Portland cement, Class F fly ash, attapulgite 150 drilling clay, and ground air-cooled blast-furnace slag (GABFS) were selected for developing the 106-AN grout formulations. A mixture experiment was designed and conducted around the following formulation: 2.5 lb of cement per gallon, 1.2 lb of fly ash per gallon, 0.8 lb of attapulgite per gallon, and 3.5 lb of GABFS per gallon. Reduced empirical models were generated from the results of the mixture experiment. These models were used to recommend several grout formulations for 106-AN. Westinghouse Hanford Company selected one of these formulations to be verified for use with 106-AN and a backup formulation in case problems arise with the first choice
Energy policy formulation for Pakistan
International Nuclear Information System (INIS)
Riaz, T.
1981-01-01
Pakistan is a low income, low energy consumption country. In view of the close interdependence between economic growth and energy consumption, she will need increasing energy supplies in order to maintain her economic growth. This paper develops an energy sector optimization model for the Pakistan economy, which consists of production models for five energy industries, ie oil, gas, coal, electricity (including electricity generated in nuclear power plants) and non-commercial fuels. The model is first used to forecast energy balances for the period 1975 - 2006. The model is then employed to formulate a long-term comprehensive energy policy for Pakistan. Finally the suggested policy is compared with the current official energy programme. (author)
On Scalar Energy: Mathematical Formulation
International Nuclear Information System (INIS)
Hathout, A.M.
2011-01-01
A new kind of electromagnetic waves (EMW), which exists only in vacuum of the empty space, will be discussed and mathematically formulated in this paper. The mathematical existence of this energy was first proposed in a series of groundbreaking equations by Scottish Mathematician, James Clerk Maxwell, in the mid of 1800 and 39;s. This energy is called scalar energy. It is characterized by both particle and wave like. The waves of this energy are called longitudinal EMW to distinguish them from transverse EM, the kind we are familiar with in our daily life. Teslas name of this energy is scalar energy or zero point energy. It is aimed at this paper to explain more details and to verify the scalar EM concept in vacuum.
Adjoint-consistent formulations of slip models for coupled electroosmotic flow systems
Garg, Vikram V
2014-09-27
Background Models based on the Helmholtz `slip\\' approximation are often used for the simulation of electroosmotic flows. The objectives of this paper are to construct adjoint-consistent formulations of such models, and to develop adjoint-based numerical tools for adaptive mesh refinement and parameter sensitivity analysis. Methods We show that the direct formulation of the `slip\\' model is adjoint inconsistent, and leads to an ill-posed adjoint problem. We propose a modified formulation of the coupled `slip\\' model, which is shown to be well-posed, and therefore automatically adjoint-consistent. Results Numerical examples are presented to illustrate the computation and use of the adjoint solution in two-dimensional microfluidics problems. Conclusions An adjoint-consistent formulation for Helmholtz `slip\\' models of electroosmotic flows has been proposed. This formulation provides adjoint solutions that can be reliably used for mesh refinement and sensitivity analysis.
Fem Formulation for Heat and Mass Transfer in Porous Medium
Azeem; Soudagar, Manzoor Elahi M.; Salman Ahmed, N. J.; Anjum Badruddin, Irfan
2017-08-01
Heat and mass transfer in porous medium can be modelled using three partial differential equations namely, momentum equation, energy equation and mass diffusion. These three equations are coupled to each other by some common terms that turn the whole phenomenon into a complex problem with inter-dependable variables. The current article describes the finite element formulation of heat and mass transfer in porous medium with respect to Cartesian coordinates. The problem under study is formulated into algebraic form of equations by using Galerkin's method with the help of two-node linear triangular element having three nodes. The domain is meshed with smaller sized elements near the wall region and bigger size away from walls.
A generalized transport-velocity formulation for smoothed particle hydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Zhang, Chi; Hu, Xiangyu Y., E-mail: xiangyu.hu@tum.de; Adams, Nikolaus A.
2017-05-15
The standard smoothed particle hydrodynamics (SPH) method suffers from tensile instability. In fluid-dynamics simulations this instability leads to particle clumping and void regions when negative pressure occurs. In solid-dynamics simulations, it results in unphysical structure fragmentation. In this work the transport-velocity formulation of Adami et al. (2013) is generalized for providing a solution of this long-standing problem. Other than imposing a global background pressure, a variable background pressure is used to modify the particle transport velocity and eliminate the tensile instability completely. Furthermore, such a modification is localized by defining a shortened smoothing length. The generalized formulation is suitable for fluid and solid materials with and without free surfaces. The results of extensive numerical tests on both fluid and solid dynamics problems indicate that the new method provides a unified approach for multi-physics SPH simulations.
Formulation of poorly water-soluble Gemfibrozil applying power ultrasound.
Ambrus, R; Naghipour Amirzadi, N; Aigner, Z; Szabó-Révész, P
2012-03-01
The dissolution properties of a drug and its release from the dosage form have a basic impact on its bioavailability. Solubility problems are a major challenge for the pharmaceutical industry as concerns the development of new pharmaceutical products. Formulation problems may possibly be overcome by modification of particle size and morphology. The application of power ultrasound is a novel possibility in drug formulation. This article reports on solvent diffusion and melt emulsification, as new methods supplemented with drying in the field of sonocrystallization of poorly water-soluble Gemfibrozil. During thermoanalytical characterization, a modified structure was detected. The specific surface area of the drug was increased following particle size reduction and the poor wettability properties could also be improved. The dissolution rate was therefore significantly increased. Copyright © 2011 Elsevier B.V. All rights reserved.
She, James
2009-11-01
Emerging technologies in Broadband Wireless Access (BWA) networks and video coding have enabled high-quality wireless video broadcast/multicast services in metropolitan areas. Joint source-channel coded wireless transmission, especially using hierarchical/superposition coded modulation at the channel, is recognized as an effective and scalable approach to increase the system scalability while tackling the multi-user channel diversity problem. The power allocation and modulation selection problem, however, is subject to a high computational complexity due to the nonlinear formulation and huge solution space. This paper introduces a dynamic programming framework with conditioned parsing, which significantly reduces the search space. The optimized result is further verified with experiments using real video content. The proposed approach effectively serves as a generalized and practical optimization framework that can gauge and optimize a scalable wireless video broadcast/multicast based on multi-resolution modulation in any BWA network.
She, James; Ho, Pin-Han; Shihada, Basem
2009-01-01
Emerging technologies in Broadband Wireless Access (BWA) networks and video coding have enabled high-quality wireless video broadcast/multicast services in metropolitan areas. Joint source-channel coded wireless transmission, especially using hierarchical/superposition coded modulation at the channel, is recognized as an effective and scalable approach to increase the system scalability while tackling the multi-user channel diversity problem. The power allocation and modulation selection problem, however, is subject to a high computational complexity due to the nonlinear formulation and huge solution space. This paper introduces a dynamic programming framework with conditioned parsing, which significantly reduces the search space. The optimized result is further verified with experiments using real video content. The proposed approach effectively serves as a generalized and practical optimization framework that can gauge and optimize a scalable wireless video broadcast/multicast based on multi-resolution modulation in any BWA network.
... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady. You may ... related injuries, such as a hip fracture. Some balance problems are due to problems in the inner ...
Strategy Formulation and Implementation for PT.Multigarmen Jaya
Yoanita, Martha; Wandebori, Harimukti
2013-01-01
- The objective of this final project is to formulate and proposed the strategy for PT.Multigarmen Jaya (PT.MGJ) to faced the tight competition in garment industries. The analysis begins from environmental analysis that consist of external and internal analysis. For external analysis used PEST, Porter five forces, and competitor analysis, and for internal analysis used value chain analysis and resources analysis. From that analysis, there are several problems discovered, such as competitor ...
Neural networks to formulate special fats
Directory of Open Access Journals (Sweden)
Garcia, R. K.
2012-09-01
Full Text Available Neural networks are a branch of artificial intelligence based on the structure and development of biological systems, having as its main characteristic the ability to learn and generalize knowledge. They are used for solving complex problems for which traditional computing systems have a low efficiency. To date, applications have been proposed for different sectors and activities. In the area of fats and oils, the use of neural networks has focused mainly on two issues: the detection of adulteration and the development of fatty products. The formulation of fats for specific uses is the classic case of a complex problem where an expert or group of experts defines the proportions of each base, which, when mixed, provide the specifications for the desired product. Some conventional computer systems are currently available to assist the experts; however, these systems have some shortcomings. This article describes in detail a system for formulating fatty products, shortenings or special fats, from three or more components by using neural networks (MIX. All stages of development, including design, construction, training, evaluation, and operation of the network will be outlined.
Las redes neuronales son una rama de la inteligencia artificial basadas en la estructura y funcionamiento de sistemas biológicos, teniendo como principal característica la capacidad de aprender y generalizar conocimiento. Estas son utilizadas en la resolución de problemas complejos, en los cuales los sistemas computacionales tradicionales presentan una eficiencia baja. Hasta la fecha, han sido propuestas aplicaciones para los más diversos sectores y actividades. En el área de grasas y aceites, la utilización de redes neuronales se ha concentrado principalmente en dos asuntos: la detección de adulteraciones y la formulación de productos grasos. La formulación de grasas para uso específico es el caso clásico de problema complejo donde un experto o grupo de
Hub location problems in transportation networks
DEFF Research Database (Denmark)
Gelareh, Shahin; Nickel, Stefan
2011-01-01
In this paper we propose a 4-index formulation for the uncapacitated multiple allocation hub location problem tailored for urban transport and liner shipping network design. This formulation is very tight and most of the tractable instances for MIP solvers are optimally solvable at the root node....... also introduce fixed cost values for Australian Post (AP) dataset....
KINOFORM LENSES - TOWARD NANOMETER RESOLUTION.
Energy Technology Data Exchange (ETDEWEB)
STEIN, A.; EVANS-LUTTERODT, K.; TAYLOR, A.
2004-10-23
While hard x-rays have wavelengths in the nanometer and sub-nanometer range, the ability to focus them is limited by the quality of sources and optics, and not by the wavelength. A few options, including reflective (mirrors), diffractive (zone plates) and refractive (CRL's) are available, each with their own limitations. Here we present our work with kinoform lenses which are refractive lenses with all material causing redundant 2{pi} phase shifts removed to reduce the absorption problems inherently limiting the resolution of refractive lenses. By stacking kinoform lenses together, the effective numerical aperture, and thus the focusing resolution, can be increased. The present status of kinoform lens fabrication and testing at Brookhaven is presented as well as future plans toward achieving nanometer resolution.
Energy Technology Data Exchange (ETDEWEB)
McDougall, N.A. (Oxford Univ. (UK). Dept. of Theoretical Physics)
1984-08-23
The resolution of the U(1) problem requires the quark condensates to have a specific THETA dependence. We show that the required THETA dependence arises naturally upon application of the index theorem during the calculation of the dynamically generated quark mass.
[Population problem, comprehension problem].
Tallon, F
1993-08-01
Overpopulation of developing countries in general, and Rwanda in particular, is not just their problem but a problem for developed countries as well. Rapid population growth is a key factor in the increase of poverty in sub-Saharan Africa. Population growth outstrips food production. Africa receives more and more foreign food, economic, and family planning aid each year. The Government of Rwanda encourages reduced population growth. Some people criticize it, but this criticism results in mortality and suffering. One must combat this ignorance, but attitudes change slowly. Some of these same people find the government's acceptance of family planning an invasion of their privacy. Others complain that rich countries do not have campaigns to reduce births, so why should Rwanda do so? The rate of schooling does not increase in Africa, even though the number of children in school increases, because of rapid population growth. Education is key to improvements in Africa's socioeconomic growth. Thus, Africa, is underpopulated in terms of potentiality but overpopulated in terms of reality, current conditions, and possibilities of overexploitation. Africa needs to invest in human resources. Families need to save, and to so, they must refrain from having many children. Africa should resist the temptation to waste, as rich countries do, and denounce it. Africa needs to become more independent of these countries, but structural adjustment plans, growing debt, and rapid population growth limit national independence. Food aid is a means for developed countries to dominate developing countries. Modernization through foreign aid has had some positive effects on developing countries (e.g., improved hygiene, mortality reduction), but these also sparked rapid population growth. Rwandan society is no longer traditional, but it is also not yet modern. A change in mentality to fewer births, better quality of life for living infants, better education, and less burden for women must occur
Resolution effects in reconstructing ancestral genomes.
Zheng, Chunfang; Jeong, Yuji; Turcotte, Madisyn Gabrielle; Sankoff, David
2018-05-09
The reconstruction of ancestral genomes must deal with the problem of resolution, necessarily involving a trade-off between trying to identify genomic details and being overwhelmed by noise at higher resolutions. We use the median reconstruction at the synteny block level, of the ancestral genome of the order Gentianales, based on coffee, Rhazya stricta and grape, to exemplify the effects of resolution (granularity) on comparative genomic analyses. We show how decreased resolution blurs the differences between evolving genomes, with respect to rate, mutational process and other characteristics.
Automated Conflict Resolution For Air Traffic Control
Erzberger, Heinz
2005-01-01
The ability to detect and resolve conflicts automatically is considered to be an essential requirement for the next generation air traffic control system. While systems for automated conflict detection have been used operationally by controllers for more than 20 years, automated resolution systems have so far not reached the level of maturity required for operational deployment. Analytical models and algorithms for automated resolution have been traffic conditions to demonstrate that they can handle the complete spectrum of conflict situations encountered in actual operations. The resolution algorithm described in this paper was formulated to meet the performance requirements of the Automated Airspace Concept (AAC). The AAC, which was described in a recent paper [1], is a candidate for the next generation air traffic control system. The AAC's performance objectives are to increase safety and airspace capacity and to accommodate user preferences in flight operations to the greatest extent possible. In the AAC, resolution trajectories are generated by an automation system on the ground and sent to the aircraft autonomously via data link .The algorithm generating the trajectories must take into account the performance characteristics of the aircraft, the route structure of the airway system, and be capable of resolving all types of conflicts for properly equipped aircraft without requiring supervision and approval by a controller. Furthermore, the resolution trajectories should be compatible with the clearances, vectors and flight plan amendments that controllers customarily issue to pilots in resolving conflicts. The algorithm described herein, although formulated specifically to meet the needs of the AAC, provides a generic engine for resolving conflicts. Thus, it can be incorporated into any operational concept that requires a method for automated resolution, including concepts for autonomous air to air resolution.
Nonequilibrium formulation of abelian gauge theories
Energy Technology Data Exchange (ETDEWEB)
Zoeller, Thorsten
2013-09-01
This work is about a formulation of abelian gauge theories out-of-equilibrium. In contrast to thermal equilibrium, systems out-of-equilibrium are not constant in time, and the interesting questions in such systems refer to time evolution problems. After a short introduction to quantum electrodynamics (QED), the two-particle irreducible (2PI) effective action is introduced as an essential technique for the study of quantum field theories out-of-equilibrium. The equations of motion (EOMs) for the propagators of the theory are then derived from it. It follows a discussion of the physical degrees of freedom (DOFs) of the theory, in particular with respect to the photons, since in covariant formulations of gauge theories unphysical DOFs are necessarily contained. After that the EOMs for the photon propagator are examined more closely. It turns out that they are structurally complicated, and a reformulation of the equations is presented which for the untruncated theory leads to an essential structural simplification of the EOMs. After providing the initial conditions which are necessary in order to solve the EOMs, the free photon EOMs are solved with the help of the reformulated equations. It turns out that the solutions diverge in time, i.e. they are secular. This is a manifestation of the fact that gauge theories contain unphysical DOFs. It is reasoned that these secularities exist only in the free case and are therefore ''artificial''. It is however emphasized that they may not be a problem in principle, but certainly are in practice, in particular for the numerical solution of the EOMs. Further, the origin of the secularities, for which there exists an illustrative explanation, is discussed in more detail. Another characteristic feature of 2PI formulations of gauge theories is the fact that quantities calculated from approximations of the 2PI effective action, which are gauge invariant in the exact theory as well as in an approximated theory at
Slag-based saltstone formulations
International Nuclear Information System (INIS)
Langton, C.A.
1987-01-01
Approximately 400 x 10 6 liters of low-level alkaline salt solution will be treated at the Savannah River Plant (SRP) Defense Waste Processing Facility (DWPF) prior to disposal in concrete vaults at SRP. Treatment involves removal of CS + and Sr +2 followed by solidification and stabilization of potential contaminants in saltstone, a hydrated ceramic waste form. Chromium, technetium, and nitrate releases from saltstone can be significantly reduced by substituting hydraulic blast furnace slag for portland cement in the formulation designs. Slag-based mixes are also compatible with Class F fly ash used in saltstone as a functional extender to control heat of hydration and reduce permeability. A monolithic waste form is produced by the hydration of the slag and fly ash. Soluble ion release (NO 3 - ) is controlled by the saltstone microstructure. Chromium and technetium are less leachable from slag mixes compared to cement-based waste forms because these species are chemically reduced to a lower valence state by ferrous iron in the slag and precipitated as relatively insoluble phases, such as CR(OH) 3 and TcO 2 . 5 refs., 4 figs., 4 tabs
Slag-based saltstone formulations
International Nuclear Information System (INIS)
Langton, C.A.
1987-08-01
Approximately 400 x 10 6 L of low-level alkaline salt solution will be treated at the Savannah River Plant (SRP) Defense Waste Processing Facility (DWPF) prior to disposal in concrete vaults at SRP. Treatment involves removal of Cs + and Sr +2 , followed by solidification and stabilization of potential contaminants in saltstone, a hydrated ceramic wasteform. Chromium, technetium, and nitrate releases from saltstone can be significantly reduced by substituting hydraulic blast furnace slag for portland cement in the formulation designs. Slag-based mixes are also compatible with the Class F flyash used in saltstone as a functional extender to control heat of hydration and reduce permeability. (Class F flyash is also locally available at SRP.) A monolithic wasteform is produced by the hydration of the slag and flyash. Soluble ion release (NO 3- ) is controlled by the saltstone microstructure. Chromium and technetium are less leachable from slag mixes because these species are chemically reduced to a lower valence state by ferrous iron in the slag and are precipitated as relatively insoluble phases, such as Cr(OH) 3 and TcO 2 . 3 refs., 3 figs., 2 tabs
Hamiltonian formulation of reduced magnetohydrodynamics
International Nuclear Information System (INIS)
Morrison, P.J.; Hazeltine, R.D.
1983-07-01
Reduced magnetohydrodynamics (RMHD) has become a principal tool for understanding nonlinear processes, including disruptions, in tokamak plasmas. Although analytical studies of RMHD turbulence have been useful, the model's impressive ability to simulate tokamak fluid behavior has been revealed primarily by numerical solution. The present work describes a new analytical approach, not restricted to turbulent regimes, based on Hamiltonian field theory. It is shown that the nonlinear (ideal) RMHD system, in both its high-beta and low-beta versions, can be expressed in Hanmiltonian form. Thus a Poisson bracket, [ , ], is constructed such that each RMHD field quantitity, xi/sub i/, evolves according to xi/sub i/ = [xi/sub i/,H], where H is the total field energy. The new formulation makes RMHD accessible to the methodology of Hamiltonian mechanics; it has lead, in particular, to the recognition of new RMHD invariants and even exact, nonlinear RMHD solutions. A canonical version of the Poisson bracket, which requires the introduction of additional fields, leads to a nonlinear variational principle for time-dependent RMHD
Formulation of disperse systems science and technology
Tadros, Tharwat F
2014-01-01
This book presents comprehensively the science and technology behind the formulation of disperse systems like emulsions, suspensions, foams and others. Starting with a general introduction, the book covers a broad range of topics like the role of different classes of surfactants, stability of disperse systems, formulation of different dispersions, evaluation of formulations and many more. Many examples are included, too. Written by the experienced author and editor Tharwart Tadros, this book is indispensable for every scientist working in the field.
Formulated arthropod cadavers for pest suppression
2001-01-01
Pesticidal and/or antimicrobial biological agent-infected arthropod cadavers are formulated by applying a coating agent once on the surface of the cadaver which either (a) prevents the cadavers from sticking together and/or rupturing or (b) acts as an adhesive for a powder or granule applied to the cadaver to prevent sticking and rupturing. The formulated cadavers maintain or improve infectivity, reproducibility, and survivability. The formulated cadavers can be partially desiccated to improv...
Resolution of the Staff Council
Staff Association
2015-01-01
You were many to attend the public information meetings organised in October and we thank you for your interest. In this decision phase of the current Five-Yearly Review of our employment conditions they provided an opportunity to review the Management proposals in detail. They were a moment of exchange also on the various topics under review, and your comments were many and very valuable. Meeting on Thursday 29th October, the Staff Council discussed once more these proposals. It considered that the "package" of proposed measures is not balanced enough in its current form. It decided to formulate additional requests to the Management, relating mainly to the effects of the introduction of the proposed new career system. The resolution adopted this morning also implies that the consultation of staff, originally foreseen next week, is postponed. The staff Council will reconvene in a special session on Thursday, 5th November to reassess its position depending on the progress made regarding its d...
A Methodology for Validation of High Resolution Combat Models
1988-06-01
TELEOLOGICAL PROBLEM ................................ 7 C. EPISTEMOLOGICAL PROBLEM ............................. 8 D. UNCERTAINTY PRINCIPLE...theoretical issues. "The Teleological Problem"--How a model by its nature formulates an explicit cause-and-effect relationship that excludes other...34experts" in establishing the standard for reality. Generalization from personal experience is often hampered by the parochial aspects of the
Bivium as a Mixed Integer Programming Problem
DEFF Research Database (Denmark)
Borghoff, Julia; Knudsen, Lars Ramkilde; Stolpe, Mathias
2009-01-01
over $GF(2)$ into a combinatorial optimization problem. We convert the Boolean equation system into an equation system over $\\mathbb{R}$ and formulate the problem of finding a $0$-$1$-valued solution for the system as a mixed-integer programming problem. This enables us to make use of several...
New formulations for tsunami runup estimation
Kanoglu, U.; Aydin, B.; Ceylan, N.
2017-12-01
We evaluate shoreline motion and maximum runup in two folds: One, we use linear shallow water-wave equations over a sloping beach and solve as initial-boundary value problem similar to the nonlinear solution of Aydın and Kanoglu (2017, Pure Appl. Geophys., https://doi.org/10.1007/s00024-017-1508-z). Methodology we present here is simple; it involves eigenfunction expansion and, hence, avoids integral transform techniques. We then use several different types of initial wave profiles with and without initial velocity, estimate shoreline properties and confirm classical runup invariance between linear and nonlinear theories. Two, we use the nonlinear shallow water-wave solution of Kanoglu (2004, J. Fluid Mech. 513, 363-372) to estimate maximum runup. Kanoglu (2004) presented a simple integral solution for the nonlinear shallow water-wave equations using the classical Carrier and Greenspan transformation, and further extended shoreline position and velocity to a simpler integral formulation. In addition, Tinti and Tonini (2005, J. Fluid Mech. 535, 33-64) defined initial condition in a very convenient form for near-shore events. We use Tinti and Tonini (2005) type initial condition in Kanoglu's (2004) shoreline integral solution, which leads further simplified estimates for shoreline position and velocity, i.e. algebraic relation. We then use this algebraic runup estimate to investigate effect of earthquake source parameters on maximum runup and present results similar to Sepulveda and Liu (2016, Coast. Eng. 112, 57-68).
Superspace formulation of new nonlinear sigma models
International Nuclear Information System (INIS)
Gates, S.J. Jr.
1983-07-01
The superspace formulation of two classes of supersymmetric nonlinear σ-models are presented. Two alternative N=1 superspace formulations are given for the d=2 supersymmetric nonlinear σ-models with Killing vector potentials: (a) formulation uses an active central charge and, (b) formulation uses a spurion superfield without inducing a classical breakdown of supersymmetry. The N=2 vector multiplet is used to construct a new class of d=4 nonlinear σ-models which when reduced to d=2 possess N=4 supersymmetry. Implications of these two classes of nonlinear σ-models for N>=4 superfield supergravity are discussed. (author)
Energy Technology Data Exchange (ETDEWEB)
Duran, Ana Cecilia
1990-03-01
This thesis aims to find a better way to solve large scale nonlinear sparse system problems giving special emphasis to load flow in electric power networks. The suggested algorithms are presented 63 refs., 28 figs., 16 tabs.
Alternative dispute resolution mechanisms, plea bargain and ...
African Journals Online (AJOL)
Conflicts, disputes, disagreements, problems and issues are inevitable in human affairs. Most of these disputes and problems in some circumstances give rise to offences for which a criminal prosecution becomes necessary. One can say that Alternative Dispute Resolution (ADR) is used all round the world to resolve ...
Two Fundamental Problems Connected with AI
Dobrev, Dimiter
2008-01-01
This paper is about two fundamental problems in the field of computer science. Solving these two problems is important because it has to do with the creation of Artificial Intelligence. In fact, these two problems are not very famous because they have not many applications outside the field of Artificial Intelligence. In this paper we will give a solution neither of the first nor of the second problem. Our goal will be to formulate these two problems and to give some ideas for...
Time-evolution problem in Regge calculus
International Nuclear Information System (INIS)
Sorkin, R.
1975-01-01
The simplectic approximation to Einstein's equations (''Regge calculus'') is derived by considering the net to be actually a (singular) Riemannian manifold. Specific nets for open and closed spaces are introduced in terms of which one can formulate the general time-evolution problem, which thereby reduces to the repeated solution of finite sets of coupled nonlinear (algebraic) equations. The initial-value problem is also formulated in simplectic terms
Thermal processing of EVA encapsulants and effects of formulation additives
Energy Technology Data Exchange (ETDEWEB)
Pern, F.J.; Glick, S.H. [National Renewable Energy Lab., Golden, CO (United States)
1996-05-01
The authors investigated the in-situ processing temperatures and effects of various formulation additives on the formation of ultraviolet (UV) excitable chromophores, in the thermal lamination and curing of ethylene-vinyl acetate (EVA) encapsulants. A programmable, microprocessor-controlled, double-bag vacuum laminator was used to study two commercial as formulated EVA films, A9918P and 15295P, and solution-cast films of Elvaxrm (EVX) impregnated with various curing agents and antioxidants. The results show that the actual measured temperatures of EVA lagged significantly behind the programmed profiles for the heating elements and were affected by the total thermal mass loaded inside the laminator chamber. The antioxidant Naugard P{trademark}, used in the two commercial EVA formulations, greatly enhances the formation of UV-excitable, short chromophores upon curing, whereas other tested antioxidants show little effect. A new curing agent chosen specifically for the EVA formulation modification produces little or no effect on chromophore formation, no bubbling problems in the glass/EVX/glass laminates, and a gel content of {approximately}80% when cured at programmed 155{degrees}C for 4 min. Also demonstrated is the greater discoloring effect with higher concentrations of curing-generated chromophores.
Usage of humic materials for formulation of stable microbial inoculants
Kydralieva, K. A.; Khudaibergenova, B. M.; Elchin, A. A.; Gorbunova, N. V.; Muratov, V. S.; Jorobekova, Sh. J.
2009-04-01
Some microbes have been domesticated for environment service, for example in a variety of novel applications, including efforts to reduce environmental problems. For instance, antagonistic organisms can be used as biological control agents to reduce the use of chemical pesticides, or efficient degraders can be applied as bioprophylactics to minimise the spread of chemical pollutants. Microorganisms can also be used for the biological clean-up of polluted soil or as plant growth-promoting bacteria that stimulate nutrient uptake. Many microbial applications require large-scale cultivation of the organisms. The biomass production must then be followed by formulation steps to ensure long-term stability and convenient use. However, there remains a need to further develop knowledge on how to optimise fermentation of "non-conventional microorganisms" for environmental applications involving the intact living cells. The goal of presented study is to develop fermentation and formulation techniques for termolabile rhizobacteria isolates - Pseudomonas spp. with major biotechnical potential. Development of efficient and cost-effective media and process parameters giving high cell yields are important priorities. This also involves establishing fermentation parameters yielding cells well adapted to subsequent formulation procedures. Collectively, these strategies will deliver a high proportion of viable cells with good long-term survival. Our main efforts were focused on development of more efficient drying techniques for microorganisms, particularly spray drying and fluidised bed-drying. The advantages of dry formulations are that storage and delivery costs are much lower than for liquid formulations and that long-term survival can be very high if initial packaging is carefully optimised. In order to improve and optimise formulations various kinds of humics-based excipients have been added that have beneficial effects on the viability of the organisms and the storage stability
Glass Ceramic Formulation Data Package
International Nuclear Information System (INIS)
Crum, Jarrod V.; Rodriguez, Carmen P.; McCloy, John S.; Vienna, John D.; Chung, Chul-Woo
2012-01-01
A glass ceramic waste form is being developed for treatment of secondary waste streams generated by aqueous reprocessing of commercial used nuclear fuel (Crum et al. 2012b). The waste stream contains a mixture of transition metals, alkali, alkaline earths, and lanthanides, several of which exceed the solubility limits of a single phase borosilicate glass (Crum et al. 2009; Caurant et al. 2007). A multi-phase glass ceramic waste form allows incorporation of insoluble components of the waste by designed crystallization into durable heat tolerant phases. The glass ceramic formulation and processing targets the formation of the following three stable crystalline phases: (1) powellite (XMoO4) where X can be (Ca, Sr, Ba, and/or Ln), (2) oxyapatite Yx,Z(10-x)Si6O26 where Y is alkaline earth, Z is Ln, and (3) lanthanide borosilicate (Ln5BSi2O13). These three phases incorporate the waste components that are above the solubility limit of a single-phase borosilicate glass. The glass ceramic is designed to be a single phase melt, just like a borosilicate glass, and then crystallize upon slow cooling to form the targeted phases. The slow cooling schedule is based on the centerline cooling profile of a 2 foot diameter canister such as the Hanford High-Level Waste canister. Up to this point, crucible testing has been used for glass ceramic development, with cold crucible induction melter (CCIM) targeted as the ultimate processing technology for the waste form. Idaho National Laboratory (INL) will conduct a scaled CCIM test in FY2012 with a glass ceramic to demonstrate the processing behavior. This Data Package documents the laboratory studies of the glass ceramic composition to support the CCIM test. Pacific Northwest National Laboratory (PNNL) measured melt viscosity, electrical conductivity, and crystallization behavior upon cooling to identify a processing window (temperature range) for melter operation and cooling profiles necessary to crystallize the targeted phases in the
... Staying Safe Videos for Educators Search English Español Speech Problems KidsHealth / For Teens / Speech Problems What's in ... a person's ability to speak clearly. Some Common Speech and Language Disorders Stuttering is a problem that ...
Implicit solvers for large-scale nonlinear problems
International Nuclear Information System (INIS)
Keyes, David E; Reynolds, Daniel R; Woodward, Carol S
2006-01-01
Computational scientists are grappling with increasingly complex, multi-rate applications that couple such physical phenomena as fluid dynamics, electromagnetics, radiation transport, chemical and nuclear reactions, and wave and material propagation in inhomogeneous media. Parallel computers with large storage capacities are paving the way for high-resolution simulations of coupled problems; however, hardware improvements alone will not prove enough to enable simulations based on brute-force algorithmic approaches. To accurately capture nonlinear couplings between dynamically relevant phenomena, often while stepping over rapid adjustments to quasi-equilibria, simulation scientists are increasingly turning to implicit formulations that require a discrete nonlinear system to be solved for each time step or steady state solution. Recent advances in iterative methods have made fully implicit formulations a viable option for solution of these large-scale problems. In this paper, we overview one of the most effective iterative methods, Newton-Krylov, for nonlinear systems and point to software packages with its implementation. We illustrate the method with an example from magnetically confined plasma fusion and briefly survey other areas in which implicit methods have bestowed important advantages, such as allowing high-order temporal integration and providing a pathway to sensitivity analyses and optimization. Lastly, we overview algorithm extensions under development motivated by current SciDAC applications
Directory of Open Access Journals (Sweden)
Muhammad Aslam Noor
2004-01-01
Full Text Available We consider a new class of equilibrium problems, known as hemiequilibrium problems. Using the auxiliary principle technique, we suggest and analyze a class of iterative algorithms for solving hemiequilibrium problems, the convergence of which requires either pseudomonotonicity or partially relaxed strong monotonicity. As a special case, we obtain a new method for hemivariational inequalities. Since hemiequilibrium problems include hemivariational inequalities and equilibrium problems as special cases, the results proved in this paper still hold for these problems.
Simulation of hydrogen mitigation in catalytic recombiner. Part-II: Formulation of a CFD model
International Nuclear Information System (INIS)
Prabhudharwadkar, Deoras M.; Iyer, Kannan N.
2011-01-01
Research highlights: → Hydrogen transport in containment with recombiners is a multi-scale problem. → A novel methodology worked out to lump the recombiner characteristics. → Results obtained using commercial code FLUENT are cast in the form of correlations. → Hence, coarse grids can obtain accurate distribution of H 2 in containment. → Satisfactory working of the methodology is clearly demonstrated. - Abstract: This paper aims at formulation of a model compatible with CFD code to simulate hydrogen distribution and mitigation using a Passive Catalytic Recombiner in the Nuclear power plant containments. The catalytic recombiner is much smaller in size compared to the containment compartments. In order to fully resolve the recombination processes during the containment simulations, it requires the geometric details of the recombiner to be modelled and a very fine mesh size inside the recombiner channels. This component when integrated with containment mixing calculations would result in a large number of mesh elements which may take large computational times to solve the problem. This paper describes a method to resolve this simulation difficulty. In this exercise, the catalytic recombiner alone was first modelled in detail using the best suited option to describe the reaction rate. A detailed parametric study was conducted, from which correlations for the heat of reaction (hence the rate of reaction) and the heat transfer coefficient were obtained. These correlations were then used to model the recombiner channels as single computational cells providing necessary volumetric sources/sinks to the energy and species transport equations. This avoids full resolution of these channels, thereby allowing larger mesh size in the recombiners. The above mentioned method was successfully validated using both steady state and transient test problems and the results indicate very satisfactory modelling of the component.
A New Resistance Formulation for Carbon Nanotubes
Directory of Open Access Journals (Sweden)
Ji-Huan He
2008-01-01
Full Text Available A new resistance formulation for carbon nanotubes is suggested using fractal approach. The new formulation is also valid for other nonmetal conductors including nerve fibers, conductive polymers, and molecular wires. Our theoretical prediction agrees well with experimental observation.
Advanced Query Formulation in Deductive Databases.
Niemi, Timo; Jarvelin, Kalervo
1992-01-01
Discusses deductive databases and database management systems (DBMS) and introduces a framework for advanced query formulation for end users. Recursive processing is described, a sample extensional database is presented, query types are explained, and criteria for advanced query formulation from the end user's viewpoint are examined. (31…
Aerosol formulation and clinical efficacy of bronchodilators
Zanen, Pieter
1998-01-01
This thesis subject is the improvement of the formulation of inhaled aerosols. It is well known that the formulation of inhaled drugs is not optimal: the major part of the mass delivered does not reach the lower airways. This phenomenon is due to the particle size of the inhaled particles, which
Lattice formulations of reggeon interactions
International Nuclear Information System (INIS)
Brower, R.C.; Ellis, J.; Savit, R.; Zinn-Justin, J.
1976-01-01
A class of lattice analogues to reggeon field theory is examined. First the transition from a continuum to a lattice field theory is discussed, emphasizing the necessity of a Wick rotation and the consideration of symmetry properties. Next the theory is transformed to a discrete system with two spins at each lattice site, and the problems of the triple-reggeon interaction and the reggeon energy gap are discussed. It is pointed out that transferring the theory from the continuum to a lattice necesarily introduces new relevant operators not normally present in reggeon field theory. (Auth.)
Undefined cellulase formulations hinder scientific reproducibility.
Himmel, Michael E; Abbas, Charles A; Baker, John O; Bayer, Edward A; Bomble, Yannick J; Brunecky, Roman; Chen, Xiaowen; Felby, Claus; Jeoh, Tina; Kumar, Rajeev; McCleary, Barry V; Pletschke, Brett I; Tucker, Melvin P; Wyman, Charles E; Decker, Stephen R
2017-01-01
In the shadow of a burgeoning biomass-to-fuels industry, biological conversion of lignocellulose to fermentable sugars in a cost-effective manner is key to the success of second-generation and advanced biofuel production. For the effective comparison of one cellulase preparation to another, cellulase assays are typically carried out with one or more engineered cellulase formulations or natural exoproteomes of known performance serving as positive controls. When these formulations have unknown composition, as is the case with several widely used commercial products, it becomes impossible to compare or reproduce work done today to work done in the future, where, for example, such preparations may not be available. Therefore, being a critical tenet of science publishing, experimental reproducibility is endangered by the continued use of these undisclosed products. We propose the introduction of standard procedures and materials to produce specific and reproducible cellulase formulations. These formulations are to serve as yardsticks to measure improvements and performance of new cellulase formulations.
Introducing radiality constraints in capacitated location-routing problems
Directory of Open Access Journals (Sweden)
Eliana Mirledy Toro Ocampo
2017-03-01
Full Text Available In this paper, we introduce a unified mathematical formulation for the Capacitated Vehicle Routing Problem (CVRP and for the Capacitated Location Routing Problem (CLRP, adopting radiality constraints in order to guarantee valid routes and eliminate subtours. This idea is inspired by formulations already employed in electric power distribution networks, which requires a radial topology in its operation. The results show that the proposed formulation greatly improves the convergence of the solver.
Jalali-Heravi, Mehdi; Moazeni-Pourasil, Roudabeh Sadat; Sereshti, Hassan
2015-03-01
In analysis of complex natural matrices by gas chromatography-mass spectrometry (GC-MS), many disturbing factors such as baseline drift, spectral background, homoscedastic and heteroscedastic noise, peak shape deformation (non-Gaussian peaks), low S/N ratio and co-elution (overlapped and/or embedded peaks) lead the researchers to handle them to serve time, money and experimental efforts. This study aimed to improve the GC-MS analysis of complex natural matrices utilizing multivariate curve resolution (MCR) methods. In addition, to assess the peak purity of the two-dimensional data, a method called variable size moving window-evolving factor analysis (VSMW-EFA) is introduced and examined. The proposed methodology was applied to the GC-MS analysis of Iranian Lavender essential oil, which resulted in extending the number of identified constituents from 56 to 143 components. It was found that the most abundant constituents of the Iranian Lavender essential oil are α-pinene (16.51%), camphor (10.20%), 1,8-cineole (9.50%), bornyl acetate (8.11%) and camphene (6.50%). This indicates that the Iranian type Lavender contains a relatively high percentage of α-pinene. Comparison of different types of Lavender essential oils showed the composition similarity between Iranian and Italian (Sardinia Island) Lavenders. Published by Elsevier B.V.
Generalized formulation of free energy and application to photosynthesis
Zhang, Hwe Ik; Choi, M. Y.
2018-03-01
The origin of free energy on the earth is solar radiation. However, the amount of free energy it contains has seldom been investigated, because the free energy concept was believed to be inappropriate for a system of photons. Instead, the origin of free energy has been sought in the process of photosynthesis, imposing a limit of conversion given by the Carnot efficiency. Here we present a general formulation, capable of not only assessing accurately the available amount of free energy in the photon gas but also explaining the primary photosynthetic process more succinctly. In this formulation, the problem of "photosynthetic conversion of the internal energy of photons into the free energy of chlorophyll" is replaced by simple "free energy transduction" between the photons and chlorophyll. An analytic expression for the photosynthetic efficiency is derived and shown to deviate from the Carnot efficiency. Some predictions verifiable possibly by observation are also suggested.
High Order Tensor Formulation for Convolutional Sparse Coding
Bibi, Adel Aamer
2017-12-25
Convolutional sparse coding (CSC) has gained attention for its successful role as a reconstruction and a classification tool in the computer vision and machine learning community. Current CSC methods can only reconstruct singlefeature 2D images independently. However, learning multidimensional dictionaries and sparse codes for the reconstruction of multi-dimensional data is very important, as it examines correlations among all the data jointly. This provides more capacity for the learned dictionaries to better reconstruct data. In this paper, we propose a generic and novel formulation for the CSC problem that can handle an arbitrary order tensor of data. Backed with experimental results, our proposed formulation can not only tackle applications that are not possible with standard CSC solvers, including colored video reconstruction (5D- tensors), but it also performs favorably in reconstruction with much fewer parameters as compared to naive extensions of standard CSC to multiple features/channels.
An ayurvedic formulation Sankat Mochan: A potent anthelmintic medicine
Directory of Open Access Journals (Sweden)
Khomendra Kumar Sarwa
2017-01-01
Full Text Available Aim and Object: Sankat Mochan is an ayurvedic formulation used in the urban and rural area of India. This polyherbal formulation is used for general stomach problems including abdominal cramping and diarrhea. The present investigation evaluated the anthelmintic activity of an aqueous solution of an ayurvedic medicine Sankat Mochan. Materials and Method: Various concentrations (1%, 5%, and 10% of medicine were used for anthelmintic activity on Pheretima posthuma. Piperazine citrate (10 mg/ml was used as a reference standard and distilled water as a control. Result and Conclusion: The result showed that the Sankat Mochan possess anthelmintic activity more potent than that of piperazine citrate. Thus, Sankat Mochan may be used as a potent anthelmintic agent against helminthiasis.
Refining stability and dissolution rate of amorphous drug formulations
DEFF Research Database (Denmark)
Grohganz, Holger; Priemel, Petra A; Löbmann, Korbinian
2014-01-01
Introduction: Poor aqueous solubility of active pharmaceutical ingredients (APIs) is one of the main challenges in the development of new small molecular drugs. Additionally, the proportion of poorly soluble drugs among new chemical entities is increasing. The transfer of a crystalline drug to its...... and on the interaction of APIs with small molecular compounds rather than polymers. Finally, in situ formation of an amorphous form might be an option to avoid storage problems altogether. Expert opinion: The diversity of poorly soluble APIs formulated in an amorphous drug delivery system will require different...... approaches for their stabilisation. Thus, increased focus on emerging techniques can be expected and a rational approach to decide the correct formulation is needed....
On the fairlie's Moyal formulation of M(atrix)-theory
International Nuclear Information System (INIS)
Hssaini, M.; Sedra, M.B.; Bennai, M.; Maroufi, B.
2000-07-01
Starting from the Moyal formulation of M-theory in the large N-limit, we propose to reexamine the associated membrane equations of motion in 10 dimensions formulated in terms of Poisson bracket. Among the results obtained, we rewrite the coupled first order Nahm's equations into a simple form leading in turn to their systematic relation with SU(∞) Yang Mills equations of motion. The former are interpreted as the vanishing condition of some conserved currents which we propose. We also develop an algebraic analysis in which an ansatz is considered and find an explicit form for the membrane solution of our problem. Typical solutions known in literature can also emerge as special cases of the proposed solution. (author)
Giacoia, George P; Taylor-Zapata, Perdita; Mattison, Donald
2007-01-01
The development and compounding of pharmacotherapeutic formulations that are suitable for infants and young children can be a challenging problem. This problem results from the lack of knowledge on the acceptability of different dosage forms and formulations to children in relation to age and developmental status, as well as the lack of reliable documentation of formulations used in pediatric clinical trials. As part of its mandate under the Best Pharmaceuticals for Children Act to improve pediatric therapeutics, the National Institute of Child Health and Human Development has sponsored the Pediatric Formulations Initiative. The goal of this ongoing initiative is to address the issues and concerns associated with pediatric therapeutics by convening groups of researchers and experts in pediatric formulations from academia, pharmaceutical companies, the National Institutes of Health, and the U.S. Food and Drug Administration. In this second part of a two-part article, the activities of the various groups that constitute the Pediatric Formulations Initiative are discussed, in addition the Initiative's future activities and plans are outlined.
Vantage point - A 'wicked' problem.
Naish, Jane
2015-10-01
SENIOR NURSES everywhere are facing a 'wicked' problem, wicked in the sense that it seems to defy resolution. The problem is this: the national shortage of nurses, particularly of those at band 5, is forcing us to use agency nurses so that we have enough staff to provide patient care safely.
Contribution of Fuzzy Minimal Cost Flow Problem by Possibility Programming
S. Fanati Rashidi; A. A. Noora
2010-01-01
Using the concept of possibility proposed by zadeh, luhandjula ([4,8]) and buckley ([1]) have proposed the possibility programming. The formulation of buckley results in nonlinear programming problems. Negi [6]re-formulated the approach of Buckley by the use of trapezoidal fuzzy numbers and reduced the problem into fuzzy linear programming problem. Shih and Lee ([7]) used the Negi approach to solve a minimum cost flow problem, whit fuzzy costs and the upper and lower bound. ...
An efficient formulation for linear and geometric non-linear membrane elements
Directory of Open Access Journals (Sweden)
Mohammad Rezaiee-Pajand
Full Text Available Utilizing the straingradient notation process and the free formulation, an efficient way of constructing membrane elements will be proposed. This strategy can be utilized for linear and geometric non-linear problems. In the suggested formulation, the optimization constraints of insensitivity to distortion, rotational invariance and not having parasitic shear error are employed. In addition, the equilibrium equations will be established based on some constraints among the strain states. The authors' technique can easily separate the rigid body motions, and those belong to deformational motions. In this article, a novel triangular element, named SST10, is formulated. This element will be used in several plane problems having irregular mesh and complicated geometry with linear and geometrically nonlinear behavior. The numerical outcomes clearly demonstrate the efficiency of the new formulation.
Boundary-integral equation formulation for time-dependent inelastic deformation in metals
Energy Technology Data Exchange (ETDEWEB)
Kumar, V; Mukherjee, S
1977-01-01
The mathematical structure of various constitutive relations proposed in recent years for representing time-dependent inelastic deformation behavior of metals at elevated temperatues has certain features which permit a simple formulation of the three-dimensional inelasticity problem in terms of real time rates. A direct formulation of the boundary-integral equation method in terms of rates is discussed for the analysis of time-dependent inelastic deformation of arbitrarily shaped three-dimensional metallic bodies subjected to arbitrary mechanical and thermal loading histories and obeying constitutive relations of the kind mentioned above. The formulation is based on the assumption of infinitesimal deformations. Several illustrative examples involving creep of thick-walled spheres, long thick-walled cylinders, and rotating discs are discussed. The implementation of the method appears to be far easier than analogous BIE formulations that have been suggested for elastoplastic problems.
Polymer Formulations for Cartilage Repair
Energy Technology Data Exchange (ETDEWEB)
Gutowska, Anna; Jasionowski, Marek; Morris, J. E.; Chrisler, William B.; An, Yuehuei H.; Mironov, V.
2001-05-15
Regeneration of destroyed articular cartilage can be induced by transplantation of cartilage cells into a defect. The best results are obtained with the use of autologus cells. However, obtaining large amounts of autologus cartilage cells causes a problem of creating a large cartilage defect in a donor site. Techniques are currently being developed to harvest a small number of cells and propagate them in vitro. It is a challenging task, however, due to the fact that ordinarily, in a cell culture on flat surfaces, chondrocytes do not maintain their in vivo phenotype and irreversibly diminish or cease the synthesis of aggregating proteoglycans. Therefore, the research is continuing to develop culture conditions for chondrocytes with the preserved phenotype.
Linearized inversion frameworks toward high-resolution seismic imaging
Aldawood, Ali
2016-09-01
Seismic exploration utilizes controlled sources, which emit seismic waves that propagate through the earth subsurface and get reflected off subsurface interfaces and scatterers. The reflected and scattered waves are recorded by recording stations installed along the earth surface or down boreholes. Seismic imaging is a powerful tool to map these reflected and scattered energy back to their subsurface scattering or reflection points. Seismic imaging is conventionally based on the single-scattering assumption, where only energy that bounces once off a subsurface scatterer and recorded by a receiver is projected back to its subsurface position. The internally multiply scattered seismic energy is considered as unwanted noise and is usually suppressed or removed from the recorded data. Conventional seismic imaging techniques yield subsurface images that suffer from low spatial resolution, migration artifacts, and acquisition fingerprint due to the limited acquisition aperture, number of sources and receivers, and bandwidth of the source wavelet. Hydrocarbon traps are becoming more challenging and considerable reserves are trapped in stratigraphic and pinch-out traps, which require highly resolved seismic images to delineate them. This thesis focuses on developing and implementing new advanced cost-effective seismic imaging techniques aiming at enhancing the resolution of the migrated images by exploiting the sparseness of the subsurface reflectivity distribution and utilizing the multiples that are usually neglected when imaging seismic data. I first formulate the seismic imaging problem as a Basis pursuit denoise problem, which I solve using an L1-minimization algorithm to obtain the sparsest migrated image corresponding to the recorded data. Imaging multiples may illuminate subsurface zones, which are not easily illuminated by conventional seismic imaging using primary reflections only. I then develop an L2-norm (i.e. least-squares) inversion technique to image
Formulation of heat absorbing glasses
Directory of Open Access Journals (Sweden)
Álvarez-Casariego, Pedro
1996-06-01
Full Text Available In the thermal exchanges between buildings and environment, glazing is an element of major importance, for it largely influences the so-called Solar Heat Gain and Thermal Losses. These parameters can be modified by applying different type of coatings onto glass surface or by adding colorant compounds during glass melting.
The latter is a cheaper way to control the Solar Heat Gain. The knowledge of the laws governing the interaction between colorant compounds and solar radiation, allows us to define glass formulations achieving specific aesthetic requirements and solar energy absorption.
In this paper two examples of application of the modelling of glass colorants spectral absorptance are presented. First is addressed to obtaining a glass with high luminous transmittance and low solar energy transmittance, and the other one to obtaining a glass with neutral colour appearance and minimized solar energy transmittance. Calculation formulas are defined together with photometric properties so-obtained. These type of glasses are particularly suitable to be used as building and automotive glazing, for they retain the mechanical characteristics and possibilities of transformation of standard glass.
En los intercambios de energía entre un edificio y el medio exterior, el vidrio es el elemento de mayor importancia, por su influencia en la Ganancia de Calor Solar y en las Pérdidas Térmicas. Estos parámetros pueden ser modificados mediante el depósito de capas sobre el vidrio o mediante la adición de compuestos absorbentes de la radiación solar.
Esta última vía es la más económica para controlar la Ganancia de Calor Solar. El conocimiento de las leyes que gobiernan la interacción de los diversos colorantes con la radiación solar, permite definir formulaciones de vidrios con características especificas de tipo estético y de absorción energética.
En este trabajo se presentan dos ejemplos de aplicación de esta modelización de las
Operator formulation of the droplet model
International Nuclear Information System (INIS)
Lee, B.W.
1987-01-01
We study in detail the implications of the operator formulation of the droplet model. The picture of high-energy scattering that emerges from this model attributed the interaction between two colliding particles at high energies to an instantaneous, multiple exchange between two extended charge distributions. Thus the study of charge correlation functions becomes the most important problem in the droplet model. We find that in order for the elastic cross section to have a finite limit at infinite energy, the charge must be a conserved one. In quantum electrodynamics the charge in question is the electric charge. In hadronic physics, we conjecture, it is the baryonic charge. Various arguments for and implications of this hypothesis are presented. We study formal properties of the charge correlation functions that follow from microcausality, T, C, P invariances, and charge conservation. Perturbation expansion of the correlation functions is studied, and their cluster properties are deduced. A cluster expansion of the high-energy T matrix is developed, and the exponentiation of the interaction potential in this scheme is noted. The operator droplet model is put to the test of reproducing the high-energy limit of elastic scattering quantum electrodynamics found by Cheng and Wu in perturbation theory. We find that the droplet model reproduces exactly the results of Cheng and Wu as to the impact factor. In fact, the ''impact picture'' of Cheng and Wu is completely equivalent to the droplet model in the operator version. An appraisal is made of the possible limitation of the model. (author). 13 refs
FORMULATION OF INDONESIAN PUBLIC HEALTH DEVELOPMENT INDEX
Directory of Open Access Journals (Sweden)
Puti Sari Hidayangsih
2012-11-01
Full Text Available The objective of formulation the Indonesian Public Health Development Index (IPHDI was to describe the successful development of public health based on composite several community-based health indicators. Cross sectional study design.The data analyzed was a combination of a nationwide survey covering Baseline Health Research (Riskesdas 2007, National Social Economic Survey (Susenas 2007 and the Village Potential (Podes in 2008. Selection of appropriate indicators included in IPHDI associated with LE at birth, selected on the basis of consensus expert team. When the indicator has the RSE (relative standard error value of less than 30% and the value was held for more than 75% of districts. then the indicator is a candidate in the calculation IPHDI. The team doing the analysis on 22 models of the combination of indicators. The number of indicators chat involved between 18 to 24. These models have been made and tested for correlation weighting of life expectancy each district. Results of correlation ranged from 0.314 to 0.512 and all models have a significance value p< 0.001. The model was chosen considering the variables that are considered priorities and values of correlation. IPHDI Highest value is 0.708959 (Magelang City, Central Java and the lowest is 0.247059 (Pegunungan Bintang district, Papua. Conclusion. IPHDI utilization is to know district who has severe health problems, resulting in enhancement programs that have intervened, resulting in focusing the target location, and became one of the parameters for the calculation of aid allocations fairly from center to the region. Key words: health indicators, Indonesian public health development index, life expectancy
International Nuclear Information System (INIS)
Seiler, E.
1985-01-01
Confinement of quarks is sometimes taken as some kind of dogma in the contemporary theory of strong interactions - quantum chromo-dynamics (QCD). Scientists should not be content with that. What is meant by ''permanent confinement'' should be formulated more precisely to see whether the theory has this property or not. The author looks at some possible interpretations of ''confinement'' and their shortcomings and then turns to the most widely used rather pragmatic definition based on the somewhat unphysical notion of infinitely heavy external sources. He describes what is known about the problem and tries to bring into focus some aspects that are insufficiently understood in his opinion
A comprehensive formulation for volumetric modulated arc therapy planning
Energy Technology Data Exchange (ETDEWEB)
Nguyen, Dan; Lyu, Qihui; Ruan, Dan; O’Connor, Daniel; Low, Daniel A.; Sheng, Ke, E-mail: ksheng@mednet.ucla.edu [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California 90024 (United States)
2016-07-15
Purpose: Volumetric modulated arc therapy (VMAT) is a widely employed radiation therapy technique, showing comparable dosimetry to static beam intensity modulated radiation therapy (IMRT) with reduced monitor units and treatment time. However, the current VMAT optimization has various greedy heuristics employed for an empirical solution, which jeopardizes plan consistency and quality. The authors introduce a novel direct aperture optimization method for VMAT to overcome these limitations. Methods: The comprehensive VMAT (comVMAT) planning was formulated as an optimization problem with an L2-norm fidelity term to penalize the difference between the optimized dose and the prescribed dose, as well as an anisotropic total variation term to promote piecewise continuity in the fluence maps, preparing it for direct aperture optimization. A level set function was used to describe the aperture shapes and the difference between aperture shapes at adjacent angles was penalized to control MLC motion range. A proximal-class optimization solver was adopted to solve the large scale optimization problem, and an alternating optimization strategy was implemented to solve the fluence intensity and aperture shapes simultaneously. Single arc comVMAT plans, utilizing 180 beams with 2° angular resolution, were generated for a glioblastoma multiforme case, a lung (LNG) case, and two head and neck cases—one with three PTVs (H&N{sub 3PTV}) and one with foue PTVs (H&N{sub 4PTV})—to test the efficacy. The plans were optimized using an alternating optimization strategy. The plans were compared against the clinical VMAT (clnVMAT) plans utilizing two overlapping coplanar arcs for treatment. Results: The optimization of the comVMAT plans had converged within 600 iterations of the block minimization algorithm. comVMAT plans were able to consistently reduce the dose to all organs-at-risk (OARs) as compared to the clnVMAT plans. On average, comVMAT plans reduced the max and mean OAR dose by 6
Explaining the Mind: Problems, Problems
Harnad, Stevan
2001-01-01
The mind/body problem is the feeling/function problem: How and why do feeling systems feel? The problem is not just "hard" but insoluble (unless one is ready to resort to telekinetic dualism). Fortunately, the "easy" problems of cognitive science (such as the how and why of categorization and language) are not insoluble. Five books (by Damasio, Edelman/Tononi...
Simultaneous super-resolution and blind deconvolution
International Nuclear Information System (INIS)
Sroubek, F; Flusser, J; Cristobal, G
2008-01-01
In many real applications, blur in input low-resolution images is a nuisance, which prevents traditional super-resolution methods from working correctly. This paper presents a unifying approach to the blind deconvolution and superresolution problem of multiple degraded low-resolution frames of the original scene. We introduce a method which assumes no prior information about the shape of degradation blurs and which is properly defined for any rational (fractional) resolution factor. The method minimizes a regularized energy function with respect to the high-resolution image and blurs, where regularization is carried out in both the image and blur domains. The blur regularization is based on a generalized multichannel blind deconvolution constraint. Experiments on real data illustrate robustness and utilization of the method
AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING
Directory of Open Access Journals (Sweden)
В. Харченко
2011-02-01
Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict resolution by course maneuvering has been developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done
Canonical operator formulation of nonequilibrium thermodynamics
International Nuclear Information System (INIS)
Mehrafarin, M.
1992-09-01
A novel formulation of nonequilibrium thermodynamics is proposed which emphasises the fundamental role played by the Boltzmann constant k in fluctuations. The equivalence of this and the stochastic formulation is demonstrated. The k → 0 limit of this theory yields the classical deterministic description of nonequilibrium thermodynamics. The new formulation possesses unique features which bear two important results namely the thermodynamic uncertainty principle and the quantisation of entropy production rate. Such a theory becomes indispensable whenever fluctuations play a significant role. (author). 7 refs
Application of UV Imaging in Formulation Development
DEFF Research Database (Denmark)
Sun, Yu; Østergaard, Jesper
2017-01-01
defining formulation behavior after exposure to the aqueous environments and pharmaceutical performance is critical in pharmaceutical development, manufacturing and quality control of drugs. UV imaging has been explored as a tool for qualitative and quantitative characterization of drug dissolution...... related to the structural properties of the drug substance or formulation can be monitored. UV imaging is a non-intrusive and simple-to-operate analytical technique which holds potential for providing a mechanistic foundation for formulation development. This review aims to cover applications of UV...
Formulation of 11-dimensional supergravity in superspace
International Nuclear Information System (INIS)
Cremmer, E.; Ferrara, S.
1980-01-01
We formulate on-shell 11-dimensional supergravity in superspace and express its equations of motion in terms of purely geometrical quantities. All torsion and curvature components are solved in terms of a single superfield Wsub(rstu), totally antisymmetric in its (flat vector) indices. The dimensional reduction of this formulation is expected to be related to the superspace formulation of N = 8 extended supergravity and might explain the origin of the hidden (local) SU(8) and (global) E 7 symmetries present in this theory. (orig.)
Some problems of relativistic electrodynamics
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1991-01-01
Some problems of electrodynamics are considered from the point of view of the radar formulation of relativity theory. This formulation is based on light or retarded distances, the increasing of longitudinal sizes of moving objects is its consequence ( e longation formula ) . Based of Lienard-Wiechert potentials it is shown that in terms of retarded distances equipotential surfaces take the form of rotation ellipsoids, stretched in the direction of electric charge motion. The difficulty connected with the appearance of charge in a moving (neutral) current-carrying conductor is overcome. 23 refs.; 4 figs
A new continuous-time formulation for scheduling crude oil operations
International Nuclear Information System (INIS)
Reddy, P. Chandra Prakash; Karimi, I.A.; Srinivasan, R.
2004-01-01
In today's competitive business climate characterized by uncertain oil markets, responding effectively and speedily to market forces, while maintaining reliable operations, is crucial to a refinery's bottom line. Optimal crude oil scheduling enables cost reduction by using cheaper crudes intelligently, minimizing crude changeovers, and avoiding ship demurrage. So far, only discrete-time formulations have stood up to the challenge of this important, nonlinear problem. A continuous-time formulation would portend numerous advantages, however, existing work in this area has just begun to scratch the surface. In this paper, we present the first complete continuous-time mixed integer linear programming (MILP) formulation for the short-term scheduling of operations in a refinery that receives crude from very large crude carriers via a high-volume single buoy mooring pipeline. This novel formulation accounts for real-world operational practices. We use an iterative algorithm to eliminate the crude composition discrepancy that has proven to be the Achilles heel for existing formulations. While it does not guarantee global optimality, the algorithm needs only MILP solutions and obtains excellent maximum-profit schedules for industrial problems with up to 7 days of scheduling horizon. We also report the first comparison of discrete- vs. continuous-time formulations for this complex problem. (Author)
Approximation of Bayesian Inverse Problems for PDEs
Cotter, S. L.; Dashti, M.; Stuart, A. M.
2010-01-01
Inverse problems are often ill posed, with solutions that depend sensitively on data.n any numerical approach to the solution of such problems, regularization of some form is needed to counteract the resulting instability. This paper is based on an approach to regularization, employing a Bayesian formulation of the problem, which leads to a notion of well posedness for inverse problems, at the level of probability measures. The stability which results from this well posedness may be used as t...
Environmental Systems Conflict Resolution
Hipel, K. W.
2017-12-01
more DMs in order for a desirable resolution to be reached. In the behavioral engine problem, the manner in which a DM may be thinking strategically under conflict can be calculated given the input preferences and a selected equilibrium.
Mathematical Formulation of Multilayer Networks
De Domenico, Manlio; Solé-Ribalta, Albert; Cozzo, Emanuele; Kivelä, Mikko; Moreno, Yamir; Porter, Mason A.; Gómez, Sergio; Arenas, Alex
2013-10-01
A network representation is useful for describing the structure of a large variety of complex systems. However, most real and engineered systems have multiple subsystems and layers of connectivity, and the data produced by such systems are very rich. Achieving a deep understanding of such systems necessitates generalizing “traditional” network theory, and the newfound deluge of data now makes it possible to test increasingly general frameworks for the study of networks. In particular, although adjacency matrices are useful to describe traditional single-layer networks, such a representation is insufficient for the analysis and description of multiplex and time-dependent networks. One must therefore develop a more general mathematical framework to cope with the challenges posed by multilayer complex systems. In this paper, we introduce a tensorial framework to study multilayer networks, and we discuss the generalization of several important network descriptors and dynamical processes—including degree centrality, clustering coefficients, eigenvector centrality, modularity, von Neumann entropy, and diffusion—for this framework. We examine the impact of different choices in constructing these generalizations, and we illustrate how to obtain known results for the special cases of single-layer and multiplex networks. Our tensorial approach will be helpful for tackling pressing problems in multilayer complex systems, such as inferring who is influencing whom (and by which media) in multichannel social networks and developing routing techniques for multimodal transportation systems.
On Resolution Complexity of Matching Principles
DEFF Research Database (Denmark)
Dantchev, Stefan S.
proof system. The results in the thesis fall in this category. We study the Resolution complexity of some Matching Principles. The three major contributions of the thesis are as follows. Firstly, we develop a general technique of proving resolution lower bounds for the perfect matchingprinciples based...... Chessboard as well as for Tseitin tautologies based on rectangular grid graph. We reduce these problems to Tiling games, a concept introduced by us, which may be of interest on its own. Secondly, we find the exact Tree-Resolution complexity of the Weak Pigeon-Hole Principle. It is the most studied...
OTTER, Resolution Style Theorem Prover
International Nuclear Information System (INIS)
McCune, W.W.
2001-01-01
1 - Description of program or function: OTTER (Other Techniques for Theorem-proving and Effective Research) is a resolution-style theorem-proving program for first-order logic with equality. OTTER includes the inference rules binary resolution, hyper-resolution, UR-resolution, and binary para-modulation. These inference rules take as small set of clauses and infer a clause. If the inferred clause is new and useful, it is stored and may become available for subsequent inferences. Other capabilities are conversion from first-order formulas to clauses, forward and back subsumption, factoring, weighting, answer literals, term ordering, forward and back demodulation, and evaluable functions and predicates. 2 - Method of solution: For its inference process OTTER uses the given-clause algorithm, which can be viewed as a simple implementation of the set of support strategy. OTTER maintains three lists of clauses: axioms, sos (set of support), and demodulators. OTTER is not automatic. Even after the user has encoded a problem into first-order logic or into clauses, the user must choose inference rules, set options to control the processing of inferred clauses, and decide which input formulae or clauses are to be in the initial set of support and which, if any, equalities are to be demodulators. If OTTER fails to find a proof, the user may try again different initial conditions. 3 - Restrictions on the complexity of the problem - Maxima of: 5000 characters in an input string, 64 distinct variables in a clause, 51 characters in any symbol. The maxima can be changed by finding the appropriate definition in the header.h file, increasing the limit, and recompiling OTTER. There are a few constraints on the order of commands
An extension of implicit Monte Carlo diffusion: Multigroup and the difference formulation
International Nuclear Information System (INIS)
Cleveland, Mathew A.; Gentile, Nick A.; Palmer, Todd S.
2010-01-01
Implicit Monte Carlo (IMC) and Implicit Monte Carlo Diffusion (IMD) are approaches to the numerical solution of the equations of radiative transfer. IMD was previously derived and numerically tested on grey, or frequency-integrated problems . In this research, we extend Implicit Monte Carlo Diffusion (IMD) to account for frequency dependence, and we implement the difference formulation as a source manipulation variance reduction technique. We derive the relevant probability distributions and present the frequency dependent IMD algorithm, with and without the difference formulation. The IMD code with and without the difference formulation was tested using both grey and frequency dependent benchmark problems. The Su and Olson semi-analytic Marshak wave benchmark was used to demonstrate the validity of the code for grey problems . The Su and Olson semi-analytic picket fence benchmark was used for the frequency dependent problems . The frequency dependent IMD algorithm reproduces the results of both Su and Olson benchmark problems. Frequency group refinement studies indicate that the computational cost of refining the group structure is likely less than that of group refinement in deterministic solutions of the radiation diffusion methods. Our results show that applying the difference formulation to the IMD algorithm can result in an overall increase in the figure of merit for frequency dependent problems. However, the creation of negatively weighted particles from the difference formulation can cause significant numerical instabilities in regions of the problem with sharp spatial gradients in the solution. An adaptive implementation of the difference formulation may be necessary to focus its use in regions that are at or near thermal equilibrium.
Controlled Release Formulations of Auxinic Herbicides
Kowalski, Witold J.; Siłowiecki, Andrzej.; Romanowska, Iwona; Glazek, Mariola; Bajor, Justyna; Cieciwa, Katarzyna; Rychter, Piotr
2013-04-01
Controlled release formulations are applied extensively for the release of active ingredients such as plant protection agents and fertilizers in response to growing concern for ecological problems associated with increased use of plant protection chemicals required for intensive agricultural practices [1]. We synthesized oligomeric mixtures of (R,S)-3-hydroxy butyric acid chemically bonded with 2,4-D, Dicamba and MCPA herbicides (HBA) respectively, and determined their molecular structure and molecular weight dispersion by the size exclusion chromatography, proton magnetic resonance spectrometry and electro-spray ionization mass spectrometry. Further we carried out bioassays of herbicidal effectiveness of the HBA herbicides vs. series of dicotyledonous weeds and crop injury tests [2, 3, 4]. Field bioassays were accomplished according to the EPPO standards [5]. Groups of representative weeds (the development stages in the BCCH scale: 10 - 30) were selected as targets. Statistical variabilities were assessed by the Fisher LSD test for plants treated with the studied herbicides in form of HBA oligomers, the reference herbicides in form of dimethyl ammonium salts (DMA), and untreated plants. No statistically significant differences in the crop injuries caused by the HBA vs. the DMA reference formulation were observed. The effectiveness of the HBA herbicides was lower through the initial period (ca. 2 weeks) relative to the DMA salts, but a significant increase in the effectiveness of the HBA systems followed during the remaining fraction of each assay. After 6 weeks all observed efficiencies approached 100%. The death of weeds treated with the HBA herbicides was delayed when compared with the DMA reference herbicides. The delayed uptake observed for the HBA oligomers relative to the DMA salts was due to controlled release phenomena. In case of the DMA salts the total amount of active ingredients was available at the target site. By contrast, the amount of an active
Chemical-Based Formulation Design: Virtual Experimentation
DEFF Research Database (Denmark)
Conte, Elisa; Gani, Rafiqul
This paper presents a software, the virtual Product-Process Design laboratory (virtual PPD-lab) and the virtual experimental scenarios for design/verification of consumer oriented liquid formulated products where the software can be used. For example, the software can be employed for the design......, the additives and/or their mixtures (formulations). Therefore, the experimental resources can focus on a few candidate product formulations to find the best product. The virtual PPD-lab allows various options for experimentations related to design and/or verification of the product. For example, the selection...... design, model adaptation). All of the above helps to perform virtual experiments by blending chemicals together and observing their predicted behaviour. The paper will highlight the application of the virtual PPD-lab in the design and/or verification of different consumer products (paint formulation...
Understanding Pesticide Risks: Toxicity and Formulation
Muntz, Helen; Miller, Rhonda; Alston, Diane
2016-01-01
This fact sheet provides information about pesticide risks to human health, primary means of pesticide exposure, standardized measures of pesticide toxicity, pesticide signal words and type of pesticide formulations.
Emulsifying Formulation of Rosuvastatin Calcium for Improved ...
African Journals Online (AJOL)
solubility study, liquid formulations were prepared using LAS/Capryol 90: Maisine 35-1 as oil phase and. Tween 20 with ... evaluated for globule size, zeta potential, and emulsion properties. ..... surfactants which decreases the electrostatic.
Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives
Directory of Open Access Journals (Sweden)
Kunikazu Moribe
2011-01-01
Full Text Available Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate.
Formulation of Thermosensitive Hydrogel Containing Cyclodextrin ...
African Journals Online (AJOL)
Materials. Chitosan (deacetylation degree, DDA = 80 %) was obtained from HiMedia Laboratories Pvt. ... Sterile formulations were ... Chilled β-GP aqueous solution (sterilized through ..... generally decreasing away from the center of the tumor.
Current advances on polynomial resultant formulations
Sulaiman, Surajo; Aris, Nor'aini; Ahmad, Shamsatun Nahar
2017-08-01
Availability of computer algebra systems (CAS) lead to the resurrection of the resultant method for eliminating one or more variables from the polynomials system. The resultant matrix method has advantages over the Groebner basis and Ritt-Wu method due to their high complexity and storage requirement. This paper focuses on the current resultant matrix formulations and investigates their ability or otherwise towards producing optimal resultant matrices. A determinantal formula that gives exact resultant or a formulation that can minimize the presence of extraneous factors in the resultant formulation is often sought for when certain conditions that it exists can be determined. We present some applications of elimination theory via resultant formulations and examples are given to explain each of the presented settings.
Formulation and Characterization of Biodegradable Medicated ...
African Journals Online (AJOL)
PEG)-600, tributyl citrate, PEG-200, PEG-300, PEG-400, PEG-4000, triethyl citrate and castor oil. The gum formulations were characterized for the following parameters: texture profile analysis (TPA), biodegradation, in vitro drug release using a ...
A simplectic formulation of relativistic particle dynamics
International Nuclear Information System (INIS)
Tulczyjew, W.M.
1976-12-01
Particle mechanics is formulated in terms of symplectic relations and infinitesimal symplectic relations. Generating functions of symplectic relations are shown to be classical counterparts of Green's functions of wave mechanics. (orig.) [de
A sympletic formulation of relativistic particle dynamics
International Nuclear Information System (INIS)
Tulczyjew, W.M.
1977-01-01
Particle mechanics is formulated in terms of sympletic relations and infinitesimal symplectic relations. Generating functions of symplectic relations are shown to be classical counterparts of Green's functions of wave mechanics. (author)
Paclitaxel Albumin-stabilized Nanoparticle Formulation
This page contains brief information about paclitaxel albumin-stabilized nanoparticle formulation and a collection of links to more information about the use of this drug, research results, and ongoing clinical trials.
... know the exact cause of your prostate problem. Prostatitis The cause of prostatitis depends on whether you ... prostate problem in men older than age 50. Prostatitis If you have a UTI, you may be ...
International Nuclear Information System (INIS)
2005-01-01
This article presents the general problems as natural disasters, consequences of global climate change, public health, the danger of criminal actions, the availability to information about problems of environment
... Staying Safe Videos for Educators Search English Español Learning Problems KidsHealth / For Kids / Learning Problems What's in ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...
... Read MoreDepression in Children and TeensRead MoreBMI Calculator Ankle ProblemsFollow this chart for more information about problems that can cause ankle pain. Our trusted Symptom Checker is written and ...
International Nuclear Information System (INIS)
Minehara, E.; Kutschera, W.; Hartog, P.D.; Billquist, P.
1985-01-01
The ANL (Argonne National Laboratory) high-resolution injector has been installed to obtain higher mass resolution and higher preacceleration, and to utilize effectively the full mass range of ATLAS (Argonne Tandem Linac Accelerator System). Preliminary results of the first beam test are reported briefly. The design and performance, in particular a high-mass-resolution magnet with aberration compensation, are discussed. 7 refs., 5 figs., 2 tabs
Directory of Open Access Journals (Sweden)
N. A. Petrov
2014-01-01
Full Text Available The paper outlines the formulation and solution of the problem of an airplane trajectory control within dynamically changing flight conditions. Physical and mathematical formulation of the problem was justified and algorithms were proposed to solve it using modern automated technologies.
Pitchaiah, Gummalla; Akula, Annapurna; Chandi, Vishala
2017-01-01
Nutraceuticals help in combating some of the major health problems of the century including cancer, and 'nutraceutical formulations' have led to the new era of medicine and health. To develop different nutraceutical formulations and to assess the anticancer potential of nutraceutical formulations in N-methyl-N-nitrosourea (MNU)-induced mammary cancer in Sprague Dawley rats. Different nutraceutical formulations were prepared using fine powders of amla, apple, garlic, onion, papaya, turmeric, and wheat grass with and without cow urine distillate. Total phenolic content, acute oral toxicity, and microbial load of nutraceutical formulations were assessed. The anticancer potential of nutraceutical formulations was evaluated against MNU-induced mammary cancer in female Sprague Dawley rats. Improvement in total phenolic content was significant ( P safe to use in animals. Microbial load was within the limits. Significant longer tumor-free days ( P apple, garlic, onion, papaya, turmeric, and wheat grass with and without cow urine distillate. Total phenolic content, acute oral toxicity, and microbial load of nutraceutical formulations were assessed. The anticancer potential of nutraceutical formulations was evaluated against MNU-induced mammary cancer in female Sprague Dawley rats. Improvement in total phenolic content was observed after self-fortification process. Toxicity studies showed that the nutraceutical formulations were safe to use in animals. Microbial load was within the limits. Longer tumor-free days, lower tumor incidence, lower tumor multiplicity and tumor burden were observed for nutraceutical formulation-treated groups. This suggests that combination of whole food-based nutraceuticals acted synergistically in the prevention of mammary cancer. Further, the process of fortification enhanced the anticancer potential of nutraceutical formulations. Abbreviations used: HMNU: N-methyl-N-nitrosourea, CAM: Complementary and Alternative Medicine, NF: Nutraceutical
Nonlinear Vibration of Oscillation Systems using Frequency-Amplitude Formulation
Directory of Open Access Journals (Sweden)
A. Fereidoon
2012-01-01
Full Text Available In this paper we study the periodic solutions of free vibration of mechanical systems with third and fifth-order nonlinearity for two examples using He's Frequency-Amplitude Formulation (HFAF.The effectiveness and convenience of the method is illustrated in these examples. It will be shown that the solutions obtained with current method have a fabulous conformity with those achieved from time marching solution. HFAF is easy with powerful concepts and the high accuracy, so it can be found widely applicable in vibrations, especially strong nonlinearity oscillatory problems.
Coupled heat conduction and thermal stress formulation using explicit integration
International Nuclear Information System (INIS)
Marchertas, A.H.; Kulak, R.F.
1982-06-01
The formulation needed for the conductance of heat by means of explicit integration is presented. The implementation of these expressions into a transient structural code, which is also based on explicit temporal integration, is described. Comparisons of theoretical results with code predictions are given both for one-dimensional and two-dimensional problems. The coupled thermal and structural solution of a concrete crucible, when subjected to a sudden temperature increase, shows the history of cracking. The extent of cracking is compared with experimental data
An axisymmetric PFEM formulation for bottle forming simulation
Ryzhakov, Pavel B.
2017-01-01
A numerical model for bottle forming simulation is proposed. It is based upon the Particle Finite Element Method (PFEM) and is developed for the simulation of bottles characterized by rotational symmetry. The PFEM strategy is adapted to suit the problem of interest. Axisymmetric version of the formulation is developed and a modified contact algorithm is applied. This results in a method characterized by excellent computational efficiency and volume conservation characteristics. The model is validated. An example modelling the final blow process is solved. Bottle wall thickness is estimated and the mass conservation of the method is analysed.
A variational formulation for linear models in coupled dynamic thermoelasticity
International Nuclear Information System (INIS)
Feijoo, R.A.; Moura, C.A. de.
1981-07-01
A variational formulation for linear models in coupled dynamic thermoelasticity which quite naturally motivates the design of a numerical scheme for the problem, is studied. When linked to regularization or penalization techniques, this algorithm may be applied to more general models, namely, the ones that consider non-linear constraints associated to variational inequalities. The basic postulates of Mechanics and Thermodynamics as well as some well-known mathematical techniques are described. A thorough description of the algorithm implementation with the finite-element method is also provided. Proofs for existence and uniqueness of solutions and for convergence of the approximations are presented, and some numerical results are exhibited. (Author) [pt
On projection methods, convergence and robust formulations in topology optimization
DEFF Research Database (Denmark)
Wang, Fengwen; Lazarov, Boyan Stefanov; Sigmund, Ole
2011-01-01
alleviated using various projection methods. In this paper we show that simple projection methods do not ensure local mesh-convergence and propose a modified robust topology optimization formulation based on erosion, intermediate and dilation projections that ensures both global and local mesh-convergence.......Mesh convergence and manufacturability of topology optimized designs have previously mainly been assured using density or sensitivity based filtering techniques. The drawback of these techniques has been gray transition regions between solid and void parts, but this problem has recently been...
The Boltzmann equation in the difference formulation
Energy Technology Data Exchange (ETDEWEB)
Szoke, Abraham [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brooks III, Eugene D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-05-06
First we recall the assumptions that are needed for the validity of the Boltzmann equation and for the validity of the compressible Euler equations. We then present the difference formulation of these equations and make a connection with the time-honored Chapman - Enskog expansion. We discuss the hydrodynamic limit and calculate the thermal conductivity of a monatomic gas, using a simplified approximation for the collision term. Our formulation is more consistent and simpler than the traditional derivation.
Limitations of high dose carrier based formulations.
Yeung, Stewart; Traini, Daniela; Tweedie, Alan; Lewis, David; Church, Tanya; Young, Paul M
2018-06-10
This study was performed to investigate how increasing the active pharmaceutical ingredient (API) content within a formulation affects the dispersion of particles and the aerosol performance efficiency of a carrier based dry powder inhalable (DPI) formulation, using a custom dry powder inhaler (DPI) development rig. Five formulations with varying concentrations of API beclomethasone dipropionate (BDP) between 1% and 30% (w/w) were formulated as a multi-component carrier system containing coarse lactose and fine lactose with magnesium stearate. The morphology of the formulation and each component were investigated using scanning electron micrographs while the particle size was measured by laser diffraction. The aerosol performance, in terms of aerodynamic diameter, was assessed using the British pharmacopeia Apparatus E cascade impactor (Next generation impactor). Chemical analysis of the API was observed by high performance liquid chromatography (HPLC). Increasing the concentration of BDP in the blend resulted in increasing numbers and size of individual agglomerates and densely packed BDP multi-layers on the surface of the lactose carrier. BDP present within the multi-layer did not disperse as individual primary particles but as dense agglomerates, which led to a decrease in aerosol performance and increased percentage of BDP deposition within the Apparatus E induction port and pre-separator. As the BDP concentration in the blends increases, aerosol performance of the formulation decreases, in an inversely proportional manner. Concurrently, the percentage of API deposition in the induction port and pre-separator could also be linked to the amount of micronized particles (BDP and Micronized composite carrier) present in the formulation. The effect of such dose increase on the behaviour of aerosol dispersion was investigated to gain greater insight in the development and optimisation of higher dosed carrier-based formulations. Copyright © 2018 Elsevier B.V. All
Chemicals-Based Formulation Design: Virtual Experimentations
DEFF Research Database (Denmark)
Conte, Elisa; Gani, Rafiqul
2011-01-01
This paper presents a systematic procedure for virtual experimentations related to the design of liquid formulated products. All the experiments that need to be performed when designing a liquid formulated product (lotion), such as ingredients selection and testing, solubility tests, property mea...... on the design of an insect repellent lotion will show that the software is an essential instrument in decision making, and that it reduces time and resources since experimental efforts can be focused on one or few product alternatives....
Comments on alternate formulations for preequilibrium decay
International Nuclear Information System (INIS)
Blann, M.
1978-01-01
The physical and mathematical differences of several formulations for preequilibrium decay are discussed. Mathematical models and examples are presented or referred to in order to illustrate what the author believes to be errors in the exciton formulation as being due to improper inclusion of spectator effects. An earlier work of Gadioli et al. is reinterpreted, and quotations therein to work of the present author are corrected
Resolution enhancement of robust Bayesian pre-stack inversion in the frequency domain
Yin, Xingyao; Li, Kun; Zong, Zhaoyun
2016-10-01
AVO/AVA (amplitude variation with an offset or angle) inversion is one of the most practical and useful approaches to estimating model parameters. So far, publications on AVO inversion in the Fourier domain have been quite limited in view of its poor stability and sensitivity to noise compared with time-domain inversion. For the resolution and stability of AVO inversion in the Fourier domain, a novel robust Bayesian pre-stack AVO inversion based on the mixed domain formulation of stationary convolution is proposed which could solve the instability and achieve superior resolution. The Fourier operator will be integrated into the objective equation and it avoids the Fourier inverse transform in our inversion process. Furthermore, the background constraints of model parameters are taken into consideration to improve the stability and reliability of inversion which could compensate for the low-frequency components of seismic signals. Besides, the different frequency components of seismic signals can realize decoupling automatically. This will help us to solve the inverse problem by means of multi-component successive iterations and the convergence precision of the inverse problem could be improved. So, superior resolution compared with the conventional time-domain pre-stack inversion could be achieved easily. Synthetic tests illustrate that the proposed method could achieve high-resolution results with a high degree of agreement with the theoretical model and verify the quality of anti-noise. Finally, applications on a field data case demonstrate that the proposed method could obtain stable inversion results of elastic parameters from pre-stack seismic data in conformity with the real logging data.
A Resolution Prover for Coalition Logic
Directory of Open Access Journals (Sweden)
Cláudia Nalon
2014-04-01
Full Text Available We present a prototype tool for automated reasoning for Coalition Logic, a non-normal modal logic that can be used for reasoning about cooperative agency. The theorem prover CLProver is based on recent work on a resolution-based calculus for Coalition Logic that operates on coalition problems, a normal form for Coalition Logic. We provide an overview of coalition problems and of the resolution-based calculus for Coalition Logic. We then give details of the implementation of CLProver and present the results for a comparison with an existing tableau-based solver.
A minimalist functional group (MFG) approach for surrogate fuel formulation
Abdul Jameel, Abdul Gani; Naser, Nimal; Issayev, Gani; Touitou, Jamal; Ghosh, Manik Kumer; Emwas, Abdul-Hamid M.; Farooq, Aamir; Dooley, Stephen; Sarathy, Mani
2018-01-01
Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions
A minimalist functional group (MFG) approach for surrogate fuel formulation
Abdul Jameel, Abdul Gani
2018-03-20
Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions
The coevent formulation of quantum theory
International Nuclear Information System (INIS)
Wallden, Petros
2013-01-01
Understanding quantum theory has been a subject of debate from its birth. Many different formulations and interpretations have been proposed. Here we examine a recent novel formulation, namely the coevents formulation. It is a histories formulation and has as starting point the Feynman path integral and the decoherence functional. The new ontology turns out to be that of a coarse-grained history. We start with a quantum measure defined on the space of histories, and the existence of zero covers rules out single-history as potential reality (the Kochen Specker theorem casted in histories form is a special case of a zero cover). We see that allowing coarse-grained histories as potential realities avoids the previous paradoxes, maintains deductive non-contextual logic (alas non-Boolean) and gives rise to a unique classical domain. Moreover, we can recover the probabilistic predictions of quantum theory with the use of the Cournot's principle. This formulation, being both a realist formulation and based on histories, is well suited conceptually for the purposes of quantum gravity and cosmology.
An herbal formulation for hemorrhoids treatment
Directory of Open Access Journals (Sweden)
S. Dehdari
2017-11-01
Full Text Available Background and objectives: Hemorrhoids is the most painful rectal disease. Straining and pregnancy seem playing chief roles in the development of hemorrhoids. Symptoms of hemorrhoids may include bleeding, inflammation and pain. Despite current medical efforts, many discomforts of hemorrhoids have not been handled. The aim of the present study was to formulate and evaluate Itrifal-e muqil (IM tablet to achieve desired pharmaceutical properties. Method: Quality control tests of Allium ampeloperasum L, Commiphora mukul (Hook. ex Stocks Engl., Phyllanthus emblica L., Terminalia chebula Retz. and Terminalia bellerica Retz. were performed. Afterwards, different formulations were prepared and their physical properties were evaluated. Subsequently, the formulation was coated and its physicochemical characteristics were assessed. Result: All of the herbs demonstrated good results in quality control tests according to United State Pharmacopeia (USP. Formulation-1 that was completely prepared based on explained manufacturing process of IM in traditional medicine manuscripts did not show suitable pharmaceutical properties. Among different formulations, Formulation-3 that consisted of A. ampeloperasum, C. mukul, P. emblica, T. chebula and T. bellerica, displayed best outcomes through different tests. Conclusion: Modern pharmaceutical approaches can excellently be adapted for IM preparations.
Directory of Open Access Journals (Sweden)
Jarmo Nurmi
2017-05-01
Full Text Available This paper addresses the energy-inefficiency problem of four-degrees-of-freedom (4-DOF hydraulic manipulators through redundancy resolution in robotic closed-loop controlled applications. Because conventional methods typically are local and have poor performance for resolving redundancy with respect to minimum hydraulic energy consumption, global energy-optimal redundancy resolution is proposed at the valve-controlled actuator and hydraulic power system interaction level. The energy consumption of the widely popular valve-controlled load-sensing (LS and constant-pressure (CP systems is effectively minimised through cost functions formulated in a discrete-time dynamic programming (DP approach with minimum state representation. A prescribed end-effector path and important actuator constraints at the position, velocity and acceleration levels are also satisfied in the solution. Extensive field experiments performed on a forestry hydraulic manipulator demonstrate the performance of the proposed solution. Approximately 15–30% greater hydraulic energy consumption was observed with the conventional methods in the LS and CP systems. These results encourage energy-optimal redundancy resolution in future robotic applications of hydraulic manipulators.
Lagrangian formulation of the general relativistic Poynting-Robertson effect
De Falco, Vittorio; Battista, Emmanuele; Falanga, Maurizio
2018-04-01
We propose the Lagrangian formulation for describing the motion of a test particle in a general relativistic, stationary, and axially symmetric spacetime. The test particle is also affected by a radiation field, modeled as a coherent flux of photons traveling along the null geodesics of the background spacetime, including the general relativistic Poynting-Robertson effect. The innovative part of this work is to prove the existence of the potential linked to the dissipative action caused by the Poynting-Robertson effect in general relativity through the help of an integrating factor, depending on the energy of the system. Generally, such kinds of inverse problems involving dissipative effects might not admit a Lagrangian formulation; especially, in general relativity, there are no examples of such attempts in the literature so far. We reduce this general relativistic Lagrangian formulation to the classic case in the weak-field limit. This approach facilitates further studies in improving the treatment of the radiation field, and it contains, for example, some implications for a deeper comprehension of the gravitational waves.
International Nuclear Information System (INIS)
Kulak, R.F.; Kennedy, J.M.; Belytschko, T.B.; Schoeberle, D.F.
1977-01-01
This paper describes finite-element formulations for the thermal stress analysis of LMFBR structures. The first formulation is applicable to large displacement rotation problems in which the strains are small. For this formulation, a general temperature-dependent constituent relationship is derived from a Gibbs potential and a temperature dependent surface. A second formulation is presented for problems characterized by both large displacement-rotations and large strains. Here a set of large strain hypoelastic-plastic relationships are developed to linearly relate the rate of stress to the rate of deformation. These developments were incorporated into two ANL developed finite-element computer codes: the implicit version of STRAW and the 3D Implicit Structural Analaysis code. A set of problems is presented to validate both the 3D and 2D programs and to illustrate their applicability to a variety of problems. (Auth.)
MO-AB-BRA-01: A Global Level Set Based Formulation for Volumetric Modulated Arc Therapy
Energy Technology Data Exchange (ETDEWEB)
Nguyen, D; Lyu, Q; Ruan, D; O’Connor, D; Low, D; Sheng, K [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA (United States)
2016-06-15
Purpose: The current clinical Volumetric Modulated Arc Therapy (VMAT) optimization is formulated as a non-convex problem and various greedy heuristics have been employed for an empirical solution, jeopardizing plan consistency and quality. We introduce a novel global direct aperture optimization method for VMAT to overcome these limitations. Methods: The global VMAT (gVMAT) planning was formulated as an optimization problem with an L2-norm fidelity term and an anisotropic total variation term. A level set function was used to describe the aperture shapes and adjacent aperture shapes were penalized to control MLC motion range. An alternating optimization strategy was implemented to solve the fluence intensity and aperture shapes simultaneously. Single arc gVMAT plans, utilizing 180 beams with 2° angular resolution, were generated for a glioblastoma multiforme (GBM), lung (LNG), and 2 head and neck cases—one with 3 PTVs (H&N3PTV) and one with 4 PTVs (H&N4PTV). The plans were compared against the clinical VMAT (cVMAT) plans utilizing two overlapping coplanar arcs. Results: The optimization of the gVMAT plans had converged within 600 iterations. gVMAT reduced the average max and mean OAR dose by 6.59% and 7.45% of the prescription dose. Reductions in max dose and mean dose were as high as 14.5 Gy in the LNG case and 15.3 Gy in the H&N3PTV case. PTV coverages (D95, D98, D99) were within 0.25% of the prescription dose. By globally considering all beams, the gVMAT optimizer allowed some beams to deliver higher intensities, yielding a dose distribution that resembles a static beam IMRT plan with beam orientation optimization. Conclusions: The novel VMAT approach allows for the search of an optimal plan in the global solution space and generates deliverable apertures directly. The single arc VMAT approach fully utilizes the digital linacs’ capability in dose rate and gantry rotation speed modulation. Varian Medical Systems, NIH grant R01CA188300, NIH grant R43CA183390.
Decision-Tree Formulation With Order-1 Lateral Execution
James, Mark
2007-01-01
A compact symbolic formulation enables mapping of an arbitrarily complex decision tree of a certain type into a highly computationally efficient multidimensional software object. The type of decision trees to which this formulation applies is that known in the art as the Boolean class of balanced decision trees. Parallel lateral slices of an object created by means of this formulation can be executed in constant time considerably less time than would otherwise be required. Decision trees of various forms are incorporated into almost all large software systems. A decision tree is a way of hierarchically solving a problem, proceeding through a set of true/false responses to a conclusion. By definition, a decision tree has a tree-like structure, wherein each internal node denotes a test on an attribute, each branch from an internal node represents an outcome of a test, and leaf nodes represent classes or class distributions that, in turn represent possible conclusions. The drawback of decision trees is that execution of them can be computationally expensive (and, hence, time-consuming) because each non-leaf node must be examined to determine whether to progress deeper into a tree structure or to examine an alternative. The present formulation was conceived as an efficient means of representing a decision tree and executing it in as little time as possible. The formulation involves the use of a set of symbolic algorithms to transform a decision tree into a multi-dimensional object, the rank of which equals the number of lateral non-leaf nodes. The tree can then be executed in constant time by means of an order-one table lookup. The sequence of operations performed by the algorithms is summarized as follows: 1. Determination of whether the tree under consideration can be encoded by means of this formulation. 2. Extraction of decision variables. 3. Symbolic optimization of the decision tree to minimize its form. 4. Expansion and transformation of all nested conjunctive
A Mathematical Optimization Problem in Bioinformatics
Heyer, Laurie J.
2008-01-01
This article describes the sequence alignment problem in bioinformatics. Through examples, we formulate sequence alignment as an optimization problem and show how to compute the optimal alignment with dynamic programming. The examples and sample exercises have been used by the author in a specialized course in bioinformatics, but could be adapted…
A numerical approach to Stefan problem
International Nuclear Information System (INIS)
Kotalik, P.
1993-07-01
The one-dimensional Stefan problem for a thin plate heated by laser pulses is solved by approximating the enthalpy formulation of the problem by C 0 piecewise linear finite elements in space combined with a semi-implicit scheme in time. (author) 6 figs., 5 refs
Directory of Open Access Journals (Sweden)
Yanet Edith Batista Freyre
2013-04-01
Full Text Available It was presented the need of improving the area of Natural Sciences in the teaching-learning process in primary schools to solve problems, as a component in the comprehensive formation of scholars; that is, to get advantage from the curriculum, the cultural-historical experience and the social interaction of the scholar to favor it, is the essence of this article. In this aspect it plays an essential role the knowledge of the contents of the subjects of the area of Natural Sciences in the primary school. They possess wide potentialities to contribute to this pretense, keeping in mind that besides instructing the children in the appropriate interpretation of the phenomena and processes that happen in nature and society, they favor a general culture on the repercussion and the man's sustainable action on nature, as well as the necessity of their care and conservation. RESUMEN: Se abordó la necesidad de perfeccionar el aprendizaje del área de las Ciencias Naturales en el proceso de enseñanza-aprendizaje de la escuela primaria para resolver problemas, como parte de la formación integral del escolar; en tal sentido, aprovechar el currículo, la experiencia histórico – cultural del escolar y su interacción social para favorecerlo, es la esencia de este articulo. En este aspecto juega un papel esencial el tratamiento a los contenidos del área, los que poseen amplias potencialidades para el desarrollo de la resolución de problemas, y de esta forma contribuir a esta pretensión, teniendo en cuenta que además de instruir a los escolares en la adecuada interpretación de los fenómenos y procesos que ocurren en la naturaleza y la sociedad, propicia una cultura general sobre la repercusión y la acción sostenible del hombre sobre la naturaleza, así como la necesidad de su cuidado y conservación.
Institute of Scientific and Technical Information of China (English)
冯大鸣
2011-01-01
本尼斯的一句名言表明了一种重领导而轻管理的倾向，在“管理”还十分粗放的中国，同样出现了“领导”过剩与“管理”短缺的局面。“领导”与“管理”的失衡与断裂，使“领导”沦落为虚饰和取巧的工具，成为旧酒新瓶的华丽标贴，成了优势学校独家把玩的奢侈品。修复“领导”与“管理”的断裂成为我国学校管理实践的当务之急。借鉴国外相关经验，着力于平衡的考核评价、着力于管理技术含量的提高、着力于基本管理难题的破解、着力于骨干教师管理能力培育可以作为修复断裂的基本对策。%A famous saying of Bennis reveals a tendency that pays too much attention to ＂leadership＂ while overlooks ＂management＂. In the still extensive ＂management＂ of China, there exists the situation of excess ＂leadership＂ and shortage of ＂management＂. The imbalance and fracture of ＂leadership＂ and ＂management＂ makes ＂leadership＂ becoming the tool of veneer and cheating, a beautiful label of old wine in new bottle, and a luxury for only elite schools. To restore the fracture of ＂leadership＂ and ＂management＂ is the urgent task for China＇s school management practice. Based on the relevant international experience, the balanced evaluation on ＂leadership＂ and ＂management＂, the improvement of management skills, solving the essential problems in management, and building key teachers＂ capacity in management should be the basic leverage points to restore the linkage between ＂leadership＂ and ＂management＂.
Automated conflict resolution issues
Wike, Jeffrey S.
1991-01-01
A discussion is presented of how conflicts for Space Network resources should be resolved in the ATDRSS era. The following topics are presented: a description of how resource conflicts are currently resolved; a description of issues associated with automated conflict resolution; present conflict resolution strategies; and topics for further discussion.
Formulation studies for mirtazapine orally disintegrating tablets.
Yıldız, Simay; Aytekin, Eren; Yavuz, Burçin; Bozdağ Pehlivan, Sibel; Ünlü, Nurşen
2016-01-01
Orally disintegrating tablets (ODTs) recently have gained much attention to fulfill the needs for pediatric, geriatric, and psychiatric patients with dysphagia. Aim of this study was to develop new ODT formulations containing mirtazapine, an antidepressant drug molecule having bitter taste, by using simple and inexpensive preparation methods such as coacervation, direct compression and to compare their characteristics with those of reference product (Remereon SolTab). Coacervation method was chosen for taste masking of mirtazapine. In vitro characterization studies such as diameter and thickness, weight variation, tablet hardness, tablet friability and disintegration time were performed on tablet formulations. Wetting time and in vitro dissolution tests of developed ODTs also studied using 900 mL 0.1 N HCl medium, 900 mL pH 6.8 phosphate buffer or 900 mL pH 4.5 acetate buffer at 37 ± 0.2 °C as dissolution medium. Ratio of Eudragit® E-100 was chosen as 6% (w/w) since the dissolution profile of A1 (6% Eudragit® E-100) was found closer to the reference product than A2 (4% Eudragit® E-100) and A3 (8% Eudragit® E-100). Group D, E and F formulations were presented better results in terms of disintegration time. Dissolution results indicated that Group E and F formulations showed optimum properties in all three dissolution media. Formulations D1, D4, D5, E3, E4, F1 and F5 found suitable as ODT formulations due to their favorable disintegration times and dissolution profiles. Developed mirtazapine ODTs were found promising in terms of showing the similar characteristics to the original formulation.
TURVA-2012: Formulation of radionuclide release scenarios
International Nuclear Information System (INIS)
Marcos, Nuria; Hjerpe, Thomas; Snellman, Margit; Ikonen, Ari; Smith, Paul
2014-01-01
TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This paper gives a summary of the scenarios and the methodology followed in formulating them as described in TURVA-2012: Formulation of Radionuclide Release Scenarios (Posiva, 2013). The scenarios are further analysed in TURVA-2012: Assessment of Radionuclide Release Scenarios for the Repository System and TURVA-2012: Biosphere Assessment (Posiva, 2012a, 2012b). The formulation of scenarios takes into account the safety functions of the main barriers of the repository system and the uncertainties in the features, events, and processes (FEP) that may affect the entire disposal system (i.e. repository system plus the surface environment) from the emplacement of the first canister until the far future. In the report TURVA-2012: Performance Assessment (2012d), the performance of the engineered and natural barriers has been assessed against the loads expected during the evolution of the repository system and the site. Uncertainties have been identified and these are taken into account in the formulation of radionuclide release scenarios. The uncertainties in the FEP and evolution of the surface environment are taken into account in formulating the surface environment scenarios used ultimately in estimating radiation exposure. Formulating radionuclide release scenarios for the repository system links the reports Performance Assessment and Assessment of Radionuclide Release Scenarios for the Repository System. The formulation of radionuclide release scenarios for the surface environment brings together biosphere description and the surface environment FEP and is the link to the assessment of the surface environment scenarios summarised in TURVA-2012: Biosphere Assessment. (authors)
Petereit, H U; Weisbrod, W
1999-01-01
General considerations concerning the stability of coated dosage forms are discussed, in order to avoid predictable interactions which may cause long-term stability problems. As polymers themselves maintain a high chemical stability and a low reactivity, instability phenomena mainly have to be explained by interactions of low molecular weight substances or physical changes. Possible interactions of functional groups can be predicted easily and insulating subcoates are proper countermeasures. Impurities, remaining in the polymeric material from the manufacturing process, may accelerate the hydrolysis of sensitive drugs. Instabilities of coated dosage forms are mainly based on physical interactions, caused by improper formulations of coating suspensions (i.e. plasticizers or pigments) or the film coating process. Residual moisture or solvents, probably enclosed in the core and migrating over time, may increase the permeability of coatings, due to plasticizing effects. The functionality of coatings from aqueous dispersions is linked to coalescence of latex particles. Thus any incomplete film formation, caused by too high or too low coating temperatures, may result in high permeable coatings. During storage, preferably under stress conditions this process will continue and thus change the release profile. Therefore bed temperatures of 10-20 degrees C above MFT must ensure the formation of homogeneous polymer layers during the coating process. Stability test procedures and packaging materials also need to be adapted to the physicochemical properties of the dosage form, in order to get meaningful results in stability tests.
The geometry of the SLsub(2,c) gauge formulation of general relativity
International Nuclear Information System (INIS)
Kaye, M.
1978-01-01
The formulation of Einstein's general theory of relativity as an SLsub(2,c) gauge theory is considered. Use is made of the language of fibre bundles and general arguments are put forward in favour of the SLsub(2,c) approach to problems connected with the study of the space-time structure. The possibility of deriving the dynamics of the theory from a Yang-Mills-type Lagrangian density is discussed. Finally, the spinor approach is compared with other approaches to the problem of formulating Einstein's theory as a gauge theory
Arora, Shitij; Fourment, Lionel
2018-05-01
In the context of the simulation of industrial hot forming processes, the resultant time-dependent thermo-mechanical multi-field problem (v →,p ,σ ,ɛ ) can be sped up by 10-50 times using the steady-state methods while compared to the conventional incremental methods. Though the steady-state techniques have been used in the past, but only on simple configurations and with structured meshes, and the modern-days problems are in the framework of complex configurations, unstructured meshes and parallel computing. These methods remove time dependency from the equations, but introduce an additional unknown into the problem: the steady-state shape. This steady-state shape x → can be computed as a geometric correction t → on the domain X → by solving the weak form of the steady-state equation v →.n →(t →)=0 using a Streamline Upwind Petrov Galerkin (SUPG) formulation. There exists a strong coupling between the domain shape and the material flow, hence, a two-step fixed point iterative resolution algorithm was proposed that involves (1) the computation of flow field from the resolution of thermo-mechanical equations on a prescribed domain shape and (2) the computation of steady-state shape for an assumed velocity field. The contact equations are introduced in the penalty form both during the flow computation as well as during the free-surface correction. The fact that the contact description is inhomogeneous, i.e., it is defined in the nodal form in the former, and in the weighted residual form in the latter, is assumed to be critical to the convergence of certain problems. Thus, the notion of nodal collocation is invoked in the weak form of the surface correction equation to homogenize the contact coupling. The surface correction algorithm is tested on certain analytical test cases and the contact coupling is tested with some hot rolling problems.
Directory of Open Access Journals (Sweden)
Šoltýsová I.
2016-12-01
Full Text Available Active ingredients in pharmaceuticals differ by their physico-chemical properties and their bioavailability therefore varies. The most frequently used and most convenient way of administration of medicines is oral, however many drugs are little soluble in water. Thus they are not sufficiently effective and suitable for such administration. For this reason a system of lipid based formulations (LBF was developed. Series of formulations were prepared and tested in water and biorelevant media. On the basis of selection criteria, there were selected formulations with the best emulsification potential, good dispersion in the environment and physical stability. Samples of structurally different drugs included in the Class II of the Biopharmaceutics classification system (BCS were obtained, namely Griseofulvin, Glibenclamide, Carbamazepine, Haloperidol, Itraconazol, Triclosan, Praziquantel and Rifaximin, for testing of maximal saturation in formulations prepared from commercially available excipients. Methods were developed for preparation of formulations, observation of emulsification and its description, determination of maximum solubility of drug samples in the respective formulation and subsequent analysis. Saturation of formulations with drugs showed that formulations 80 % XA and 20 % Xh, 35 % XF and 65 % Xh were best able to dissolve the drugs which supports the hypothesis that it is desirable to identify limited series of formulations which could be generally applied for this purpose.
International Nuclear Information System (INIS)
Belsher, J.D.; Meinert, F.L.
2009-01-01
This document presents the differences between two HLW glass formulation models (GFM): The 1996 GFM and 2009 GFM. A glass formulation model is a collection of glass property correlations and associated limits, as well as model validity and solubility constraints; it uses the pretreated HLW feed composition to predict the amount and composition of glass forming additives necessary to produce acceptable HLW glass. The 2009 GFM presented in this report was constructed as a nonlinear optimization calculation based on updated glass property data and solubility limits described in PNNL-18501 (2009). Key mission drivers such as the total mass of HLW glass and waste oxide loading are compared between the two glass formulation models. In addition, a sensitivity study was performed within the 2009 GFM to determine the effect of relaxing various constraints on the predicted mass of the HLW glass.
Formulation of Sustained-Release Diltiazem Matrix Tablets Using ...
African Journals Online (AJOL)
Erah
surface, their drug release behavior appears simple, but ... matrix material for the formulation of ..... formulation F5 (,) and reference formulations. ( , □). 0. 50. 100. 150. 200. 250. 300. 0. 3. 6 .... Coviello T, Matricardi P, Marianecci C, Alhaique F.
Numerical simulation using vorticity-vector potential formulation
Tokunaga, Hiroshi
1993-01-01
An accurate and efficient computational method is needed for three-dimensional incompressible viscous flows in engineering applications. On solving the turbulent shear flows directly or using the subgrid scale model, it is indispensable to resolve the small scale fluid motions as well as the large scale motions. From this point of view, the pseudo-spectral method is used so far as the computational method. However, the finite difference or the finite element methods are widely applied for computing the flow with practical importance since these methods are easily applied to the flows with complex geometric configurations. However, there exist several problems in applying the finite difference method to direct and large eddy simulations. Accuracy is one of most important problems. This point was already addressed by the present author on the direct simulations on the instability of the plane Poiseuille flow and also on the transition to turbulence. In order to obtain high efficiency, the multi-grid Poisson solver is combined with the higher-order, accurate finite difference method. The formulation method is also one of the most important problems in applying the finite difference method to the incompressible turbulent flows. The three-dimensional Navier-Stokes equations have been solved so far in the primitive variables formulation. One of the major difficulties of this method is the rigorous satisfaction of the equation of continuity. In general, the staggered grid is used for the satisfaction of the solenoidal condition for the velocity field at the wall boundary. However, the velocity field satisfies the equation of continuity automatically in the vorticity-vector potential formulation. From this point of view, the vorticity-vector potential method was extended to the generalized coordinate system. In the present article, we adopt the vorticity-vector potential formulation, the generalized coordinate system, and the 4th-order accurate difference method as the
Resolution analyses for selecting an appropriate airborne electromagnetic (AEM) system
DEFF Research Database (Denmark)
Christensen, N.B.; Lawrie, Ken
2012-01-01
is necessary and has to be approached in a pragmatic way involving a range of different aspects. In this paper, we concentrate on the resolution analysis perspective and demonstrate that the inversion analysis must be preferred over the derivative analysis because it takes parameter coupling into account, and...... resolution for a series of models relevant to the survey area by comparing the sum over the data of squares of noise-normalised derivatives. We compare this analysis method with a resolution analysis based on the posterior covariance matrix of an inversion formulation. Both of the above analyses depend......, furthermore, that the derivative analysis generally overestimates the resolution capability. Finally we show that impulse response data are to be preferred over step response data for near-surface resolution....
STRATEGY FORMULATION FOR DEVELOPING BATIK TULIS
Directory of Open Access Journals (Sweden)
Indah Eko Suryani
2015-01-01
Full Text Available The objective of this study was to formulate a development strategy in order to maintain the existence of Batik Tulis Rolla Junior. The study used a case study approach with Rumah Batik Tulis Rolla Junior as the research object. The data were analyzed by a value chain approach to determine the internal and external conditions influencing the existence of the Batik Tulis Rolla Junior. Furthermore, this study also used the analysis of Internal Factor Evaluation (IFE, External Factor Evaluation (EFE, Internal-External (IE Matrix, SWOT, dan Quantitative Strategic Planning Matrix (QSPM to create the development strategy. The results show that the strategies that can be recommended to Rolla Junior include 1 increasing the capital by Kredit Usaha Rakyat (KUR program, 2 conductiong expansions to other regencies, 3 creating a website/blog to promote and perform business transactions, 4 increasing the frequency in joining exhibitions or EXPO both in regional and national levels, 5 conducting researches to solve the problem of coloring which requires sun rays, 6 conducting cooperations with raw material suppliers (backward integration, and 7 finding alternative suppliers of raw materials especially from the areas closer to Jember district.Keywords: development strategy, batik tulis Rolla Junior, SWOT, QSPMABSTRAKPenelitian ini bertujuan merumuskan strategi pengembangan sehingga dapat menjaga eksistensi Batik Tulis Rolla Junior. Penelitian menggunakan pendekatan studi kasus dengan Rolla Junior sebagai objek penelitiannya. Data dianalisis dengan pendekatan rantai nilai untuk mengetahui kondisi internal dan eksternal yang berpengaruh terhadap Batik Tulis kemudian menggunakan analisis Internal Factor Evaluation (IFE, External Factor Evaluation (EFE, Internal-External (IE Matrix, SWOT, dan Quantitative Strategic Planning Matrix (QSPM untuk menyusun strategi pengembangan Batik Tulis Rolla Junior. Hasil penelitian menunjukkan bahwa strategi-straegi prioritas
DEFF Research Database (Denmark)
Christensen, Anders Bøggild; Rasmussen, Tove; Bundesen, Peter Verner
Sociale problemer kan betragtes som selve udgangspunktet for socialt arbejde, hvor ambitionen er at råde bod på problemerne og sikre, at udsatte borgere får en bedre tilværelse. Det betyder også, at diskussionen af sociale problemer er afgørende for den sociale grundfaglighed. I denne bog sætter en...... række fagfolk på tværs af det danske socialfaglige felt fokus på sociale problemer. Det diskuteres, hvad vi overhovedet forstår ved sociale problemer, hvordan de opstår, hvilke konsekvenser de har, og ikke mindst hvordan man som fagprofessionel håndterer sociale problemer i det daglige arbejde. Bogen er...... skrevet som lærebog til professionsuddannelser, hvor sociale problemer udgør en dimension, bl.a. socialrådgiver-, pædagog- og sygeplejerskeuddannelserne....
Initial value formulation of dynamical Chern-Simons gravity
Delsate, Térence; Hilditch, David; Witek, Helvi
2015-01-01
We derive an initial value formulation for dynamical Chern-Simons gravity, a modification of general relativity involving parity-violating higher derivative terms. We investigate the structure of the resulting system of partial differential equations thinking about linearization around arbitrary backgrounds. This type of consideration is necessary if we are to establish well-posedness of the Cauchy problem. Treating the field equations as an effective field theory we find that weak necessary conditions for hyperbolicity are satisfied. For the full field equations we find that there are states from which subsequent evolution is not determined. Generically the evolution system closes, but is not hyperbolic in any sense that requires a first order pseudodifferential reduction. In a cursory mode analysis we find that the equations of motion contain terms that may cause ill-posedness of the initial value problem.
Formulation, in vitro and in vivo evaluation of transdermal patches containing risperidone.
Aggarwal, Geeta; Dhawan, Sanju; Hari Kumar, S L
2013-01-01
The efficacy of oral risperidone treatment in prevention of schizophrenia is well known. However, oral side effects and patient compliance is always a problem for schizophrenics. In this study, risperidone was formulated into matrix transdermal patches to overcome these problems. The formulation factors for such patches, including eudragit RL 100 and eudragit RS 100 as matrix forming polymers, olive oil, groundnut oil and jojoba oil in different concentrations as enhancers and amount of drug loaded were investigated. The transdermal patches containing risperidone were prepared by solvent casting method and characterized for physicochemical and in vitro permeation studies through excised rat skin. Among the tested preparations, formulations with 20% risperidone, 3:2 ERL 100 and ERS 100 as polymers, mixture of olive oil and jojoba oil as enhancer, exhibited greatest cumulative amount of drug permeated (1.87 ± 0.09 mg/cm(2)) in 72 h, so batch ROJ was concluded as optimized formulation and assessed for pharmacokinetic, pharmacodynamic and skin irritation potential. The pharmacokinetic characteristics of the optimized risperidone patch were determined using rabbits, while orally administered risperidone in solution was used for comparison. The calculated relative bioavailability of risperidone transdermal patch was 115.20% with prolonged release of drug. Neuroleptic efficacy of transdermal formulation was assessed by rota-rod and grip test in comparison with control and marketed oral formulations with no skin irritation. This suggests the transdermal application of risperidone holds promise for improved bioavailability and better management of schizophrenia in long-term basis.
Iterative Reconstruction Methods for Hybrid Inverse Problems in Impedance Tomography
DEFF Research Database (Denmark)
Hoffmann, Kristoffer; Knudsen, Kim
2014-01-01
For a general formulation of hybrid inverse problems in impedance tomography the Picard and Newton iterative schemes are adapted and four iterative reconstruction algorithms are developed. The general problem formulation includes several existing hybrid imaging modalities such as current density...... impedance imaging, magnetic resonance electrical impedance tomography, and ultrasound modulated electrical impedance tomography, and the unified approach to the reconstruction problem encompasses several algorithms suggested in the literature. The four proposed algorithms are implemented numerically in two...
A finite element method for flow problems in blast loading
International Nuclear Information System (INIS)
Forestier, A.; Lepareux, M.
1984-06-01
This paper presents a numerical method which describes fast dynamic problems in flow transient situations as in nuclear plants. A finite element formulation has been chosen; it is described by a preprocessor in CASTEM system: GIBI code. For these typical flow problems, an A.L.E. formulation for physical equations is used. So, some applications are presented: the well known problem of shock tube, the same one in 2D case and a last application to hydrogen detonation
Formulation of lubricating grease using Beeswax thickener
Suhaila, N.; Japar, A.; Aizudin, M.; Aziz, A.; Najib Razali, Mohd
2018-04-01
The issues on environmental pollution has brought the industries to seek the alternative green solutions for lubricating grease formulation. The significant challenges in producing modified grease are in which considering the chosen thickener as one of the environmental friendly material. The main purposes of the current research were to formulate lubricant grease using different types of base oils and to study the effect of thickener on the formulated lubricant grease. Used oil and motor oil were used as the base oils for the grease preparation. Beeswax and Damar were used as thickener and additive. The grease is tested based on its consistency, stability and oil bleeding. The prepared greases achieved grease consistency of grade 2 and 3 except for grease with unfiltered used oil. Grease formulated with used oil and synthetic oil tend to harden and loss its lubricating ability under high temperature compared to motor oil’ grease. Grease modification using environmental friendly thickener were successfully formulated but it is considered as a low temperature grease as the beeswax have low melting point of 62°C-65°C.
Bioequivalence assessment of two formulations of ibuprofen
Al-Talla, Zeyad
2011-10-19
Background: This study assessed the relative bioavailability of two formulations of ibuprofen. The first formulation was Doloraz , produced by Al-Razi Pharmaceutical Company, Amman, Jordan. The second forumulation was Brufen , manufactured by Boots Company, Nottingham, UK. Methods and results: A prestudy validation of ibuprofen demonstrated long-term stability, freeze-thaw stability, precision, and accuracy. Twenty-four healthy volunteers were enrolled in this study. After overnight fasting, the two formulations (test and reference) of ibuprofen (100 mg ibuprofen/5 mL suspension) were administered as a single dose on two treatment days separated by a one-week washout period. After dosing, serial blood samples were drawn for a period of 14 hours. Serum harvested from the blood samples was analyzed for the presence of ibuprofen by high-pressure liquid chromatography with ultraviolet detection. Pharmacokinetic parameters were determined from serum concentrations for both formulations. The 90% confidence intervals of the ln-transformed test/reference treatment ratios for peak plasma concentration and area under the concentration-time curve (AUC) parameters were found to be within the predetermined acceptable interval of 80%-125% set by the US Food and Drug Administration. Conclusion: Analysis of variance for peak plasma concentrations and AUC parameters showed no significant difference between the two formulations and, therefore, Doloraz was considered bioequivalent to Brufen. 2011 Al-Talla et al, publisher and licensee Dove Medical Press Ltd.
Mathematical Model and Algorithm for the Reefer Mechanic Scheduling Problem at Seaports
Directory of Open Access Journals (Sweden)
Jiantong Zhang
2017-01-01
Full Text Available With the development of seaborne logistics, the international trade of goods transported in refrigerated containers is growing fast. Refrigerated containers, also known as reefers, are used in transportation of temperature sensitive cargo, such as perishable fruits. This trend brings new challenges to terminal managers, that is, how to efficiently arrange mechanics to plug and unplug power for the reefers (i.e., tasks at yards. This work investigates the reefer mechanics scheduling problem at container ports. To minimize the sum of the total tardiness of all tasks and the total working distance of all mechanics, we formulate a mathematical model. For the resolution of this problem, we propose a DE algorithm which is combined with efficient heuristics, local search strategies, and parameter adaption scheme. The proposed algorithm is tested and validated through numerical experiments. Computational results demonstrate the effectiveness and efficiency of the proposed algorithm.
Isogeometric shell formulation based on a classical shell model
Niemi, Antti
2012-09-04
This paper constitutes the first steps in our work concerning isogeometric shell analysis. An isogeometric shell model of the Reissner-Mindlin type is introduced and a study of its accuracy in the classical pinched cylinder benchmark problem presented. In contrast to earlier works [1,2,3,4], the formulation is based on a shell model where the displacement, strain and stress fields are defined in terms of a curvilinear coordinate system arising from the NURBS description of the shell middle surface. The isogeometric shell formulation is implemented using the PetIGA and igakit software packages developed by the authors. The igakit package is a Python package used to generate NURBS representations of geometries that can be utilised by the PetIGA finite element framework. The latter utilises data structures and routines of the portable, extensible toolkit for scientific computation (PETSc), [5,6]. The current shell implementation is valid for static, linear problems only, but the software package is well suited for future extensions to geometrically and materially nonlinear regime as well as to dynamic problems. The accuracy of the approach in the pinched cylinder benchmark problem and present comparisons against the h-version of the finite element method with bilinear elements. Quadratic, cubic and quartic NURBS discretizations are compared against the isoparametric bilinear discretization introduced in [7]. The results show that the quadratic and cubic NURBS approximations exhibit notably slower convergence under uniform mesh refinement as the thickness decreases but the quartic approximation converges relatively quickly within the standard variational framework. The authors future work is concerned with building an isogeometric finite element method for modelling nonlinear structural response of thin-walled shells undergoing large rigid-body motions. The aim is to use the model in a aeroelastic framework for the simulation of flapping wings.
International Nuclear Information System (INIS)
Ricaud, J.M.; Masson, R.; Masson, R.
2009-01-01
The Laplace-Carson transform classically used for homogenization of linear viscoelastic heterogeneous media yields integral formulations of effective behaviours. These are far less convenient than internal variables formulations with respect to computational aspects as well as to theoretical extensions to closely related problems such as ageing viscoelasticity. Noticing that the collocation method is usually adopted to invert the Laplace-Carson transforms, we first remark that this approximation is equivalent to an internal variables formulation which is exact in some specific situations. This result is illustrated for a two-phase composite with phases obeying a compressible Maxwellian behaviour. Next, an incremental formulation allows to extend at each time step the previous general framework to ageing viscoelasticity. Finally, with the help of a creep test of a porous viscoelastic matrix reinforced with elastic inclusions, it is shown that the method yields accurate predictions (comparing to reference results provided by periodic cell finite element computations). (authors)
Continuum mechanics and thermodynamics in the Hamilton and the Godunov-type formulations
Peshkov, Ilya; Pavelka, Michal; Romenski, Evgeniy; Grmela, Miroslav
2018-01-01
Continuum mechanics with dislocations, with the Cattaneo-type heat conduction, with mass transfer, and with electromagnetic fields is put into the Hamiltonian form and into the form of the Godunov-type system of the first-order, symmetric hyperbolic partial differential equations (SHTC equations). The compatibility with thermodynamics of the time reversible part of the governing equations is mathematically expressed in the former formulation as degeneracy of the Hamiltonian structure and in the latter formulation as the existence of a companion conservation law. In both formulations the time irreversible part represents gradient dynamics. The Godunov-type formulation brings the mathematical rigor (the local well posedness of the Cauchy initial value problem) and the possibility to discretize while keeping the physical content of the governing equations (the Godunov finite volume discretization).
Cyclodextrins as excipients in tablet formulations.
Conceição, Jaime; Adeoye, Oluwatomide; Cabral-Marques, Helena Maria; Lobo, José Manuel Sousa
2018-04-22
This paper aims to provide a critical review of cyclodextrins as excipients in tablet formulations, highlighting: (i) the principal pharmaceutical applications of cyclodextrins; (ii) the most relevant technological aspects in pharmaceutical formulation development; and (iii) the actual regulatory status of cyclodextrins. Moreover, several illustrative examples are presented. Cyclodextrins can be used as complexing excipients in tablet formulations for low-dose drugs. By contrast, for medium-dose drugs and/or when the complexation efficiency is low, the methods to enhance the complexation efficiency play a key part in reducing the cyclodextrin quantity. In addition, these compounds are used as fillers, disintegrants, binders and multifunctional direct compression excipients of the tablets. Copyright © 2018 Elsevier Ltd. All rights reserved.
STRATEGY FORMULATION PROCESS AND INNOVATION PERFORMANCE NEXUS
Directory of Open Access Journals (Sweden)
Chijioke Nwachukwu
2018-03-01
Full Text Available The purpose of this study is to examine the link between strategy formulation process and innovation performance indicators in microfinance banks in Nigeria (MFBs. 100 employees of leading microfinance banks were randomly selected for this study. 80 questionnaires were returned but only 76 were found usable for the analysis. Regression analysis technique was used in examining the nature of the relationships of the variables and for hypotheses testing. The authors used exploratory factor analysis and Cronbach's alpha to test for the validity and reliability of the questionnaires. The results show that strategy formulation process has a positive effect on process innovation performance, product innovation performance and marketing innovation performance. Thus, all the three hypotheses tested were supported. The authors, therefore, concludes that a systematic strategy formulation process is necessary for firms to achieve and sustain process innovation performance, product innovation performance and marketing innovation performance. This study proposed suggestion for further studies.
Formulating viscous hydrodynamics for large velocity gradients
International Nuclear Information System (INIS)
Pratt, Scott
2008-01-01
Viscous corrections to relativistic hydrodynamics, which are usually formulated for small velocity gradients, have recently been extended from Navier-Stokes formulations to a class of treatments based on Israel-Stewart equations. Israel-Stewart treatments, which treat the spatial components of the stress-energy tensor τ ij as dynamical objects, introduce new parameters, such as the relaxation times describing nonequilibrium behavior of the elements τ ij . By considering linear response theory and entropy constraints, we show how the additional parameters are related to fluctuations of τ ij . Furthermore, the Israel-Stewart parameters are analyzed for their ability to provide stable and physical solutions for sound waves. Finally, it is shown how these parameters, which are naturally described by correlation functions in real time, might be constrained by lattice calculations, which are based on path-integral formulations in imaginary time
DEFF Research Database (Denmark)
N. Gordon, Jeffery; Ringe, Georg
2015-01-01
Bank resolution is a key pillar of the European Banking Union. This column argues that the current structure of large EU banks is not conducive to an effective and unbiased resolution procedure. The authors would require systemically important banks to reorganise into a ‘holding company’ structure......, where the parent company holds unsecured term debt sufficient to cover losses at its operating financial subsidiaries. This would facilitate a ‘single point of entry’ resolution procedure, minimising the risk of creditor runs and destructive ring-fencing by national regulators....
Alternative Dispute Resolution – Justice without Trial?
Directory of Open Access Journals (Sweden)
Angelica Roşu
2012-05-01
Full Text Available This research is proposed to analyze the alternative means of dispute resolution, as an alternativeof justice, or as a justice alternative, after studying both European critical literature and national one. Thephrase „alternative dispute resolution” means any alternative way of dispute resolution method whereby two ormore people try using a third party to reach a solution to the problem that precludes them, whether it ismediation, conciliation, assisted negotiation. In this research, we proposed to use the observation as a commonmethod. We concluded that the main reason of the alternative means for dispute resolution results from thepossibility to avoid the judicial system that makes it available for the litigants. It was also shown that users ofalternative means for dispute resolution not seek to resolve the dispute outside a court as an amicablesettlement, negotiated, consensual of their dispute.
Sibling Conflict Resolution Skills: Assessment and Training
Thomas, Brett W.; Roberts, Mark W.
2009-01-01
Sibling conflict can rise to the level of a clinical problem. In Phase 1 a lengthy behavioral role-play analog sampling child reactions to normal sibling conflicts was successfully shortened. In Phase 2 normal children who lacked sibling conflict resolution skills were randomly assigned to a Training or Measurement Only condition. Training…
Scalable algorithms for contact problems
Dostál, Zdeněk; Sadowská, Marie; Vondrák, Vít
2016-01-01
This book presents a comprehensive and self-contained treatment of the authors’ newly developed scalable algorithms for the solutions of multibody contact problems of linear elasticity. The brand new feature of these algorithms is theoretically supported numerical scalability and parallel scalability demonstrated on problems discretized by billions of degrees of freedom. The theory supports solving multibody frictionless contact problems, contact problems with possibly orthotropic Tresca’s friction, and transient contact problems. It covers BEM discretization, jumping coefficients, floating bodies, mortar non-penetration conditions, etc. The exposition is divided into four parts, the first of which reviews appropriate facets of linear algebra, optimization, and analysis. The most important algorithms and optimality results are presented in the third part of the volume. The presentation is complete, including continuous formulation, discretization, decomposition, optimality results, and numerical experimen...
RAACFDb: Rheumatoid arthritis ayurvedic classical formulations database.
Mohamed Thoufic Ali, A M; Agrawal, Aakash; Sajitha Lulu, S; Mohana Priya, A; Vino, S
2017-02-02
In the past years, the treatment of rheumatoid arthritis (RA) has undergone remarkable changes in all therapeutic modes. The present newfangled care in clinical research is to determine and to pick a new track for better treatment options for RA. Recent ethnopharmacological investigations revealed that traditional herbal remedies are the most preferred modality of complementary and alternative medicine (CAM). However, several ayurvedic modes of treatments and formulations for RA are not much studied and documented from Indian traditional system of medicine. Therefore, this directed us to develop an integrated database, RAACFDb (acronym: Rheumatoid Arthritis Ayurvedic Classical Formulations Database) by consolidating data from the repository of Vedic Samhita - The Ayurveda to retrieve the available formulations information easily. Literature data was gathered using several search engines and from ayurvedic practitioners for loading information in the database. In order to represent the collected information about classical ayurvedic formulations, an integrated database is constructed and implemented on a MySQL and PHP back-end. The database is supported by describing all the ayurvedic classical formulations for the treatment rheumatoid arthritis. It includes composition, usage, plant parts used, active ingredients present in the composition and their structures. The prime objective is to locate ayurvedic formulations proven to be quite successful and highly effective among the patients with reduced side effects. The database (freely available at www.beta.vit.ac.in/raacfdb/index.html) hopefully enables easy access for clinical researchers and students to discover novel leads with reduced side effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.