Science.gov

Sample records for formal description techniques

  1. Automatic derivation of formal software specifications from informal descriptions

    NASA Technical Reports Server (NTRS)

    Miriyala, Kanth; Harandi, Mehdi T.

    1991-01-01

    SPECIFIER, an interactive system which derives formal specifications of data types and programs from their informal descriptions, is described. The process of deriving formal specifications is viewed as a problem-solving process. The system uses common problem-solving techniques such as schemas, analogy, and difference-based reasoning to derive formal specifications. If an informal description is a commonly occurring operation for which the system has a schema, then the formal specification is derived by instantiating the schema. If there is no such schema, SPECIFIER tries to find a previously solved problem which is analogous to the current problem. If the problem found is directly analogous to the current problem, it applies an analogy mapping to obtain a formal specification. On the other hand, if the analogy found is only approximate, it solves the directly analogous part of the problem by analogy and performs difference-based reasoning using the remaining (unmatched) parts to transform the formal specification obtained by analogy to a formal specification for the entire original problem.

  2. A Comparative Assessment of System Description Methodologies and Formal Specification Languages

    DTIC Science & Technology

    1991-03-01

    simulation, two programming languages based on Interval Temporal Logic (ITL), named Tempura [Mos86] and Tokio [F+86], were designed and implemented...A. Vissers, and M. Diaz. The Formal Description Technique LOTOS. North-Holland, 1989. 34 (F+861 M. Fujita et al. Tokio : Logic programming language

  3. Formal description of aggregates of a generalised model of interaction processes in computer networks

    SciTech Connect

    Ratsin, Yu.V.

    1984-01-01

    The realisation using PL/1 of a formal description of a set of interaction process functions in computer networks using the language of discrete parallel processes is described. The formal description is intended for conducting computer modelling experiments. 4 references.

  4. Semi-Formal Description of KVM/370 Trusted Processes

    DTIC Science & Technology

    1977-12-09

    rmnNT A~ /( -Ap.rove.d foT public zlaw 12 22 L v0 Distri ~ubution unlimited / MI 3 December 1377 System Development Corporation Contract MDA903-76-C...Dist Special 11 3+ 9 December 1577 System Development Corporation Operator ProcessTI-9/1/9 Operator Process Semi-Formal Description This section...llapUser Id) Answer: recordJ HMIS: string Text: string emd 2 9 Decemberr 1977 System Development Corporation Operator Process TM-68G2/111/08

  5. Best behaviour? Ontologies and the formal description of animal behaviour.

    PubMed

    Gkoutos, Georgios V; Hoehndorf, Robert; Tsaprouni, Loukia; Schofield, Paul N

    2015-10-01

    The development of ontologies for describing animal behaviour has proved to be one of the most difficult of all scientific knowledge domains. Ranging from neurological processes to human emotions, the range and scope needed for such ontologies is highly challenging, but if data integration and computational tools such as automated reasoning are to be fully applied in this important area the underlying principles of these ontologies need to be better established and development needs detailed coordination. Whilst the state of scientific knowledge is always paramount in ontology and formal description framework design, this is a particular problem with neurobehavioural ontologies where our understanding of the relationship between behaviour and its underlying biophysical basis is currently in its infancy. In this commentary, we discuss some of the fundamental problems in designing and using behaviour ontologies, and present some of the best developed tools in this domain.

  6. Advanced Tools and Techniques for Formal Techniques in Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Knight, John C.

    2005-01-01

    This is the final technical report for grant number NAG-1-02101. The title of this grant was "Advanced Tools and Techniques for Formal Techniques In Aerospace Systems". The principal investigator on this grant was Dr. John C. Knight of the Computer Science Department, University of Virginia, Charlottesville, Virginia 22904-4740. This report summarizes activities under the grant during the period 7/01/2002 to 9/30/2004. This report is organized as follows. In section 2, the technical background of the grant is summarized. Section 3 lists accomplishments and section 4 lists students funded under the grant. In section 5, we present a list of presentations given at various academic and research institutions about the research conducted. Finally, a list of publications generated under this grant is included in section 6.

  7. A relativistic description of MOND using the Palatini formalism in an extended metric theory of gravity

    NASA Astrophysics Data System (ADS)

    Barrientos, E.; Mendoza, S.

    2016-10-01

    We construct a relativistic metric description of MOND using the Palatini formalism following the f(χ) = χb description of T. Bernal et al. (Eur. Phys. J. C 71, 1794 (2011)). We show that in order to recover the non-relativistic MOND regime where, for circular orbits the Tully-Fisher law replaces Kepler's third law, the value of the parameter b = 3/2, which is coincident with the value found using the pure metric formalism of T. Bernal et al. Unlike this pure metric formalism, which yields fourth-order field equations, the Palatini approach yields second-order field equations, which is a desirable requirement from a theoretical perspective. Thus, the phenomenology associated to astrophysical phenomena with Tully-Fisher scalings can be accounted for using this proposal, without the need to introduce any non-baryonic dark matter particles.

  8. Formal Techniques for Synchronized Fault-Tolerant Systems

    NASA Technical Reports Server (NTRS)

    DiVito, Ben L.; Butler, Ricky W.

    1992-01-01

    We present the formal verification of synchronizing aspects of the Reliable Computing Platform (RCP), a fault-tolerant computing system for digital flight control applications. The RCP uses NMR-style redundancy to mask faults and internal majority voting to purge the effects of transient faults. The system design has been formally specified and verified using the EHDM verification system. Our formalization is based on an extended state machine model incorporating snapshots of local processors clocks.

  9. Formal nomenclature and description of cryptic species of the Encyrtus sasakii complex (Hymenoptera: Encyrtidae)

    PubMed Central

    Wang, Ying; Zhou, Qing-Song; Qiao, Hui-Jie; Zhang, Ai-Bing; Yu, Fang; Wang, Xu-Bo; Zhu, Chao-Dong; Zhang, Yan-Zhou

    2016-01-01

    With the recent development of molecular approaches to species delimitation, a growing number of cryptic species have been discovered in what had previously been thought to be single morpho-species. Molecular methods, such as DNA barcoding, have greatly enhanced our knowledge of taxonomy, but taxonomy remains incomplete and needs a formal species nomenclature and description to facilitate its use in other scientific fields. A previous study using DNA barcoding, geometric morphometrics and mating tests revealed at least two cryptic species in the Encyrtus sasakii complex. (Hymenoptera: Encyrtidae). To describe these two new species formally (Encyrtus eulecaniumiae sp. nov. and Encyrtus rhodococcusiae sp. nov.), a detailed morphometric study of Encyrtus spp. was performed in addition to the molecular analysis and evaluation of biological data. Morphometric analyses, a multivariate ratio analysis (MRA) and a geometric morphometric analysis (GMA) revealed a great number of differences between the species, but reliable characteristics were not observed for diagnosing the cryptic species. We thus diagnosed these three Encyrtus species on the basis of the characteristics that resulted from genetic markers (mitochondrial cytochrome c oxidase subunit I and nuclear 28S rRNA) and biological data. A formal nomenclature and description of cryptic species was provided on the basis of an integrated taxonomy. PMID:27698441

  10. Medication dispensing errors in Palestinian community pharmacy practice: a formal consensus using the Delphi technique.

    PubMed

    Shawahna, Ramzi; Haddad, Aseel; Khawaja, Baraa; Raie, Rand; Zaneen, Sireen; Edais, Tasneem

    2016-10-01

    Background Medication dispensing errors (MDEs) are frequent in community pharmacy practice. A definition of MDEs and scenarios representing MDE situations in Palestinian community pharmacy practice were not previously approached using formal consensus techniques. Objective This study was conducted to achieve consensus on a definition of MDEs and a wide range of scenarios that should or should not be considered as MDEs in Palestinian community pharmacy practice by a panel of community pharmacists. Setting Community pharmacy practice in Palestine. Method This was a descriptive study using the Delphi technique. A panel of fifty community pharmacists was recruited from different geographical locations of the West Bank of Palestine. A three round Delphi technique was followed to achieve consensus on a proposed definition of MDEs and 83 different scenarios representing potential MDEs using a nine-point scale. Main outcome measure Agreement or disagreement of a panel of community pharmacists on a proposed definition of MDEs and a series of scenarios representing potential MDEs. Results In the first Delphi round, views of key contact community pharmacists on MDEs were explored and situations representing potential MDEs were collected. In the second Delphi round, consensus was achieved to accept the proposed definition and to include 49 (59 %) of the 83 proposed scenarios as MDEs. In the third Delphi round, consensus was achieved to include further 13 (15.7 %) scenarios as MDEs, exclude 9 (10.8 %) scenarios and the rest of 12 (14.5 %) scenarios were considered equivocal based on the opinions of the panelists. Conclusion Consensus on a definition of MDEs and scenarios representing MDE situations in Palestinian community pharmacy practice was achieved using a formal consensus technique. The use of consensual definitions and scenarios representing MDE situations in community pharmacy practice might minimize methodological variations and their significant effects on the

  11. Experience with Formal Methods techniques at the Jet Propulsion Laboratory from a quality assurance perspective

    NASA Technical Reports Server (NTRS)

    Kelly, John C.; Covington, Rick

    1993-01-01

    Recent experience with Formal Methods (FM) in the Software Quality Assurance Section at the Jet Propulsion Lab is presented. An integrated Formal Method process is presented to show how related existing requirements analysis and FM techniques complement one another. Example application of FM techniques such as formal specifications and specification animators are presented. The authors suggest that the quality assurance organization is a natural home for the Formal Methods specialist, whose expertise can then be used to best advantage across a range of projects.

  12. Corrected thermodynamic description of adsorption via formalism of the theory of volume filling of micropores.

    PubMed

    Terzyk, Artur P; Gauden, Piotr A; Rychlicki, Gerhard

    2006-06-01

    Based on the series of benzene adsorption and related enthalpy of adsorption data measured on porous carbons that possess various porous structures, we show that the creation of a solidlike structure in pores depends on the average pore diameter of an adsorbent. Taking into account the solidlike adsorbed phase in the thermodynamic description of the adsorption process via the formalism of the theory of volume filling of micropores (TVFM) leads to very good agreement between the data measured experimentally and those calculated from TVFM. Finally we show that the boundary between solidlike and liquidlike structures of benzene molecules in carbon pores is located around the average pore diameter, close to ca. 2.1-2.4 nm.

  13. Nursing students' reading and English aptitudes and their relationship to discipline-specific formal writing ability: a descriptive correlational study.

    PubMed

    Newton, Sarah; Moore, Gary

    2010-01-01

    Formal writing assignments are commonly used in nursing education to develop students' critical thinking skills, as well as to enhance their communication abilities. However, writing apprehension is a common phenomenon among nursing students. It has been suggested that reading and English aptitudes are related to formal writing ability, yet neither the reading nor the English aptitudes of undergraduate nursing students have been described in the literature, and the relationships that reading and English aptitude have with formal writing ability have not been explored. The purpose of this descriptive correlational study was to describe writing apprehension and to assess the relationships among reading and English aptitude and discipline-specific formal writing ability among undergraduate nursing students. The study sample consisted of 146 sophomores from one baccalaureate nursing program. The results indicated that both reading and English aptitude were related to students' formal writing ability.

  14. Research in advanced formal theorem-proving techniques

    NASA Technical Reports Server (NTRS)

    Rulifson, J. F.

    1971-01-01

    The present status is summarized of a continuing research program aimed at the design and implementation of a language for expressing problem-solving procedures in several areas of artificial intelligence, including program synthesis, robot planning, and theorem proving. Notations, concepts, and procedures common to the representation and solution of many of these problems were abstracted and incorporated as features into the language. The areas of research covered are described, and abstracts of six papers that contain extensive description and technical detail of the work are presented.

  15. V and V of Lexical, Syntactic and Semantic Properties for Interactive Systems Through Model Checking of Formal Description of Dialog

    NASA Technical Reports Server (NTRS)

    Brat, Guillaume P.; Martinie, Celia; Palanque, Philippe

    2013-01-01

    During early phases of the development of an interactive system, future system properties are identified (through interaction with end users in the brainstorming and prototyping phase of the application, or by other stakehold-ers) imposing requirements on the final system. They can be specific to the application under development or generic to all applications such as usability principles. Instances of specific properties include visibility of the aircraft altitude, speed… in the cockpit and the continuous possibility of disengaging the autopilot in whatever state the aircraft is. Instances of generic properties include availability of undo (for undoable functions) and availability of a progression bar for functions lasting more than four seconds. While behavioral models of interactive systems using formal description techniques provide complete and unambiguous descriptions of states and state changes, it does not provide explicit representation of the absence or presence of properties. Assessing that the system that has been built is the right system remains a challenge usually met through extensive use and acceptance tests. By the explicit representation of properties and the availability of tools to support checking these properties, it becomes possible to provide developers with means for systematic exploration of the behavioral models and assessment of the presence or absence of these properties. This paper proposes the synergistic use two tools for checking both generic and specific properties of interactive applications: Petshop and Java PathFinder. Petshop is dedicated to the description of interactive system behavior. Java PathFinder is dedicated to the runtime verification of Java applications and as an extension dedicated to User Interfaces. This approach is exemplified on a safety critical application in the area of interactive cockpits for large civil aircrafts.

  16. A description of seismic amplitude techniques

    NASA Astrophysics Data System (ADS)

    Shadlow, James

    2014-02-01

    The acquisition of seismic data is a non-invasive technique used for determining the sub surface geology. Changes in lithology and fluid fill affect the seismic wavelet. Analysing seismic data for direct hydrocarbon indicators (DHIs), such as full stack amplitude anomalies, or amplitude variation with offset (AVO), can help a seismic interpreter relate the geophysical response to real geology and, more importantly, to distinguish the presence of hydrocarbons. Inversion is another commonly used technique that attempts to tie the seismic data back to the geology. Much has been written about these techniques, and attempting to gain an understanding on the theory and application of them by reading through various journals can be quite daunting. The purpose of this paper is to briefly outline DHI analysis, including full stack amplitude anomalies, AVO and inversion and show the relationship between all three. The equations presented have been included for completeness, but the reader can pass over the mathematical detail.

  17. New modes of particle accelerations techniques and sources. Formal report

    SciTech Connect

    Parsa, Z.

    1996-12-31

    This Report includes copies of transparencies and notes from the presentations made at the Symposium on New Modes of Particle Accelerations - Techniques and Sources, August 19-23, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report.

  18. Descriptive Statistical Techniques for Librarians. 2nd Edition.

    ERIC Educational Resources Information Center

    Hafner, Arthur W.

    A thorough understanding of the uses and applications of statistical techniques is integral in gaining support for library funding or new initiatives. This resource is designed to help practitioners develop and manipulate descriptive statistical information in evaluating library services, tracking and controlling limited resources, and analyzing…

  19. Limitations of the Dirac formalism as a descriptive framework for cognition.

    PubMed

    Kaznatcheev, Artem; Shultz, Thomas R

    2013-06-01

    We highlight methodological and theoretical limitations of the authors' Dirac formalism and suggest the von Neumann open systems approach as a resolution. The open systems framework is a generalization of classical probability and we hope it will allow cognitive scientists to extend quantum probability from perception, categorization, memory, decision making, and similarity judgments to phenomena in learning and development.

  20. Computing biological functions using BioΨ, a formal description of biological processes based on elementary bricks of actions

    PubMed Central

    Pérès, Sabine; Felicori, Liza; Rialle, Stéphanie; Jobard, Elodie; Molina, Franck

    2010-01-01

    Motivation: In the available databases, biological processes are described from molecular and cellular points of view, but these descriptions are represented with text annotations that make it difficult to handle them for computation. Consequently, there is an obvious need for formal descriptions of biological processes. Results: We present a formalism that uses the BioΨ concepts to model biological processes from molecular details to networks. This computational approach, based on elementary bricks of actions, allows us to calculate on biological functions (e.g. process comparison, mapping structure–function relationships, etc.). We illustrate its application with two examples: the functional comparison of proteases and the functional description of the glycolysis network. This computational approach is compatible with detailed biological knowledge and can be applied to different kinds of systems of simulation. Availability: www.sysdiag.cnrs.fr/publications/supplementary-materials/BioPsi_Manager/ Contact: sabine.peres@sysdiag.cnrs.fr; franck.molina@sysdiag.cnrs.fr Supplementary information: Supplementary data are available at Bioinformatics online. PMID:20448138

  1. A Return to Linnaeus's Focus on Diagnosis, Not Description: The Use of DNA Characters in the Formal Naming of Species.

    PubMed

    Renner, Susanne S

    2016-11-01

    Descriptions and diagnoses are alternative choices in all Codes of Nomenclature because Linnaeus relied on diagnoses, not descriptions, to name ca. 13,400 animals, plants, and fungi. A diagnosis names characters in which a new taxon differs from the most similar known taxon; a description mixes taxonomically informative and uninformative features, usually without indicating which is which. The first formal diagnoses of new taxa that included DNA-based characters came out in 2001, and by November 2015, at least 98 names of species of acoels, lichens, angiosperms, annelids, alveolates, arachnids, centipedes, turtles, fishes, butterflies, mollusks, nematodes, and pathogenic fungi have been published based on diagnostic mitochondrial, plastid, or nuclear DNA substitutions, indels, or rarely genetic distances, with or without additional morphological features. Authors have found diverse ways to specify the diagnostic traits (all published studies are here tabulated). While descriptions try to "cover" within-species variation, a goal rarely accomplished because of (i) the stochastic nature of specimen availability (thousands of species are known from single collections) and (ii) the subjective circumscription of species, the purpose of diagnoses was and is speedy identification. Linnaeus tried to achieve this by citing images, geographic occurrence, and previous literature. The renewed attention to sharp diagnosis now coincides with worldwide barcoding efforts, may speed up formal naming, and matches the increasing reliance on DNA for both classification and identification. I argue for DNA-based diagnoses of new species becoming a recommendation in all Codes, not just the bacterial code. [Codes of Nomenclature; description; diagnosis; DNA-based diagnosis; naming new species; nomenclature.

  2. Unified Description of Electron-Nucleus Scattering within the Spectral Function Formalism.

    PubMed

    Rocco, Noemi; Lovato, Alessandro; Benhar, Omar

    2016-05-13

    The formalism based on factorization and nuclear spectral functions has been generalized to treat transition matrix elements involving two-nucleon currents, whose contribution to the nuclear electromagnetic response in the transverse channel is known to be significant. We report the results of calculations of the inclusive electron-carbon cross section, showing that the inclusion of processes involving two-nucleon currents appreciably improves the agreement between theory and data in the dip region, between the quasielastic and Δ-production peaks. The relation to approaches based on the independent particle of the nucleus and the implications for the analysis of flux-integrated neutrino-nucleus cross sections are discussed.

  3. Innovative techniques for the description of reservoir heterogeneity using tracers

    SciTech Connect

    Pope, G.; Sepehrnoori, K.

    1991-09-01

    The objective of this research is to develop an advanced, innovative technique for the description of reservoir heterogeneity. This proposed method consists of using tracers in single-well backflow tests. The general idea is to make use of fluid drift in the reservoir either due to naturally occurring pressure gradients in the reservoir, or by deliberately imposed pressure gradients using adjacent injection and production wells in the same reservoir. The analytical tool that will be used to design and interpret these tests is a compositional reservoir simulator with special features added and tested specifically for this purpose. 2 refs., 5 figs.

  4. Evaluation of drug-polymer solubility curves through formal statistical analysis: comparison of preparation techniques.

    PubMed

    Knopp, Matthias Manne; Olesen, Niels Erik; Holm, Per; Löbmann, Korbinian; Holm, René; Langguth, Peter; Rades, Thomas

    2015-01-01

    In this study, the influence of the preparation technique (ball milling, spray drying, and film casting) of a supersaturated amorphous dispersion on the quality of solubility determinations of indomethacin in polyvinylpyrrolidone was investigated by means of statistical analysis. After annealing of the amorphous dispersions above the crystallization temperature for 2 h, the solubility curve was derived from the glass transition temperature of the demixed material using the Gordon-Taylor relationship and fitting with the Flory-Huggins model. The study showed that the predicted solubility from the ball-milled mixtures was not consistent with those from spray drying and film casting, indicating fundamental differences between the preparation techniques. Through formal statistical analysis, the best combination of fit to the Flory-Huggins model and reproducibility of the measurements was analyzed. Ball milling provided the best reproducibility of the three preparation techniques; however, an analysis of residuals revealed a systematic error. In contrast, film casting demonstrated a good fit to the model but poor reproducibility of the measurements. Therefore, this study recommends that techniques such as spray drying or potentially film casting (if experimental reproducibility can be improved) should be used to prepare the amorphous dispersions when performing solubility measurements of this kind.

  5. Towards a formal description of the collapse approach to the inflationary origin of the seeds of cosmic structure

    SciTech Connect

    Diez-Tejedor, Alberto; Sudarsky, Daniel E-mail: sudarsky@nucleares.unam.mx

    2012-07-01

    Inflation plays a central role in our current understanding of the universe. According to the standard viewpoint, the homogeneous and isotropic mode of the inflaton field drove an early phase of nearly exponential expansion of the universe, while the quantum fluctuations (uncertainties) of the other modes gave rise to the seeds of cosmic structure. However, if we accept that the accelerated expansion led the universe into an essentially homogeneous and isotropic space-time, with the state of all the matter fields in their vacuum (except for the zero mode of the inflaton field), we can not escape the conclusion that the state of the universe as a whole would remain always homogeneous and isotropic. It was recently proposed in [A. Perez, H. Sahlmann and D. Sudarsky, {sup O}n the quantum origin of the seeds of cosmic structure{sup ,} Class. Quant. Grav. 23 (2006) 2317–2354] that a collapse (representing physics beyond the established paradigm, and presumably associated with a quantum-gravity effect à la Penrose) of the state function of the inflaton field might be the missing element, and thus would be responsible for the emergence of the primordial inhomogeneities. Here we will discuss a formalism that relies strongly on quantum field theory on curved space-times, and within which we can implement a detailed description of such a process. The picture that emerges clarifies many aspects of the problem, and is conceptually quite transparent. Nonetheless, we will find that the results lead us to argue that the resulting picture is not fully compatible with a purely geometric description of space-time.

  6. Formalisms for user interface specification and design

    NASA Technical Reports Server (NTRS)

    Auernheimer, Brent J.

    1989-01-01

    The application of formal methods to the specification and design of human-computer interfaces is described. A broad outline of human-computer interface problems, a description of the field of cognitive engineering and two relevant research results, the appropriateness of formal specification techniques, and potential NASA application areas are described.

  7. Neural systems language: a formal modeling language for the systematic description, unambiguous communication, and automated digital curation of neural connectivity.

    PubMed

    Brown, Ramsay A; Swanson, Larry W

    2013-09-01

    Systematic description and the unambiguous communication of findings and models remain among the unresolved fundamental challenges in systems neuroscience. No common descriptive frameworks exist to describe systematically the connective architecture of the nervous system, even at the grossest level of observation. Furthermore, the accelerating volume of novel data generated on neural connectivity outpaces the rate at which this data is curated into neuroinformatics databases to synthesize digitally systems-level insights from disjointed reports and observations. To help address these challenges, we propose the Neural Systems Language (NSyL). NSyL is a modeling language to be used by investigators to encode and communicate systematically reports of neural connectivity from neuroanatomy and brain imaging. NSyL engenders systematic description and communication of connectivity irrespective of the animal taxon described, experimental or observational technique implemented, or nomenclature referenced. As a language, NSyL is internally consistent, concise, and comprehensible to both humans and computers. NSyL is a promising development for systematizing the representation of neural architecture, effectively managing the increasing volume of data on neural connectivity and streamlining systems neuroscience research. Here we present similar precedent systems, how NSyL extends existing frameworks, and the reasoning behind NSyL's development. We explore NSyL's potential for balancing robustness and consistency in representation by encoding previously reported assertions of connectivity from the literature as examples. Finally, we propose and discuss the implications of a framework for how NSyL will be digitally implemented in the future to streamline curation of experimental results and bridge the gaps among anatomists, imagers, and neuroinformatics databases.

  8. Descriptive Feedback; Increasing Teacher Awareness, Adapting Research Techniques.

    ERIC Educational Resources Information Center

    Kepler, Karen B.

    This study investigated the ability of middle school teachers to use descriptive feedback from their students in changing their teaching behavior. One homeroom group of twenty-five students was observed in interaction with nine teachers of math, English, social studies, and science over a one-year period to elicit both quantifiable and qualitative…

  9. The first organ-based free ontology for arthropods (Ontology of Arthropod Circulatory Systems - OArCS) and its integration into a novel formalization scheme for morphological descriptions.

    PubMed

    Wirkner, Christian S; Göpel, Torben; Runge, Jens; Keiler, Jonas; Klussmann-Fricke, Bastian-Jesper; Huckstorf, Katarina; Scholz, Stephan; Mikó, Istvan; Yoder, Matt; Richter, Stefan

    2017-01-25

    Morphology, the oldest discipline in the biosciences, is currently experiencing a renaissance in the field of comparative phenomics. However, morphological/phenotypic research still suffers on various levels from a lack of standards. This shortcoming, first highlighted as the "linguistic problem of morphology", concerns the usage of terminology but also the need for formalization of morphological descriptions themselves, something of paramount importance not only to the field of morphology but also when it comes to the use of phenotypic data in systematics and evolutionary biology. We therefore argue, that for morphological descriptions, the basis of all systematic and evolutionary interpretations, ontologies need to be utilized which are based exclusively on structural qualities/properties and which in no case include statements about homology and/or function. Statements about homology and function constitute interpretations on a different or higher level. Based on these 'anatomy ontologies', further ontological dimensions (e.g. referring to functional properties or homology) may be exerted for a broad use in evolutionary phenomics. To this end we present the first organ-based ontology for the most species-rich animal group, the Arthropoda. Our Ontology of Arthropod Circulatory Systems (OArCS) contains a comprehensive collection of 383 terms (i.e. sups) tied to 296 concepts (i.e. definitions) collected from the literature on phenotypic aspects of circulatory organ features in arthropods. All of the concepts used in OArCS are based exclusively on structural features, and in the context of the ontology are independent of homology and functional assumptions. We cannot rule out that in some cases, terms are used which in traditional usage and previous accounts might have implied homology and/or function, e.g. heart, sternal artery. Concepts are composed of descriptive elements that are used to classify observed instances into the organizational framework of the

  10. Mapping of Primary Instructional Methods and Teaching Techniques for Regularly Scheduled, Formal Teaching Sessions in an Anesthesia Residency Program.

    PubMed

    Vested Madsen, Matias; Macario, Alex; Yamamoto, Satoshi; Tanaka, Pedro

    2016-06-01

    In this study, we examined the regularly scheduled, formal teaching sessions in a single anesthesiology residency program to (1) map the most common primary instructional methods, (2) map the use of 10 known teaching techniques, and (3) assess if residents scored sessions that incorporated active learning as higher quality than sessions with little or no verbal interaction between teacher and learner. A modified Delphi process was used to identify useful teaching techniques. A representative sample of each of the formal teaching session types was mapped, and residents anonymously completed a 5-question written survey rating the session. The most common primary instructional methods were computer slides-based classroom lectures (66%), workshops (15%), simulations (5%), and journal club (5%). The number of teaching techniques used per formal teaching session averaged 5.31 (SD, 1.92; median, 5; range, 0-9). Clinical applicability (85%) and attention grabbers (85%) were the 2 most common teaching techniques. Thirty-eight percent of the sessions defined learning objectives, and one-third of sessions engaged in active learning. The overall survey response rate equaled 42%, and passive sessions had a mean score of 8.44 (range, 5-10; median, 9; SD, 1.2) compared with a mean score of 8.63 (range, 5-10; median, 9; SD, 1.1) for active sessions (P = 0.63). Slides-based classroom lectures were the most common instructional method, and faculty used an average of 5 known teaching techniques per formal teaching session. The overall education scores of the sessions as rated by the residents were high.

  11. Formal and informal organizational activities of people who inject drugs in New York City: description and correlates.

    PubMed

    Friedman, Samuel R; Pouget, Enrique R; Sandoval, Milagros; Jones, Yolanda; Mateu-Gelabert, Pedro

    2015-01-01

    Little is known about group memberships of people who inject drugs (PWID). Three hundred PWID were interviewed about formal and informal group participation and risk behaviors. Many took part in groups related to problems and resources associated with injecting drugs, religion, sports or gender. Harm reduction group and support group participation was associated with less risk behavior; sports groups participation with more risk behavior. Group involvement by PWID may be important to their lives and/or affect prevention or infectious disease transmission. More research is needed about determinants and consequences of their and other drug users' group memberships.

  12. Formal and informal organizational activities of people who inject drugs in New York City: Description and correlates

    PubMed Central

    Friedman, Samuel R.; Pouget, Enrique R.; Sandoval, Milagros; Jones, Yolanda; Mateu-Gelabert, Pedro

    2014-01-01

    Background Little is known about group memberships of people who inject drugs. Methods We interviewed 300 injectors about formal and informal group participation and risk behaviors. Results Many took part in groups related to problems and resources associated with injecting drugs, religion, sports or gender. Harm reduction group and support group participation was associated with less risk behavior; sports groups participation with more risk behavior. Discussion Group involvement by people who inject drugs may be important to their lives and/or affect prevention or infectious disease transmission. More research is needed about determinants and consequences of their and other drug users’ group memberships. PMID:25774744

  13. Cystoscopic-assisted partial cystectomy: description of technique and results

    PubMed Central

    Gofrit, Ofer N; Shapiro, Amos; Katz, Ran; Duvdevani, Mordechai; Yutkin, Vladimir; Landau, Ezekiel H; Zorn, Kevin C; Hidas, Guy; Pode, Dov

    2014-01-01

    Background Partial cystectomy provides oncological results comparable with those of radical cystectomy in selected patients with invasive bladder cancer without the morbidity associated with radical cystectomy and urinary diversion. We describe a novel technique of partial cystectomy that allows accurate identification of tumor margins while minimizing damage to the rest of the bladder. Methods During the study period, 30 patients underwent partial cystectomy for invasive high-grade cancer. In 19 patients, the traditional method of tumor identification was used, ie, identifying the tumor by palpation and cystotomy. In eleven patients, after mobilization of the bladder, flexible cystoscopy was done and the light of the cystoscope was pointed toward one edge of the planned resected ellipse around the tumor, thus avoiding cystotomy. Results Patients who underwent partial cystectomy using the novel method were similar in all characteristics to patients operated on using the traditional technique except for tumor diameter which was significantly larger in patients operated on using the novel method (4.3±1.5 cm versus 3.11±1.18 cm, P=0.032). Complications were rare in both types of surgery. The 5-year local recurrence-free survival was marginally superior using the novel method (0.8 versus 0.426, P=0.088). Overall, disease-specific and disease-free survival rates were similar. Conclusion The use of a flexible cystoscope during partial cystectomy is a simple, low-cost maneuver that assists in planning the bladder incision and minimizes injury to the remaining bladder by avoiding the midline cystotomy. Initial oncological results show a trend toward a lower rate of local recurrence compared with the standard method. PMID:25368846

  14. A two-column formalism for time-dependent modelling of stellar convection. I. Description of the method

    NASA Astrophysics Data System (ADS)

    Stökl, A.

    2008-11-01

    Context: In spite of all the advances in multi-dimensional hydrodynamics, investigations of stellar evolution and stellar pulsations still depend on one-dimensional computations. This paper devises an alternative to the mixing-length theory or turbulence models usually adopted in modelling convective transport in such studies. Aims: The present work attempts to develop a time-dependent description of convection, which reflects the essential physics of convection and that is only moderately dependent on numerical parameters and far less time consuming than existing multi-dimensional hydrodynamics computations. Methods: Assuming that the most extensive convective patterns generate the majority of convective transport, the convective velocity field is described using two parallel, radial columns to represent up- and downstream flows. Horizontal exchange, in the form of fluid flow and radiation, over their connecting interface couples the two columns and allows a simple circulating motion. The main parameters of this convective description have straightforward geometrical meanings, namely the diameter of the columns (corresponding to the size of the convective cells) and the ratio of the cross-section between up- and downdrafts. For this geometrical setup, the time-dependent solution of the equations of radiation hydrodynamics is computed from an implicit scheme that has the advantage of being unaffected by the Courant-Friedrichs-Lewy time-step limit. This implementation is part of the TAPIR-Code (short for The adaptive, implicit RHD-Code). Results: To demonstrate the approach, results for convection zones in Cepheids are presented. The convective energy transport and convective velocities agree with expectations for Cepheids and the scheme reproduces both the kinetic energy flux and convective overshoot. A study of the parameter influence shows that the type of solution derived for these stars is in fact fairly robust with respect to the constitutive numerical

  15. The Effect of Cooperative Integrated Reading and Composition Technique on Students' Reading Descriptive Text Achievement

    ERIC Educational Resources Information Center

    Zainuddin

    2015-01-01

    This study was aimed at finding out the effectiveness of applying Cooperative Integrated Reading and Composition (CIRC) Technique on Students' Reading Descriptive Text Achievement. In other words, the objective of this study was to find out if there was a significant effect of applying Cooperative Integrated Reading and Composition (CIRC)…

  16. Recommended procedures and techniques for the petrographic description of bituminous coals

    USGS Publications Warehouse

    Chao, E.C.T.; Minkin, J.A.; Thompson, C.L.

    1982-01-01

    bed. The use of bulk-specific-gravity determinations is alo recommended for identification and characterization of the distinctive lithologic units. The availability of an AIAS also enhances the capability to acquire textural information. Ranges of size of maceral and mineral grains can be quickly and precisely determined by use of an AIAS. We assume that shape characteristics of coal particles can also be readily evaluated by automated image analysis, although this evaluation has not yet been attempted in our laboratory. Definitive data on the particulate mineral content of coal constitute another important segment of petrographic description. Characterization of mineral content may be accomplished by optical identification, electron microprobe analysis, X-ray diffraction, and scanning and transmission electron microscopy. Individual mineral grains in place in polished blocks or polished this sections, or separated from the coal matrix by sink-float methods are studied by analytical techniques appropriate to the conditions of sampling. Finally, whenever possible, identification of the probable genus or plant species from which a given coal component is derived will add valuable information and meaning to the petrographic description. ?? 1982.

  17. SEVERE VALGUS DEFORMITY OF THE KNEE: DESCRIPTION OF NEW SURGICAL TECHNIQUE FOR ITS CORRECTION

    PubMed Central

    da Silva, Robson Rocha; Matos, Marcos Almeida; Pimentel, Maurício; Martins, Bruno Jacomeli; Oliveira, Rafael Valadares

    2015-01-01

    Varus supracondylar osteotomy of the femur is the established procedure for treating painful knees that present lateral arthrosis and valgus deformity. In descriptions of the conventional surgical techniques, there are divergences regarding the location, access route, correction level, fixation type and area for synthesis insertion. This is most evident in cases of severe valgus with angles greater than 30° and distal femoral deformation, in association with hypoplasia of the lateral condyle. The authors describe a new surgical technique for distal femoral osteotomy, based on anatomical and geometrical criteria, which was developed in their clinic for treating severe valgus cases, and they present one of the cases treated. In the new technique, the wedge to be surgically resected has an oblique direction and the format of an isosceles triangle. This new proposal thus seeks to resolve problems that have been presented in such cases, through enabling valgus correction without causing any new deformity of the distal femur. Good cortical bone contact is promoted, and application of a stable synthesis system is made easier. However, the age limits for such patients and the degree of knee arthrosis that might contraindicate this procedure remain unknown. Hence, a larger sample and longer follow-up for operated cases are required. PMID:27042630

  18. Benign paroxysmal positioning vertigo: classic descriptions, origins of the provocative positioning technique, and conceptual developments.

    PubMed

    Lanska, D J; Remler, B

    1997-05-01

    The original description of benign paroxysmal positioning vertigo (BPPV) has been variously attributed to Bárány, Adler, and others. In addition, the proper eponymic designation for the provocative positioning test used to diagnose BPPV has been unclear, because authors use a variety of different terms, including Bárány, Nylén-Bárány, Nylén, Hallpike, Hallpike-Dix, and Dix-Hallpike to refer to the procedure in current use. Based on a review of the extant medical literature, Bárány was the first to describe the condition in detail, and Dix and Hallpike were the first to clearly describe both the currently used provocative positioning technique and the essential clinical manifestations of benign paroxysmal positioning vertigo elicited by that technique. Nevertheless, despite their important contributions, neither Bárány nor Dix and Hallpike understood the pathophysiology of BPPV nor did they appreciate that the positioning techniques they used actually demonstrated pathology in the semicircular canals rather than the utricle. The modern understanding of the pathophysiology of BPPV began with Schuknecht's proposal that the dysfunction resulted from the gravity-dependent movement of loose or fixed dense material within the posterior semicircular canal ("cupulolithiasis"). Although Schuknecht's formulations were not consistent with all clinical features of the disease, they led to the modern "canalolithiasis theory" and highly effective canalith repositioning or "liberatory" maneuvers for BPPV.

  19. Innovative techniques for the description of reservoir heterogeneity using tracers. Final report, October 1992--December 1993

    SciTech Connect

    Pope, G.A.; Sepehrnoori, K.; Delshad, M.; Ferreira, L.; Gupta, A.; Maroongroge, V.

    1994-11-01

    This is the final report of a three year research project on the use of tracers for reservoir characterization. The objective of this research was to develop advanced, innovative techniques for the description of reservoir characteristics using both single-well backflow and interwell tracer tests. (1) The authors implemented and validated tracer modeling features in a compositional simulator (UTCOMP). (2) They developed and applied a new single well tracer test for estimating reservoir heterogeneity. (3) They developed and applied a new single well tracer test for estimating reservoir wettability in-situ. (4) They developed a new, simple and efficient method to analyze two well tracer tests based upon type curve matching and illustrated its use with actual field tracer data. (5) They developed a new method for deriving an integrated reservoir description based upon combinatorial optimization schemes. (6) They developed a new, interwell tracer test for reservoir heterogeneity called vertical tracer profiling (VTP) and demonstrated its advantages over conventional interwell tracer testing. (7) They developed a simple and easy analytical method to estimate swept pore volume from interwell tracer data and showed both the theoretical basis for this method and its practical utility. (8) They made numerous enhancements to our compositional reservoir simulator such as including the full permeability tensor, adding faster solvers, improving its speed and robustness and making it easier to use (better I/0) for tracer simulation problems. (9) They applied the enhanced version of UTCOMP to the analysis of interwell tracer data using perfluorocarbons at Elks Hill Naval Petroleum Reserve. All of these accomplishments taken together have significantly improved the state of reservoir tracer technology and have demonstrated that it is a far more powerful and useful tool for quantitative reservoir characterization than previously realized or practiced by the industry.

  20. Formalizing Space Shuttle Software Requirements

    NASA Technical Reports Server (NTRS)

    Crow, Judith; DiVito, Ben L.

    1996-01-01

    This paper describes two case studies in which requirements for new flight-software subsystems on NASA's Space Shuttle were analyzed, one using standard formal specification techniques, the other using state exploration. These applications serve to illustrate three main theses: (1) formal methods can complement conventional requirements analysis processes effectively, (2) formal methods confer benefits regardless of how extensively they are adopted and applied, and (3) formal methods are most effective when they are judiciously tailored to the application.

  1. Formalisms for Electron Exchange Kinetics in Aqueous Solution, and the Role of Ab Initio Techniques in Their Implementation

    SciTech Connect

    Newton, M. D.

    1980-01-01

    Formalisms suitable for calculating the rate of electron exchange between transition metal complexes in aqueous solution are reviewed and implemented in conjunction with ab initio quantum chemical calculations which provide crucial off-diagonal Hamiltonian matrix elements as well as other relevant electronic structural data. Rate constants and activation parameters are calculated for the hex-aquo Fe2 +-Fe3+ system, using a simple activated complex theory, a non-adiabatic semi-classical model which includes nuclear tunnelling, and a more detailed quantum mechanical method based on the Golden Rule. Comparisons are made between calculated results and those obtained by extrapolating experimental data to zero ionic strength. All methods yield similar values for the overall rate constant (∾ 0.1 L/(mol-sec)). The experimental activation parameters (δH and δS) are in somewhat better agreement with the semi classical and quantum mechanical results than with those from the simple activated complex theory, thereby providing some indication that non-adiabaticity and nuclear tunnelling may be important in the Fe2+/3+ exchange reaction. It is concluded that a model based on direct metal-metal overlap can account for the observed reaction kinetics provided the reactants are allowed to approach well within the traditional contact distance of 6.9 Å. 6 figures, 7 tables.

  2. Formalizing Probabilistic Safety Claims

    NASA Technical Reports Server (NTRS)

    Herencia-Zapana, Heber; Hagen, George E.; Narkawicz, Anthony J.

    2011-01-01

    A safety claim for a system is a statement that the system, which is subject to hazardous conditions, satisfies a given set of properties. Following work by John Rushby and Bev Littlewood, this paper presents a mathematical framework that can be used to state and formally prove probabilistic safety claims. It also enables hazardous conditions, their uncertainties, and their interactions to be integrated into the safety claim. This framework provides a formal description of the probabilistic composition of an arbitrary number of hazardous conditions and their effects on system behavior. An example is given of a probabilistic safety claim for a conflict detection algorithm for aircraft in a 2D airspace. The motivation for developing this mathematical framework is that it can be used in an automated theorem prover to formally verify safety claims.

  3. [A formal description of mammals' behavior based on data on snow tracking, with pine marten (Martes martes) as a case study].

    PubMed

    Vladimirova, É D; Morozov, V V

    2014-01-01

    The formalism allowing to describe animals' behavior is based on the model of informational interactions between an animal and its environment. The model may be represented as an assemblage consisting of two blocks. The first block, which corresponds to the perception system, is a probabilistic operator: it selects an object of certain class out of many objects randomly encountered by an animal while it moves around. The selected object keeps its actuality as an input symbol for the second block of the assemblage during one or several cycles of the block operation. The second block, being afinite structural probabilistic automaton, generates output reactions to the input symbol. The structural automaton, which consists of elementary automata, produces a sequence of output reactions in course of interactions with the selected object: After exhaustion of the previous input actuality, the assemblage moves to the next cycle. At that, the probabilistic operator comes back to the receptive state and produces next output. Automaton "inputs" correspond to objects of certain classes, selectively perceived by an animal; "outputs" correspond to a sequence of elementary motor reactions. Based on data on snow tracking of pine marten foraging activity, there have been composed: the assemblage input and output alphabets, a conjugation matrix of input signals and internal states of the first elementary automaton that is contained in the second block structure, and transition probability matrices for the states of the second block elementary automata, which are defined for a class of environmental objects when foraging activity occurs. The proposed formalism makes it possible to convert field data on tracking into the unified form, detect key circumstances of animals' behavioral activity, and analyze this natural phenomenon in detail.

  4. Line group techniques in description of the structural phase transitions in some superconductors

    NASA Technical Reports Server (NTRS)

    Meszaros, CS.; Balint, A.; Bankuti, J.

    1995-01-01

    The main features of the theory of line groups, and their irreducible representations are briefly discussed, as well as the most important applications of them. A new approach in the general symmetry analysis of the modulated systems is presented. It is shown, that the line group formalism could be a very effective tool in the examination of the structural phase transitions in High Temperature SUperconductors. As an example, the material YBa2Cu3O(7-x) is discussed briefly.

  5. Academic Staff's Apathy towards Formal Professional Development Programmes at North West University

    ERIC Educational Resources Information Center

    Makunye, M. M.; Pelser, T. G.

    2012-01-01

    The purpose of this study was to explore reasons for academics' apathy towards formal professional development programmes at North-West University. The research design was essentially descriptive, employing both qualitative and quantitative research techniques to gather and analyse data. Three techniques, namely, questionnaire surveys, analysis of…

  6. A Formal Re-Description of the Cockroach Hebardina concinna Anchored on DNA Barcodes Confirms Wing Polymorphism and Identifies Morphological Characters for Field Identification

    PubMed Central

    Yue, Qiaoyun; Wu, Keliang; Qiu, Deyi; Hu, Jia; Liu, Dexing; Wei, Xiaoya; Chen, Jian; Cook, Charles E.

    2014-01-01

    Background Hebardina concinna is a domestic pest and potential vector of pathogens throughout East and Southeast Asia, yet identification of this species has been difficult due to a lack of diagnostic morphological characters, and to uncertainty in the relationship between macroptyrous (long-winged) and brachypterous (small-winged) morphotypes. In insects male genital structures are typically species-specific and are frequently used to identify species. However, male genital structures in H. concinna had not previously been described, in part due to difficulty in identifying conspecifics. Methods/Principal Findings We collected 15 putative H. concinna individuals, from Chinese populations, of both wing morphotypes and both sexes and then generated mitochondrial COI (the standard barcode region) and COII sequences from five of these individuals. These confirmed that both morphotypes of both sexes are the same species. We then dissected male genitalia and compared genital structures from macropterous and brachypterous individuals, which we showed to be identical, and present here for the first time a detailed description of H. concinna male genital structures. We also present a complete re-description of the morphological characters of this species, including both wing morphs. Conclusions/Significance This work describes a practical application of DNA barcoding to confirm that putatively polymorphic insects are conspecific and then to identify species-specific characters that can be used in the field to identify individuals and to obviate the delay and cost of returning samples to a laboratory for DNA sequencing. PMID:25232993

  7. Rethinking Formalisms in Formal Education

    ERIC Educational Resources Information Center

    Nathan, Mitchell J.

    2012-01-01

    I explore a belief about learning and teaching that is commonly held in education and society at large that nonetheless is deeply flawed. The belief asserts that mastery of "formalisms"--specialized representations such as symbolic equations and diagrams with no inherent meaning except that which is established by convention--is prerequisite to…

  8. Line group techniques in description of the structural phase transitions in some superconductors

    SciTech Connect

    Meszaros, C.; Bankuti, J.; Balint, A.

    1994-12-31

    The main features of the theory of line groups, and their irreducible representations are briefly discussed, as well as the most important applications of them. A new approach in the general symmetry analysis of the modulated systems is presented. It is shown, that the line group formalism could be a very effective tool in the examination of the structural phase transitions in High Temperature Superconductors. As an example, the material YBa{sub 2}Cu{sub 3}O{sub 7-x} is discussed briefly.

  9. Beyond formalism

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1991-01-01

    The ongoing debate over the role of formalism and formal specifications in software features many speakers with diverse positions. Yet, in the end, they share the conviction that the requirements of a software system can be unambiguously specified, that acceptable software is a product demonstrably meeting the specifications, and that the design process can be carried out with little interaction between designers and users once the specification has been agreed to. This conviction is part of a larger paradigm prevalent in American management thinking, which holds that organizations are systems that can be precisely specified and optimized. This paradigm, which traces historically to the works of Frederick Taylor in the early 1900s, is no longer sufficient for organizations and software systems today. In the domain of software, a new paradigm, called user-centered design, overcomes the limitations of pure formalism. Pioneered in Scandinavia, user-centered design is spreading through Europe and is beginning to make its way into the U.S.

  10. Robust video communication by combining scalability and multiple description coding techniques

    NASA Astrophysics Data System (ADS)

    Wang, Huisheng; Ortega, Antonio

    2003-05-01

    Layered coding (LC) and multiple description coding (MDC) have been proposed as two different kinds of 'quality adaptation' schemes for video delivery over the current Internet or wireless networks. To combine the advantages of LC and MDC, we present a new approach -- Multiple Description Layered Coding (MDLC), to provide reliable video communication over a wider range of network scenarios and application requirements. MDLC improves LC in that it introduces redundancy in each layer so that the chance of receiving at least one description of base layer is greatly enhanced. Though LC and MDC are each good in limit cases (e.g., long end-to-end delay for LC vs. short delay for MDC), the proposed MDLC system can address intermediate cases as well. Same as a LC system with retransmission, the MDLC system can have a feedback channel to indicate which descriptions have been correctly received. Thus a low redundancy MDLC system can be implemented with our proposed runtime packet scheduling system based on the feedback information. The goal of our scheduling algorithm is to find a proper on-line packet scheduling policy to maximize the playback quality at the decoder. Previous work on scheduling algorithms has not considered multiple decoding choices due to the redundancy between data units, because of the increase in complexity involved in considering alternate decoding paths. In this paper, we introduce a new model of Directed Acyclic HyperGraph (DAHG) to represent the data dependencies among frames and layers, as well as the data correlation between descriptions. The impact of each data unit to others is represented by messages passing along the graph with updates based on new information received. Experimental results show that the proposed system provides more robust and efficient video communication for real-time applications over lossy packet networks.

  11. The “Purse-string” Technique for Shoulder Stabilization, Description of the Technique, Long term Results and Literature Review

    PubMed Central

    Arealis, Georgios; Rodrigues, Joana Bento; Hope, Natalie; Levy, Ofer

    2017-01-01

    Background: Over the last 2 decades arthroscopic stabilization and Bankart repair has gained popularity due to the advances in materials and surgical techniques. Results of arthroscopic stabilization have been similar to open without the risks of it. The number of anchors used has been suggested to be very important in “spot-weld” arthroscopic stabilization however the “purse-string” technique (PST) can achieve similar results using only one anchor. We describe technique and long term results from using the PST and search the literature for other papers regarding PST. Methods: Between 2003 and 2013 a total of 193 patients were operated. Patients included those with anterior instability. Using PubMed relevant studies reporting results of PST were identified. Results: Mean follow up was 2 (range 0.5 to 3) years. 9 (4.7%) patients experienced recurrent instability. Almost all patients (97%) returned to their sporting and leisure activities and all professional athletes went back to the same sport. One more UK centre reported 6.1% recurrence in 114 patients at 4 years follow up. These results are similar to the published 11% recurrence of instability after “spot-weld” arthroscopic techniques at 11 years clinical follow-up. Conclusion: This study indicates that PST is safe and effective alternative method for the treatment of anterior shoulder instability. In this technique with one anchor simultaneous repair of labrum, creation of an anterior bumper and capsular shift can be achieved. It has the advantage of being cheaper, faster yet efficient with good long term results and leaves space for revision anchors in case of recurrence.

  12. Formal verification of AI software

    NASA Technical Reports Server (NTRS)

    Rushby, John; Whitehurst, R. Alan

    1989-01-01

    The application of formal verification techniques to Artificial Intelligence (AI) software, particularly expert systems, is investigated. Constraint satisfaction and model inversion are identified as two formal specification paradigms for different classes of expert systems. A formal definition of consistency is developed, and the notion of approximate semantics is introduced. Examples are given of how these ideas can be applied in both declarative and imperative forms.

  13. Total cysto-prostatectomy: Technique description and results in 2 dogs.

    PubMed

    Bacon, Nicholas; Souza, Carlos H de M; Franz, Sarah

    2016-02-01

    We describe a novel technique for total cysto-prostatectomy, followed by uretero-urethral anastomosis in 2 dogs. The technique was successful and was performed without pubic osteotomy. Post-operative urinary tract infections may be a potentially serious event.

  14. A descriptive analysis of batting backlift techniques in cricket: Does the practice of elite cricketers follow the theory?

    PubMed

    Noorbhai, M Habib; Noakes, Timothy D

    2016-10-01

    One of the first principles of cricket batsmanship that is coached from a young age is to play with a straight bat. Limited studies to date have examined whether top international batsmen use this traditionally described technique. Accordingly, we performed a descriptive, observational study of the backlift technique adopted by 65 of the most successful batsmen of all time, based on their career averages, strike rate and runs scored. The batsmen were divided into two groups depending on whether they played the game before or after 1954. Surprisingly, more than 70% of these successful batsmen did not adopt the traditionally taught technique. Instead, they adopted a more looped action in which the initial movement of the bat was in the direction of the slips, and in extreme cases it was either towards the gully/point region or to have the face of the bat directed towards the off-side. This suggests that traditionally taught batting coaching techniques may hinder, rather than enhance future cricketing performance. Since the vast majority of cricketers are not coached in this technique, this finding probably indicates that this looped technique is likely a contributing factor to effective batsmanship.

  15. Monitoring of Land Subsidence in Ravenna Municipality Using Integrated SAR - GPS Techniques: Description and First Results

    NASA Astrophysics Data System (ADS)

    Artese, G.; Fiaschi, S.; Di Martire, D.; Tessitore, S.; Fabris, M.; Achilli, V.; Ahmed, A.; Borgstrom, S.; Calcaterra, D.; Ramondini, M.; Artese, S.; Floris, M.; Menin, A.; Monego, M.; Siniscalchi, V.

    2016-06-01

    The Emilia Romagna Region (N-E Italy) and in particular the Adriatic Sea coastline of Ravenna, is affected by a noticeable subsidence that started in the 1950s, when the exploitation of on and off-shore methane reservoirs began, along with the pumping of groundwater for industrial uses. In such area the current subsidence rate, even if lower than in the past, reaches the -2 cm/y. Over the years, local Authorities have monitored this phenomenon with different techniques: spirit levelling, GPS surveys and, more recently, Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques, confirming the critical situation of land subsidence risk. In this work, we present the comparison between the results obtained with DInSAR and GPS techniques applied to the study of the land subsidence in the Ravenna territory. With regard to the DInSAR, the Small Baseline Subset (SBAS) and the Coherent Pixel Technique (CPT) techniques have been used. Different SAR datasets have been exploited: ERS-1/2, ENVISAT, TerraSAR-X and Sentinel-1. Some GPS campaigns have been also carried out in a subsidence prone area. 3D vertices have been selected very close to existing persistent scatterers in order to link the GPS measurement results to the SAR ones. GPS data were processed into the International reference system and the comparisons between the coordinates, for the first 6 months of the monitoring, provided results with the same trend of the DInSAR data, even if inside the precision of the method.

  16. Difficult Removal of Retrievable IVC Filters: A Description of the 'Double-Wire Restraining' Technique

    SciTech Connect

    Owens, Charles A. Bui, James T. Knuttinen, M.-Grace Emmanuel, Neelmini Carrillo, Tami C. Gaba, Ron C.

    2011-02-15

    We describe our experience with the use of the 'double-wire restraining' technique to assist in the removal of two retrievable inferior vena cava filters: one had been misplaced in the right brachiocephalic vein with apex perforation of the vessel wall, and the second filter had migrated cephalad to straddle across both renal veins. The 'double-wire restraining' technique consists of two stiff-shaft Glidewires (Terumo, Somerset, NJ) placed through the same introducer sheath and positioned on opposite sides of the filter. Both wires restrain the filter at the tip of the sheath as the sheath is advanced, thus allowing the operator to reposition the filter. This report details how this technique was used to realign two malpositioned filters and reposition the filter apices from their extravascular location, thus exposing them for ensnarement.

  17. Single-Incision Laparoscopy Surgery Excision of an Infected Urachal Cyst: Description of the Technique

    PubMed Central

    Garisto, Juan D.; Pimentel M., Edwin E.

    2017-01-01

    Abstract Background: Urachal cysts (UCs) are secondary to incomplete obliteration of the embryonic urachal duct and may become symptomatic when infected. Treatment is primarily surgical to excise the infected cyst. Surgical approaches include a lower midline laparotomy or minimally invasive (MI) techniques. Case: We present a case of a young male with an infected UC that was treated with a single-incision laparoscopy surgery. The operative technique is described. Conclusion: This approach is a safe and feasible option for the MI management of UCs. PMID:28164161

  18. CAD/CAM silicone simulator for teaching cheiloplasty: description of the technique.

    PubMed

    Zheng, Y; Lu, B; Zhang, J; Wu, G

    2015-02-01

    Techniques of virtual simulation have been used to teach junior surgeons how to do a cheiloplasty, but still do not meet the trainees' demands. We describe a CAD/CAM silicone simulator, which we made using several maxillofacial prosthetic techniques. An optical scanning system was used to collect the data about the cleft lip. Reverse engineering software was then used to build the virtual model, and this was processed in wax by machine. The definitive simulator was made with prosthetic silicone and extrinsic colourants. The surgical trainees practised the basic skills of cheiloplasty on the simulator, and proved its worth.

  19. Toward integration of systems biology formalism: the gene regulatory networks case.

    PubMed

    Gentilini, Raffaella

    2005-01-01

    We consider the problem of integrating different systems biology formalisms, namely, the process calculi based formalism, the modeling approach based on systems of differential equations, and the one relying on automata-like descriptions (and model checking). Specifically, we define automatic procedures for translating stochastic pi-calculus descriptions of gene regulatory networks to S-systems differential equations. Tools for extracting and reasoning on (approximate) solutions of S-systems have been recently developed in the literature, and can be exploited to establish a link with automata-based systems biology and model checking techniques.

  20. Impression of multiple implants using photogrammetry: Description of technique and case presentation

    PubMed Central

    Peñarrocha-Oltra, David; Agustín-Panadero, Rubén; Bagán, Leticia; Giménez, Beatriz

    2014-01-01

    Aim: To describe a technique for registering the positions of multiple dental implants using a system based on photogrammetry. A case is presented in which a prosthetic treatment was performed using this technique. Study Design: Three Euroteknika® dental implants were placed to rehabilitate a 55-year-old male patient with right posterior maxillary edentulism. Three months later, the positions of the implants were registered using a photogrammetry-based stereo-camera (PICcamera®). After processing patient and implant data, special abutments (PICabutment®) were screwed onto each implant. The PICcamera® was then used to capture images of the implant positions, automatically taking 150 images in less than 60 seconds. From this information a file was obtained describing the relative positions – angles and distances – of each implant in vector form. Information regarding the soft tissues was obtained from an alginate impression that was cast in plaster and scanned. A Cr-Co structure was obtained using CAD/CAM, and its passive fit was verified in the patient’s mouth using the Sheffield test and the screw resistance test. Results and Conclusions: Twelve months after loading, peri-implant tissues were healthy and no marginal bone loss was observed. The clinical application of this new system using photogrammetry to record the position of multiple dental implants facilitated the rehabilitation of a patient with posterior maxillary edentulism by means of a prosthesis with optimal fit. The prosthetic process was accurate, fast, simple to apply and comfortable for the patient. Key words:Dental implants, photogrammetry, dental impression technique, CAD/CAM. PMID:24608216

  1. Electromyogram (EMG) recordings from the subscapularis muscle: description of a technique.

    PubMed

    Németh, G; Kronberg, M; Broström, L A

    1990-01-01

    Operative treatments for recurrent dislocation of the shoulder usually focus on the subscapularis muscle because it is supposed to contribute to the joint stability. It is of clinical interest to record the EMG from the subscapularis muscle in order to interpret its function. The purpose of the present study was to describe a safe and reliable route to reach the muscle, deeply located between the scapula and the thoracic cage, with fine-wire EMG electrodes. Twenty-four shoulders were investigated in 12 volunteers. A hypodermic needle containing bipolar fine-wire electrodes was inserted in the posterior axillary line with the subjects in the supine position, and the arm held in an abducted and externally rotated position. Three criteria confirmed the location of the electrodes: experience of periosteal pain when the needle reached the costal surface of the scapula, drawing-in of the wires 3-4 cm when the subject adducted his arm, thereby rotating his scapula downward, and raw EMG recorded during typical movements. Additionally, in four shoulders, the electrode location was checked with computed tomography. There were no complications from this technique, and the subjects felt no pain from the fine-wire electrodes during arm movements. We conclude that the described technique is a safe and reliable method of reaching the subscapularis muscle with EMG electrodes.

  2. Single-incision-two port laparoscopic tubal ligation: A cost comparison and technique description

    PubMed Central

    Taşdemir, Nicel; Abalı, Remzi; Çelik, Cem; Aksu, Erson; Akkuş, Didem

    2015-01-01

    Objective Laparoscopic surgery is the principal minimally invasive technique that is used for the treatment of gynecologic pathologies. The single-incision laparoscopic surgery (SILS) is another innovation in minimally invasive medicine. The cost of the procedure correlates with the fundamental materials used to access the abdominal cavity and utilize trocars. Material and Methods We applied the single-incision tubal ligation procedure to three patients. A 15–20-mm vertical incision was made in the umbilicus. Two trocars were inserted through the same incision at different fascial regions after insufflation of the abdomen. A 5-mm bipolar cautery was introduced through the accessory trocar, and the mid-portion of the tubes was coagulated and cut bilaterally. Results The postoperative periods of the three patients were uneventful. All patients were discharged on the day of surgery. No major or minor complications occurred. Conclusion The cost for the abdominal access will drop about 82%. When we consider the low pricing for the tubal ligation procedure, the single-incision technique will be more applicable by this method. Moreover, patients will have the advantages of single-incision laparoscopic surgery with low cost. PMID:25788846

  3. A Description of the Revised ATHEANA (A Technique for Human Event Analysis)

    SciTech Connect

    FORESTER,JOHN A.; BLEY,DENNIS C.; COOPER,SUSANE; KOLACZKOWSKI,ALAN M.; THOMPSON,CATHERINE; RAMEY-SMITH,ANN; WREATHALL,JOHN

    2000-07-18

    This paper describes the most recent version of a human reliability analysis (HRA) method called ``A Technique for Human Event Analysis'' (ATHEANA). The new version is documented in NUREG-1624, Rev. 1 [1] and reflects improvements to the method based on comments received from a peer review that was held in 1998 (see [2] for a detailed discussion of the peer review comments) and on the results of an initial trial application of the method conducted at a nuclear power plant in 1997 (see Appendix A in [3]). A summary of the more important recommendations resulting from the peer review and trial application is provided and critical and unique aspects of the revised method are discussed.

  4. Test description and preliminary pitot-pressure surveys for Langley Test Technique Demonstrator at Mach 6

    NASA Technical Reports Server (NTRS)

    Everhart, Joel L.; Ashby, George C., Jr.; Monta, William J.

    1992-01-01

    A propulsion/airframe integration experiment conducted in the NASA Langley 20-Inch Mach 6 Tunnel using a 16.8-in.-long version of the Langley Test Technique Demonstrator configuration with simulated scramjet propulsion is described. Schlieren and vapor screen visualization of the nozzle flow field is presented and correlated with pitot-pressure flow-field surveys. The data were obtained at nominal free-stream conditions of Re = 2.8 x 10 exp 6 and a nominal engine total pressure of 100 psia. It is concluded that pitot-pressure surveys coupled to schlieren and vapor-screen photographs, and oil flows have revealed flow features including vortices, free shear layers, and shock waves occurring in the model flow field.

  5. Perfusion Angiography of the Foot in Patients with Critical Limb Ischemia: Description of the Technique

    SciTech Connect

    Jens, Sjoerd Marquering, Henk A.; Koelemay, Mark J. W.; Reekers, Jim A.

    2015-02-15

    ObjectiveTo study the feasibility of 2D perfusion imaging in critical limb ischemia (CLI).Methods/ResultsPerfusion angiography is a new technology which was tested in 18 patients with CLI of the foot. A standardized protocol was used with a catheter placed at the mid-part of the popliteal artery, and a total of 9 cc of non-ionic iodinated contrast material was injected at a rate of 3 cc/sec. The technology is based on early cardiology research where iodinated contrast agents were used for imaging of cardiac perfusion. During the first pass of the contrast, there is a significant diffusion of the contrast agents into the interstitial space, particularly for non-ionic and low-molecular-weight compounds.DiscussionThe original angiography data can be used to make a time–density curve, which represents the actual perfusion of the foot in time. Angiographic perfusion imaging is a post-processing modality for which no extra contrast or radiation is needed. With this technique, it is possible to get more information about the perfusion status and microcirculation of the foot. This is a step toward functional imaging in CLI patients.

  6. The "Hoop" Plate for Posterior Bicondylar Shear Tibial Plateau Fractures: Description of a New Surgical Technique.

    PubMed

    Giordano, Vincenzo; Schatzker, Joseph; Kfuri, Mauricio

    2016-09-29

    High-energy fractures of the proximal tibia with extensive fragmentation of the posterior rim of the tibial plateau are challenging. This technique aims to describe a method on how to embrace the posterior rim of the tibial plateau by placing a horizontal precontoured one-third tubular plate wrapped around its corners. This method, which we named "hoop plating," is mainly indicated for cases of crushed juxta-articular rim fractures, aiming to restore cortical containment of the tibial plateau. Through a lateral approach with a fibular head osteotomy (Lobenhoffer approach), both anterolateral and posterolateral fragments are directly reduced and supported by a one-third tubular plate of adequate length. The plate is inserted from lateral to medial deep to all soft tissues, and its position is checked with fluoroscopy. The implant sits exactly on the posterior cortex of the tibial plateau and provides containment for the reduced juxta-articular posterior cortex and rim. We begin with immediate range of motion. Toe-touch weight-bearing with crutches is allowed with the operated knee in full extension. Weight-bearing is gradually increased only after 6 weeks as bone healing is taking place. Clinical follow-up is performed at 1, 3, 6, and 12 weeks. If the radiological exam confirms that the fracture is healed, the patient is allowed to proceed to muscle strengthening and bear weight entirely. The "hoop plating" may be a good option for the management in cases of extensive posterior tibial plateau articular surface fracture and impaction with rim and posterior cortical wall fragmentation.

  7. Fluoroscopy-Guided Sacroiliac Joint Injection: Description of a Modified Technique.

    PubMed

    Kasliwal, Prasad Jaychand; Kasliwal, Sapana

    2016-02-01

    Sacroiliac joint (SIJ) pathology is a common etiologic cause for 10 - 27% of cases of mechanical low back pain (LBP) below the L5 level. In the absence of definite clinical or radiologic diagnostic criteria, controlled blocks of the SIJ have become the choice assessment method for making the diagnosis of SIJ pain. The SI joint is most often characterized as a large, auricular-shaped, diarthrodial synovial joint. In reality, its synovial characteristic is limited only to the distal third and anterior third. In SIJ interventions, the lateral view has been underutilized. In our technique, we used the lateral view to create a three-dimensional view of the SIJ to aid in gauging the accurateness of the contrast spread and to obtain a precise block. After obtaining appropriate fluoroscopic images, a curved tip spinal needle was directed into the inferior aspect of the SIJ using a posterior approach. As the needle contacts firm tissues on the posterior aspect of the joint, position of the needle tip is checked using lateral fluoroscopy. In the lateral view, the needle tip position is manipulated to keep it in the anterior third of the SIJ and contrast is injected. Our criteria for accurate SIJ block, in posteroanterior (PA) view, is the injection of the contrast medium should outline the joint space and the contrast medium should be seen to travel cephalad along the joint line. In the lateral view, the contrast medium most densely outlines the parameter of the joint. We have utilized this method with good effect in approximately 30 cases over one year. Out of 30 cases, needle position and contrast spread was satisfactory in 28 and 27 cases, respectively. So satisfactory needle placement and contrast spread was in 93% and 87% cases. Pain relief of 80% or more after intra-articular injection of local anesthetic was seen in 50% (15 of 30) patients; pain relief of 50 - 79% was witnessed in 30% (9 of 30) patients. Thus, pain decreased 50% or more in 80% (24 of 30) of the joints

  8. Formal Methods at Intel - An Overview

    NASA Technical Reports Server (NTRS)

    Harrison, John

    2010-01-01

    Since the 1990s, Intel has invested heavily in formal methods, which are now deployed in several domains: hardware, software, firmware, protocols etc. Many different formal methods tools and techniques are in active use, including symbolic trajectory evaluation, temporal logic model checking, SMT-style combined decision procedures, and interactive higher-order logic theorem proving. I will try to give a broad overview of some of the formal methods activities taking place at Intel, and describe the challenges of extending formal verification to new areas and of effectively using multiple formal techniques in combination

  9. An elementary tutorial on formal specification and verification using PVS

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    1993-01-01

    A tutorial on the development of a formal specification and its verification using the Prototype Verification System (PVS) is presented. The tutorial presents the formal specification and verification techniques by way of specific example - an airline reservation system. The airline reservation system is modeled as a simple state machine with two basic operations. These operations are shown to preserve a state invariant using the theorem proving capabilities of PVS. The technique of validating a specification via 'putative theorem proving' is also discussed and illustrated in detail. This paper is intended for the novice and assumes only some of the basic concepts of logic. A complete description of user inputs and the PVS output is provided and thus it can be effectively used while one is sitting at a computer terminal.

  10. Toward the Identification of Styles of Formal Reasoning.

    ERIC Educational Resources Information Center

    Frey, Susan; Bart, William M.

    A method of examining individual variation in responses to Inhelder-Piaget formal reasoning tasks is proposed as a means of identifying cognitive style components of formal reason and as a means of generating more complete descriptions of observable manifestations of formal reasoning. The method is one used by human ethologists and consists of…

  11. The Archival Photograph and Its Meaning: Formalisms for Modeling Images

    ERIC Educational Resources Information Center

    Benson, Allen C.

    2009-01-01

    This article explores ontological principles and their potential applications in the formal description of archival photographs. Current archival descriptive practices are reviewed and the larger question is addressed: do archivists who are engaged in describing photographs need a more formalized system of representation, or do existing encoding…

  12. Prerequisites to Deriving Formal Specifications from Natural Language Requirements.

    DTIC Science & Technology

    1981-10-01

    Special 19. KEY WORDS (Continue on reverse side Ii nocessary and Identify by block number) formal specifications, English specifications, modules, software... English specifications and formal specifications of modules are complementary and since formal specifications require so much effort to write, our...involved four areas of work. The firtt is,A\\ comparing English descriptions with formal specifications of the same software module. This work is now complete

  13. Formal Methods Tool Qualification

    NASA Technical Reports Server (NTRS)

    Wagner, Lucas G.; Cofer, Darren; Slind, Konrad; Tinelli, Cesare; Mebsout, Alain

    2017-01-01

    Formal methods tools have been shown to be effective at finding defects in safety-critical digital systems including avionics systems. The publication of DO-178C and the accompanying formal methods supplement DO-333 allows applicants to obtain certification credit for the use of formal methods without providing justification for them as an alternative method. This project conducted an extensive study of existing formal methods tools, identifying obstacles to their qualification and proposing mitigations for those obstacles. Further, it interprets the qualification guidance for existing formal methods tools and provides case study examples for open source tools. This project also investigates the feasibility of verifying formal methods tools by generating proof certificates which capture proof of the formal methods tool's claim, which can be checked by an independent, proof certificate checking tool. Finally, the project investigates the feasibility of qualifying this proof certificate checker, in the DO-330 framework, in lieu of qualifying the model checker itself.

  14. Formal Methods for Life-Critical Software

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Johnson, Sally C.

    1993-01-01

    The use of computer software in life-critical applications, such as for civil air transports, demands the use of rigorous formal mathematical verification procedures. This paper demonstrates how to apply formal methods to the development and verification of software by leading the reader step-by-step through requirements analysis, design, implementation, and verification of an electronic phone book application. The current maturity and limitations of formal methods tools and techniques are then discussed, and a number of examples of the successful use of formal methods by industry are cited.

  15. The isotropic Hamiltonian formalism

    SciTech Connect

    Vaisman, Izu

    2011-02-10

    A Hamiltonian formalism is a procedure that allows to associate a dynamical system to a function and that includes classical Hamiltonian mechanics as a particular case. The present, expository paper gives a survey of the Hamiltonian formalism defined by an isotropic subbundle of TM+T*M, in particular, by a Dirac structure. We discuss reduction and geometric quantization of the Hamiltonian dynamical systems provided by this formalism.

  16. Software Formal Inspections Guidebook

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Software Formal Inspections Guidebook is designed to support the inspection process of software developed by and for NASA. This document provides information on how to implement a recommended and proven method for conducting formal inspections of NASA software. This Guidebook is a companion document to NASA Standard 2202-93, Software Formal Inspections Standard, approved April 1993, which provides the rules, procedures, and specific requirements for conducting software formal inspections. Application of the Formal Inspections Standard is optional to NASA program or project management. In cases where program or project management decide to use the formal inspections method, this Guidebook provides additional information on how to establish and implement the process. The goal of the formal inspections process as documented in the above-mentioned Standard and this Guidebook is to provide a framework and model for an inspection process that will enable the detection and elimination of defects as early as possible in the software life cycle. An ancillary aspect of the formal inspection process incorporates the collection and analysis of inspection data to effect continual improvement in the inspection process and the quality of the software subjected to the process.

  17. Formality in Rhetorical Delivery.

    ERIC Educational Resources Information Center

    Skopec, Eric Wm.

    Formality in rhetorical delivery can be defined as a complex variable that represents the speaker's efforts to invoke sociocultural rules of audience control through the nonverbal components of the delivery. This document describes some of the aspects of formality, outlines its significance in rhetorical contexts, and evaluates the concept in…

  18. CSR-induced emittance growth in achromats: Linear formalism revisited

    NASA Astrophysics Data System (ADS)

    Venturini, M.

    2015-09-01

    We review the R-matrix formalism used to describe Coherent Synchrotron Radiation (CSR)-induced projected emittance growth in electron beam transport lines and establish the connection with a description in terms of the dispersion-invariant function.

  19. Pedagogical Basis of DAS Formalism in Engineering Education

    ERIC Educational Resources Information Center

    Hiltunen, J.; Heikkinen, E.-P.; Jaako, J.; Ahola, J.

    2011-01-01

    The paper presents a new approach for a bachelor-level curriculum structure in engineering. The approach is called DAS formalism according to its three phases: description, analysis and synthesis. Although developed specifically for process and environmental engineering, DAS formalism has a generic nature and it could also be used in other…

  20. Speechmaking as a Public Relations Technique: A Descriptive Study of Speechmaking Practices and Attitudes Among Selected Public Relations Professionals.

    ERIC Educational Resources Information Center

    Roman, Charles Vasile

    This study surveys speech-making practices and attitudes of practitioners in firms not primarily engaged in providing public relations services. Questionnaires designed to assess the uses of speech making as a public relations technique were sent to the 50 largest United States advertising agencies and to the 34 largest United States business and…

  1. Adhesive measurements of polymer bonded explosive constituents using the JKR experimental technique with a viscoelastic contact description

    NASA Astrophysics Data System (ADS)

    Hamilton, N. R.; Williamson, D. M.; Lewis, D.; Glauser, A.; Jardine, A. P.

    2017-01-01

    It has been shown experimentally that under many circumstances the strength limiting factor of Polymer Bonded Explosives (PBXs) is the adhesion which exists between the filler crystals and the polymer matrix. Experimental measurements of the Work of Adhesion between different binders and glass have been conducted using the JKR experimental technique, a reversible axisymmetric fracture experiment, during which the area of contact and the applied force are both measured during loading and unloading of the interface. The data taken with this technique show a rate dependence not present in the analytical JKR theory which is normally used to describe the adhesive contact of two elastic bodies, and which arises from the viscoelastic properties of the bulk polymer. The data is intended to inform the development, and validate the predictions of, microstructural models of PBX deformation and failure.

  2. Description du comportement sexuel de Calliphora vomitoria (Diptera: Calliphoridae) par une technique d'analyse de textes.

    PubMed

    Campan, M; Le Pape, G; Benziane, T

    1994-04-01

    Description of the sexual behaviour of Calliphora vomitoria (Diptera: Calliphoridae) with a lexical analysis software package. The sexual behaviour of Calliphora vomitoria was described using a lexical analysis software package considering courtship as a series of words, without any arbitrary categorization. Normal as well as manipulated partners of both sexes were presented to the males. Results showed that normal courtship and copulation occurred when the wings were modified but present and correctly oriented, whereas perturbations were observed and copulation disappeared after inversion and various head modifications. Missing elements (head and wings) were less disruptive than their inversion. If the partner was supposed to be scanned from the head to the abdomen via the wings and if it was supposed to perceive the relative position of these different parts, it is obvious that the absence of an element did not act as an error message and courtship and copulation were preserved. On the other hand, inversion of the same elements seemed to induce wrong or inconsistent informations affecting courtship structure, probably because of sequence disturbance. The courtship preservation in front of every kind of manipulation leads us to question what image of the sexual partner is constructed.

  3. Ultrasound-Guided Trigger Point Injection for Serratus Anterior Muscle Pain Syndrome: Description of Technique and Case Series.

    PubMed

    Vargas-Schaffer, Grisell; Nowakowsky, Michal; Eghtesadi, Marzieh; Cogan, Jennifer

    2015-09-15

    Chronic chest pain is a challenge, and serratus anterior muscle pain syndrome (SAMPS) is often overlooked. We have developed an ultrasound-guided technique for infiltrating local anesthetics and steroids in patients with SAMPS. In 8 patients, the duration of chronic pain was approximately 19 months. Three months after treatment, all patients had experienced a significant reduction in pain. Infiltration for SAMPS confirms the diagnosis and provides adequate pain relief.

  4. Using a Delphi Technique to Seek Consensus Regarding Definitions, Descriptions and Classification of Terms Related to Implicit and Explicit Forms of Motor Learning

    PubMed Central

    Kleynen, Melanie; Braun, Susy M.; Bleijlevens, Michel H.; Lexis, Monique A.; Rasquin, Sascha M.; Halfens, Jos; Wilson, Mark R.; Beurskens, Anna J.; Masters, Rich S. W.

    2014-01-01

    Background Motor learning is central to domains such as sports and rehabilitation; however, often terminologies are insufficiently uniform to allow effective sharing of experience or translation of knowledge. A study using a Delphi technique was conducted to ascertain level of agreement between experts from different motor learning domains (i.e., therapists, coaches, researchers) with respect to definitions and descriptions of a fundamental conceptual distinction within motor learning, namely implicit and explicit motor learning. Methods A Delphi technique was embedded in multiple rounds of a survey designed to collect and aggregate informed opinions of 49 international respondents with expertise related to motor learning. The survey was administered via an online survey program and accompanied by feedback after each round. Consensus was considered to be reached if ≥70% of the experts agreed on a topic. Results Consensus was reached with respect to definitions of implicit and explicit motor learning, and seven common primary intervention strategies were identified in the context of implicit and explicit motor learning. Consensus was not reached with respect to whether the strategies promote implicit or explicit forms of learning. Discussion The definitions and descriptions agreed upon may aid translation and transfer of knowledge between domains in the field of motor learning. Empirical and clinical research is required to confirm the accuracy of the definitions and to explore the feasibility of the strategies that were identified in research, everyday practice and education. PMID:24968228

  5. On the Need for Practical Formal Methods

    DTIC Science & Technology

    1998-01-01

    either a good violin or a highly talented violinist . Light-weight techniques o er software developers good violins. A user need not be a talented... violinist to bene t. This is in contrast to heavy-duty techniques where the user needs to be a good violinist . Formal methods research has already produced a

  6. Innovative techniques for the description of reservoir heterogeneity using tracers. Second technical annual progress report, October 1991--September 1992

    SciTech Connect

    Pope, G.A.; Sepehrnoori, K.

    1992-12-31

    This second annual report on innovative uses of tracers for reservoir characterization contains four sections each describing a novel use of oilfield tracers. The first section describes and illustrates the use of a new single-well tracer test to estimate wettability. This test consists of the injection of brine containing tracers followed by oil containing tracers, a shut-in period to allow some of the tracers to react, and then production of the tracers. The inclusion of the oil injection slug with tracers is unique to this test, and this is what makes the test work. We adapted our chemical simulator, UTCHEM, to enable us to study this tracer method and made an extensive simulation study to evaluate the effects of wettability based upon characteristic curves for relative permeability and capillary pressure for differing wetting states typical of oil reservoirs. The second section of this report describes a new method for analyzing interwell tracer data based upon a type-curve approach. Theoretical frequency response functions were used to build type curves of ``transfer function`` and ``phase spectrum`` that have dimensionless heterogeneity index as a parameter to characterize a stochastic permeability field. We illustrate this method by analyzing field tracer data. The third section of this report describes a new theory for interpreting interwell tracer data in terms of channeling and dispersive behavior for reservoirs. Once again, a stochastic approach to reservoir description is taken. The fourth section of this report describes our simulation of perfluorocarbon gas tracers. This new tracer technology developed at Brookhaven National Laboratory is being tested at the Elk Hills Naval Petroleum Reserve No. 1 in California. We report preliminary simulations made of these tracers in one of the oil reservoirs under evaluation with these tracers in this field. Our compostional simulator (UTCOMP) was used for this simulation study.

  7. A new technique to make transparent teeth without decalcifying: description of the methodology and micro-hardness assessment.

    PubMed

    Malentacca, Augusto; Lajolo, Carlo

    2015-01-01

    Diaphanisation and other in vitro endodontic models (i.e., plastic blocks, micro-CT reconstruction, computerised models) do not recreate real root canal working conditions: a more realistic endodontic model is essential for testing endodontic devices and teaching purposes. The aim of this study was to describe a new technique to construct transparent teeth without decalcifying and evaluate the micro-hardness of so treated teeth. Thirty freshly extracted teeth were randomly divided into three groups as follows: 10 non-treated teeth (4 molars, 3 premolars, 3 incisors; control group - G1), 10 teeth were diaphanised (4 molars, 4 premolars, 2 incisors - G2) and 10 teeth were treated with the new proposed technique (2 molars, 6 premolars, 2 incisors - G3). Vickers hardness tester (MHT-4 and AxioVision microscope, Carl Zeiss, 37030 Gottingen, Germany - load=50 g, dwell time=20s, slope=5, 50× magnification) was used to determine microhardness (Vickers Hardness Number - VHN). Statistical analysis was performed using the Intercooled Stata 8.0 software (Stata Corporation, College Station, TX, USA). Only groups 1 and 3 could be tested for hardness because diaphanised teeth were too tender and elastic. Differences in enamel VHN were observed between G1 (mean 304.29; DS=10.44; range 283-321) and G3 (mean 318.51; DS=14.36; range 295.5-339.2) - (p<0.05); differences in dentine VHN were observed between G1 (mean 74.73; DS=6.62; range 63.9-88.1) and G3 (mean 64.54; DS=5.55; range 51.2-72.3) - (p<0.05). G3 teeth presented a slightly lower VHN compared to G1, probably due to some little structural differences among groups, and were dramatically harder than the diaphanised teeth. The described technique, thus, can be considered ideal for testing endodontic instruments and for teaching purposes.

  8. Apparatus description and data analysis of a radiometric technique for measurements of spectral and total normal emittance

    NASA Technical Reports Server (NTRS)

    Edwards, S. F.; Kantsios, A. G.; Voros, J. P.; Stewart, W. F.

    1975-01-01

    The development of a radiometric technique for determining the spectral and total normal emittance of materials heated to temperatures of 800, 1100, and 1300 K by direct comparison with National Bureau of Standards (NBS) reference specimens is discussed. Emittances are measured over the spectral range of 1 to 15 microns and are statistically compared with NBS reference specimens. Results are included for NBS reference specimens, Rene 41, alundum, zirconia, AISI type 321 stainless steel, nickel 201, and a space-shuttle reusable surface insulation.

  9. Lagrangian-Hamiltonian unified formalism for field theory

    NASA Astrophysics Data System (ADS)

    Echeverría-Enríquez, Arturo; López, Carlos; Marín-Solano, Jesús; Muñoz-Lecanda, Miguel C.; Román-Roy, Narciso

    2004-01-01

    The Rusk-Skinner formalism was developed in order to give a geometrical unified formalism for describing mechanical systems. It incorporates all the characteristics of Lagrangian and Hamiltonian descriptions of these systems (including dynamical equations and solutions, constraints, Legendre map, evolution operators, equivalence, etc.). In this work we extend this unified framework to first-order classical field theories, and show how this description comprises the main features of the Lagrangian and Hamiltonian formalisms, both for the regular and singular cases. This formulation is a first step toward further applications in optimal control theory for partial differential equations.

  10. Retzus-sparing robotic-assisted laparoscopic radical prostatectomy: a step–by-step technique description of this first brazilian experience

    PubMed Central

    Tobias-Machado, Marcos; Nunes-Silva, Igor; Hidaka, Alexandre Kiyoshi; Sato, Leticia Lumy Kanawa; Almeida, Roberto; Colombo, Jose Roberto; Zampolli, Hamilton de Campos; Pompeo, Antonio Carlos Lima

    2016-01-01

    Abstract Introduction: Retzus-sparing robotic-assisted radical prostatectomy(RARP) is a newly approach that preserve the Retzus structures and provide better recovery of continence and erectile function. In Brazil, this approach has not yet been previously reported. Objective: Our goal is to describe Step-by-Step the Retzus-sparing RARP surgical technique and report our first Brazilian experience. Methods: We present a case of a 60-year-old white man with low risk prostate cancer. Surgical materials were four arms Da Vinci robotic platform system, six transperitoneal portals, two prolene wires and Polymer Clips. This surgical technique was step-by-step described according to Galfano et al. One additional step was added as a modification of Galfano et al. Primary technique description: The closure of the Denovellier fascia. Results: We have operated one patient with this technique. The operative time was 180minutes, console time was135 min, the blood loss was 150ml, none perioperative or postoperative complications was found, hospital stay of 01 day. The anatomopathological classification revealed a pT2aN0M0 specimen with free surgical margins. The patient achieved continence immediately after bladder stent retrieval. Full erection reported after 30 days of surgery. Conclusion: Retzus-sparing RARP approach is feasible and reproducible. However, further comparative studies are necessary to demonstrate potential benefits in continence and sexual outcomes over the standard approaches. PMID:27649115

  11. Description and interpretation of the bracts epidermis of Gramineae (Poaceae) with rotated image with maximum average power spectrum (RIMAPS) technique.

    PubMed

    Favret, Eduardo A; Fuentes, Néstor O; Molina, Ana M; Setten, Lorena M

    2008-10-01

    During the last few years, RIMAPS technique has been used to characterize the micro-relief of metallic surfaces and recently also applied to biological surfaces. RIMAPS is an image analysis technique which uses the rotation of an image and calculates its average power spectrum. Here, it is presented as a tool for describing the morphology of the trichodium net found in some grasses, which is developed on the epidermal cells of the lemma. Three different species of grasses (herbarium samples) are analyzed: Podagrostis aequivalvis (Trin.) Scribn. & Merr., Bromidium hygrometricum (Nees) Nees & Meyen and Bromidium ramboi (Parodi) Rúgolo. Simple schemes representing the real microstructure of the lemma are proposed and studied. RIMAPS spectra of both the schemes and the real microstructures are compared. These results allow inferring how similar the proposed geometrical schemes are to the real microstructures. Each geometrical pattern could be used as a reference for classifying other species. Finally, this kind of analysis is used to determine the morphology of the trichodium net of Agrostis breviculmis Hitchc. As the dried sample had shrunk and the microstructure was not clear, two kinds of morphology are proposed for the trichodium net of Agrostis L., one elliptical and the other rectilinear, the former being the most suitable.

  12. HOW CAN BONE TUNNEL ENLARGEMENT IN ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION SURGERY BE MEASURED? DESCRIPTION OF A TECHNIQUE

    PubMed Central

    Aguiar Leonardi, Adriano Barros de; Severino, Nilson Roberto; Junior, Aires Duarte

    2015-01-01

    To assess the presence of tibial bone tunnel enlargement after surgery to reconstruct the anterior cruciate ligament using quadruple flexor tendon grafts, and to propose a new technique for its measurement. Methods: The study involved 25 patients aged 18-43 years over a six-month period. The assessment was based on radiographs taken immediately postoperatively and in the third and sixth months of evolution after operations to reconstruct the anterior cruciate ligament using grafts from the tendons of the semitendinosus and gracilis muscles, fixed in the femur with a transverse metal screw and in the tibia with an interference screw. The radiographs were evaluated in terms of the relative value between the diameter of the tunnel and the bone, both at 2 cm below the medial tibial condyle. Results: There were significant increases in tunnel diameters: 20.56% for radiographs in anteroposterior view and 26.48% in lateral view. Enlargement was present in 48% of anteroposterior and lateral radiographs, but was present in both views in only 16% of the cases. Conclusions: Bone tunnel enlargement is a phenomenon found in the first months after surgery to reconstruct the anterior cruciate ligament. The measurement technique proposed in this study was sufficient to detect it. PMID:27027030

  13. Formal techniques improve connectivity in supervisory systems

    SciTech Connect

    Luque, J.; Perez, F.; Mejias, M. ); Gonzalo, F. )

    1994-04-01

    The need to provide communication among the various computers that make up supervisory control and data acquisition (SCADA) systems is encountered more and more frequently. This equipment is usually from various generations, technologies, and manufacturers. Much effort has been made to define a set of standard protocols for both center-remote communications and to center-to-center links of similar or different levels. Nevertheless, the future role of these standards is not clear, and the problem still remains of how to ensure communication among the systems working presently. As described in this article, Sevillana de Electricidad (the electric utility company covering southern Spain), the University of Seville, and local vendors of control systems have jointly developed a project to solve this problem in a more general manner, through the development of an automatic conversion tool, called CUP. These letters denote the Spanish equivalent of universal protocol conversion (converter). This project has been sponsored by the Spanish Ministry of Industry, through the National Electrical Research Plan.

  14. Perisciatic Ultrasound-Guided Infiltration for Treatment of Deep Gluteal Syndrome: Description of Technique and Preliminary Results.

    PubMed

    Rosales, Julio; García, Nicolás; Rafols, Claudio; Pérez, Marcelo; Verdugo, Marco A

    2015-11-01

    The objective of this study was to describe a perisciatic ultrasound-guided infiltration technique for treatment of deep gluteal syndrome and to report its preliminary clinical results. A mixture of saline (20 mL), a local anesthetic (4 mL), and a corticosteroid solution (1 mL) was infiltrated in the perisciatic region between the gluteus maximus and pelvitrochanteric muscles. Relative pain relief was achieved in 73.7% of the patients, with average preprocedural and postprocedural visual analog scale scores of 8.3 and 2.8, respectively. Fifty percent of patients reported recurrence of discomfort, and the average duration of the therapeutic effect in these patients was 5.3 weeks.

  15. Novel techniques for biodiversity studies of gordiids and description of a new species of Chordodes (Gordiida, Nematomorpha) from Kenya, Africa.

    PubMed

    Bolek, Matthew G; Szmygiel, Cleo; Kubat, Austin; Schmidt-Rhaesa, Andreas; Hanelt, Ben

    2013-01-01

    We review recent advances in the use of non-adult gordiid cyst stages to locate gordiids over large geographical regions and new culturing techniques which can help overcome current difficulties in nematomorph biodiversity studies. Using these techniques, we collected a new species of gordiid as cysts in aquatic snails (Biomphalaria pfeifferi) from the Lake Victoria Basin, western Kenya, Africa and cultured them in the laboratory. We describe the adult free-living male and female worms using morphological (light and scanning electron microscopy) and molecular data as well as the life cycle, mating and oviposition behavior, egg strings, eggs, larvae, and cysts of this new species. Chordodes kenyaensis n. sp. belongs to a large group of African Chordodes in which simple areoles are smooth or superficially structured less so than "blackberry" areoles but contain filamentous projections. Present among the simple areoles are clusters of bulging areoles, crowned and circurmcluster areoles along with thorn and tubercle areoles. In the laboratory, worms developed and emerged within 53-78 days from three, species of laboratory-reared crickets exposed to cysts of this species. Adult male and female C. kenyaensis n. sp. initiated typical Gordian knots within hours to days of being placed together and males deposited masses of sperm on the cloacal region of females. Females began oviposition within a week of copulating and attached egg strings in a continuous zigzag pattern on small branches or air-hoses but never free in the water column. Larvae hatched within two to three weeks, and cysts developed in laboratory-reared and exposed snails within 14-24 days. Morphological characteristics of egg strings, eggs, larvae and cysts of C. kenyaensis were most similar to other gordiids in the genus Chordodes but differed morphologically from other gordiid genera for which similar information is available.

  16. Quantification of rainfall prediction uncertainties using a cross-validation based technique. Methodology description and experimental validation.

    NASA Astrophysics Data System (ADS)

    Fraga, Ignacio; Cea, Luis; Puertas, Jerónimo; Salsón, Santiago; Petazzi, Alberto

    2016-04-01

    In this paper we present a new methodology to compute rainfall fields including the quantification of predictions uncertainties using raingauge network data. The proposed methodology comprises two steps. Firstly, the ordinary krigging technique is used to determine the estimated rainfall depth in every point of the study area. Then multiple equi-probable errors fields, which comprise both interpolation and measuring uncertainties, are added to the krigged field resulting in multiple rainfall predictions. To compute these error fields first the standard deviation of the krigging estimation is determined following the cross-validation based procedure described in Delrieu et al. (2014). Then, the standard deviation field is sampled using non-conditioned Gaussian random fields. The proposed methodology was applied to study 7 rain events in a 60x60 km area of the west coast of Galicia, in the Northwest of Spain. Due to its location at the junction between tropical and polar regions, the study area suffers from frequent intense rainfalls characterized by a great variability in terms of both space and time. Rainfall data from the tipping bucket raingauge network operated by MeteoGalicia were used to estimate the rainfall fields using the proposed methodology. The obtained predictions were then validated using rainfall data from 3 additional rain gauges installed within the CAPRI project (Probabilistic flood prediction with high resolution hydrologic models from radar rainfall estimates, funded by the Spanish Ministry of Economy and Competitiveness. Reference CGL2013-46245-R.). Results show that both the mean hyetographs and the peak intensities are correctly predicted. The computed hyetographs present a good fit to the experimental data and most of the measured values fall within the 95% confidence intervals. Also, most of the experimental values outside the confidence bounds correspond to time periods of low rainfall depths, where the inaccuracy of the measuring devices

  17. Posterior lumbar dynamic stabilization instead of arthrodesis for symptomatic adjacent-segment degenerative stenosis: description of a novel technique.

    PubMed

    Mashaly, Hazem; Paschel, Erin E; Khattar, Nicolas K; Goldschmidt, Ezequiel; Gerszten, Peter C

    2016-01-01

    OBJECTIVE The development of symptomatic adjacent-segment disease (ASD) is a well-recognized consequence of lumbar fusion surgery. Extension of a fusion to a diseased segment may only lead to subsequent adjacent-segment degeneration. The authors report the use of a novel technique that uses dynamic stabilization instead of arthrodesis for the surgical treatment of symptomatic ASD following a prior lumbar instrumented fusion. METHODS A cohort of 28 consecutive patients was evaluated who developed symptomatic stenosis immediately adjacent to a previous lumbar instrumented fusion. All patients had symptoms of neurogenic claudication refractory to nonsurgical treatment and were surgically treated with decompression and dynamic stabilization instead of extending the fusion construct using a posterior lumbar dynamic stabilization system. Preoperative symptoms, visual analog scale (VAS) pain scores, and perioperative complications were recorded. Clinical outcome was gauged by comparing VAS scores prior to surgery and at the time of last follow-up. RESULTS The mean follow-up duration was 52 months (range 17-94 months). The mean interval from the time of primary fusion surgery to the dynamic stabilization surgery was 40 months (range 10-96 months). The mean patient age was 51 years (range 29-76 years). There were 19 (68%) men and 9 (32%) women. Twenty-three patients (82%) presented with low-back pain at time of surgery, whereas 24 patients (86%) presented with lower-extremity symptoms only. Twenty-four patients (86%) underwent operations that were performed using single-level dynamic stabilization, 3 patients (11%) were treated at 2 levels, and 1 patient underwent 3-level decompression and dynamic stabilization. The most commonly affected and treated level (46%) was L3-4. The mean preoperative VAS pain score was 8, whereas the mean postoperative score was 3. No patient required surgery for symptomatic degeneration rostral to the level of dynamic stabilization during the

  18. Intravascular ultrasound guidance of percutaneous coronary intervention in ostial chronic total occlusions: a description of the technique and procedural results.

    PubMed

    Ryan, Nicola; Gonzalo, Nieves; Dingli, Philip; Cruz, Oscar Vedia; Jiménez-Quevedo, Pilar; Nombela-Franco, Luis; Nuñez-Gil, Ivan; Trigo, María Del; Salinas, Pablo; Macaya, Carlos; Fernandez-Ortiz, Antonio; Escaned, Javier

    2017-02-14

    Inability to cross the lesion with a guidewire is the most common reason for failure in percutaneous revascularization (PCI) of chronic total occlusions (CTOs). An ostial or stumpless CTO is an acknowledged challenge for CTO recanalization due to difficulty in successful wiring. IVUS imaging provides the opportunity to visualize the occluded vessel and to aid guidewire advancement. We review the value of this technique in a single-centre experience of CTO PCI. This series involves 22 patients who underwent CTO-PCI using IVUS guidance for stumpless CTO wiring at our institution. CTO operators with extensive IVUS experience in non-CTO cases carried out all procedures. Procedural and outcome data was prospectively entered into the institutional database and a retrospective analysis of clinical, angiographic and technical data performed. 17 (77%) of the 22 procedures were successful. The mean age was 59.8 ± 11.5 years, and 90.9% were male. The most commonly attempted lesions were located in the left anterior descending 36.4% (Soon et al. in J Intervent Cardiol 20(5):359-366, 2007) and Circumflex artery (LCx) 31.8% (Mollet et al. in Am J Cardiol 95(2):240-243, 2005). Mean JCTO score was 3.09 ± 0.75 (3.06 ± 0.68, 3.17 ± 0.98 in the successful and failed groups respectively p = 0.35). The mean contrast volume was 378.7 ml ± 114.7 (389.9 ml ± 130.5, 349.2 ml ± 52.2 p = 0.3 in the successful and failed groups respectively). There was no death, coronary artery bypass grafting or myocardial infarction requiring intervention in this series. When the success rates were analyzed taking into account the date of adoption of this technique, the learning curve had no significant impact on CTO-PCI success. This series describes a good success rate in IVUS guided stumpless wiring of CTOs in consecutive patients with this complex anatomical scenario.

  19. Software Formal Inspections Standard

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This Software Formal Inspections Standard (hereinafter referred to as Standard) is applicable to NASA software. This Standard defines the requirements that shall be fulfilled by the software formal inspections process whenever this process is specified for NASA software. The objective of this Standard is to define the requirements for a process that inspects software products to detect and eliminate defects as early as possible in the software life cycle. The process also provides for the collection and analysis of inspection data to improve the inspection process as well as the quality of the software.

  20. A non-commuting stabilizer formalism

    SciTech Connect

    Ni, Xiaotong; Van den Nest, Maarten; Buerschaper, Oliver

    2015-05-15

    We propose a non-commutative extension of the Pauli stabilizer formalism. The aim is to describe a class of many-body quantum states which is richer than the standard Pauli stabilizer states. In our framework, stabilizer operators are tensor products of single-qubit operators drawn from the group 〈αI, X, S〉, where α = e{sup iπ/4} and S = diag(1, i). We provide techniques to efficiently compute various properties related to bipartite entanglement, expectation values of local observables, preparation by means of quantum circuits, parent Hamiltonians, etc. We also highlight significant differences compared to the Pauli stabilizer formalism. In particular, we give examples of states in our formalism which cannot arise in the Pauli stabilizer formalism, such as topological models that support non-Abelian anyons.

  1. Correlates of Formal Reasoning.

    ERIC Educational Resources Information Center

    Linn, Marcia C.; Pulos, Steven

    This study of Piagetian formal reasoning in seventh grade students reports the relationships between four aspects of the ability to control variables in an experiment and the relationships between those four aspects and other constructs. The four aspects of the ability to control variables identified are: (1) set up a controlled experiment, (2)…

  2. Formal analysis of electromagnetic optics

    NASA Astrophysics Data System (ADS)

    Khan-Afshar, Sanaz; Hasan, Osman; Tahar, Sofiène

    2014-09-01

    Optical systems are increasingly being used in safety-critical applications. Due to the complexity and sensitivity of optical systems, their verification raises many challenges for engineers. Traditionally, the analysis of such systems has been carried out by paper-and-pencil based proofs and numerical computations. However, these techniques cannot provide accurate results due to the risk of human error and inherent approximations of numerical algorithms. In order to overcome these limitations, we propose to use theorem proving (i.e., a computer-based technique that allows to express mathematical expressions and reason about their correctness by taking into account all the details of mathematical reasoning) as a complementary approach to improve optical system analysis. This paper provides a higher-order logic (a language used to express mathematical theories) formalization of electromagnetic optics in the HOL Light theorem prover. In order to demonstrate the practical effectiveness of our approach, we present the analysis of resonant cavity enhanced photonic devices.

  3. Link-space formalism for network analysis.

    PubMed

    Smith, David M D; Lee, Chiu Fan; Onnela, Jukka-Pekka; Johnson, Neil F

    2008-03-01

    We introduce the link-space formalism for analyzing network models with degree-degree correlations. The formalism is based on a statistical description of the fraction of links l(i,j) connecting nodes of degrees i and j. To demonstrate its use, we apply the framework to some pedagogical network models, namely, random attachment, Barabási-Albert preferential attachment, and the classical Erdos and Rényi random graph. For these three models the link-space matrix can be solved analytically. We apply the formalism to a simple one-parameter growing network model whose numerical solution exemplifies the effect of degree-degree correlations for the resulting degree distribution. We also employ the formalism to derive the degree distributions of two very simple network decay models, more specifically, that of random link deletion and random node deletion. The formalism allows detailed analysis of the correlations within networks and we also employ it to derive the form of a perfectly nonassortative network for arbitrary degree distribution.

  4. Semisymmetric systems: Hermitian formalism

    NASA Astrophysics Data System (ADS)

    Buchdahl, H. A.

    1995-04-01

    The power series representing the characteristic function of a regular semisymmetric system involves four linearly independent rotational invariants XA (A=1,.. .,4) that jointly satisfy a quadratic identity. When the X A are appropriately chosen, this takes the form -(X1)2-(X2 )2-(X3)2+( X4)2=0 . The XA are thus the components of a null vector in a four-dimensional Euclidean space whose metric is gAB: =diag(-1,-1 ,-1,1) . Such a vector is equivalent to a simple 2-spinor xi alpha . The intrinsic presence of a spin vector in the formalism used hitherto suggests that it might be of advantage to replace the latter with an explicit 2-spinor formalism. A way of doing this is examined.

  5. Formality of the Chinese collective leadership.

    PubMed

    Li, Haiying; Graesser, Arthur C

    2016-09-01

    We investigated the linguistic patterns in the discourse of four generations of the collective leadership of the Communist Party of China (CPC) from 1921 to 2012. The texts of Mao Zedong, Deng Xiaoping, Jiang Zemin, and Hu Jintao were analyzed using computational linguistic techniques (a Chinese formality score) to explore the persuasive linguistic features of the leaders in the contexts of power phase, the nation's education level, power duration, and age. The study was guided by the elaboration likelihood model of persuasion, which includes a central route (represented by formal discourse) versus a peripheral route (represented by informal discourse) to persuasion. The results revealed that these leaders adopted the formal, central route more when they were in power than before they came into power. The nation's education level was a significant factor in the leaders' adoption of the persuasion strategy. The leaders' formality also decreased with their increasing age and in-power times. However, the predictability of these factors for formality had subtle differences among the different types of leaders. These results enhance our understanding of the Chinese collective leadership and the role of formality in politically persuasive messages.

  6. Formal verification of an avionics microprocessor

    NASA Technical Reports Server (NTRS)

    Srivas, Mandayam, K.; Miller, Steven P.

    1995-01-01

    Formal specification combined with mechanical verification is a promising approach for achieving the extremely high levels of assurance required of safety-critical digital systems. However, many questions remain regarding their use in practice: Can these techniques scale up to industrial systems, where are they likely to be useful, and how should industry go about incorporating them into practice? This report discusses a project undertaken to answer some of these questions, the formal verification of the AAMPS microprocessor. This project consisted of formally specifying in the PVS language a rockwell proprietary microprocessor at both the instruction-set and register-transfer levels and using the PVS theorem prover to show that the microcode correctly implemented the instruction-level specification for a representative subset of instructions. Notable aspects of this project include the use of a formal specification language by practicing hardware and software engineers, the integration of traditional inspections with formal specifications, and the use of a mechanical theorem prover to verify a portion of a commercial, pipelined microprocessor that was not explicitly designed for formal verification.

  7. Formal Methods for Privacy

    DTIC Science & Technology

    2009-09-01

    Against a vast and rich canvas of diverse types of privacy rights and violations, we argue technology’s dual role in privacy : new technologies raise...new threats to privacy rights and new technologies can help preserve privacy . Formal methods, as just one class of technology , can be applied to...differs from what a teenager thinks, and vice versa [18]. New technologies give rise to new privacy concerns. Warren and Brandeis’s 1890 seminal paper

  8. Formal concept analysis and linguistic hedges

    NASA Astrophysics Data System (ADS)

    Belohlavek, Radim; Vychodil, Vilem

    2012-07-01

    This paper presents an application of linguistic hedges to formal concept analysis of data with fuzzy attributes. Formal concept analysis aims at extraction of particular (bi-)clusters, called formal concepts, from data. The clusters link collections of objects (extents) and attributes (intents), and have a clear interpretation due to a simple verbal description of the concept-forming operators. We insert linguistic hedges such as 'very' or 'extremely' in the description of the operators. In this way, linguistic hedges become parameters for formal concept analysis that control the number of clusters extracted from data. Namely, as we show theoretically as well as experimentally, stronger hedges result in a smaller number of clusters. The new concept-forming operators form Galois-like connections. We study their properties and axiomatize them. Then, we show that a concept lattice with hedges, i.e. the set of all formal concepts of the new operators is indeed a complete lattice which is isomorphic to a particular ordinary concept lattice. We describe the isomorphism and its inverse. These mappings serve as translation procedures. As a consequence, we obtain a theorem characterizing the structure of concept lattices with hedges which generalizes the well-known main theorem of ordinary concept lattices. The isomorphism and its inverse enable us to compute a concept lattice with hedges using algorithms for ordinary concept lattices. We demonstrate by experiments that when selecting various hedges from the strongest to weaker hedges, the reduction in size of the corresponding concept lattices is smooth. From a broader perspective, we argue that linguistic hedges represent mathematically and computationally a feasible way to parameterize methods for knowledge extraction from data that enable one to emphasize or to suppress extracted patterns while keeping their interpretation.

  9. Formal caregivers of older adults: reflection about their practice

    PubMed Central

    Batista, Marina Picazzio Perez; Barros, Juliana de Oliveira; de Almeida, Maria Helena Morgani; Mângia, Elisabete Ferreira; Lancman, Selma

    2014-01-01

    OBJECTIVE To understand the job function of caregivers of older adults and contribute to the debate on the consolidation of this professional practice. METHODOLOGICAL PROCEDURES This is a descriptive, qualitative, and exploratory study. Four focal group sessions were performed in 2011 with 11 elderly companions, formal caregivers of older adults in the Programa Acompanhante de Idosos (Program for Caregivers of Older Adults), Sao Paulo, SP, Southeastern Brazil. These sessions, guided by a semi-structured script, were audio-recorded and fully transcribed. Data were analyzed using the Content Analysis technique, Thematic Modality. RESULTS In view of considering the caregivers of older adults as a new category of workers, it was difficult to define their duties. The elderly companions themselves as well as the care receivers, their families, and the professionals that comprised the team were unclear about their duties. The professional practice of these formal caregivers has been built on the basis of constant discussions and negotiations among them and other team members in Programa Acompanhante de Idosos during daily work. This was achieved via a recognition process of their job functions and by setting apart other workers’ exclusive responsibilities. CONCLUSIONS The delimitation of specific job functions for elderly companions is currently one of the greatest challenges faced by these workers to develop and consolidate their professional role as well as improve Programa Acompanhante de Idosos. PMID:25372163

  10. Identifying Concrete and Formal Operational Children.

    ERIC Educational Resources Information Center

    Docherty, Edward M.

    This paper presents a study designed to determine if groups of concrete and formal operational children can be identified through the technique of cluster analysis, using a battery of Piagetian tasks. A Total of 64 subjects, 8 boys and 8 girls from each of the second, fourth, sixth, and eighth grade levels, were selected from a public elementary…

  11. Formalizing the concept of sound.

    SciTech Connect

    Kaper, H. G.; Tipei, S.

    1999-08-03

    The notion of formalized music implies that a musical composition can be described in mathematical terms. In this article we explore some formal aspects of music and propose a framework for an abstract approach.

  12. Covariant Bardeen perturbation formalism

    NASA Astrophysics Data System (ADS)

    Vitenti, S. D. P.; Falciano, F. T.; Pinto-Neto, N.

    2014-05-01

    In a previous work we obtained a set of necessary conditions for the linear approximation in cosmology. Here we discuss the relations of this approach with the so-called covariant perturbations. It is often argued in the literature that one of the main advantages of the covariant approach to describe cosmological perturbations is that the Bardeen formalism is coordinate dependent. In this paper we will reformulate the Bardeen approach in a completely covariant manner. For that, we introduce the notion of pure and mixed tensors, which yields an adequate language to treat both perturbative approaches in a common framework. We then stress that in the referred covariant approach, one necessarily introduces an additional hypersurface choice to the problem. Using our mixed and pure tensors approach, we are able to construct a one-to-one map relating the usual gauge dependence of the Bardeen formalism with the hypersurface dependence inherent to the covariant approach. Finally, through the use of this map, we define full nonlinear tensors that at first order correspond to the three known gauge invariant variables Φ, Ψ and Ξ, which are simultaneously foliation and gauge invariant. We then stress that the use of the proposed mixed tensors allows one to construct simultaneously gauge and hypersurface invariant variables at any order.

  13. IDEF5 Ontology Description Capture Method: Concepts and Formal Foundations

    DTIC Science & Technology

    1992-11-01

    Based Sysstems Laboratory of the Department of Industrial Engineering at Texas A&M t’nIversttv Funding for the Laboratory’s research in Integrated...Mayer KNOWLEDGE BASED SYSTEMS LABORATORY L DEPARTMENT OF INDUSTRIAL ENGINEERING TEXAS A&M UNIVERSITY B COLLEGE STATION. TX 77843 Michael K. Painter. Capt...PERFORMING ORGANIZATION NAME(S) AND AOODRSSjES) 6 PI tRtt$N•G OAGAINVI.WfN Knowledge Based Systems Laboratory Department of Industrial Engineering Texas A&M

  14. A Formal Basis for Safety Case Patterns

    NASA Technical Reports Server (NTRS)

    Denney, Ewen; Pai, Ganesh

    2013-01-01

    By capturing common structures of successful arguments, safety case patterns provide an approach for reusing strategies for reasoning about safety. In the current state of the practice, patterns exist as descriptive specifications with informal semantics, which not only offer little opportunity for more sophisticated usage such as automated instantiation, composition and manipulation, but also impede standardization efforts and tool interoperability. To address these concerns, this paper gives (i) a formal definition for safety case patterns, clarifying both restrictions on the usage of multiplicity and well-founded recursion in structural abstraction, (ii) formal semantics to patterns, and (iii) a generic data model and algorithm for pattern instantiation. We illustrate our contributions by application to a new pattern, the requirements breakdown pattern, which builds upon our previous work

  15. IDEF3 formalization report

    NASA Technical Reports Server (NTRS)

    Menzel, Christopher; Mayer, Richard J.; Edwards, Douglas D.

    1991-01-01

    The Process Description Capture Method (IDEF3) is one of several Integrated Computer-Aided Manufacturing (ICAM) DEFinition methods developed by the Air Force to support systems engineering activities, and in particular, to support information systems development. These methods have evolved as a distillation of 'good practice' experience by information system developers and are designed to raise the performance level of the novice practitioner to one comparable with that of an expert. IDEF3 is meant to serve as a knowledge acquisition and requirements definition tool that structures the user's understanding of how a given process, event, or system works around process descriptions. A special purpose graphical language accompanying the method serves to highlight temporal precedence and causality relationships relative to the process or event being described.

  16. IDEF3 Formalization Report

    DTIC Science & Technology

    1991-10-01

    CLASSIFICATION 19. SECURITY CLASSIFICATION 20. LIMITATION OF ABSTRACT OF REPORT OF THIS PAGE OF ABSTRACT L Unclassified Unclassified Unclassified IUL x ...might be described. IDEF3 aims at producing high-level, general- purpose descriptions of processes. These are IDEFS models, not to be con- fused with...lower case letters x , y, and z, possibly with subscripts, will play this role, and we will suppose there to be an unlimited store of them. We will use the

  17. New Technologies and Learning Environments: A Perspective from Formal and Non-Formal Education in Baja California, Mexico

    ERIC Educational Resources Information Center

    Zamora, Julieta Lopez; Reynaga, Francisco Javier Arriaga

    2010-01-01

    This paper presents results of two research works, the first approaches non-formal education and the second addresses formal education. In both studies in-depth interview techniques were used. There were some points of convergence between them on aspects such as the implementation of learning environments and the integration of ICT. The interview…

  18. Formalized Epistemology, Logic, and Grammar

    NASA Astrophysics Data System (ADS)

    Bitbol, Michel

    The task of a formal epistemology is defined. It appears that a formal epistemology must be a generalization of "logic" in the sense of Wittgenstein's Tractatus. The generalization is required because, whereas logic presupposes a strict relation between activity and language, this relation may be broken in some domains of experimental enquiry (e.g., in microscopic physics). However, a formal epistemology should also retain a major feature of Wittgenstein's "logic": It must not be a discourse about scientific knowledge, but rather a way of making manifest the structures usually implicit in knowledge-gaining activity. This strategy is applied to the formalism of quantum mechanics.

  19. Incremental and unifying modelling formalism for biological interaction networks

    PubMed Central

    Yartseva, Anastasia; Klaudel, Hanna; Devillers, Raymond; Képès, François

    2007-01-01

    Background An appropriate choice of the modeling formalism from the broad range of existing ones may be crucial for efficiently describing and analyzing biological systems. Results We propose a new unifying and incremental formalism for the representation and modeling of biological interaction networks. This formalism allows automated translations into other formalisms, thus enabling a thorough study of the dynamic properties of a biological system. As a first illustration, we propose a translation into the R. Thomas' multivalued logical formalism which provides a possible semantics; a methodology for constructing such models is presented on a classical benchmark: the λ phage genetic switch. We also show how to extract from our model a classical ODE description of the dynamics of a system. Conclusion This approach provides an additional level of description between the biological and mathematical ones. It yields, on the one hand, a knowledge expression in a form which is intuitive for biologists and, on the other hand, its representation in a formal and structured way. PMID:17996051

  20. Formal, Non-Formal and Informal Learning in the Sciences

    ERIC Educational Resources Information Center

    Ainsworth, Heather L.; Eaton, Sarah Elaine

    2010-01-01

    This research report investigates the links between formal, non-formal and informal learning and the differences between them. In particular, the report aims to link these notions of learning to the field of sciences and engineering in Canada and the United States, including professional development of adults working in these fields. It offers…

  1. Toward a Formal Evaluation of Refactorings

    NASA Technical Reports Server (NTRS)

    Paul, John; Kuzmina, Nadya; Gamboa, Ruben; Caldwell, James

    2008-01-01

    Refactoring is a software development strategy that characteristically alters the syntactic structure of a program without changing its external behavior [2]. In this talk we present a methodology for extracting formal models from programs in order to evaluate how incremental refactorings affect the verifiability of their structural specifications. We envision that this same technique may be applicable to other types of properties such as those that concern the design and maintenance of safety-critical systems.

  2. Hardware description languages

    NASA Technical Reports Server (NTRS)

    Tucker, Jerry H.

    1994-01-01

    Hardware description languages are special purpose programming languages. They are primarily used to specify the behavior of digital systems and are rapidly replacing traditional digital system design techniques. This is because they allow the designer to concentrate on how the system should operate rather than on implementation details. Hardware description languages allow a digital system to be described with a wide range of abstraction, and they support top down design techniques. A key feature of any hardware description language environment is its ability to simulate the modeled system. The two most important hardware description languages are Verilog and VHDL. Verilog has been the dominant language for the design of application specific integrated circuits (ASIC's). However, VHDL is rapidly gaining in popularity.

  3. Mending the Gap, An Effort to Aid the Transfer of Formal Methods Technology

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly

    2009-01-01

    Formal methods can be applied to many of the development and verification activities required for civil avionics software. RTCA/DO-178B, Software Considerations in Airborne Systems and Equipment Certification, gives a brief description of using formal methods as an alternate method of compliance with the objectives of that standard. Despite this, the avionics industry at large has been hesitant to adopt formal methods, with few developers have actually used formal methods for certification credit. Why is this so, given the volume of evidence of the benefits of formal methods? This presentation will explore some of the challenges to using formal methods in a certification context and describe the effort by the Formal Methods Subgroup of RTCA SC-205/EUROCAE WG-71 to develop guidance to make the use of formal methods a recognized approach.

  4. DNA quadruplex folding formalism--a tutorial on quadruplex topologies.

    PubMed

    Karsisiotis, Andreas Ioannis; O'Kane, Christopher; Webba da Silva, Mateus

    2013-11-01

    Quadruplexes of DNA adopt a large variety of topologies that are dependent on their environment. We have been developing a formalism for quadruplex folding based on the relationship between base and its sugar--as defined by the glycosidic bond angle. By reducing the quadruplex stem to a description based on two finite states of the range of angles the glycosidic bond angle may adopt, the description of the relationships of type of loop and groove widths of a quadruplex stem are possible. In its current form this formalism has allowed for the prediction of some unimolecular quadruplex topologies. Its rules, whilst developed for unimolecular quadruplexes of three loops, are of general utility in understanding the interdependency of structural characteristics of multimolecular folds, as well as unimolecular quadruplexes of more than three loops. Here we describe current understanding of the interdependent structural features that define the quadruplex fold, and provide a tutorial for the use and application of this formalism.

  5. Extension of Liouville Formalism to Postinstability Dynamics

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2003-01-01

    A mathematical formalism has been developed for predicting the postinstability motions of a dynamic system governed by a system of nonlinear equations and subject to initial conditions. Previously, there was no general method for prediction and mathematical modeling of postinstability behaviors (e.g., chaos and turbulence) in such a system. The formalism of nonlinear dynamics does not afford means to discriminate between stable and unstable motions: an additional stability analysis is necessary for such discrimination. However, an additional stability analysis does not suggest any modifications of a mathematical model that would enable the model to describe postinstability motions efficiently. The most important type of instability that necessitates a postinstability description is associated with positive Lyapunov exponents. Such an instability leads to exponential growth of small errors in initial conditions or, equivalently, exponential divergence of neighboring trajectories. The development of the present formalism was undertaken in an effort to remove positive Lyapunov exponents. The means chosen to accomplish this is coupling of the governing dynamical equations with the corresponding Liouville equation that describes the evolution of the flow of error probability. The underlying idea is to suppress the divergences of different trajectories that correspond to different initial conditions, without affecting a target trajectory, which is one that starts with prescribed initial conditions.

  6. Formal Foundations for Hierarchical Safety Cases

    NASA Technical Reports Server (NTRS)

    Denney, Ewen; Pai, Ganesh; Whiteside, Iain

    2015-01-01

    Safety cases are increasingly being required in many safety-critical domains to assure, using structured argumentation and evidence, that a system is acceptably safe. However, comprehensive system-wide safety arguments present appreciable challenges to develop, understand, evaluate, and manage, partly due to the volume of information that they aggregate, such as the results of hazard analysis, requirements analysis, testing, formal verification, and other engineering activities. Previously, we have proposed hierarchical safety cases, hicases, to aid the comprehension of safety case argument structures. In this paper, we build on a formal notion of safety case to formalise the use of hierarchy as a structuring technique, and show that hicases satisfy several desirable properties. Our aim is to provide a formal, theoretical foundation for safety cases. In particular, we believe that tools for high assurance systems should be granted similar assurance to the systems to which they are applied. To this end, we formally specify and prove the correctness of key operations for constructing and managing hicases, which gives the specification for implementing hicases in AdvoCATE, our toolset for safety case automation. We motivate and explain the theory with the help of a simple running example, extracted from a real safety case and developed using AdvoCATE.

  7. Unambiguous formalism for higher order Lagrangian field theories

    NASA Astrophysics Data System (ADS)

    Campos, Cédric M.; de León, Manuel; Martín de Diego, David; Vankerschaver, Joris

    2009-11-01

    The aim of this paper is to propose an unambiguous intrinsic formalism for higher order field theories which avoids the arbitrariness in the generalization of the conventional description of field theories, and implies the existence of different Cartan forms and Legendre transformations. We propose a differential-geometric setting for the dynamics of a higher order field theory, based on the Skinner and Rusk formalism for mechanics. This approach incorporates aspects of both the Lagrangian and the Hamiltonian description, since the field equations are formulated using the Lagrangian on a higher order jet bundle and the canonical multisymplectic form on its affine dual. As both of these objects are uniquely defined, the Skinner-Rusk approach has the advantage that it does not suffer from the arbitrariness in conventional descriptions. The result is that we obtain a unique and global intrinsic version of the Euler-Lagrange equations for higher order field theories. Several examples illustrate our construction.

  8. Descriptive statistics.

    PubMed

    Shi, Runhua; McLarty, Jerry W

    2009-10-01

    In this article, we introduced basic concepts of statistics, type of distributions, and descriptive statistics. A few examples were also provided. The basic concepts presented herein are only a fraction of the concepts related to descriptive statistics. Also, there are many commonly used distributions not presented herein, such as Poisson distributions for rare events and exponential distributions, F distributions, and logistic distributions. More information can be found in many statistics books and publications.

  9. Analyzing phonetic confusions using formal concept analysis.

    PubMed

    Peláez-Moreno, C; García-Moral, A I; Valverde-Albacete, F J

    2010-09-01

    Confusion matrices have been used as a tool for the analysis of speech perception or human speech recognition (HSR) for decades. However, they are rarely employed in automatic speech recognition (ASR) mainly due to the lack of a systematic procedure for their exploration. The generalization of formal concept analysis employed in this paper provides a conceptual interpretation of confusion matrices that enables the analysis of the structure of confusions for both human and machine performances. Generalized formal concept analysis transforms confusion matrices into ordered lattices of confusion events, supporting classic results in HSR that identify a hierarchy of virtual articulatory-acoustic channels. Translating this technique into ASR, a detailed map of the relationships among the speech units employed in the system can be traced to make different sources of confusions apparent: the influence of the lexicon, segmentation errors, dialectal variations or limitations of the feature extraction procedures, among others.

  10. Formal Specification of the OpenMP Memory Model

    SciTech Connect

    Bronevetsky, G; de Supinski, B

    2006-12-19

    OpenMP [2] is an important API for shared memory programming, combining shared memory's potential for performance with a simple programming interface. Unfortunately, OpenMP lacks a critical tool for demonstrating whether programs are correct: a formal memory model. Instead, the current official definition of the OpenMP memory model (the OpenMP 2.5 specification [2]) is in terms of informal prose. As a result, it is impossible to verify OpenMP applications formally since the prose does not provide a formal consistency model that precisely describes how reads and writes on different threads interact. We expand on our previous work that focused on the formal verification of OpenMP programs through a formal memory model [?]. As in that work, our formalization, which is derived from the existing prose model [2], provides a two-step process to verify whether an observed OpenMP execution is conformant. This paper extends the model to cover the entire specification. In addition to this formalization, our contributions include a discussion of ambiguities in the current prose-based memory model description. Although our formal model may not capture the current informal memory model perfectly, in part due to these ambiguities, our model reflects our understanding of the informal model's intent. We conclude with several examples that may indicate areas of the OpenMP memory model that need further refinement, however it is specified. Our goal is to motivate the OpenMP community to adopt those refinements eventually, ideally through a formal model, in later OpenMP specifications.

  11. NASA Formal Methods Workshop, 1990

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W. (Compiler)

    1990-01-01

    The workshop brought together researchers involved in the NASA formal methods research effort for detailed technical interchange and provided a mechanism for interaction with representatives from the FAA and the aerospace industry. The workshop also included speakers from industry to debrief the formal methods researchers on the current state of practice in flight critical system design, verification, and certification. The goals were: define and characterize the verification problem for ultra-reliable life critical flight control systems and the current state of practice in industry today; determine the proper role of formal methods in addressing these problems, and assess the state of the art and recent progress toward applying formal methods to this area.

  12. Formalism and functionalism in linguistics.

    PubMed

    Newmeyer, Frederick J

    2010-05-01

    Formalism and functionalism in linguistics are often taken to be diametrically opposed approaches. However, close examination of the relevant phenomena reveals that the two are complementary, rather than being irrevocably in opposition to each other. One can be a formal linguist and a functional linguist at the same time, without there being any contradiction. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.

  13. Statistical foundation of the fluid analogue of the soliton formalism

    NASA Technical Reports Server (NTRS)

    Tchen, C. M.

    1986-01-01

    A fully nonlinear analysis is used to develop a general soliton formalism for the description of the nonlinear evolution of soliton fluctuations in both plasmas and classical fluids. From the Navier-Stokes equations for plasmas and compressible fluids of two scales, two equations for the propagation of density waves are derived. A fast soliton field is spontaneously created by rarefaction, and a slow density wave modulates the field intensity as a ponderomotive force. Constitutive properties are demonstrated using a Lagrangian-kinetic formalism of the fluctuation-dissipation theory.

  14. Management control system description

    SciTech Connect

    Bence, P. J.

    1990-10-01

    This Management Control System (MCS) description describes the processes used to manage the cost and schedule of work performed by Westinghouse Hanford Company (Westinghouse Hanford) for the US Department of Energy, Richland Operations Office (DOE-RL), Richland, Washington. Westinghouse Hanford will maintain and use formal cost and schedule management control systems, as presented in this document, in performing work for the DOE-RL. This MCS description is a controlled document and will be modified or updated as required. This document must be approved by the DOE-RL; thereafter, any significant change will require DOE-RL concurrence. Westinghouse Hanford is the DOE-RL operations and engineering contractor at the Hanford Site. Activities associated with this contract (DE-AC06-87RL10930) include operating existing plant facilities, managing defined projects and programs, and planning future enhancements. This document is designed to comply with Section I-13 of the contract by providing a description of Westinghouse Hanford's cost and schedule control systems used in managing the above activities. 5 refs., 22 figs., 1 tab.

  15. Formalization of an environmental model using formal concept analysis - FCA

    NASA Astrophysics Data System (ADS)

    Bourdon-García, Rubén D.; Burgos-Salcedo, Javier D.

    2016-08-01

    Nowadays, there is a huge necessity to generate novel strategies for social-ecological systems analyses for resolving global sustainability problems. This paper has as main purpose the application of the formal concept analysis to formalize the theory of Augusto Ángel Maya, who without a doubt, was one of the most important environmental philosophers in South America; Ángel Maya proposed and established that Ecosystem-Culture relations, instead Human-Nature ones, are determinants in our understanding and management of natural resources. Based on this, a concept lattice, formal concepts, subconcept-superconcept relations, partially ordered sets, supremum and infimum of the lattice and implications between attributes (Duquenne-Guigues base), were determined for the ecosystem-culture relations.

  16. Formal specification and verification of Ada software

    NASA Technical Reports Server (NTRS)

    Hird, Geoffrey R.

    1991-01-01

    The use of formal methods in software development achieves levels of quality assurance unobtainable by other means. The Larch approach to specification is described, and the specification of avionics software designed to implement the logic of a flight control system is given as an example. Penelope is described which is an Ada-verification environment. The Penelope user inputs mathematical definitions, Larch-style specifications and Ada code and performs machine-assisted proofs that the code obeys its specifications. As an example, the verification of a binary search function is considered. Emphasis is given to techniques assisting the reuse of a verification effort on modified code.

  17. Anaphoric Descriptions

    ERIC Educational Resources Information Center

    Beller, Charley

    2013-01-01

    The study of definite descriptions has been a central part of research in linguistics and philosophy of language since Russell's seminal work "On Denoting" (Russell 1905). In that work Russell quickly dispatches analyses of denoting expressions with forms like "no man," "some man," "a man," and "every…

  18. Pedagogical basis of DAS formalism in engineering education

    NASA Astrophysics Data System (ADS)

    Hiltunen, J.; Heikkinen, E.-P.; Jaako, J.; Ahola, J.

    2011-03-01

    The paper presents a new approach for a bachelor-level curriculum structure in engineering. The approach is called DAS formalism according to its three phases: description, analysis and synthesis. Although developed specifically for process and environmental engineering, DAS formalism has a generic nature and it could also be used in other engineering fields. The motivation for this new curriculum structure originates from the urge to solve the problems that engineering education has faced during the past decades, e.g. student recruitment problems and dissatisfactory learning outcomes. The focus of this paper is on the structure of the curriculum but the content is also discussed when it has an effect on the structure and its implementation. The presented structure, i.e. DAS formalism, builds upon the ideas of some classical pedagogical theories, which have regularly been applied at course level but seldom used to solve curriculum-level issues.

  19. The Formal Semantics of PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan

    1999-01-01

    A specification language is a medium for expressing what is computed rather than how it is computed. Specification languages share some features with programming languages but are also different in several important ways. For our purpose, a specification language is a logic within which the behavior of computational systems can be formalized. Although a specification can be used to simulate the behavior of such systems, we mainly use specifications to state and prove system properties with mechanical assistance. We present the formal semantics of the specification language of SRI's Prototype Verification System (PVS). This specification language is based on the simply typed lambda calculus. The novelty in PVS is that it contains very expressive language features whose static analysis (e.g., typechecking) requires the assistance of a theorem prover. The formal semantics illuminates several of the design considerations underlying PVS, the interaction between theorem proving and typechecking.

  20. Formal verification of mathematical software

    NASA Technical Reports Server (NTRS)

    Sutherland, D.

    1984-01-01

    Methods are investigated for formally specifying and verifying the correctness of mathematical software (software which uses floating point numbers and arithmetic). Previous work in the field was reviewed. A new model of floating point arithmetic called the asymptotic paradigm was developed and formalized. Two different conceptual approaches to program verification, the classical Verification Condition approach and the more recently developed Programming Logic approach, were adapted to use the asymptotic paradigm. These approaches were then used to verify several programs; the programs chosen were simplified versions of actual mathematical software.

  1. [Descriptive statistics].

    PubMed

    Rendón-Macías, Mario Enrique; Villasís-Keever, Miguel Ángel; Miranda-Novales, María Guadalupe

    2016-01-01

    Descriptive statistics is the branch of statistics that gives recommendations on how to summarize clearly and simply research data in tables, figures, charts, or graphs. Before performing a descriptive analysis it is paramount to summarize its goal or goals, and to identify the measurement scales of the different variables recorded in the study. Tables or charts aim to provide timely information on the results of an investigation. The graphs show trends and can be histograms, pie charts, "box and whiskers" plots, line graphs, or scatter plots. Images serve as examples to reinforce concepts or facts. The choice of a chart, graph, or image must be based on the study objectives. Usually it is not recommended to use more than seven in an article, also depending on its length.

  2. Towards Rapid Re-Certification Using Formal Analysis

    DTIC Science & Technology

    2015-05-01

    the problem… • Brooks’ Law. • Too many cooks! Increases accidental complexity. • “9 women can’t make a baby in 1 month!” 7 What kind of...the analysis determine the impact. • Result: Rapid analysis at recertification (or design ) time. • Focus on the parts that commensurate with...Zumwalt’s radar system, designating it as high- confidentiality data. Application Profile Language Formalization in Description Logic P COLLECT

  3. Formalization of treatment guidelines using Fuzzy Cognitive Maps and semantic web tools.

    PubMed

    Papageorgiou, Elpiniki I; Roo, Jos De; Huszka, Csaba; Colaert, Dirk

    2012-02-01

    Therapy decision making and support in medicine deals with uncertainty and needs to take into account the patient's clinical parameters, the context of illness and the medical knowledge of the physician and guidelines to recommend a treatment therapy. This research study is focused on the formalization of medical knowledge using a cognitive process, called Fuzzy Cognitive Maps (FCMs) and semantic web approach. The FCM technique is capable of dealing with situations including uncertain descriptions using similar procedure such as human reasoning does. Thus, it was selected for the case of modeling and knowledge integration of clinical practice guidelines. The semantic web tools were established to implement the FCM approach. The knowledge base was constructed from the clinical guidelines as the form of if-then fuzzy rules. These fuzzy rules were transferred to FCM modeling technique and, through the semantic web tools, the whole formalization was accomplished. The problem of urinary tract infection (UTI) in adult community was examined for the proposed approach. Forty-seven clinical concepts and eight therapy concepts were identified for the antibiotic treatment therapy problem of UTIs. A preliminary pilot-evaluation study with 55 patient cases showed interesting findings; 91% of the antibiotic treatments proposed by the implemented approach were in fully agreement with the guidelines and physicians' opinions. The results have shown that the suggested approach formalizes medical knowledge efficiently and gives a front-end decision on antibiotics' suggestion for cystitis. Concluding, modeling medical knowledge/therapeutic guidelines using cognitive methods and web semantic tools is both reliable and useful.

  4. Modeling anatomical spatial relations with description logics.

    PubMed Central

    Schulz, S.; Hahn, U.; Romacker, M.

    2000-01-01

    Although spatial relations are essential for the anatomy domain, spatial reasoning is only weakly supported by medical knowledge representation systems. To remedy this shortcoming we express spatial relations that can intuitively be applied to anatomical objects (such as 'disconnected', 'externally connected', 'partial overlap' and 'proper part') within the formal framework of description logics. A special encoding of concept descriptions (in terms of SEP triplets) allows us to emulate spatial reasoning by classification-based reasoning. PMID:11079990

  5. Integrating Formal Methods and Testing 2002

    NASA Technical Reports Server (NTRS)

    Cukic, Bojan

    2002-01-01

    Traditionally, qualitative program verification methodologies and program testing are studied in separate research communities. None of them alone is powerful and practical enough to provide sufficient confidence in ultra-high reliability assessment when used exclusively. Significant advances can be made by accounting not only tho formal verification and program testing. but also the impact of many other standard V&V techniques, in a unified software reliability assessment framework. The first year of this research resulted in the statistical framework that, given the assumptions on the success of the qualitative V&V and QA procedures, significantly reduces the amount of testing needed to confidently assess reliability at so-called high and ultra-high levels (10-4 or higher). The coming years shall address the methodologies to realistically estimate the impacts of various V&V techniques to system reliability and include the impact of operational risk to reliability assessment. Combine formal correctness verification, process and product metrics, and other standard qualitative software assurance methods with statistical testing with the aim of gaining higher confidence in software reliability assessment for high-assurance applications. B) Quantify the impact of these methods on software reliability. C) Demonstrate that accounting for the effectiveness of these methods reduces the number of tests needed to attain certain confidence level. D) Quantify and justify the reliability estimate for systems developed using various methods.

  6. The Traps of Formal Correspondence.

    ERIC Educational Resources Information Center

    Albert, Sandor

    The dangers of translation are discussed when the translator does not try to create textual equivalence, but settles for formal correspondence (i.e., with simple transcoding at a linguistic level) during the process of translating. Difficulties of explaining, commenting, or summarizing rather than translating are also discussed. Pedagogical and…

  7. Formal methods in the development of safety critical software systems

    SciTech Connect

    Williams, L.G.

    1991-11-15

    As the use of computers in critical control systems such as aircraft controls, medical instruments, defense systems, missile controls, and nuclear power plants has increased, concern for the safety of those systems has also grown. Much of this concern has focused on the software component of those computer-based systems. This is primarily due to historical experience with software systems that often exhibit larger numbers of errors than their hardware counterparts and the fact that the consequences of a software error may endanger human life, property, or the environment. A number of different techniques have been used to address the issue of software safety. Some are standard software engineering techniques aimed at reducing the number of faults in a software protect, such as reviews and walkthroughs. Others, including fault tree analysis, are based on identifying and reducing hazards. This report examines the role of one such technique, formal methods, in the development of software for safety critical systems. The use of formal methods to increase the safety of software systems is based on their role in reducing the possibility of software errors that could lead to hazards. The use of formal methods in the development of software systems is controversial. Proponents claim that the use of formal methods can eliminate errors from the software development process, and produce programs that are probably correct. Opponents claim that they are difficult to learn and that their use increases development costs unacceptably. This report discusses the potential of formal methods for reducing failures in safety critical software systems.

  8. Anterior clinoidectomy: Description of an alternative hybrid method and a review of the current techniques with an emphasis on complication avoidance

    PubMed Central

    Kulwin, Charles; Tubbs, R. Shane; Cohen-Gadol, Aaron A.

    2011-01-01

    Background: Anterior clinoidectomy is a difficult but important part of surgery for a variety of parasellar, proximal carotid and central skull base pathologies. First developed intradurally nearly 60 years ago, the promotion of an extradural technique decades later offered an approach with a different set of difficulties, risks and benefits. Many recent studies have demonstrated that there is no consensus about the “correct side” of the dura from which to remove the anterior clinoid process in a number of pathologies. Here, we review and compare the current techniques for intra- and extradural clinoidectomy and describe a hybrid alternative technique. Methods: We used a hybrid method to potentially engage the advantages of the intradural and extradural techniques. The hybrid method starts with an extradural sphenoid wing osteotomy to the level of the superior orbital fissure (SOF). The dura is then incised parallel to the sphenoid wing lateral to the SOF, and the need for further bony removal, including clinoidectomy, is assessed after gentle elevation of the frontal lobe and release of cerebrospinal fluid through opening the optico-carotid cisterns and inspection of the pathology in relation to the clinoid. Sylvian fissure may be dissected to relieve retraction on the frontal lobe. Results: The hybrid method allows an early identification of the optic nerve and its protection during clinoidectomy. The operator leaves the dura medial to the SOF intact and the clionoidectomy proceeds in an extradural fashion while intradural inspection periodically is performed to assess the extent of necessary extradural bony removal. Conclusion: The hybrid method theoretically can be used as a versatile method under some circumstances. Cutting the dura along the sphenoid wing will prevent the dural layers from obscuring the clinoid and offers intradural visualization to monitor the lesion and potentially tailor bony removal. PMID:22059135

  9. Quantitative analysis of growth factors from a second filter using the Reamer-Irrigator-Aspirator system: description of a novel technique.

    PubMed

    Stannard, James P; Sathy, Ashoke K; Moeinpour, Fariba; Stewart, Rena L; Volgas, David A

    2010-01-01

    Use of the Reamer-Irrigator-Aspirator (RIA) as a source of autogenous bone graft in the treatment of nonunions is increasing. We report on our novel technique of using a second filter containing beta-tricalcium phosphate (TCP) as a graft extender while using the RIA system. We also quantify growth factor concentrations in the collections from the TCP filter. A second filter attached in series with the standard RIA filtration system yields TCP with substantial concentrations of bioactive proteins that are equal to those seen in the bone graft that is harvested in the first filter.

  10. Formal reasoning on qualitative models of coinfection of HIV and Tuberculosis and HAART therapy

    PubMed Central

    2010-01-01

    descriptions that suitably account for aspects of interests; iii) suggest that the integration of different models together with automated reasoning techniques can improve the understanding of infections and therapies through formal analysis methodologies. Conclusion We argue that the described methodology suitably supports the study of viral infections in a formal, automated and expressive manner. We envisage a long-term contribution of this kind of approaches to clinical Bioinformatics and Translational Medicine. PMID:20122243

  11. Geomechanical Facies Concept In Fractured Resevoirs and the Application of Hybrid Numerical and Analytical Techniques for the Description of Coupled Transport In Fractured Systems

    NASA Astrophysics Data System (ADS)

    McDermott, C. I.; Wenqing, W.; Kolditz, O.

    2009-04-01

    Exploiting and geo-engineering of fractured rocks in the context of reservoir storage and utilisation is important to applications such as hydrogeology, petroleum geology, geothermal energy, nuclear waste storage and CO2-sequestration. Understanding fluid, mass and energy transport in the three dimensional fracture network is critical to the evaluation planned operating efficiency. Hydraulic, thermal, mechanical and chemical coupled processes under the typical reservoir conditions operate at different scales. Depending on whether the process is continuum dominated (e.g. transfer of stress in the rock body) or discontinuity dominated (e.g. hydraulic transport processes) different methods of numerically investigating and quantifying the system can be applied. A geomechanical facies approach provides the basis for large scale numerical analysis of the coupled processes and prediction of system response. It also provides the basis for a three dimensional holistic understanding of the reservoir systems and the appropriate investigation techniques which could be used to evaluate the capacities of the reservoirs to be investigated as well as appropriate development techniques. Concentrating on the numerical modelling there is often a difficult balance between the numerical stability criteria of the different equation systems which need to be solved to describe the interaction of the dominant processes. The introduction of analytical solutions where possible, functional dependencies and multiple meshes provides on the framework of the geo-mechanical facies concept provides an efficient and stable method for the prediction of the effect of the in situ coupling.

  12. A very general electromagnetic gyrokinetic formalism

    NASA Astrophysics Data System (ADS)

    McMillan, B. F.; Sharma, A.

    2016-09-01

    We derive a gyrokinetic formalism which is very generally valid: the ordering allows both large inhomogeneities in plasma flow and magnetic field at long wavelength, such as typical drift-kinetic theories, as well as fluctuations at the gyro-scale. The underlying approach is to order the vorticity to be small, and to assert that the timescales in the local plasma frame are long compared to the gyrofrequency. Unlike most other derivations, we do not treat the long and short wavelength components of the fluctuating fields separately; the single-field description defines the particle motion and their interaction with the electromagnetic field at small-scale, the system-scale, and intermediate length scales in a unified fashion. As in earlier literature, the work consists of identifying a coordinate system where the gyroangle-dependent terms are small, and using a near-unity transform to systematically find a set of coordinates where the gyroangle dependence vanishes. We derive a gyrokinetic Lagrangian which is valid where the vorticity | ∇ × ( E × B / B ) | is small compared to the gyrofrequency Ω, and the magnetic field scale length is long compared to the gyroradius; we also require that time variation be slow in an appropriately chosen reference frame. This appears to be a minimum set of constraints on a gyrokinetic theory and is substantially more general than earlier approaches. It is the general-geometry electromagnetic extension of Dimits, Phys. Plasmas 17, 055901 (2010) (which is an electrostatic formalism with a homogeneous background magnetic field). This approach also does not require a separate treatment of fluctuating and background components of the magnetic field, unlike much of the previous literature. As a consequence, the "cross terms" due to a combination of long- and short-wavelength variation, which were ignored in the earlier work (but derived in a more restrictive ordering in Parra and Calvo, Plasma Phys. Controlled Fusion 53, 045001 (2011

  13. Proceedings of the First NASA Formal Methods Symposium

    NASA Technical Reports Server (NTRS)

    Denney, Ewen (Editor); Giannakopoulou, Dimitra (Editor); Pasareanu, Corina S. (Editor)

    2009-01-01

    Topics covered include: Model Checking - My 27-Year Quest to Overcome the State Explosion Problem; Applying Formal Methods to NASA Projects: Transition from Research to Practice; TLA+: Whence, Wherefore, and Whither; Formal Methods Applications in Air Transportation; Theorem Proving in Intel Hardware Design; Building a Formal Model of a Human-Interactive System: Insights into the Integration of Formal Methods and Human Factors Engineering; Model Checking for Autonomic Systems Specified with ASSL; A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process; Software Model Checking Without Source Code; Generalized Abstract Symbolic Summaries; A Comparative Study of Randomized Constraint Solvers for Random-Symbolic Testing; Component-Oriented Behavior Extraction for Autonomic System Design; Automated Verification of Design Patterns with LePUS3; A Module Language for Typing by Contracts; From Goal-Oriented Requirements to Event-B Specifications; Introduction of Virtualization Technology to Multi-Process Model Checking; Comparing Techniques for Certified Static Analysis; Towards a Framework for Generating Tests to Satisfy Complex Code Coverage in Java Pathfinder; jFuzz: A Concolic Whitebox Fuzzer for Java; Machine-Checkable Timed CSP; Stochastic Formal Correctness of Numerical Algorithms; Deductive Verification of Cryptographic Software; Coloured Petri Net Refinement Specification and Correctness Proof with Coq; Modeling Guidelines for Code Generation in the Railway Signaling Context; Tactical Synthesis Of Efficient Global Search Algorithms; Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems; and Formal Methods for Automated Diagnosis of Autosub 6000.

  14. Formal Dining-In Handbook

    DTIC Science & Technology

    1983-01-01

    variety of source material. The primary research document was the booklet, Formal Dining -In, published by the 1st Battalion, The School E rigade , United...CHAPTER 1: Background on British Regimental Mess, CHAPTER II: Background on US Regimental b Mess: CHAPTER III: Standards for Dining-In 9 CHAPTER IV: E ...entertaining guests in the surroundings of traditions and customs of the regiment, served to make the officers aware of the luxuries of life . Young

  15. Formal properties of the Metathesaurus.

    PubMed

    Tuttle, M S; Olson, N E; Campbell, K E; Sherertz, D D; Nelson, S J; Cole, W G

    1994-01-01

    The Metathesaurus is a machine-created, human edited and enhanced synthesis of authoritative biomedical terminologies. Its formal properties permit it to be a) exploited by computers, and b) modified and enhanced without compromising that usage. If further constraints were imposed on the existence and identity of Metathesaurus relationships, i.e., if every Metathesaurus concept had a "genus" and a "differentia," then the Metathesaurus could be converted into an "Aristotelian Hierarchy." In this sense, a genus is a concept that classifies another concept, and a differentia is a concept that distinguishes the classified concept from all other concepts in the same class. Since, in principle, these constraints would make the Metathesaurus easier to leverage and maintain computationally, it is interesting to ask to what degree the maintenance and enhancement procedures now in place are producing a Metathesaurus that is also an "Aristotelian Hierarchy." Given a liberal interpretation of the current Metathesaurus schema, the proportion of the Metathesaurus that is "Aristotelian" in each annual version is increasing in spite of dramatic concurrent increases in the number of Metathesaurus concepts. Without formality there is no modifiability nor scalability. [1] We need formal methods and computer-based tools that can help us with the task [of controlled medical vocabulary construction]. We need research in which controlled vocabulary development is the focus rather than a stepping stone for work on other theories and applications. [2

  16. Percutaneous reduction and fixation of an intra-articular calcaneal fracture using an inflatable bone tamp: description of a novel and safe technique

    PubMed Central

    2012-01-01

    Calcaneal fractures are common injuries involving the hind foot and often a source of significant long-term morbidity. Treatment options have changed throughout the ages from periods of preferred nonoperative management to closed reduction with a mallet, and more recently, open reduction and anatomic internal fixation. The current treatment of choice; however, is often debated, as open management of these fractures carries many risks to include wound breakdown and infection. A less invasive form of surgical management through small incisions, while maintaining the ability to obtain joint congruency, anatomic alignment, and restore calcaneal height and width would be ideal. We propose a novel form of fracture reduction using an inflatable bone tamp and percutaneous fracture fixation. Preoperative planning and experienced fluoroscopy is crucial to successful management using this method. Although we achieved successful radiographic outcome in this case, long-term functional outcome of this technique are yet to be published. PMID:22420710

  17. Posterior C1-C2 Fixation Using Absorbable Suture for Type II Odontoid Fracture in 2-Year-Old Child: Description of a New Technique and Literature Review.

    PubMed

    Labbe, Jean L; Peres, Olivier; Leclair, Olivier; Goulon, Renaud; Scemama, Patrice; Jourdel, François; Bertrou, Véronique; Murgier, Jerome

    2016-12-01

    Odontoid synchondrosis fractures are rare in children, even though they are the more common cervical fracture in children less than 7 years old. Nonoperative treatment with external orthosis immobilization is the treatment of choice for stable undisplaced or minimally displaced injuries. In unstable fractures, when reduction cannot be achieved or maintained, surgical fixation is recommended. We report a 2-year-old boy with an unstable fracture of the odontoid treated surgically using an absorbable monofilament suture for C1-C2 interlaminar fixation without bone grafting. This suture was strong enough to provide the stability necessary to allow healing of the synchondrosis and the delayed resorption of the suture was followed by complete restoration of the mobility between C1 and C2. This case illustrates that surgical stabilization using an absorbable suture in young children with an unstable odontoid fracture is a safe and effective alternative to other surgical techniques.

  18. Heat-flux measurements for the rotor of a full-stage turbine. II - Description of analysis technique and typical time-resolved measurements

    NASA Technical Reports Server (NTRS)

    Dunn, M. G.; George, W. K.; Rae, W. J.; Woodward, S. H.; Moller, J. C.

    1986-01-01

    An analytical technique for obtaining the time-resolved heat flux of a turbine blade is applied to the case of a TFE 731-2 hp full-stage rotating turbine. In order to obtain the heat flux values from the thin film gage temperature histories, a finite difference procedure is used to solve the heat equation with variable thermal properties. After setting out the data acquisition and analysis procedures, their application is illustrated for three midspan locations on the blade and operation at the design flow function. Results demonstrate that the magnitude of the heat flux fluctuation due to vane-balde interaction is large by comparison to the time-averaged heat flux at all investigated locations; FFT of a portion of the heat flux record illustrates that the dominant frequencies occur at the wake-cutting frequency and its harmonics.

  19. Peer Review of a Formal Verification/Design Proof Methodology

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The role of formal verification techniques in system validation was examined. The value and the state of the art of performance proving for fault-tolerant compuers were assessed. The investigation, development, and evaluation of performance proving tools were reviewed. The technical issues related to proof methodologies are examined. The technical issues discussed are summarized.

  20. Proceedings of the Sixth NASA Langley Formal Methods (LFM) Workshop

    NASA Technical Reports Server (NTRS)

    Rozier, Kristin Yvonne (Editor)

    2008-01-01

    Today's verification techniques are hard-pressed to scale with the ever-increasing complexity of safety critical systems. Within the field of aeronautics alone, we find the need for verification of algorithms for separation assurance, air traffic control, auto-pilot, Unmanned Aerial Vehicles (UAVs), adaptive avionics, automated decision authority, and much more. Recent advances in formal methods have made verifying more of these problems realistic. Thus we need to continually re-assess what we can solve now and identify the next barriers to overcome. Only through an exchange of ideas between theoreticians and practitioners from academia to industry can we extend formal methods for the verification of ever more challenging problem domains. This volume contains the extended abstracts of the talks presented at LFM 2008: The Sixth NASA Langley Formal Methods Workshop held on April 30 - May 2, 2008 in Newport News, Virginia, USA. The topics of interest that were listed in the call for abstracts were: advances in formal verification techniques; formal models of distributed computing; planning and scheduling; automated air traffic management; fault tolerance; hybrid systems/hybrid automata; embedded systems; safety critical applications; safety cases; accident/safety analysis.

  1. The Carcinogenic Liver Fluke Opisthorchis viverrini among Rural Community People in Northeast Thailand: a Cross- Sectional Descriptive Study using Multistage Sampling Technique.

    PubMed

    Kaewpitoon, Soraya J; Kaewpitoon, Natthawut; Rujirakul, Ratana; Ueng-Arporn, Naporn; Matrakool, Likit; Tongtawee, Taweesak

    2015-01-01

    Opisthorchis viverrini infection is a serious public health problem in Southeast Asia especially in the northeast and north of Thailand. Therefore, a cross-sectional survey using multistage sampling was conducted from the rural communities of Surin province, Thailand, during September 2013 to July 2014. O. viverrini infection was determined using Kato's thick smear technique. Socio-demographic, information resources, and history data were collected using predesigned semi-structured questionnaires. A total of 510 participants completed interviews and had stools collected. Some 32 (6.47%) participants were infected with O. viverrini. The rate was slightly higher in males (6.61%) than females (6.32%). High frequencies were found in the age groups 61-70 (19.4%) and 71-80 years (19.4%), those involved in agriculture (10.5%), and in primary school (10.3%). The distribution of high infection was found in Tha Tum (16.7%) and Sankha district (16.7%), followed by Samrong Thap (13.3%), Si Narong (13.33%), and Buachet district (13.33%). Chi-square testing indicated that age (61-70 and 71-80 year old), education (primary school) and occupation (agriculture), were significantly associated with O. viverrini infection (p-value<0.05). Of 72.6% participants who had past histories with stool examination, 17.0% of them had been infected with O. viverrini and 43.2% treated with praziquantel. This finding confirmed that O. viverrini is still a problem in Surin province, Thailand, and therefore, interventions are urgently required for mass treatment and health education implementation.

  2. Descriptive thermodynamics

    NASA Astrophysics Data System (ADS)

    Ford, David; Huntsman, Steven

    2006-06-01

    Thermodynamics (in concert with its sister discipline, statistical physics) can be regarded as a data reduction scheme based on partitioning a total system into a subsystem and a bath that weakly interact with each other. Whereas conventionally, the systems investigated require this form of data reduction in order to facilitate prediction, a different problem also occurs, in the context of communication networks, markets, etc. Such “empirically accessible” systems typically overwhelm observers with the sort of information that in the case of (say) a gas is effectively unobtainable. What is required for such complex interacting systems is not prediction (this may be impossible when humans besides the observer are responsible for the interactions) but rather, description as a route to understanding. Still, the need for a thermodynamical data reduction scheme remains. In this paper, we show how an empirical temperature can be computed for finite, empirically accessible systems, and further outline how this construction allows the age-old science of thermodynamics to be fruitfully applied to them.

  3. Effects of rapid eye movement sleep deprivation on the feeding behavior in the laboratory rat with a description of the cuff pedestal technique.

    PubMed

    Elomaa, E

    1985-01-01

    The cuff pedestal technique, with which it is possible to use the test animal as its own control both before and after REMs deprivation, was described. The validity of this modified procedure for REMs deprivation was tested with reference to the electrophysiological sleep correlates using 6 adult rats deprived of REMs for 3 days. The stress effects of the cuff pedestal treatment were assessed in terms of adrenal weights in 12 rats. The duration of REMs deprivation in this experiment was 5 days. The effects of REMs deprivation on locomotor activity and food intake were studied in 8 juvenile rats exposed to REMs deprivation by lowering the cuffs for 6 days after 3 baseline days with the cuffs raised. 24 h recordings of meal pattern data were obtained from 8 adult rats during one baseline day, during the first and sixth day of REMs deprivation and during the second day after termination of REMs deprivation. The main results were as follows: The procedure of placing experimentally naive rats on small pedestals surrounded by water inhibited normal food intake for several days. Concomitant weight losses were of the same order as have been reported to occur in control rats on large pedestals. This finding suggests that both the large and small pedestals should be equipped with movable cuffs and that actual deprivation should be started by lowering the cuffs only when the animals have exceeded their original weights. The electrophysiological sleep/waking cycle of rats adapted to living on the pedestal with the cuff raised was similar to that reported in rats under ordinary laboratory conditions. Lowering of the cuffs for 3 days resulted in an almost total disappearance of REMs. A prominent rebound increase of REMs occurred after raising of the cuffs. Rats kept for fourteen days on pedestals with the cuffs raised displayed an increase of about 20% in the weights of the adrenal bodies. A quite similar adrenal hypertrophy, however, also occurs in rats living under enriched

  4. The formal de Rham complex

    NASA Astrophysics Data System (ADS)

    Zharinov, V. V.

    2013-02-01

    We propose a formal construction generalizing the classic de Rham complex to a wide class of models in mathematical physics and analysis. The presentation is divided into a sequence of definitions and elementary, easily verified statements; proofs are therefore given only in the key case. Linear operations are everywhere performed over a fixed number field {F} = {R},{C}. All linear spaces, algebras, and modules, although not stipulated explicitly, are by definition or by construction endowed with natural locally convex topologies, and their morphisms are continuous.

  5. Knowledge formalization of intelligent building

    NASA Astrophysics Data System (ADS)

    Žáček, Martin

    2016-06-01

    This article aim is understanding the basic knowledge about an intelligent building. The notion of the intelligent building can be called any building equipped with computer and communication technology, which can automatically respond to internal or external stimuli. The result of the intelligent building is an automated and foreseeing of activities that enable to reduce operating costs and increase comfort. The best way to use the intelligent building is for a low-energy building, a passive building, or for building with high savings. The output of this article is the formalization of basic knowledge of the intelligent building by RDF graph.

  6. Formalizing the Analysis of Algorithms.

    DTIC Science & Technology

    1979-06-01

    worst case or in the average case. For the parameter A, the worst case analysis is no challenge . First, since the if-test is only performed once per...use of a counter variable; this approach was introduced by Knuth [ exercise 1.2.1-13 in 18]. We can add to the program a new variable C, set initially...encoded. Value of the Proposed System. It is worthwhile pausing for a moment to attempt to assess the benefits that such a formal system might have

  7. On Vasyliunas's equivalent conductivity formalism

    NASA Technical Reports Server (NTRS)

    Pontius, D. H., Jr.

    1992-01-01

    The Vasyliunas's (1972) equivalent conductivity formalism (ECF) for representing the coupling of the ionosphere and the magnetosphere is discussed, and a new, simpler, derivation is presented of the ECF, in which certain of the underlying assumptions and their implications are made transparent. The derivation presented indicates that the only role of the ions in the ECF is to insure quasi-neutrality. It is shown that the ECF is not as robust as usually assumed and that caution must be used to insure that reasonable results are obtained.

  8. Formal Computer Validation of the Quantum Phase Estimation Algorithm

    NASA Astrophysics Data System (ADS)

    Witzel, Wayne; Rudinger, Kenneth; Sarovar, Mohan; Carr, Robert

    While peer review and scientific consensus provide some assurance to the validity of ideas, people do make mistakes that can slip through the cracks. A plethora of formal methods tools exist and are in use in a variety of settings where high assurance is demanded. Existing tools, however, require a great deal of expertise and lack versatility, demanding a non-trivial translation between a high-level description of a problem and the formal system. Our software, called Prove-It, allows a nearly direct translation between human-recognizable formulations and the underlying formal system. While Prove-It is not designed for particularly efficient automation, a primary goal of other formal methods tools, it is extremely flexible in following a desired line of reasoning (proof structure). This approach is particularly valuable for validating proofs that are already known. We will demonstrate a validation of the Quantum Phase Estimation Algorithm using Prove-It. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. This work was supported by the Laboratory Directed Research and Development program at Sandia National Laboratories.

  9. 47 CFR 8.12 - Formal complaints.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....

  10. 47 CFR 8.12 - Formal complaints.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....

  11. 47 CFR 8.12 - Formal complaints.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Formal complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal complaints. Any person may file a formal complaint alleging a violation of the rules in this part....

  12. 47 CFR 8.12 - Formal Complaints.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Formal Complaints. 8.12 Section 8.12 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.12 Formal Complaints. Any person may file a formal complaint alleging a violation of the rules in this part....

  13. Formal policies for flexible EHR security.

    PubMed

    Blobel, Bernd; Pharow, Peter

    2006-01-01

    State of the Art methodologies for establishing requirements and solutions to securing applications are based on narrative descriptions about the use of available system, sometimes also dedicated to system components. Even nowadays new developments to ruling application security services by the use of predicate logic suffer from being administered manually. Therefore, security and privacy requirements cannot be properly met resulting in restrictions and fears for allowing the use of sensitive data and functions. Because of the sensitivity of personal health information and especially of genetic data with its wider implications beyond the original subject of care, weaknesses in guaranteeing fine-grained security and privacy rules lead to less acceptance or even the avoidance of essential information transfer and use. To overcome the problem, security and privacy have to become properties of the architectural components of the respective health information system. Embedding security into the systems architecture allows for negotiating and enforcing any security and privacy services related to principals, their roles, their relationships, further contextual information as well as other regulations summarized in formally modeled policies. The paper introduces the evolving paradigm of the model-driven architecture, first time also comprehensively deployed for security and privacy services in bio-genetic and health information systems.

  14. What's in a code? Towards a formal account of the relation of ontologies and coding systems.

    PubMed

    Rector, Alan L

    2007-01-01

    Terminologies are increasingly based on "ontologies" developed in description logics and related languages such as the new Web Ontology Language, OWL. The use of description logic has been expected to reduce ambiguity and make it easier determine logical equivalence, deal with negation, and specify EHRs. However, this promise has not been fully realised: in part because early description logics were relatively inexpressive, in part, because the relation between coding systems, EHRs, and ontologies expressed in description logics has not been fully understood. This paper presents a unifying approach using the expressive formalisms available in the latest version of OWL, OWL 1.1.

  15. A Formal Approach to Requirements-Based Programming

    NASA Technical Reports Server (NTRS)

    Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

    2005-01-01

    No significant general-purpose method is currently available to mechanically transform system requirements into a provably equivalent model. The widespread use of such a method represents a necessary step toward high-dependability system engineering for numerous application domains. Current tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The "gap" unfilled by such tools and methods is that the formal models cannot be proven to be equivalent to the requirements. We offer a method for mechanically transforming requirements into a provably equivalent formal model that can be used as the basis for code generation and other transformations. This method is unique in offering full mathematical tractability while using notations and techniques that are well known and well trusted. Finally, we describe further application areas we are investigating for use of the approach.

  16. Why formal learning theory matters for cognitive science.

    PubMed

    Fulop, Sean; Chater, Nick

    2013-01-01

    This article reviews a number of different areas in the foundations of formal learning theory. After outlining the general framework for formal models of learning, the Bayesian approach to learning is summarized. This leads to a discussion of Solomonoff's Universal Prior Distribution for Bayesian learning. Gold's model of identification in the limit is also outlined. We next discuss a number of aspects of learning theory raised in contributed papers, related to both computational and representational complexity. The article concludes with a description of how semi-supervised learning can be applied to the study of cognitive learning models. Throughout this overview, the specific points raised by our contributing authors are connected to the models and methods under review.

  17. Formal Attributes of Television Commercials: Subtle Ways of Transmitting Sex Stereotypes.

    ERIC Educational Resources Information Center

    Welch, Renate L.; And Others

    Differences in formal aspects of television commercials aimed at boys and those aimed at girls were investigated. Formal attributes were defined as production techniques such as action, pace, visual effects, dialogue and narration, background music and sound effects. Two aspects of content were also examined: aggressive behavior and the gender of…

  18. Hamiltonian Description of Multi-fluid Streaming

    NASA Astrophysics Data System (ADS)

    Valls, C.; de La Llave, R.; Morrison, P. J.

    2001-10-01

    The general noncanonical Hamiltonian description of interpenetrating fluids coupled by electrostatic, gravitational, or other forces is presented. This formalism is used to describe equilibrium and nonlinear stability using techniques of Hamiltonian dynamics theory. For example, we study the stability of two warm counter-streaming electron beams in a neutralizing ion background. The normal modes are obtained from an energy functional by computing the lowest-order expression for the perturbed energy about an equilibrium, and transforming the corresponding system into action-angle variables. Higher-order terms in the Hamiltonian provide coupling between normal modes and can lead to instability because of the presence of negative energy modes (NEM's). (The signature of the NEM's is determined by the signature of the Hamiltonian, Moser's bracket definition, or the conventional plasma definition in terms of the dielectric function, all of which are shown to be equivalent.) The possible nonlinear behavior is discovered by constructing the Birkhoff normal form. Accounting for resonances, we transform away terms in the Hamiltonian to address the question of long-time stability for such systems.

  19. A Comparison of Participation Patterns in Selected Formal, Non-Formal, and Informal Online Learning Environments

    ERIC Educational Resources Information Center

    Schwier, Richard A.; Seaton, J. X.

    2013-01-01

    Does learner participation vary depending on the learning context? Are there characteristic features of participation evident in formal, non-formal, and informal online learning environments? Six online learning environments were chosen as epitomes of formal, non-formal, and informal learning contexts and compared. Transcripts of online…

  20. Formal methods technology transfer: Some lessons learned

    NASA Technical Reports Server (NTRS)

    Hamilton, David

    1992-01-01

    IBM has a long history in the application of formal methods to software development and verification. There have been many successes in the development of methods, tools and training to support formal methods. And formal methods have been very successful on several projects. However, the use of formal methods has not been as widespread as hoped. This presentation summarizes several approaches that have been taken to encourage more widespread use of formal methods, and discusses the results so far. The basic problem is one of technology transfer, which is a very difficult problem. It is even more difficult for formal methods. General problems of technology transfer, especially the transfer of formal methods technology, are also discussed. Finally, some prospects for the future are mentioned.

  1. Formal Techniques in the Management of Software Design.

    DTIC Science & Technology

    1983-06-17

    cursor coordinate screendoff coordinate -’insertmode boolean arrowcommand: boolean start coordinate stop coordinate ’ magline SEQ [speck] * %%USEFUL...8217 - false magline ’ - blankmsg show* tabletop M% select a legal but unused name. where newname a r-(docname -dom (docdatal)) DTHROW d docname M% certain...cam’) - aeie(a) insrtmdel- false arrowcommand’ - false magline ’ - blankmsg where a Bprojview (vpno) IA h.. PROJCREATR * AUMACH INE %%there must be room

  2. Tensor formalism in anharmonic calculations

    NASA Astrophysics Data System (ADS)

    Nero, N.

    1984-11-01

    A new method is presented to compute cartesian tensors in the expansion of curvilinear internal coordinates. Second- and higher-order coefficients are related to the metrics of the space of displacements. Components of the metric tensor are taken from existing tables of inverse kinetic energy matrix elements or, when rotations are involved, derived from general invariance conditions of scalars within a molecule. This leads to a tensor formalism particularly convenient in dealing with curvilinear coordinates in anharmonic calculations of vibrational frequencies. Formulae are given for elements of the potential energy matrix, related to quadratic and cubic force constants in terms of Christoffel symbols. The latter quantities are also used in the expansion of redundancy relations, with explicit coefficients given up to the third order.

  3. Galilei invariant technique for quantum system description

    SciTech Connect

    Kamuntavičius, Gintautas P.

    2014-04-15

    Problems with quantum systems models, violating Galilei invariance are examined. The method for arbitrary non-relativistic quantum system Galilei invariant wave function construction, applying a modified basis where center-of-mass excitations have been removed before Hamiltonian matrix diagonalization, is developed. For identical fermion system, the Galilei invariant wave function can be obtained while applying conventional antisymmetrization methods of wave functions, dependent on single particle spatial variables.

  4. Identification and Description of Geophysical Techniques.

    DTIC Science & Technology

    1980-11-01

    for reaction with groundwater and pollutants. Shales and clays, for example, have the po- tential for concentrating certain ions by the processes of...8217tured shale unit. Geophysical expression of lithology can include acoustic velocity, electrical resistivity, spontaneous potential, density, gamma...the travel time required for acoustic compressional waves, generated in the earth by a near-surface explosion, mechanical impact, or vibration , to

  5. Cooperativity and saturation in biochemical networks: a saturable formalism using Taylor series approximations.

    PubMed

    Sorribas, Albert; Hernández-Bermejo, Benito; Vilaprinyo, Ester; Alves, Rui

    2007-08-01

    Cooperative and saturable systems are common in molecular biology. Nevertheless, common canonical formalisms for kinetic modeling that are theoretically well justified do not have a saturable form. Modeling and fitting data from saturable systems are widely done using Hill-like equations. In practice, there is no theoretical justification for the generalized use of these equations, other than their ability to fit experimental data. Thus it is important to find a canonical formalism that is (a) theoretically well supported, (b) has a saturable functional form, and (c) can be justifiably applicable to any biochemical network. Here we derive such a formalism using Taylor approximations in a special transformation space defined by power-inverses and logarithms of power-inverses. This formalism is generalized for processes with n-variables, leading to a useful mathematical representation for molecular biology: the Saturable and Cooperative Formalism (SC formalism). This formalism provides an appropriate representation that can be used for modeling processes with cooperativity and saturation. We also show that the Hill equation can be seen as a special case within this formalism. Parameter estimation for the SC formalism requires information that is also necessary to build Power-Law models, Metabolic Control Analysis descriptions or (log)linear and Lin-log models. In addition, the saturation fraction of the relevant processes at the operating point needs to be considered. The practical use of the SC formalism for modeling is illustrated with a few examples. Similar models are built using different formalisms and compared to emphasize advantages and limitations of the different approaches.

  6. Auteur Description: From the Director's Creative Vision to Audio Description

    ERIC Educational Resources Information Center

    Szarkowska, Agnieszka

    2013-01-01

    In this report, the author follows the suggestion that a film director's creative vision should be incorporated into Audio description (AD), a major technique for making films, theater performances, operas, and other events accessible to people who are blind or have low vision. The author presents a new type of AD for auteur and artistic films:…

  7. M-Theory in the Gaugeon Formalism

    NASA Astrophysics Data System (ADS)

    Mir, Faizal

    2012-04-01

    In this paper we will analyse the Aharony-Bergman-Jafferis-Maldacena (ABJM) theory in superspace formalism. We then study the quantum gauge transformations for this ABJM theory in gaugeon formalism. We will also analyse the extended BRST symmetry for this ABJM theory in gaugeon formalism and show that these BRST transformations for this theory are nilpotent and this in turn leads to the unitary evolution of the S-matrix.

  8. Survey of Existing Tools for Formal Verification.

    SciTech Connect

    Punnoose, Ratish J.; Armstrong, Robert C.; Wong, Matthew H.; Jackson, Mayo

    2014-12-01

    Formal methods have come into wide use because of their effectiveness in verifying "safety and security" requirements of digital systems; a set of requirements for which testing is mostly ineffective. Formal methods are routinely used in the design and verification of high-consequence digital systems in industry. This report outlines our work in assessing the capabilities of commercial and open source formal tools and the ways in which they can be leveraged in digital design workflows.

  9. Third NASA Langley Formal Methods Workshop

    NASA Technical Reports Server (NTRS)

    Holloway, C. Michael (Compiler)

    1995-01-01

    This publication constitutes the proceedings of NASA Langley Research Center's third workshop on the application of formal methods to the design and verification of life-critical systems. This workshop brought together formal methods researchers, industry engineers, and academicians to discuss the potential of NASA-sponsored formal methods and to investigate new opportunities for applying these methods to industry problems. contained herein are copies of the material presented at the workshop, summaries of many of the presentations, a complete list of attendees, and a detailed summary of the Langley formal methods program. Much of this material is available electronically through the World-Wide Web via the following URL.

  10. The Second NASA Formal Methods Workshop 1992

    NASA Technical Reports Server (NTRS)

    Johnson, Sally C. (Compiler); Holloway, C. Michael (Compiler); Butler, Ricky W. (Compiler)

    1992-01-01

    The primary goal of the workshop was to bring together formal methods researchers and aerospace industry engineers to investigate new opportunities for applying formal methods to aerospace problems. The first part of the workshop was tutorial in nature. The second part of the workshop explored the potential of formal methods to address current aerospace design and verification problems. The third part of the workshop involved on-line demonstrations of state-of-the-art formal verification tools. Also, a detailed survey was filled in by the attendees; the results of the survey are compiled.

  11. Anyons in the operational formalism

    SciTech Connect

    Neori, Klil H.; Goyal, Philip

    2015-01-13

    The operational formalism to quantum mechanics seeks to base the theory on a firm foundation of physically well-motivated axioms [1]. It has succeeded in deriving the Feynman rules [2] for general quantum systems. Additional elaborations have applied the same logic to the question of identical particles, confirming the so-called Symmetrization Postulate [3]: that the only two options available are fermions and bosons [4, 5]. However, this seems to run counter to results in two-dimensional systems, which allow for anyons, particles with statistics which interpolate between Fermi-Dirac and Bose-Einstein (see [6] for a review). In this talk we will show that the results in two dimensions can be made compatible with the operational results. That is, we will show that anyonic behavior is a result of the topology of the space in two dimensions [7], and does not depend on the particles being identical; but that nevertheless, if the particles are identical, the resulting system is still anyonic.

  12. Universal formalism of Fano resonance

    SciTech Connect

    Huang, Liang; Lai, Ying-Cheng; Luo, Hong-Gang; Grebogi, Celso

    2015-01-15

    The phenomenon of Fano resonance is ubiquitous in a large variety of wave scattering systems, where the resonance profile is typically asymmetric. Whether the parameter characterizing the asymmetry should be complex or real is an issue of great experimental interest. Using coherent quantum transport as a paradigm and taking into account of the collective contribution from all available scattering channels, we derive a universal formula for the Fano-resonance profile. We show that our formula bridges naturally the traditional Fano formulas with complex and real asymmetry parameters, indicating that the two types of formulas are fundamentally equivalent (except for an offset). The connection also reveals a clear footprint for the conductance resonance during a dephasing process. Therefore, the emergence of complex asymmetric parameter when fitting with experimental data needs to be properly interpreted. Furthermore, we have provided a theory for the width of the resonance, which relates explicitly the width to the degree of localization of the close-by eigenstates and the corresponding coupling matrices or the self-energies caused by the leads. Our work not only resolves the issue about the nature of the asymmetry parameter, but also provides deeper physical insights into the origin of Fano resonance. Since the only assumption in our treatment is that the transport can be described by the Green’s function formalism, our results are also valid for broad disciplines including scattering problems of electromagnetic waves, acoustics, and seismology.

  13. Towards a formal semantics for Ada 9X

    NASA Technical Reports Server (NTRS)

    Guaspari, David; Mchugh, John; Wolfgang, Polak; Saaltink, Mark

    1995-01-01

    The Ada 9X language precision team was formed during the revisions of Ada 83, with the goal of analyzing the proposed design, identifying problems, and suggesting improvements, through the use of mathematical models. This report defines a framework for formally describing Ada 9X, based on Kahn's 'natural semantics', and applies the framework to portions of the language. The proposals for exceptions and optimization freedoms are also analyzed, using a different technique.

  14. An Evaluation of Non-Formal Education in Ecuador. Volume 4: Appendices. Final Report.

    ERIC Educational Resources Information Center

    Laosa, Luis M.; And Others

    As the final volume in a 4-volume evaluation report on the University of Massachusetts Non-Formal Education Project (UMass NFEP) initiated in rural Ecuador in 1973, this volume presents appendices to volumes I-III. Appendix A includes the following items: (1) Community Demographic Profile; (2) Description of Introduction to the Community; (3)…

  15. Equations of motion for rotating finite bodies in the extended PPN formalism. [Parametrized Post-Newtonian formalism

    NASA Technical Reports Server (NTRS)

    Dallas, S. S.

    1977-01-01

    The equations of motion for rotating finite bodies are computed in the perfect fluid metric in the extended parametric post-Newtonian (PPN) formalism of Will and Nordtvedt (1972) and are used to build a model of the solar system consisting of N oblate, homogeneous, stationary, self-gravitating masses of rotating perfect fluid. These equations contain relativistic acceleration terms which are currently observable or may be observable in the future with improved radio and laser ranging techniques.

  16. Formal language constrained path problems

    SciTech Connect

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvable efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.

  17. Handbook of Forecasting Techniques. Part 2. Description of 31 Techniques

    DTIC Science & Technology

    1977-08-01

    failure torminnl nodes. The state of the project at each nodu Is specified and the expected profit, cash flow, and probability that the brunch will be taken...theories of psychological growth (Maslow, Graves, etc,), images (Polak, Boulding, Markley, etc.), myths (Campbell), life ways (Morris, Mitchell), and so...invented by market analysts to indicate the general area of correlating psychological factors with consumer behavior. The rationale underlying the use of

  18. Structuring the formal definition of Ada

    NASA Technical Reports Server (NTRS)

    Hansen, Kurt W.

    1986-01-01

    The structure of the formal definition of Ada are described. At present, a difficult subset of Ada has been defined and the experience gained so far by this work is reported. Currently, the work continues towards the formal definition of the Ada language.

  19. 18 CFR 1b.5 - Formal investigations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....

  20. 18 CFR 1b.5 - Formal investigations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....

  1. Formal Moral Education and Individual Moral Development.

    ERIC Educational Resources Information Center

    Friend, Gary Gene

    This report provides a summarization of a study designed to determine if there is a significant relationship between formal religious education and the moral judgment development of college students, and after controlling for formal religious education, to see if there was also a significant relationship between the educational environment or…

  2. 18 CFR 1b.5 - Formal investigations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....

  3. 18 CFR 1b.5 - Formal investigations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....

  4. 18 CFR 1b.5 - Formal investigations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Formal investigations. 1b.5 Section 1b.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.5 Formal investigations....

  5. The Hierarchical Structure of Formal Operational Tasks.

    ERIC Educational Resources Information Center

    Bart, William M.; Mertens, Donna M.

    1979-01-01

    The hierarchical structure of the formal operational period of Piaget's theory of cognitive development was explored through the application of ordering theoretical methods to a set of data that systematically utilized the various formal operational schemes. Results suggested a common structure underlying task performance. (Author/BH)

  6. Integrating Formal and Informal Learning at Work

    ERIC Educational Resources Information Center

    Svensson, Lennart; Ellstrom, Per-Erik; Aberg, Carina

    2004-01-01

    A model for workplace learning is presented, which intends to integrate formal and informal learning with the use of e-learning. An important underlying assumption is that the integration of formal and informal learning is necessary in order to create desirable competencies, from both an individual and an organisational perspective. Two case…

  7. Formal hardware verification of digital circuits

    NASA Technical Reports Server (NTRS)

    Joyce, J.; Seger, C.-J.

    1991-01-01

    The use of formal methods to verify the correctness of digital circuits is less constrained by the growing complexity of digital circuits than conventional methods based on exhaustive simulation. This paper briefly outlines three main approaches to formal hardware verification: symbolic simulation, state machine analysis, and theorem-proving.

  8. Multiverse in the Third Quantized Formalism

    NASA Astrophysics Data System (ADS)

    Mir, Faizal

    2014-11-01

    In this paper we will analyze the third quantization of gravity in path integral formalism. We will use the time-dependent version of Wheeler—DeWitt equation to analyze the multiverse in this formalism. We will propose a mechanism for baryogenesis to occur in the multiverse, without violating the baryon number conservation.

  9. Male-Female Differences in Formal Thought.

    ERIC Educational Resources Information Center

    Linn, Marcia C.

    Two studies were conducted to clarify the influence of experiences and aptitudes on male-female differences in formal thought. Participants were 788 seventh-, ninth-, and eleventh-graders in three school districts differing in location, socioeconomic composition, and course offerings. Formal thought was measured with tasks involving proportional…

  10. A Formal Investigation of Human Spatial Control Skills: Mathematical Formalization, Skill Development, and Skill Assessment

    NASA Astrophysics Data System (ADS)

    Li, Bin

    Spatial control behaviors account for a large proportion of human everyday activities from normal daily tasks, such as reaching for objects, to specialized tasks, such as driving, surgery, or operating equipment. These behaviors involve intensive interactions within internal processes (i.e. cognitive, perceptual, and motor control) and with the physical world. This dissertation builds on a concept of interaction pattern and a hierarchical functional model. Interaction pattern represents a type of behavior synergy that humans coordinates cognitive, perceptual, and motor control processes. It contributes to the construction of the hierarchical functional model that delineates humans spatial control behaviors as the coordination of three functional subsystems: planning, guidance, and tracking/pursuit. This dissertation formalizes and validates these two theories and extends them for the investigation of human spatial control skills encompassing development and assessment. Specifically, this dissertation first presents an overview of studies in human spatial control skills encompassing definition, characteristic, development, and assessment, to provide theoretical evidence for the concept of interaction pattern and the hierarchical functional model. The following, the human experiments for collecting motion and gaze data and techniques to register and classify gaze data, are described. This dissertation then elaborates and mathematically formalizes the hierarchical functional model and the concept of interaction pattern. These theories then enables the construction of a succinct simulation model that can reproduce a variety of human performance with a minimal set of hypotheses. This validates the hierarchical functional model as a normative framework for interpreting human spatial control behaviors. The dissertation then investigates human skill development and captures the emergence of interaction pattern. The final part of the dissertation applies the hierarchical

  11. Image matching with the use of the minimum description length approach

    NASA Astrophysics Data System (ADS)

    Potapov, Alexey S.

    2004-09-01

    Last years we reported at the SPIE conferences the results of development of a hierarchical structural classifier which used the contour structural elements as an input and was designed for matching the aerospace photographs taken in different seasons from different view points, or formed by different kinds of sensors. The aim of this investigation was development of a theoretical approach which could explain the previously described empirical results and could give a proof for the techniques applied in the elaborated algorithms, since many of these techniques were borrowed from the human vision system or were introduced heuristically. The proposed approach is based on the information theory and minimum description length principle (MDL). This principle can be stated in the following way. Such a model of the initial data should be chosen, which gives their shortest description without information losses when the chosen data model is extended with the description of discrepancy between the model and the data or with the description of the random component. In our case the data is a pair of images to be registered. In the task of image matching the images models are extended with the model of their mutual spatial transformation, and such the transformation is chosen which permits to minimize the joint description of a pair of images. To apply the MDL principle the model is introduced which formalizes the image structural description used in the classifier. Consequently, the methods developed earlier were reformulated in the terms of the proposed theoretical approach. As a result, the necessary improvements of the structural classifier were determined which can increase its reliability.

  12. Properties of a Formal Method for Prediction of Emergent Behaviors in Swarm-based Systems

    NASA Technical Reports Server (NTRS)

    Rouff, Christopher; Vanderbilt, Amy; Hinchey, Mike; Truszkowski, Walt; Rash, James

    2004-01-01

    Autonomous intelligent swarms of satellites are being proposed for NASA missions that have complex behaviors and interactions. The emergent properties of swarms make these missions powerful, but at the same time more difficult to design and assure that proper behaviors will emerge. This paper gives the results of research into formal methods techniques for verification and validation of NASA swarm-based missions. Multiple formal methods were evaluated to determine their effectiveness in modeling and assuring the behavior of swarms of spacecraft. The NASA ANTS mission was used as an example of swarm intelligence for which to apply the formal methods. This paper will give the evaluation of these formal methods and give partial specifications of the ANTS mission using four selected methods. We then give an evaluation of the methods and the needed properties of a formal method for effective specification and prediction of emergent behavior in swarm-based systems.

  13. Formal Requirements-Based Programming for Complex Systems

    NASA Technical Reports Server (NTRS)

    Rash, James L.; Hinchey, Michael G.; Rouff, Christopher A.; Gracanin, Denis

    2005-01-01

    Computer science as a field has not yet produced a general method to mechanically transform complex computer system requirements into a provably equivalent implementation. Such a method would be one major step towards dealing with complexity in computing, yet it remains the elusive holy grail of system development. Currently available tools and methods that start with a formal model of a system and mechanically produce a provably equivalent implementation are valuable but not sufficient. The gap that such tools and methods leave unfilled is that the formal models cannot be proven to be equivalent to the system requirements as originated by the customer For the classes of complex systems whose behavior can be described as a finite (but significant) set of scenarios, we offer a method for mechanically transforming requirements (expressed in restricted natural language, or appropriate graphical notations) into a provably equivalent formal model that can be used as the basis for code generation and other transformations. While other techniques are available, this method is unique in offering full mathematical tractability while using notations and techniques that are well known and well trusted. We illustrate the application of the method to an example procedure from the Hubble Robotic Servicing Mission currently under study and preliminary formulation at NASA Goddard Space Flight Center.

  14. From Livingstone to SMV: Formal Verification for Autonomous Spacecrafts

    NASA Technical Reports Server (NTRS)

    Pecheur, Charles; Simmons, Reid

    2000-01-01

    To fulfill the needs of its deep space exploration program, NASA is actively supporting research and development in autonomy software. However, the reliable and cost-effective development and validation of autonomy systems poses a tough challenge. Traditional scenario-based testing methods fall short because of the combinatorial explosion of possible situations to be analyzed, and formal verification techniques typically require a tedious, manual modelling by formal method experts. This paper presents the application of formal verification techniques in the development of autonomous controllers based on Livingstone, a model-based health-monitoring system that can detect and diagnose anomalies and suggest possible recovery actions. We present a translator that converts the models used by Livingstone into specifications that can be verified with the SMV model checker. The translation frees the Livingstone developer from the tedious conversion of his design to SMV, and isolates him from the technical details of the SMV program. We describe different aspects of the translation and briefly discuss its application to several NASA domains.

  15. A Formal Methods Approach to the Analysis of Mode Confusion

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Miller, Steven P.; Potts, James N.; Carreno, Victor A.

    2004-01-01

    The goal of the new NASA Aviation Safety Program (AvSP) is to reduce the civil aviation fatal accident rate by 80% in ten years and 90% in twenty years. This program is being driven by the accident data with a focus on the most recent history. Pilot error is the most commonly cited cause for fatal accidents (up to 70%) and obviously must be given major consideration in this program. While the greatest source of pilot error is the loss of situation awareness , mode confusion is increasingly becoming a major contributor as well. The January 30, 1995 issue of Aviation Week lists 184 incidents and accidents involving mode awareness including the Bangalore A320 crash 2/14/90, the Strasbourg A320 crash 1/20/92, the Mulhouse-Habsheim A320 crash 6/26/88, and the Toulouse A330 crash 6/30/94. These incidents and accidents reveal that pilots sometimes become confused about what the cockpit automation is doing. Consequently, human factors research is an obvious investment area. However, even a cursory look at the accident data reveals that the mode confusion problem is much deeper than just training deficiencies and a lack of human-oriented design. This is readily acknowledged by human factors experts. It seems that further progress in human factors must come through a deeper scrutiny of the internals of the automation. It is in this arena that formal methods can contribute. Formal methods refers to the use of techniques from logic and discrete mathematics in the specification, design, and verification of computer systems, both hardware and software. The fundamental goal of formal methods is to capture requirements, designs and implementations in a mathematically based model that can be analyzed in a rigorous manner. Research in formal methods is aimed at automating this analysis as much as possible. By capturing the internal behavior of a flight deck in a rigorous and detailed formal model, the dark corners of a design can be analyzed. This paper will explore how formal

  16. Covariant Quantisation in the Antifield Formalism

    NASA Astrophysics Data System (ADS)

    Vandoren, S.

    1996-01-01

    In this thesis we give an overview of the antifield formalism and show how it must be used to quantise arbitrary gauge theories. The formalism is further developed and illustrated in several examples, including Yang-Mills theory, chiral W_3 and W_{2,5/2} gravity, strings in curved backgrounds and topological field theories. All these models are characterised by their gauge algebra, which can be open, reducible, or even infinitly reducible. We show in detail how to perform the gauge fixing and how to compute the anomalies using Pauli-Villars regularisation and the heat kernel method. Finally, we discuss the geometrical structure of the antifield formalism.

  17. Formal Methods for Automated Diagnosis of Autosub 6000

    NASA Technical Reports Server (NTRS)

    Ernits, Juhan; Dearden, Richard; Pebody, Miles

    2009-01-01

    This is a progress report on applying formal methods in the context of building an automated diagnosis and recovery system for Autosub 6000, an Autonomous Underwater Vehicle (AUV). The diagnosis task involves building abstract models of the control system of the AUV. The diagnosis engine is based on Livingstone 2, a model-based diagnoser originally built for aerospace applications. Large parts of the diagnosis model can be built without concrete knowledge about each mission, but actual mission scripts and configuration parameters that carry important information for diagnosis are changed for every mission. Thus we use formal methods for generating the mission control part of the diagnosis model automatically from the mission script and perform a number of invariant checks to validate the configuration. After the diagnosis model is augmented with the generated mission control component model, it needs to be validated using verification techniques.

  18. Application of Lightweight Formal Methods to Software Security

    NASA Technical Reports Server (NTRS)

    Gilliam, David P.; Powell, John D.; Bishop, Matt

    2005-01-01

    Formal specification and verification of security has proven a challenging task. There is no single method that has proven feasible. Instead, an integrated approach which combines several formal techniques can increase the confidence in the verification of software security properties. Such an approach which species security properties in a library that can be reused by 2 instruments and their methodologies developed for the National Aeronautics and Space Administration (NASA) at the Jet Propulsion Laboratory (JPL) are described herein The Flexible Modeling Framework (FMF) is a model based verijkation instrument that uses Promela and the SPIN model checker. The Property Based Tester (PBT) uses TASPEC and a Text Execution Monitor (TEM). They are used to reduce vulnerabilities and unwanted exposures in software during the development and maintenance life cycles.

  19. Green's function formalism for calculating spin-wave spectra

    NASA Astrophysics Data System (ADS)

    Aryasetiawan, F.; Karlsson, K.

    1999-09-01

    We propose a formalism for calculating ab initio spin-wave spectra which is based on the many-body temperature Green's function. The main quantity to be calculated is the linear magnetic susceptibility from which all magnetic excitations involving the creation of an additional spin in the system can formally be obtained. The Schwinger functional derivative technique is employed in calculating the self-energy. The approach avoids both the assumption of local spins (Heisenberg model) and the use of a local exchange and correlation interaction (local-density approximation). Starting from the GW approximation we obtain a Bethe-Salpeter equation for the kernel describing the interaction between electrons in both spin channels. However, this kernel exhibits a nonlocal screened interaction.

  20. On the Formal Verification of Conflict Detection Algorithms

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar; Butler, Ricky W.; Carreno, Victor A.; Dowek, Gilles

    2001-01-01

    Safety assessment of new air traffic management systems is a main issue for civil aviation authorities. Standard techniques such as testing and simulation have serious limitations in new systems that are significantly more autonomous than the older ones. In this paper, we present an innovative approach, based on formal verification, for establishing the correctness of conflict detection systems. Fundamental to our approach is the concept of trajectory, which is a continuous path in the x-y plane constrained by physical laws and operational requirements. From the Model of trajectories, we extract, and formally prove, high level properties that can serve as a framework to analyze conflict scenarios. We use the Airborne Information for Lateral Spacing (AILS) alerting algorithm as a case study of our approach.

  1. Petri Nets - A Mathematical Formalism to Analyze Chemical Reaction Networks.

    PubMed

    Koch, Ina

    2010-12-17

    In this review we introduce and discuss Petri nets - a mathematical formalism to describe and analyze chemical reaction networks. Petri nets were developed to describe concurrency in general systems. We find most applications to technical and financial systems, but since about twenty years also in systems biology to model biochemical systems. This review aims to give a short informal introduction to the basic formalism illustrated by a chemical example, and to discuss possible applications to the analysis of chemical reaction networks, including cheminformatics. We give a short overview about qualitative as well as quantitative modeling Petri net techniques useful in systems biology, summarizing the state-of-the-art in that field and providing the main literature references. Finally, we discuss advantages and limitations of Petri nets and give an outlook to further development.

  2. Langevin description of nonequilibrium quantum fields

    NASA Astrophysics Data System (ADS)

    Gautier, F.; Serreau, J.

    2012-12-01

    We consider the nonequilibrium dynamics of a real quantum scalar field. We show the formal equivalence of the exact evolution equations for the statistical and spectral two-point functions with a fictitious Langevin process and examine the conditions under which a local Markovian dynamics is a valid approximation. In quantum field theory, the memory kernel and the noise correlator typically exhibit long time power laws and are thus highly nonlocal, thereby questioning the possibility of a local description. We show that despite this fact, there is a finite time range during which a local description is accurate. This requires the theory to be (effectively) weakly coupled. We illustrate the use of such a local description for studies of decoherence and entropy production in quantum field theory.

  3. Importance of Reversibility in the Quantum Formalism

    NASA Astrophysics Data System (ADS)

    David, François

    2011-10-01

    In this Letter I stress the role of causal reversibility (time symmetry), together with causality and locality, in the justification of the quantum formalism. First, in the algebraic quantum formalism, I show that the assumption of reversibility implies that the observables of a quantum theory form an abstract real C⋆ algebra, and can be represented as an algebra of operators on a real Hilbert space. Second, in the quantum logic formalism, I emphasize which axioms for the lattice of propositions (the existence of an orthocomplementation and the covering property) derive from reversibility. A new argument based on locality and Soler’s theorem is used to derive the representation as projectors on a regular Hilbert space from the general quantum logic formalism. In both cases it is recalled that the restriction to complex algebras and Hilbert spaces comes from the constraints of locality and separability.

  4. The adolescent personality, formal reasoning, and values.

    PubMed

    Darmody, J P

    1991-01-01

    This study examined the relationship between levels of Piagetian formal reasoning ability and values preferences derived from the Rokeach Value Survey. The subjects were 448 secondary school students (mean age = 16.25 years). The results of the study were consistent with predictions about the likely changes in value rankings as formal reasoning ability develops. Subjects with high scores on formal reasoning ranked terminal values representing abstract notions with long-term implications higher than those focusing on immediate gratification. They also favored the instrumental values of self-reliance, competence, and independence. Low scorers on formal reasoning showed a preference for value groupings which were personal, hedonistic, and involved immediate gratification and social approval.

  5. Formal specification of human-computer interfaces

    NASA Technical Reports Server (NTRS)

    Auernheimer, Brent

    1990-01-01

    A high-level formal specification of a human computer interface is described. Previous work is reviewed and the ASLAN specification language is described. Top-level specifications written in ASLAN for a library and a multiwindow interface are discussed.

  6. Importance of reversibility in the quantum formalism.

    PubMed

    David, François

    2011-10-28

    In this Letter I stress the role of causal reversibility (time symmetry), together with causality and locality, in the justification of the quantum formalism. First, in the algebraic quantum formalism, I show that the assumption of reversibility implies that the observables of a quantum theory form an abstract real C^{⋆} algebra, and can be represented as an algebra of operators on a real Hilbert space. Second, in the quantum logic formalism, I emphasize which axioms for the lattice of propositions (the existence of an orthocomplementation and the covering property) derive from reversibility. A new argument based on locality and Soler's theorem is used to derive the representation as projectors on a regular Hilbert space from the general quantum logic formalism. In both cases it is recalled that the restriction to complex algebras and Hilbert spaces comes from the constraints of locality and separability.

  7. General formalism for singly thermostated Hamiltonian dynamics.

    PubMed

    Ramshaw, John D

    2015-11-01

    A general formalism is developed for constructing modified Hamiltonian dynamical systems which preserve a canonical equilibrium distribution by adding a time evolution equation for a single additional thermostat variable. When such systems are ergodic, canonical ensemble averages can be computed as dynamical time averages over a single trajectory. Systems of this type were unknown until their recent discovery by Hoover and colleagues. The present formalism should facilitate the discovery, construction, and classification of other such systems by encompassing a wide class of them within a single unified framework. This formalism includes both canonical and generalized Hamiltonian systems in a state space of arbitrary dimensionality (either even or odd) and therefore encompasses both few- and many-particle systems. Particular attention is devoted to the physical motivation and interpretation of the formalism, which largely determine its structure. An analogy to stochastic thermostats and fluctuation-dissipation theorems is briefly discussed.

  8. Transitions from Formal Education to the Workplace

    ERIC Educational Resources Information Center

    Olson, Joann S.

    2014-01-01

    This chapter frames the transition to adulthood in the context of the moving from formal educational settings to the often less-structured learning that occurs in workplace settings. Although schooling may end, learning continues.

  9. Why Engineers Should Consider Formal Methods

    NASA Technical Reports Server (NTRS)

    Holloway, C. Michael

    1997-01-01

    This paper presents a logical analysis of a typical argument favoring the use of formal methods for software development, and suggests an alternative argument that is simpler and stronger than the typical one.

  10. Experiences Using Formal Methods for Requirements Modeling

    NASA Technical Reports Server (NTRS)

    Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David

    1996-01-01

    This paper describes three cases studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, the formal modeling provided a cost effective enhancement of the existing verification and validation processes. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.

  11. A Survey of Formal Methods for Intelligent Swarms

    NASA Technical Reports Server (NTRS)

    Truszkowski, Walt; Rash, James; Hinchey, Mike; Rouff, Chrustopher A.

    2004-01-01

    cutting edge in system correctness, and requires higher levels of assurance than other (traditional) missions that use a single or small number of spacecraft that are deterministic in nature and have near continuous communication access. One of the highest possible levels of assurance comes from the application of formal methods. Formal methods are mathematics-based tools and techniques for specifying and verifying (software and hardware) systems. They are particularly useful for specifying complex parallel systems, such as exemplified by the ANTS mission, where the entire system is difficult for a single person to fully understand, a problem that is multiplied with multiple developers. Once written, a formal specification can be used to prove properties of a system (e.g., the underlying system will go from one state to another or not into a specific state) and check for particular types of errors (e.g., race or livelock conditions). A formal specification can also be used as input to a model checker for further validation. This report gives the results of a survey of formal methods techniques for verification and validation of space missions that use swarm technology. Multiple formal methods were evaluated to determine their effectiveness in modeling and assuring the behavior of swarms of spacecraft using the ANTS mission as an example system. This report is the first result of the project to determine formal approaches that are promising for formally specifying swarm-based systems. From this survey, the most promising approaches were selected and are discussed relative to their possible application to the ANTS mission. Future work will include the application of an integrated approach, based on the selected approaches identified in this report, to the formal specification of the ANTS mission.

  12. Design for validation, based on formal methods

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    1990-01-01

    Validation of ultra-reliable systems decomposes into two subproblems: (1) quantification of probability of system failure due to physical failure; (2) establishing that Design Errors are not present. Methods of design, testing, and analysis of ultra-reliable software are discussed. It is concluded that a design-for-validation based on formal methods is needed for the digital flight control systems problem, and also that formal methods will play a major role in the development of future high reliability digital systems.

  13. Report on the formal specification and partial verification of the VIPER microprocessor

    NASA Technical Reports Server (NTRS)

    Brock, Bishop; Hunt, Warren A., Jr.

    1991-01-01

    The formal specification and partial verification of the VIPER microprocessor is reviewed. The VIPER microprocessor was designed by RSRE, Malvern, England, for safety critical computing applications (e.g., aircraft, reactor control, medical instruments, armaments). The VIPER was carefully specified and partially verified in an attempt to provide a microprocessor with completely predictable operating characteristics. The specification of VIPER is divided into several levels of abstraction, from a gate-level description up to an instruction execution model. Although the consistency between certain levels was demonstrated with mechanically-assisted mathematical proof, the formal verification of VIPER was never completed.

  14. Interval Predictor Models with a Formal Characterization of Uncertainty and Reliability

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Giesy, Daniel P.; Kenny, Sean P.

    2014-01-01

    This paper develops techniques for constructing empirical predictor models based on observations. By contrast to standard models, which yield a single predicted output at each value of the model's inputs, Interval Predictors Models (IPM) yield an interval into which the unobserved output is predicted to fall. The IPMs proposed prescribe the output as an interval valued function of the model's inputs, render a formal description of both the uncertainty in the model's parameters and of the spread in the predicted output. Uncertainty is prescribed as a hyper-rectangular set in the space of model's parameters. The propagation of this set through the empirical model yields a range of outputs of minimal spread containing all (or, depending on the formulation, most) of the observations. Optimization-based strategies for calculating IPMs and eliminating the effects of outliers are proposed. Outliers are identified by evaluating the extent by which they degrade the tightness of the prediction. This evaluation can be carried out while the IPM is calculated. When the data satisfies mild stochastic assumptions, and the optimization program used for calculating the IPM is convex (or, when its solution coincides with the solution to an auxiliary convex program), the model's reliability (that is, the probability that a future observation would be within the predicted range of outputs) can be bounded rigorously by a non-asymptotic formula.

  15. Optical simulation of photovoltaic modules with multiple textured interfaces using the matrix-based formalism OPTOS.

    PubMed

    Tucher, Nico; Eisenlohr, Johannes; Gebrewold, Habtamu; Kiefel, Peter; Höhn, Oliver; Hauser, Hubert; Goldschmidt, Jan Christoph; Bläsi, Benedikt

    2016-07-11

    The OPTOS formalism is a matrix-based approach to determine the optical properties of textured optical sheets. It is extended within this work to enable the modelling of systems with an arbitrary number of textured, plane-parallel interfaces. A matrix-based system description is derived that accounts for the optical reflection and transmission interaction between all textured interfaces. Using OPTOS, we calculate reflectance and absorptance of complete photovoltaic module stacks, which consist of encapsulated silicon solar cells featuring textures that operate in different optical regimes. As exemplary systems, solar cells with and without module encapsulation are shown to exhibit a considerable absorptance gain if the random pyramid front side texture is combined with a diffractive rear side grating. A variation of the sunlight's angle of incidence reveals that the grating gain is almost not affected for incoming polar angles up to 60°. Considering as well the good agreement with alternative simulation techniques, OPTOS is demonstrated to be a versatile and efficient method for the optical analysis of photovoltaic modules.

  16. Properties of a Formal Method to Model Emergence in Swarm-Based Systems

    NASA Technical Reports Server (NTRS)

    Rouff, Christopher; Vanderbilt, Amy; Truszkowski, Walt; Rash, James; Hinchey, Mike

    2004-01-01

    Future space missions will require cooperation between multiple satellites and/or rovers. Developers are proposing intelligent autonomous swarms for these missions, but swarm-based systems are difficult or impossible to test with current techniques. This viewgraph presentation examines the use of formal methods in testing swarm-based systems. The potential usefulness of formal methods in modeling the ANTS asteroid encounter mission is also examined.

  17. Electrical stimulation therapy for dysphagia: descriptive results of two surveys.

    PubMed

    Crary, Michael A; Carnaby-Mann, Giselle D; Faunce, Allison

    2007-07-01

    Given the paucity of objective information on neuromuscular electrical stimulation approaches to dysphagia therapy, and the expanding utilization of this clinical approach, we designed and conducted two surveys to gather large-scale information regarding reported practice patterns, outcomes, complications, and professional perceptions associated with electrical stimulation approaches to dysphagia therapy. Self-administered questionnaires were mailed to 1000 randomly selected speech-language pathologists in each of two groups: (1) clinicians who had completed a formal electrical stimulation training course and were actively using these techniques, and (2) clinicians who were members of Special Interest Division 13 of the American Speech-Language and Hearing Association. Survey responses were anonymous and no incentive to respond was included. Acceptable response rates were achieved for both surveys (47% and 48%). Both groups of respondents were demographically similar and reported similar practice patterns. Stroke was the most common etiology of dysphagia treated with this approach. The majority of respondents identified no specific dysphagia criteria for application of electrical stimulation, used varied behavioral treatment methods, and did not follow patients beyond therapy. Clinicians reported positive outcomes with no treatment-related complications. Satisfaction with this approach was reported to be high among patients and professionals. Clinicians who did not report using these techniques indicated that they were waiting for more objective information on clinical outcomes and safety. Results of these surveys form an initial description of practice patterns and outcomes associated with electrical stimulation approaches to dysphagia therapy.

  18. Hamiltonian formalism for semiflexible molecules in Cartesian coordinates.

    PubMed

    Kneller, G R

    2006-09-21

    The article gives a concise description of Hamiltonian dynamics and thermal averages of semiflexible molecules in Cartesian coordinates. Using the concept of constrained inverse matrices introduced by Bott and Duffin [Trans. Am. Math. Soc. 74, 99 (1953)] explicit expressions are derived for the constrained Hamiltonian, the corresponding equations of motion, and the momentum partition function. In this context Fixman-type corrections of constrained configurational averages are derived for different forms of the constraints. It is shown that the use of mass-weighted coordinates leads to a nonbiased sampling of constrained configurational averages in Cartesian coordinates. The formalism allows moreover to define and to calculate effective masses arising in thermal velocity averages of atoms in semiflexible molecules. These effective masses are identical to the corresponding Sachs-Teller recoil masses, which are here generalized to the case of only partially rigid molecules.

  19. An Integrated Environment for Efficient Formal Design and Verification

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The general goal of this project was to improve the practicality of formal methods by combining techniques from model checking and theorem proving. At the time the project was proposed, the model checking and theorem proving communities were applying different tools to similar problems, but there was not much cross-fertilization. This project involved a group from SRI that had substantial experience in the development and application of theorem-proving technology, and a group at Stanford that specialized in model checking techniques. Now, over five years after the proposal was submitted, there are many research groups working on combining theorem-proving and model checking techniques, and much more communication between the model checking and theorem proving research communities. This project contributed significantly to this research trend. The research work under this project covered a variety of topics: new theory and algorithms; prototype tools; verification methodology; and applications to problems in particular domains.

  20. Formal representation of 3D structural geological models

    NASA Astrophysics Data System (ADS)

    Wang, Zhangang; Qu, Honggang; Wu, Zixing; Yang, Hongjun; Du, Qunle

    2016-05-01

    The development and widespread application of geological modeling methods has increased demands for the integration and sharing services of three dimensional (3D) geological data. However, theoretical research in the field of geological information sciences is limited despite the widespread use of Geographic Information Systems (GIS) in geology. In particular, fundamental research on the formal representations and standardized spatial descriptions of 3D structural models is required. This is necessary for accurate understanding and further applications of geological data in 3D space. In this paper, we propose a formal representation method for 3D structural models using the theory of point set topology, which produces a mathematical definition for the major types of geological objects. The spatial relationships between geologic boundaries, structures, and units are explained in detail using the 9-intersection model. Reasonable conditions for describing the topological space of 3D structural models are also provided. The results from this study can be used as potential support for the standardized representation and spatial quality evaluation of 3D structural models, as well as for specific needs related to model-based management, query, and analysis.

  1. Formalization and web-based implementation of spatial data fusion

    NASA Astrophysics Data System (ADS)

    Wiemann, Stefan

    2017-02-01

    Spatial data fusion plays an important role for spatial information retrieval from disconnected data sources and is thus a precondition for comprehensive and consistent decision making. In particular on the Web, it can help to combine spatial data from the variety of existing, but distributed sources, e.g. as provided by Spatial Data Infrastructure (SDI). However, standardized spatial data processing on the Web still lacks broad acceptance beyond the scientific domain. This article describes a formalization and service-based implementation of the spatial data fusion process. The formalization builds on a set theoretic description of the considered domain and derives a number of possible fusion objectives. Geoprocessing patterns are used to describe commonly used sub-routines of the fusion process and therefore support the workflow composition. The implementation is based on open standards and comprises a Web-client, several geoprocessing services and a fusion engine to support the Web-based compilation and execution of spatial data fusion workflows in an ad hoc manner.

  2. Strengths and limitations of formal ontologies in the biomedical domain

    PubMed Central

    Schulz, Stefan; Stenzhorn, Holger; Boeker, Martin; Smith, Barry

    2010-01-01

    We propose a typology of representational artifacts for health care and life sciences domains and associate this typology with different kinds of formal ontology and logic, drawing conclusions as to the strengths and limitations for ontology of different kinds of logical resources, with a focus on description logics. The four types of domain representation we consider are: (i) lexico-semantic representation, (ii) representation of types of entities, (iii) representations of background knowledge, and (iv) representation of individuals. We advocate a clear distinction of the four kinds of representation in order to provide a more rational basis for using of ontologies and related artifacts to advance integration of data and interoperability of associated reasoning systems. We highlight the fact that only a minor portion of scientifically relevant facts in a domain such as biomedicine can be adequately represented by formal ontologies when the latter are conceived as representations of entity types. In particular, the attempt to encode default or probabilistic knowledge using ontologies so conceived is prone to produce unintended, erroneous models. PMID:20640238

  3. Developing Formal Correctness Properties from Natural Language Requirements

    NASA Technical Reports Server (NTRS)

    Nikora, Allen P.

    2006-01-01

    This viewgraph presentation reviews the rationale of the program to transform natural language specifications into formal notation.Specifically, automate generation of Linear Temporal Logic (LTL)correctness properties from natural language temporal specifications. There are several reasons for this approach (1) Model-based techniques becoming more widely accepted, (2) Analytical verification techniques (e.g., model checking, theorem proving) significantly more effective at detecting types of specification design errors (e.g., race conditions, deadlock) than manual inspection, (3) Many requirements still written in natural language, which results in a high learning curve for specification languages, associated tools and increased schedule and budget pressure on projects reduce training opportunities for engineers, and (4) Formulation of correctness properties for system models can be a difficult problem. This has relevance to NASA in that it would simplify development of formal correctness properties, lead to more widespread use of model-based specification, design techniques, assist in earlier identification of defects and reduce residual defect content for space mission software systems. The presentation also discusses: potential applications, accomplishments and/or technological transfer potential and the next steps.

  4. Formal Methods for Cryptographic Protocol Analysis: Emerging Issues and Trends

    DTIC Science & Technology

    2003-01-01

    6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Research Laboratory...Ferguson and Schneier [27] found an attack in which an intruder could trick an initiator into agreeing on the wrong SA by making use of the fact that...of some the techniques used for this last). The trick now, of course, is to integrate the formal analysis into the standard- ization process. With the

  5. Formal Verification for a Next-Generation Space Shuttle

    NASA Technical Reports Server (NTRS)

    Nelson, Stacy D.; Pecheur, Charles; Koga, Dennis (Technical Monitor)

    2002-01-01

    This paper discusses the verification and validation (V&2) of advanced software used for integrated vehicle health monitoring (IVHM), in the context of NASA's next-generation space shuttle. We survey the current VBCV practice and standards used in selected NASA projects, review applicable formal verification techniques, and discuss their integration info existing development practice and standards. We also describe two verification tools, JMPL2SMV and Livingstone PathFinder, that can be used to thoroughly verify diagnosis applications that use model-based reasoning, such as the Livingstone system.

  6. Formalization Studies in Functional Size Measurement: How Do They Help?

    NASA Astrophysics Data System (ADS)

    Ozkan, Baris; Demirors, Onur

    Functional size has been favored as a software characteristic that can be measured early and independent of language, tools, techniques and technology; hence has many uses in software project management. It has been about three decades since Albrecht introduced the concept of functional size. However, Functional Size Measurement (FSM) has not been a common practice in the software community. The problems with FSM method structures and practices have been discussed to be the major factors to explain this situation. In this paper, we make a review of formalization proposals to the problems in Functional Size Measurement (FSM). We analyze the works included in the papers and we explore the extent of their contributions.

  7. A Survey of Logic Formalisms to Support Mishap Analysis

    NASA Technical Reports Server (NTRS)

    Johnson, Chris; Holloway, C. M.

    2003-01-01

    Mishap investigations provide important information about adverse events and near miss incidents. They are intended to help avoid any recurrence of previous failures. Over time, they can also yield statistical information about incident frequencies that helps to detect patterns of failure and can validate risk assessments. However, the increasing complexity of many safety critical systems is posing new challenges for mishap analysis. Similarly, the recognition that many failures have complex, systemic causes has helped to widen the scope of many mishap investigations. These two factors have combined to pose new challenges for the analysis of adverse events. A new generation of formal and semi-formal techniques have been proposed to help investigators address these problems. We introduce the term mishap logics to collectively describe these notations that might be applied to support the analysis of mishaps. The proponents of these notations have argued that they can be used to formally prove that certain events created the necessary and sufficient causes for a mishap to occur. These proofs can be used to reduce the bias that is often perceived to effect the interpretation of adverse events. Others have argued that one cannot use logic formalisms to prove causes in the same way that one might prove propositions or theorems. Such mechanisms cannot accurately capture the wealth of inductive, deductive and statistical forms of inference that investigators must use in their analysis of adverse events. This paper provides an overview of these mishap logics. It also identifies several additional classes of logic that might also be used to support mishap analysis.

  8. Baxter Operator Formalism for Macdonald Polynomials

    NASA Astrophysics Data System (ADS)

    Gerasimov, Anton; Lebedev, Dimitri; Oblezin, Sergey

    2013-11-01

    We develop basic constructions of the Baxter operator formalism for the Macdonald polynomials associated with root systems of type A. Precisely, we construct a bispectral pair of mutually commuting Baxter operators such that the Macdonald polynomials are their common eigenfunctions. The bispectral pair of Baxter operators is closely related to the bispectral pair of recursive operators for Macdonald polynomials leading to various families of their integral representations. We also construct the Baxter operator formalism for the q-deformed {{gl}_{ell+1}} -Whittaker functions and the Jack polynomials obtained by degenerations of the Macdonald polynomials associated with the type A ℓ root system. This note provides a generalization of our previous results on the Baxter operator formalism for the Whittaker functions. It was demonstrated previously that Baxter operator formalism for the Whittaker functions has deep connections with representation theory. In particular, the Baxter operators should be considered as elements of appropriate spherical Hecke algebras and their eigenvalues are identified with local Archimedean L-factors associated with admissible representations of reductive groups over {{R}}. We expect that the Baxter operator formalism for the Macdonald polynomials has an interpretation in representation theory over higher-dimensional local/global fields.

  9. Formal Methods Case Studies for DO-333

    NASA Technical Reports Server (NTRS)

    Cofer, Darren; Miller, Steven P.

    2014-01-01

    RTCA DO-333, Formal Methods Supplement to DO-178C and DO-278A provides guidance for software developers wishing to use formal methods in the certification of airborne systems and air traffic management systems. The supplement identifies the modifications and additions to DO-178C and DO-278A objectives, activities, and software life cycle data that should be addressed when formal methods are used as part of the software development process. This report presents three case studies describing the use of different classes of formal methods to satisfy certification objectives for a common avionics example - a dual-channel Flight Guidance System. The three case studies illustrate the use of theorem proving, model checking, and abstract interpretation. The material presented is not intended to represent a complete certification effort. Rather, the purpose is to illustrate how formal methods can be used in a realistic avionics software development project, with a focus on the evidence produced that could be used to satisfy the verification objectives found in Section 6 of DO-178C.

  10. Developmental trauma disorder: pros and cons of including formal criteria in the psychiatric diagnostic systems

    PubMed Central

    2013-01-01

    Background This article reviews the current debate on developmental trauma disorder (DTD) with respect to formalizing its diagnostic criteria. Victims of abuse, neglect, and maltreatment in childhood often develop a wide range of age-dependent psychopathologies with various mental comorbidities. The supporters of a formal DTD diagnosis argue that post-traumatic stress disorder (PTSD) does not cover all consequences of severe and complex traumatization in childhood. Discussion Traumatized individuals are difficult to treat, but clinical experience has shown that they tend to benefit from specific trauma therapy. A main argument against inclusion of formal DTD criteria into existing diagnostic systems is that emphasis on the etiology of the disorder might force current diagnostic systems to deviate from their purely descriptive nature. Furthermore, comorbidities and biological aspects of the disorder may be underdiagnosed using the DTD criteria. Summary Here, we discuss arguments for and against the proposal of DTD criteria and address implications and consequences for the clinical practice. PMID:23286319

  11. Simultaneous Measurement of Tracer and Interdiffusion Coefficients: An Isotopic Phenomenological Diffusion Formalism for the Binary Alloy

    SciTech Connect

    Belova, Irina; Kulkarni, Nagraj S; Sohn, Yong Ho; Murch, Prof. Graeme

    2013-01-01

    In this paper, a new development of the classic Onsager phenomenological formalism is derived using relations based on linear response theory. The development concerns the correct description of the fluxes of the atomic isotopes. The resulting expressions in the laboratory frame are surprisingly simple and consist of terms coming from the standard interdiffusion expressions and from Fick s first law where the tracer diffusion coefficient is involved thus providing a better understanding of the relationship between the two approaches - Fick s first law and the Onsager phenomenological formalism. From an experimental application perspective, the new development is applied to the binary alloy case. The formalism provides the means to obtain the interdiffusion coefficient and tracer diffusion coefficients simultaneously from analysis of the interdiffusion concentration profiles in a single experiment.

  12. Formalizing Darwinism and inclusive fitness theory.

    PubMed

    Grafen, Alan

    2009-11-12

    Inclusive fitness maximization is a basic building block for biological contributions to any theory of the evolution of society. There is a view in mathematical population genetics that nothing is caused to be maximized in the process of natural selection, but this is explained as arising from a misunderstanding about the meaning of fitness maximization. Current theoretical work on inclusive fitness is discussed, with emphasis on the author's 'formal Darwinism project'. Generally, favourable conclusions are drawn about the validity of assuming fitness maximization, but the need for continuing work is emphasized, along with the possibility that substantive exceptions may be uncovered. The formal Darwinism project aims more ambitiously to represent in a formal mathematical framework the central point of Darwin's Origin of Species, that the mechanical processes of inheritance and reproduction can give rise to the appearance of design, and it is a fitting ambition in Darwin's bicentenary year to capture his most profound discovery in the lingua franca of science.

  13. Digital Resource Developments for Mathematics Education Involving Homework across Formal, Non-Formal and Informal Settings

    ERIC Educational Resources Information Center

    Radovic, Slaviša; Passey, Don

    2016-01-01

    The aim of this paper is to explore further an under-developed area--how drivers of curriculum, pedagogy and assessment conceptions and practices shape the creation and uses of technologically based resources to support mathematics learning across informal, non-formal and formal learning environments. The paper considers: the importance of…

  14. Enhancing the Intercultural Effectiveness of Exchange Programmes: Formal and Non-Formal Educational Interventions

    ERIC Educational Resources Information Center

    Almeida, Joana; Fantini, Alvino E.; Simões, Ana Raquel; Costa, Nilza

    2016-01-01

    This paper examines how the addition of intercultural interventions carried out throughout European credit-bearing exchange programmes can enhance sojourners' development of intercultural competencies, and it explores how both formal and non-formal pedagogical interventions may be designed and implemented. Such interventions were conducted at a…

  15. Combining Formal, Non-Formal and Informal Learning for Workforce Skill Development

    ERIC Educational Resources Information Center

    Misko, Josie

    2008-01-01

    This literature review, undertaken for Australian Industry Group, shows how multiple variations and combinations of formal, informal and non-formal learning, accompanied by various government incentives and organisational initiatives (including job redesign, cross-skilling, multi-skilling, diversified career pathways, action learning projects,…

  16. About the Identity of Informational Geography for Formal, Non-Formal, and Informal Educational Purposes.

    ERIC Educational Resources Information Center

    Verduin-Muller, Henriette

    In a shrinking world where there is limited space, materials, and capital for men's basic needs, it is important to make well considered use of the physical and human geographical setting. To obtain from the geographical setting the information needed to attain adequate decision making, empirical research is needed, and through formal, non-formal,…

  17. User Interface Technology for Formal Specification Development

    NASA Technical Reports Server (NTRS)

    Lowry, Michael; Philpot, Andrew; Pressburger, Thomas; Underwood, Ian; Lum, Henry, Jr. (Technical Monitor)

    1994-01-01

    Formal specification development and modification are an essential component of the knowledge-based software life cycle. User interface technology is needed to empower end-users to create their own formal specifications. This paper describes the advanced user interface for AMPHION1 a knowledge-based software engineering system that targets scientific subroutine libraries. AMPHION is a generic, domain-independent architecture that is specialized to an application domain through a declarative domain theory. Formal specification development and reuse is made accessible to end-users through an intuitive graphical interface that provides semantic guidance in creating diagrams denoting formal specifications in an application domain. The diagrams also serve to document the specifications. Automatic deductive program synthesis ensures that end-user specifications are correctly implemented. The tables that drive AMPHION's user interface are automatically compiled from a domain theory; portions of the interface can be customized by the end-user. The user interface facilitates formal specification development by hiding syntactic details, such as logical notation. It also turns some of the barriers for end-user specification development associated with strongly typed formal languages into active sources of guidance, without restricting advanced users. The interface is especially suited for specification modification. AMPHION has been applied to the domain of solar system kinematics through the development of a declarative domain theory. Testing over six months with planetary scientists indicates that AMPHION's interactive specification acquisition paradigm enables users to develop, modify, and reuse specifications at least an order of magnitude more rapidly than manual program development.

  18. Extending the ADM formalism to Weyl geometry

    SciTech Connect

    Barreto, A. B.; Almeida, T. S.; Romero, C.

    2015-03-26

    In order to treat quantum cosmology in the framework of Weyl spacetimes we take the first step of extending the Arnowitt-Deser-Misner formalism to Weyl geometry. We then obtain an expression of the curvature tensor in terms of spatial quantities by splitting spacetime in (3+l)-dimensional form. We next write the Lagrangian of the gravitation field based in Weyl-type gravity theory. We extend the general relativistic formalism in such a way that it can be applied to investigate the quantum cosmology of models whose spacetimes are endowed with a Weyl geometrical structure.

  19. Raman Tensor Formalism for Optically Anisotropic Crystals.

    PubMed

    Kranert, Christian; Sturm, Chris; Schmidt-Grund, Rüdiger; Grundmann, Marius

    2016-03-25

    We present a formalism for calculating the Raman scattering intensity dependent on the polarization configuration for optically anisotropic crystals. It can be applied to crystals of arbitrary orientation and crystal symmetry measured in normal incidence backscattering geometry. The classical Raman tensor formalism cannot be used for optically anisotropic materials due to birefringence causing the polarization within the crystal to be depth dependent. We show that in the limit of averaging over a sufficiently large scattering depth, the observed Raman intensities converge and can be described by an effective Raman tensor given here. Full agreement with experimental results for uniaxial and biaxial crystals is demonstrated.

  20. Educación no formal

    NASA Astrophysics Data System (ADS)

    Tignanelli, H.

    Se comentan en esta comunicación, las principales contribuciones realizadas en el campo de la educación en astronomía en los niveles primario, secundario y terciario, como punto de partida para la discusión de la actual inserción de los contenidos astronómicos en los nuevos contenidos curriculares de la EGB - Educación General Básica- y Polimodal, de la Reforma Educativa. En particular, se discuten los alcances de la educación formal y no formal, su importancia para la capacitación de profesores y maestros, y perspectivas a futuro.

  1. Differential matrix formalism for depolarizing anisotropic media.

    PubMed

    Ossikovski, Razvigor

    2011-06-15

    Azzam's differential matrix formalism [J. Opt. Soc. Am. 68, 1756 (1978)], originally developed for longitudinally inhomogeneous anisotropic nondepolarizing media, is extended to include depolarizing media. The generalization is physically interpreted in terms of means and uncertainties of the elementary optical properties of the medium, as well as of three anisotropy absorption parameters introduced to describe the depolarization. The formalism results in a particularly simple mathematical procedure for the retrieval of the elementary properties of a generally depolarizing anisotropic medium, assumed to be globally homogeneous, from its experimental Mueller matrix. The approach is illustrated on literature data and the conditions of its validity are identified and discussed.

  2. Geometric formalism for DNA quadruplex folding.

    PubMed

    Webba da Silva, Mateus

    2007-01-01

    Understanding the control of self-assembly and stereochemical properties of DNA higher order architectural folds is of fundamental importance in biology as well as biochemical technological applications. Guanine-rich DNA sequences can form tetrahelical architectures termed quadruplexes. A formalism is presented describing the interdependency of a set of structural descriptors as a geometric basis for folding of unimolecular quadruplex topologies. It represents a standard for interpretation of structural characteristics of quadruplexes, and is comprehensive in explicitly harmonizing the results of published literature with a unified language. The formalism is a fundamental step towards prediction of unimolecular quadruplex folding topologies from primary sequence.

  3. An extended IBA consistent- Q formalism applied to Ru and Pd isotopes

    NASA Astrophysics Data System (ADS)

    Bucurescu, D.; Cata, G.; Cutoiu, D.; Constantinescu, G.; Ivascu, M.; Zamfir, N. V.

    1986-12-01

    A consistent- Q formalism extended to an IBA-1 Hamiltonian applicable also in the U(5) limit, is applied to Ru and Pd isotopes with N around 60. A good description of energy levels and E2 transitions in these nuclei is obtained. The model is able to reproduce the main features of this transitional region, characterized by both rigid triaxial deformation and γ-softness.

  4. Projection formalism for constrained dynamical systems: from Newtonian to Hamiltonian mechanics.

    PubMed

    Kneller, Gerald R

    2007-10-28

    The Hamiltonian of a holonomically constrained dynamical many-particle system in Cartesian coordinates has been recently derived for applications in statistical mechanics [G. R. Kneller, J. Chem. Phys. 125, 114107 (2006)]. Using the same projector formalism, we show here the equivalence of the corresponding equations of motion with those obtained from a Newtonian and a Lagrangian description. In the case of Newtonian mechanics, the general case of nonholonomic constraints is considered, too.

  5. General formalism for the efficient calculation of the Hessian matrix of EM data misfit and Hessian-vector products based upon adjoint sources approach

    NASA Astrophysics Data System (ADS)

    Pankratov, Oleg; Kuvshinov, Alexey

    2015-03-01

    3-D electromagnetic (EM) studies of the Earth have advanced significantly over the past decade. Despite a certain success of the 3-D EM inversions of real data sets, the quantitative assessment of the recovered models is still a challenging problem. It is known that one can gain valuable information about model uncertainties from the analysis of Hessian matrix. However, even with modern computational capabilities the calculation of the Hessian matrix based on numerical differentiation is extremely time consuming. Much more efficient way to compute the Hessian matrix is provided by an `adjoint sources' methodology. The computation of Hessian matrix (and Hessian-vector products) using adjoint formulation is now well-established approach, especially in seismic inverse modelling. As for EM inverse modelling we did not find in the literature a description of the approach, which would allow EM researchers to apply this methodology in a straightforward manner to their scenario of interest. In the paper, we present formalism for the efficient calculation of the Hessian matrix using adjoint sources approach. We also show how this technique can be implemented to calculate multiple Hessian-vector products very efficiently. The formalism is general in the sense that it allows to work with responses that arise in EM problem set-ups either with natural- or controlled-source excitations. The formalism allows for various types of parametrization of the 3-D conductivity distribution. Using this methodology one can readily obtain appropriate formulae for the specific sounding methods. To illustrate the concept we provide such formulae for two EM techniques: magnetotellurics and controlled-source sounding with vertical magnetic dipole as a source.

  6. Multimedia content description framework

    NASA Technical Reports Server (NTRS)

    Bergman, Lawrence David (Inventor); Kim, Michelle Yoonk Yung (Inventor); Li, Chung-Sheng (Inventor); Mohan, Rakesh (Inventor); Smith, John Richard (Inventor)

    2003-01-01

    A framework is provided for describing multimedia content and a system in which a plurality of multimedia storage devices employing the content description methods of the present invention can interoperate. In accordance with one form of the present invention, the content description framework is a description scheme (DS) for describing streams or aggregations of multimedia objects, which may comprise audio, images, video, text, time series, and various other modalities. This description scheme can accommodate an essentially limitless number of descriptors in terms of features, semantics or metadata, and facilitate content-based search, index, and retrieval, among other capabilities, for both streamed or aggregated multimedia objects.

  7. 20 CFR 702.336 - Formal hearings; new issues.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Formal hearings; new issues. 702.336 Section... Procedures Formal Hearings § 702.336 Formal hearings; new issues. (a) If, during the course of the formal..., the hearing may be expanded to include the new issue. If in the opinion of the administrative...

  8. 20 CFR 702.332 - Formal hearings; how conducted.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Formal hearings; how conducted. 702.332 Section 702.332 Employees' Benefits EMPLOYMENT STANDARDS ADMINISTRATION, DEPARTMENT OF LABOR LONGSHOREMEN... Adjudication Procedures Formal Hearings § 702.332 Formal hearings; how conducted. Formal hearings shall...

  9. Connecting Formal and Informal Learning Experiences

    ERIC Educational Resources Information Center

    O'Mahony, Timothy Kieran

    2010-01-01

    The learning study reports on part of a larger project being lead by the author. In this dissertation I explore one goal of this project--to understand effects on student learning outcomes as a function of using different methods for connecting out-of-school experiential learning with formal school-based instruction. There is a long history of…

  10. Informal and Formal Learning of General Practitioners

    ERIC Educational Resources Information Center

    Spaan, Nadia Roos; Dekker, Anne R. J.; van der Velden, Alike W.; de Groot, Esther

    2016-01-01

    Purpose: The purpose of this study is to understand the influence of formal learning from a web-based training and informal (workplace) learning afterwards on the behaviour of general practitioners (GPs) with respect to prescription of antibiotics. Design/methodology/approach: To obtain insight in various learning processes, semi-structured…

  11. HEALTH EDUCATION THROUGH NON – FORMAL EDUCATION

    PubMed Central

    Sundararaj, P. Selva Peter; Kumar, P. Surendra

    1990-01-01

    The non-availability of health care in the rural area leads to the problems like infant mortality, infectious disease deaths and malnutrition. Rural health can be promoted both at preventive and promotive levels through non-formal education. PMID:22556504

  12. The formal path integral and quantum mechanics

    SciTech Connect

    Johnson-Freyd, Theo

    2010-11-15

    Given an arbitrary Lagrangian function on R{sup d} and a choice of classical path, one can try to define Feynman's path integral supported near the classical path as a formal power series parameterized by 'Feynman diagrams', although these diagrams may diverge. We compute this expansion and show that it is (formally, if there are ultraviolet divergences) invariant under volume-preserving changes of coordinates. We prove that if the ultraviolet divergences cancel at each order, then our formal path integral satisfies a 'Fubini theorem' expressing the standard composition law for the time evolution operator in quantum mechanics. Moreover, we show that when the Lagrangian is inhomogeneous quadratic in velocity such that its homogeneous-quadratic part is given by a matrix with constant determinant, then the divergences cancel at each order. Thus, by 'cutting and pasting' and choosing volume-compatible local coordinates, our construction defines a Feynman-diagrammatic 'formal path integral' for the nonrelativistic quantum mechanics of a charged particle moving in a Riemannian manifold with an external electromagnetic field.

  13. Formal Synthesis of (±)-Roseophilin

    PubMed Central

    Bitar, Abdallah Y.; Frontier, Alison J.

    2009-01-01

    A formal synthesis of (±)-roseophilin is described. Scandium(III)-catalyzed Nazarov cyclization of 2,5-disubstituted N-tosylpyrrole 19 gives a 5,5’-fused ketopyrrole, and ansa-bridge formation via π-allyl palladium macrocyclization gives 21. PMID:19053717

  14. An Elementary Formalism for General Relativity.

    ERIC Educational Resources Information Center

    diSessa, Andrea A.

    1981-01-01

    An elementary formalism is developed for representing curved space-time which allows transparent qualitative explanation of general relativistic effects and is used to make a conceptual analysis of Einstein's principle of equivalence. A final section outlines a number of student activities. (Author/SK)

  15. A Simplified Approach to Product Operator Formalism

    ERIC Educational Resources Information Center

    Spiese, Christopher E.

    2004-01-01

    The utilization of the simple and traditional vector model-based product operator formalism is highlighted. It is seen as a critical device in the area of nuclear magnetic resonance (NMR) spectrometry for a comprehensive analysis of spin coupling and quantum coherences.

  16. Teaching Some Informatics Concepts Using Formal System

    ERIC Educational Resources Information Center

    Yang, Sojung; Park, Seongbin

    2014-01-01

    There are many important issues in informatics and many agree that algorithms and programming are most important issues that need to be included in informatics education (Dagiene and Jevsikova, 2012). In this paper, we propose how some of these issues can be easily taught using the notion of a formal system which consists of axioms and inference…

  17. Helping Students Understand Formal Chemical Concepts.

    ERIC Educational Resources Information Center

    Ward, Charles R.; Herron, J. Dudley

    1980-01-01

    Investigated outcomes of the use of the learning cycle, which divides instruction into the Piagetian phases of exploration, invention, and discovery in general college chemistry laboratory experiments. Differences between concrete and formal operational students were explored in students' ability to master chemistry material varying in cognitive…

  18. Informal Science Learning in the Formal Classroom

    ERIC Educational Resources Information Center

    Walsh, Lori; Straits, William

    2014-01-01

    In this article the authors share advice from the viewpoints of both a formal and informal educator that will help teachers identify the right Informal Science Institutions (ISIs)--institutions that specialize in learning that occurs outside of the school setting--to maximize their students' learning and use informal education to their…

  19. The Transition to Formal Thinking in Mathematics

    ERIC Educational Resources Information Center

    Tall, David

    2008-01-01

    This paper focuses on the changes in thinking involved in the transition from school mathematics to formal proof in pure mathematics at university. School mathematics is seen as a combination of visual representations, including geometry and graphs, together with symbolic calculations and manipulations. Pure mathematics in university shifts…

  20. Quantum formalism to describe binocular rivalry.

    PubMed

    Manousakis, Efstratios

    2009-11-01

    On the basis of the general character and operation of the process of perception, a formalism is sought to mathematically describe the subjective or abstract/mental process of perception. It is shown that the formalism of orthodox quantum theory of measurement, where the observer plays a key role, is a broader mathematical foundation which can be adopted to describe the dynamics of the subjective experience. The mathematical formalism describes the psychophysical dynamics of the subjective or cognitive experience as communicated to us by the subject. Subsequently, the formalism is used to describe simple perception processes and, in particular, to describe the probability distribution of dominance duration obtained from the testimony of subjects experiencing binocular rivalry. Using this theory and parameters based on known values of neuronal oscillation frequencies and firing rates, the calculated probability distribution of dominance duration of rival states in binocular rivalry under various conditions is found to be in good agreement with available experimental data. This theory naturally explains an observed marked increase in dominance duration in binocular rivalry upon periodic interruption of stimulus and yields testable predictions for the distribution of perceptual alteration in time.

  1. 50 CFR 402.14 - Formal consultation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...

  2. 50 CFR 402.14 - Formal consultation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...

  3. 50 CFR 402.14 - Formal consultation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...

  4. 50 CFR 402.14 - Formal consultation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...

  5. 50 CFR 402.14 - Formal consultation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS SUBCHAPTER A INTERAGENCY COOPERATION-ENDANGERED SPECIES ACT OF 1973, AS AMENDED Consultation Procedures § 402.14 Formal consultation. (a... time to determine whether any action may affect listed species or critical habitat. If such...

  6. Formal Schema Theory and Teaching EFL Reading

    ERIC Educational Resources Information Center

    Young, Barbara N; Man, Zhou

    2005-01-01

    Inquirers designed and conducted a study investigating whether or not results derived from previous research focusing on teaching and learning English as a native or foreign language would be replicated in a learning environment in which English is taught as a foreign language as in China. Because activation of formal schemata plays an important…

  7. Situationally Embodied Curriculum: Relating Formalisms and Contexts

    ERIC Educational Resources Information Center

    Barab, Sasha; Zuiker, Steve; Warren, Scott; Hickey, Dan; Ingram-Goble, Adam; Kwon, Eun-Ju; Kouper, Inna; Herring, Susan C.

    2007-01-01

    This study describes an example of design-based research in which we make theoretical improvements in our understanding, in part based on empirical work, and use these to revise our curriculum and, simultaneously, our evolving theory of the relations between contexts and disciplinary formalisms. Prior to this study, we completed a first cycle of…

  8. 28 CFR 68.39 - Formal hearings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ALIENS, UNFAIR IMMIGRATION-RELATED EMPLOYMENT PRACTICES, AND DOCUMENT FRAUD § 68.39 Formal hearings. (a... Law Judge shall have jurisdiction to decide all issues of fact and related issues of law. (c) Rights of parties. Every party shall have the right of timely notice and all other rights essential to...

  9. 28 CFR 68.39 - Formal hearings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ALIENS, UNFAIR IMMIGRATION-RELATED EMPLOYMENT PRACTICES, AND DOCUMENT FRAUD § 68.39 Formal hearings. (a... Law Judge shall have jurisdiction to decide all issues of fact and related issues of law. (c) Rights of parties. Every party shall have the right of timely notice and all other rights essential to...

  10. 28 CFR 68.39 - Formal hearings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ALIENS, UNFAIR IMMIGRATION-RELATED EMPLOYMENT PRACTICES, AND DOCUMENT FRAUD § 68.39 Formal hearings. (a... Law Judge shall have jurisdiction to decide all issues of fact and related issues of law. (c) Rights of parties. Every party shall have the right of timely notice and all other rights essential to...

  11. STUDENTS' MANUAL OF MODERN FORMAL TAMIL.

    ERIC Educational Resources Information Center

    LISKER, LEIGH; VAIDYANATHAN, S.

    A BEGINNING TEXT IN TAMIL, ONE OF THE MOST WIDELY SPOKEN DRAVIDIAN LANGUAGES IN INDIA, IS PRESENTED. THE FORMAL LANGUAGE STYLE USED IN THESE MATERIALS REPRESENTS THE STYLE USED IN LECTURES, RADIO BROADCASTS, AND CITATION FORMS, AND IS ESSENTIALLY THE SPOKEN VERSION OF THE MODERN STANDARD WRITTEN TAMIL. THIS MANUAL, WHILE SERVING AS INTRODUCTION TO…

  12. Rhythmic Characteristics of Colloquial and Formal Tamil

    ERIC Educational Resources Information Center

    Keane, Elinor

    2006-01-01

    Application of recently developed rhythmic measures to passages of read speech in colloquial and formal Tamil revealed some significant differences between the two varieties, which are in diglossic distribution. Both were also distinguished from a set of control data from British English speakers reading an equivalent passage. The findings have…

  13. Verification Games: Crowd-Sourced Formal Verification

    DTIC Science & Technology

    2016-03-01

    Formal Verification the verification tools developed by the Programming Languages and Software Engineering group were improved. A series of games...were developed by the Center for Game Science: Pipe Jam, Traffic Jam, Flow Jam and Paradox. Verification tools and games were integrated to verify...N/A i Contents List of Figures 1. SUMMARY .............................................................................................. 1 2

  14. Partial Acquisition of the Formal Operations.

    ERIC Educational Resources Information Center

    Greene, Anita-Louise

    Sixty adolescents, stratified by sex and grade level (i.e., 9th, 12th, and college sophomore) participated in an examination of Piaget's suggestion that the formal operations are prerequisite to the development of political idealism, abstract thought and future time perspective in adolescence. Analysis of the cognition data revealed that the…

  15. HIV Education in the Formal Curriculum

    ERIC Educational Resources Information Center

    Nsubuga, Yusuf K.; Bonnet, Sandrine

    2009-01-01

    The AIDS epidemic presents a complex of issues that require global answers, involving entire societies. The only sustainable solution is to include all sectors of society in a multidisciplinary collaboration, within which the formal education system plays a key role in delivering a comprehensive response to the disease at the national level.…

  16. A Preliminary Search for Formal Operations Structures.

    ERIC Educational Resources Information Center

    Neimark, Edith D.

    In a test the presence or absence of a "structure" in the individual's cognitive processes of formal operations thinking, 61 fourth, fifth, and sixth grade students were administered three tasks supposedly requiring such a method of thinking. The three tasks were (1) a problem solving task (PS), (2) a chemistry task requiring a certain combination…

  17. Formal and Applied Counseling in Israel

    ERIC Educational Resources Information Center

    Israelashvili, Moshe; Wegman-Rozi, Orit

    2012-01-01

    Living in Israel is intensive and demanding but also meaningful and exciting. This article addresses the gap between the narrowly defined formal status of counseling in Israel and the widespread occurrence of counseling in various settings. It is argued that several recent changes, especially in the definition of treatment, along with the…

  18. A formal theory of the selfish gene.

    PubMed

    Gardner, A; Welch, J J

    2011-08-01

    Adaptation is conventionally regarded as occurring at the level of the individual organism. In contrast, the theory of the selfish gene proposes that it is more correct to view adaptation as occurring at the level of the gene. This view has received much popular attention, yet has enjoyed only limited uptake in the primary research literature. Indeed, the idea of ascribing goals and strategies to genes has been highly controversial. Here, we develop a formal theory of the selfish gene, using optimization theory to capture the analogy of 'gene as fitness-maximizing agent' in mathematical terms. We provide formal justification for this view of adaptation by deriving mathematical correspondences that translate the optimization formalism into dynamical population genetics. We show that in the context of social interactions between genes, it is the gene's inclusive fitness that provides the appropriate maximand. Hence, genic selection can drive the evolution of altruistic genes. Finally, we use the formalism to assess the various criticisms that have been levelled at the theory of the selfish gene, dispelling some and strengthening others.

  19. A Study of Relationships Between Formal Organizational Structure and Organizational Climate in Selected Urban and Suburban Schools.

    ERIC Educational Resources Information Center

    Ames, John L.; And Others

    In this study, assessment of the formal organizational structure was limited to a determination of authority and responsibility in personnel, supervision, curriculum, policymaking, and community relations. The study data were gathered from the results of the (1) Organizational Climate Description Questionnaire, (2) Professional Self-Enchancement…

  20. Can Schools Be Autonomous in a Centralised Educational System?: On Formal and Actual School Autonomy in the Italian Context

    ERIC Educational Resources Information Center

    Agasisti, Tommaso; Catalano, Giuseppe; Sibiano, Piergiacomo

    2013-01-01

    Purpose: The purpose of this paper is to examine the difference between formal and real school autonomy in the Italian educational system. The Italian case is characterised by low levels of school autonomy. It is interesting to consider whether heterogeneity of patterns is possible in this context. A description of this heterogeneity is provided…

  1. Formal Assurance Certifiable Tooling Formal Assurance Certifiable Tooling Strategy Final Report

    NASA Technical Reports Server (NTRS)

    Bush, Eric; Oglesby, David; Bhatt, Devesh; Murugesan, Anitha; Engstrom, Eric; Mueller, Joe; Pelican, Michael

    2017-01-01

    This is the Final Report of a research project to investigate issues and provide guidance for the qualification of formal methods tools under the DO-330 qualification process. It consisted of three major subtasks spread over two years: 1) an assessment of theoretical soundness issues that may affect qualification for three categories of formal methods tools, 2) a case study simulating the DO-330 qualification of two actual tool sets, and 3) an investigation of risk mitigation strategies that might be applied to chains of such formal methods tools in order to increase confidence in their certification of airborne software.

  2. On the Use of Robotics Formalism in the Description and Modeling of Antenna Range Positioners

    NASA Technical Reports Server (NTRS)

    Beckon, R. J.

    1998-01-01

    A typical positioner used for positioning an antenna under test on an antenna range has two or three rotation axes arranged in such a manner as to facilitate the taking of data along certain paths through the antenna pattern.

  3. On the Use of Robotics Formalism in the Description and Modeling of Antenna Range Positioners

    NASA Technical Reports Server (NTRS)

    Beckon, R. J.

    1997-01-01

    A typical positioner used for positioning an antenna under test on an antenna range has two or three rotation axes arranged in such a manner as to facilitate the taking of a data along certain paths through the antenna pattern.

  4. The 2(2S + 1)-formalism and its connection with other descriptions

    NASA Astrophysics Data System (ADS)

    Dvoeglazov, Valeriy V.

    2016-02-01

    In the framework of the Joos-Weinberg 2(2S + 1)-theory for massless particles, the dynamical invariants have been derived from the Lagrangian density which is considered to be a 4-vector. A la Majorana interpretation of the 6-component “spinors”, the field operators of S = 1 particles, as the left- and right-circularly polarized radiation, leads us to the conserved quantities which are analogous to those obtained by Lipkin and Sudbery. The scalar Lagrangian of the Joos-Weinberg theory is shown to be equivalent to the Lagrangian of a free massless field, introduced by Hayashi. As a consequence of a new “gauge” invariance this skew-symmetric field describes physical particles with the longitudinal components only. The interaction of the spinor field with the Weinberg’s 2(2S + 1)-component massless field is considered. New interpretation of the Weinberg field function is proposed.

  5. Physics 3204. Course Description.

    ERIC Educational Resources Information Center

    Newfoundland and Labrador Dept. of Education.

    A description of the physics 3204 course in Newfoundland and Labrador is provided. The description includes: (1) statement of purpose, including general objectives of science education; (2) a list of six course objectives; (3) course content for units on sound, light, optical instruments, electrostatics, current electricity, Michael Faraday and…

  6. Descriptive Metadata: Emerging Standards.

    ERIC Educational Resources Information Center

    Ahronheim, Judith R.

    1998-01-01

    Discusses metadata, digital resources, cross-disciplinary activity, and standards. Highlights include Standard Generalized Markup Language (SGML); Extensible Markup Language (XML); Dublin Core; Resource Description Framework (RDF); Text Encoding Initiative (TEI); Encoded Archival Description (EAD); art and cultural-heritage metadata initiatives;…

  7. Formal Safety Certification of Aerospace Software

    NASA Technical Reports Server (NTRS)

    Denney, Ewen; Fischer, Bernd

    2005-01-01

    In principle, formal methods offer many advantages for aerospace software development: they can help to achieve ultra-high reliability, and they can be used to provide evidence of the reliability claims which can then be subjected to external scrutiny. However, despite years of research and many advances in the underlying formalisms of specification, semantics, and logic, formal methods are not much used in practice. In our opinion this is related to three major shortcomings. First, the application of formal methods is still expensive because they are labor- and knowledge-intensive. Second, they are difficult to scale up to complex systems because they are based on deep mathematical insights about the behavior of the systems (t.e., they rely on the "heroic proof"). Third, the proofs can be difficult to interpret, and typically stand in isolation from the original code. In this paper, we describe a tool for formally demonstrating safety-relevant aspects of aerospace software, which largely circumvents these problems. We focus on safely properties because it has been observed that safety violations such as out-of-bounds memory accesses or use of uninitialized variables constitute the majority of the errors found in the aerospace domain. In our approach, safety means that the program will not violate a set of rules that can range for the simple memory access rules to high-level flight rules. These different safety properties are formalized as different safety policies in Hoare logic, which are then used by a verification condition generator along with the code and logical annotations in order to derive formal safety conditions; these are then proven using an automated theorem prover. Our certification system is currently integrated into a model-based code generation toolset that generates the annotations together with the code. However, this automated formal certification technology is not exclusively constrained to our code generator and could, in principle, also be

  8. Fluid description of multi-component solar partially ionized plasma

    SciTech Connect

    Khomenko, E. Collados, M.; Vitas, N.; Díaz, A.

    2014-09-15

    We derive self-consistent formalism for the description of multi-component partially ionized solar plasma, by means of the coupled equations for the charged and neutral components for an arbitrary number of chemical species, and the radiation field. All approximations and assumptions are carefully considered. Generalized Ohm's law is derived for the single-fluid and two-fluid formalism. Our approach is analytical with some order-of-magnitude support calculations. After general equations are developed, we particularize to some frequently considered cases as for the interaction of matter and radiation.

  9. Methodology for the description and validation of communication protocols

    NASA Astrophysics Data System (ADS)

    Pattavina, A.; Roveri, A.; Trigila, S.

    1981-12-01

    The models which may be used for the formal description of communication protocols, such as those required for complex computer networks, are analyzed and compared. Two types of models are studied: (1) the abstract automata models including finite state machines, UCLA graphs, Petri nets and formal grammars, and (2) the algorithmic models based on high level programming languages, including sequential languages, such as Pascal, Simula, PL/1, and concurrent languages such as Concurrent Pascal and Chill. Advantages and difficulties are found in both type of models. The evolution of hybrid models is mentionned.

  10. General Green's function formalism for layered systems: Wave function approach

    NASA Astrophysics Data System (ADS)

    Zhang, Shu-Hui; Yang, Wen; Chang, Kai

    2017-02-01

    The single-particle Green's function (GF) of mesoscopic structures plays a central role in mesoscopic quantum transport. The recursive GF technique is a standard tool to compute this quantity numerically, but it lacks physical transparency and is limited to relatively small systems. Here we present a numerically efficient and physically transparent GF formalism for a general layered structure. In contrast to the recursive GF that directly calculates the GF through the Dyson equations, our approach converts the calculation of the GF to the generation and subsequent propagation of a scattering wave function emanating from a local excitation. This viewpoint not only allows us to reproduce existing results in a concise and physically intuitive manner, but also provides analytical expressions of the GF in terms of a generalized scattering matrix. This identifies the contributions from each individual scattering channel to the GF and hence allows this information to be extracted quantitatively from dual-probe STM experiments. The simplicity and physical transparency of the formalism further allows us to treat the multiple reflection analytically and derive an analytical rule to construct the GF of a general layered system. This could significantly reduce the computational time and enable quantum transport calculations for large samples. We apply this formalism to perform both analytical analysis and numerical simulation for the two-dimensional conductance map of a realistic graphene p -n junction. The results demonstrate the possibility of observing the spatially resolved interference pattern caused by negative refraction and further reveal a few interesting features, such as the distance-independent conductance and its quadratic dependence on the carrier concentration, as opposed to the linear dependence in uniform graphene.

  11. Measurements and mathematical formalism of quantum mechanics

    NASA Astrophysics Data System (ADS)

    Slavnov, D. A.

    2007-03-01

    A scheme for constructing quantum mechanics is given that does not have Hilbert space and linear operators as its basic elements. Instead, a version of algebraic approach is considered. Elements of a noncommutative algebra (observables) and functionals on this algebra (elementary states) associated with results of single measurements are used as primary components of the scheme. On the one hand, it is possible to use within the scheme the formalism of the standard (Kolmogorov) probability theory, and, on the other hand, it is possible to reproduce the mathematical formalism of standard quantum mechanics, and to study the limits of its applicability. A short outline is given of the necessary material from the theory of algebras and probability theory. It is described how the mathematical scheme of the paper agrees with the theory of quantum measurements, and avoids quantum paradoxes.

  12. A Formal Framework for Workflow Analysis

    NASA Astrophysics Data System (ADS)

    Cravo, Glória

    2010-09-01

    In this paper we provide a new formal framework to model and analyse workflows. A workflow is the formal definition of a business process that consists in the execution of tasks in order to achieve a certain objective. In our work we describe a workflow as a graph whose vertices represent tasks and the arcs are associated to workflow transitions. Each task has associated an input/output logic operator. This logic operator can be the logical AND (•), the OR (⊗), or the XOR -exclusive-or—(⊕). Moreover, we introduce algebraic concepts in order to completely describe completely the structure of workflows. We also introduce the concept of logical termination. Finally, we provide a necessary and sufficient condition for this property to hold.

  13. Generalizing Prototype Theory: A Formal Quantum Framework

    PubMed Central

    Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro

    2016-01-01

    Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436

  14. Formal Management of CAD/CAM Processes

    NASA Astrophysics Data System (ADS)

    Kohlhase, Michael; Lemburg, Johannes; Schröder, Lutz; Schulz, Ewaryst

    Systematic engineering design processes have many aspects in common with software engineering, with CAD/CAM objects replacing program code as the implementation stage of the development. They are, however, currently considerably less formal. We propose to draw on the mentioned similarities and transfer methods from software engineering to engineering design in order to enhance in particular the reliability and reusability of engineering processes. We lay out a vision of a document-oriented design process that integrates CAD/CAM documents with requirement specifications; as a first step towards supporting such a process, we present a tool that interfaces a CAD system with program verification workflows, thus allowing for completely formalised development strands within a semi-formal methodology.

  15. Theory of connectivity for formally symmetric operators

    PubMed Central

    Herrera, Ismael

    1977-01-01

    A previous paper introduced the notion of complete connectivity conditions and developed variational principles for diffraction problems subjected to such restrictions. Here, an abstract definition of formally symmetric operators is given and it is shown that the problem of connecting solutions of equations associated with this kind of operators leads to complete connectivity conditions. The variational principles previously developed as well as a present more general one are thus applicable. The problem of connecting solutions defined in different regions is basic for finite element formulations. Formally symmetric operators occur in many branches of science and engineering. Applications are given here to potential theory, wave propagation, elasticity, and a general class of boundary integral equations. PMID:16592459

  16. Hartle formalism for rotating Newtonian configurations

    NASA Astrophysics Data System (ADS)

    Boshkayev, Kuantay; Quevedo, Hernando; Kalymova, Zhanerke; Zhami, Bakytzhan

    2016-11-01

    We apply the Hartle formalism to study equilibrium configurations in the framework of Newtonian gravity. This approach allows one to study in a simple manner the properties of the interior gravitational field in the case of static as well as stationary rotating stars in hydrostatic equilibrium. It is shown that the gravitational equilibrium conditions reduce to a system of ordinary differential equations which can be integrated numerically. We derive all the relevant equations up to the second order in the angular velocity. Moreover, we find explicitly the total mass, the moment of inertia, the quadrupole moment, the polar and equatorial radii, the eccentricity and the gravitational binding energy of the rotating body. We also present the procedure to calculate the gravitational Love number. We test the formalism in the case of white dwarfs and show its compatibility with the known results in the literature.

  17. Generalizing Prototype Theory: A Formal Quantum Framework.

    PubMed

    Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro

    2016-01-01

    Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper.

  18. Formal Definition of Measures for BPMN Models

    NASA Astrophysics Data System (ADS)

    Reynoso, Luis; Rolón, Elvira; Genero, Marcela; García, Félix; Ruiz, Francisco; Piattini, Mario

    Business process models are currently attaining more relevance, and more attention is therefore being paid to their quality. This situation led us to define a set of measures for the understandability of BPMN models, which is shown in a previous work. We focus on understandability since a model must be well understood before any changes are made to it. These measures were originally informally defined in natural language. As is well known, natural language is ambiguous and may lead to misunderstandings and a misinterpretation of the concepts captured by a measure and the way in which the measure value is obtained. This has motivated us to provide the formal definition of the proposed measures using OCL (Object Constraint Language) upon the BPMN (Business Process Modeling Notation) metamodel presented in this paper. The main advantages and lessons learned (which were obtained both from the current work and from previous works carried out in relation to the formal definition of other measures) are also summarized.

  19. Formal verification of human-automation interaction.

    PubMed

    Degani, Asaf; Heymann, Michael

    2002-01-01

    This paper discusses a formal and rigorous approach to the analysis of operator interaction with machines. It addresses the acute problem of detecting design errors in human-machine interaction and focuses on verifying the correctness of the interaction in complex and automated control systems. The paper describes a systematic methodology for evaluating whether the interface provides the necessary information about the machine to enable the operator to perform a specified task successfully and unambiguously. It also addresses the adequacy of information provided to the user via training material (e.g., user manual) about the machine's behavior. The essentials of the methodology, which can be automated and applied to the verification of large systems, are illustrated by several examples and through a case study of pilot interaction with an autopilot aboard a modern commercial aircraft. The expected application of this methodology is an augmentation and enhancement, by formal verification, of human-automation interfaces.

  20. Group adaptation, formal darwinism and contextual analysis.

    PubMed

    Okasha, S; Paternotte, C

    2012-06-01

    We consider the question: under what circumstances can the concept of adaptation be applied to groups, rather than individuals? Gardner and Grafen (2009, J. Evol. Biol.22: 659-671) develop a novel approach to this question, building on Grafen's 'formal Darwinism' project, which defines adaptation in terms of links between evolutionary dynamics and optimization. They conclude that only clonal groups, and to a lesser extent groups in which reproductive competition is repressed, can be considered as adaptive units. We re-examine the conditions under which the selection-optimization links hold at the group level. We focus on an important distinction between two ways of understanding the links, which have different implications regarding group adaptationism. We show how the formal Darwinism approach can be reconciled with G.C. Williams' famous analysis of group adaptation, and we consider the relationships between group adaptation, the Price equation approach to multi-level selection, and the alternative approach based on contextual analysis.

  1. Viscous warm inflation: Hamilton-Jacobi formalism

    NASA Astrophysics Data System (ADS)

    Akhtari, L.; Mohammadi, A.; Sayar, K.; Saaidi, Kh.

    2017-04-01

    Using Hamilton-Jacobi formalism, the scenario of warm inflation with viscous pressure is considered. The formalism gives a way of computing the slow-rolling parameter without extra approximation, and it is well-known as a powerful method in cold inflation. The model is studied in detail for three different cases of the dissipation and bulk viscous pressure coefficients. In the first case where both coefficients are taken as constant, it is shown that the case could not portray warm inflationary scenario compatible with observational data even it is possible to restrict the model parameters. For other cases, the results shows that the model could properly predicts the perturbation parameters in which they stay in perfect agreement with Planck data. As a further argument, r -ns and αs -ns are drown that show the acquired result could stand in acceptable area expressing a compatibility with observational data.

  2. Stochastic Formal Correctness of Numerical Algorithms

    NASA Technical Reports Server (NTRS)

    Daumas, Marc; Lester, David; Martin-Dorel, Erik; Truffert, Annick

    2009-01-01

    We provide a framework to bound the probability that accumulated errors were never above a given threshold on numerical algorithms. Such algorithms are used for example in aircraft and nuclear power plants. This report contains simple formulas based on Levy's and Markov's inequalities and it presents a formal theory of random variables with a special focus on producing concrete results. We selected four very common applications that fit in our framework and cover the common practices of systems that evolve for a long time. We compute the number of bits that remain continuously significant in the first two applications with a probability of failure around one out of a billion, where worst case analysis considers that no significant bit remains. We are using PVS as such formal tools force explicit statement of all hypotheses and prevent incorrect uses of theorems.

  3. Experience report: Using formal methods for requirements analysis of critical spacecraft software

    NASA Technical Reports Server (NTRS)

    Lutz, Robyn R.; Ampo, Yoko

    1994-01-01

    Formal specification and analysis of requirements continues to gain support as a method for producing more reliable software. However, the introduction of formal methods to a large software project is difficult, due in part to the unfamiliarity of the specification languages and the lack of graphics. This paper reports results of an investigation into the effectiveness of formal methods as an aid to the requirements analysis of critical, system-level fault-protection software on a spacecraft currently under development. Our experience indicates that formal specification and analysis can enhance the accuracy of the requirements and add assurance prior to design development in this domain. The work described here is part of a larger, NASA-funded research project whose purpose is to use formal-methods techniques to improve the quality of software in space applications. The demonstration project described here is part of the effort to evaluate experimentally the effectiveness of supplementing traditional engineering approaches to requirements specification with the more rigorous specification and analysis available with formal methods.

  4. A formalism for evaluating analytically the cross-correlation structure of a firing-rate network model.

    PubMed

    Fasoli, Diego; Faugeras, Olivier; Panzeri, Stefano

    2015-01-01

    We introduce a new formalism for evaluating analytically the cross-correlation structure of a finite-size firing-rate network with recurrent connections. The analysis performs a first-order perturbative expansion of neural activity equations that include three different sources of randomness: the background noise of the membrane potentials, their initial conditions, and the distribution of the recurrent synaptic weights. This allows the analytical quantification of the relationship between anatomical and functional connectivity, i.e. of how the synaptic connections determine the statistical dependencies at any order among different neurons. The technique we develop is general, but for simplicity and clarity we demonstrate its efficacy by applying it to the case of synaptic connections described by regular graphs. The analytical equations so obtained reveal previously unknown behaviors of recurrent firing-rate networks, especially on how correlations are modified by the external input, by the finite size of the network, by the density of the anatomical connections and by correlation in sources of randomness. In particular, we show that a strong input can make the neurons almost independent, suggesting that functional connectivity does not depend only on the static anatomical connectivity, but also on the external inputs. Moreover we prove that in general it is not possible to find a mean-field description à la Sznitman of the network, if the anatomical connections are too sparse or our three sources of variability are correlated. To conclude, we show a very counterintuitive phenomenon, which we call stochastic synchronization, through which neurons become almost perfectly correlated even if the sources of randomness are independent. Due to its ability to quantify how activity of individual neurons and the correlation among them depends upon external inputs, the formalism introduced here can serve as a basis for exploring analytically the computational capability of

  5. Decidability of formal theories and hyperincursivity theory

    NASA Astrophysics Data System (ADS)

    Grappone, Arturo G.

    2000-05-01

    This paper shows the limits of the Proof Standard Theory (briefly, PST) and gives some ideas of how to build a proof anticipatory theory (briefly, PAT) that has no such limits. Also, this paper considers that Gödel's proof of the undecidability of Principia Mathematica formal theory is not valid for axiomatic theories that use a PAT to build their proofs because the (hyper)incursive functions are self-representable.

  6. Fourth NASA Langley Formal Methods Workshop

    NASA Technical Reports Server (NTRS)

    Holloway, C. Michael (Compiler); Hayhurst, Kelly J. (Compiler)

    1997-01-01

    This publication consists of papers presented at NASA Langley Research Center's fourth workshop on the application of formal methods to the design and verification of life-critical systems. Topic considered include: Proving properties of accident; modeling and validating SAFER in VDM-SL; requirement analysis of real-time control systems using PVS; a tabular language for system design; automated deductive verification of parallel systems. Also included is a fundamental hardware design in PVS.

  7. Flexible receiver adapter formal design review

    SciTech Connect

    Krieg, S.A.

    1995-06-13

    This memo summarizes the results of the Formal (90%) Design Review process and meetings held to evaluate the design of the Flexible Receiver Adapters, support platforms, and associated equipment. The equipment is part of the Flexible Receiver System used to remove, transport, and store long length contaminated equipment and components from both the double and single-shell underground storage tanks at the 200 area tank farms.

  8. Terra in K-16 formal education settings

    NASA Astrophysics Data System (ADS)

    Chambers, L. H.; Fischer, J. D.; Lewis, P. M.; Moore, S. W.; Oots, P. C.; Rogerson, T. M.; Hitke, K. M.; Riebeek, H.

    2009-12-01

    Since it began, the Terra mission has had an active presence in formal education at the K-16 level. This educational presence was provided through the S’COOL project for the first five years of the mission, joined by the MY NASA DATA project for the second five years. The Students’ Cloud Observations On-Line (S’COOL) Project, begun in 1997 under the auspices of the Clouds and the Earth’s Radiant Energy System (CERES) project, seeks to motivate students across the entire K-12 spectrum to learn science basics and how they tie in to a larger picture. Beginning early on, college level participants have also participated in the project, both in science classes and in science education coursework. The project uses the connection to an on-going NASA science investigation as a powerful motivator for student observations, analysis and learning, and has reached around the globe as shown in the world map. This poster will review the impact that Terra, through S’COOL, has made in formal education over the last decade. The MY NASA DATA Project began in 2004 under the NASA Research, Education and Applications Solutions Network (REASoN). A 5-year REASoN grant enabled the creation of an extensive website which wraps easily accessible Earth science data - including Terra parameters from CERES (involving MODIS data fusion), MISR, and MOPITT (an example for carbon monoxide is given in the graph, with dark areas indicating high CO levels) - with explanatory material written at the middle school level, and an extensive collection of peer-reviewed lesson plans. The MY NASA DATA site has a rapidly growing user-base and was recently adopted by a number of NASA Earth Science missions, in addition to Terra, as a formal education arm of their Education and Public Outreach efforts. This poster will summarize the contributions that Terra, through MY NASA DATA, has made to formal education since 2004.

  9. Structure Based Formal Methods for Software Engineering

    DTIC Science & Technology

    1989-07-27

    9 3.4 The Initial PegaSys Prototype ....... ...................... 9 4 Related Research 11 References 12 Accession For NI T 1... PegaSys - that uses pictures as for- mal documentation. To our knowledge, PegaSys is the first system to manipu- late nontrivial design structures in...The Initial PegaSys Prototype PegaSys is a display-oriented, interactive environment that uses intuitive graphical pictures as formal documentation to

  10. Formal Synthesis of (±)-Platensimycin

    PubMed Central

    Zou, Yefen; Chen, Chun-Hsing; Taylor, Christopher D.; Foxman, Bruce M.; Snider, Barry B.

    2008-01-01

    Reductive alkylation of 5-methoxy-1-tetralone (6) with 2,3-dibromopropene gave an equilibrium mixture of bicyclic diones 7 (51%) and 8 (35%). Radical cyclization of 7 afforded tricyclic dione 5 (84%), which was reduced, cyclized and dehydrated to give tetracyclic alkene 13 in 63% yield. Allylic oxidation of 13 with SeO2 and activated MnO2 afforded enone 2 in 85% yield, thereby completing a short formal synthesis of (±)-platensimycin. PMID:17407302

  11. Formalized Epistemology in a Philosophical Perspective

    NASA Astrophysics Data System (ADS)

    Barreau, Hervé

    The need for a formalized epistemology is recognized by all scholars who think that the relativity of all sciences must not be referred to a social relativism. In XXth century, Husserl was the protagonist of such an epistemic philosophy. But this philosophy was more successful in social and human sciences than in natural sciences. In this latter domain, quantum mechanics obeys the requirements of a Kantien perspective in a more precise sense that was the case with Newtonian mechanics.

  12. [How to write an article: formal aspects].

    PubMed

    Corral de la Calle, M A; Encinas de la Iglesia, J

    2013-06-01

    Scientific research and the publication of the results of the studies go hand in hand. Exquisite research methods can only be adequately reflected in formal publication with the optimum structure. To ensure the success of this process, it is necessary to follow orderly steps, including selecting the journal in which to publish and following the instructions to authors strictly as well as the guidelines elaborated by diverse societies of editors and other institutions. It is also necessary to structure the contents of the article in a logical and attractive way and to use an accurate, clear, and concise style of language. Although not all the authors are directly involved in the actual writing, elaborating a scientific article is a collective undertaking that does not finish until the article is published. This article provides practical advice about formal and not-so-formal details to take into account when writing a scientific article as well as references that will help readers find more information in greater detail.

  13. A thermodynamical formalism describing mechanical interactions

    NASA Astrophysics Data System (ADS)

    Andrade, R. F. S.; Souza, A. M. C.; Curado, E. M. F.; Nobre, F. D.

    2014-10-01

    The dynamical behavior of an overdamped mechanical model devoid of any usual thermal effects is analyzed by a formalism that is similar to usual thermodynamics, and completely independent of any ad hoc assumption of a probability distribution of states in phase space of the mechanical model. It leads to the definition of a new entropy function, which does not coincide with the usual thermodynamical entropy. The new step making the difference to previous studies of this system is the identification of two non-equivalent mechanical interaction mechanisms, which are defined and identified as work and pseudo-heat. Together with the introduced effective temperature θ, they make it possible to characterize the equivalent to isothermal, adiabatic, isobaric, and isochoric processes. Three statements, formally analogous to the zeroth, first, and second law of thermodynamics, are issued. The statement of the second law results from the asymmetry in the way energy can be exchanged along the two processes. A Carnot cycle is defined, for which the efficiency is expressed in terms of θ in the operating pseudo-heat reservoirs. The analogous Clausius theorem for the system operating an arbitrary reversible cycle is proved, leading to the new entropy function. Consequences of the extension of thermodynamic formalism to mechanical models with different processes of transferring energy are discussed.

  14. Teaching Associates: Bridging Informal and Formal Mechanisms of Support for Graduate Student Instructors

    ERIC Educational Resources Information Center

    Jungels, Amanda M.; Brown, Marni A.; Stombler, Mindy; Yasumoto, Saori

    2014-01-01

    Faculty members and graduate student instructors (GSIs) spend a significant portion of their time in the classroom. Much of the literature calls for formal training for graduate students in pedagogy and teaching techniques (DeCesare 2003), and increasing attention has been paid to the benefits of informal supports for GSIs, such as peer networks.…

  15. An Ill-Structured PBL-Based Microprocessor Course without Formal Laboratory

    ERIC Educational Resources Information Center

    Kim, Jungkuk

    2012-01-01

    This paper introduces a problem-based learning (PBL) microprocessor application course designed according to the following strategies: 1) hands-on training without having a formal laboratory, and 2) intense student-centered cooperative learning through an ill-structured problem. PBL was adopted as the core educational technique of the course to…

  16. "It's Never Too Late." A Learning Pack for Older People with Few or No Formal Qualifications.

    ERIC Educational Resources Information Center

    Oxford Univ. (England). Ruskin Coll.

    This learning pack, which was developed in Britain primarily for use with small groups of older adults who have had little formal education, contains nine self-contained units of learning activities dealing with topics related to older adults' everyday lives. The following topics are covered: techniques for organizing and running a group; myths…

  17. A Formal Model of Partitioning for Integrated Modular Avionics

    NASA Technical Reports Server (NTRS)

    DiVito, Ben L.

    1998-01-01

    The aviation industry is gradually moving toward the use of integrated modular avionics (IMA) for civilian transport aircraft. An important concern for IMA is ensuring that applications are safely partitioned so they cannot interfere with one another. We have investigated the problem of ensuring safe partitioning and logical non-interference among separate applications running on a shared Avionics Computer Resource (ACR). This research was performed in the context of ongoing standardization efforts, in particular, the work of RTCA committee SC-182, and the recently completed ARINC 653 application executive (APEX) interface standard. We have developed a formal model of partitioning suitable for evaluating the design of an ACR. The model draws from the mathematical modeling techniques developed by the computer security community. This report presents a formulation of partitioning requirements expressed first using conventional mathematical notation, then formalized using the language of SRI'S Prototype Verification System (PVS). The approach is demonstrated on three candidate designs, each an abstraction of features found in real systems.

  18. Second order formalism for spin (1/2) fermions and Compton scattering

    SciTech Connect

    Delgado-Acosta, E. G.; Napsuciale, Mauro; Rodriguez, Simon

    2011-04-01

    We develop a second order formalism for massive spin 1/2 fermions based on the projection over Poincare invariant subspaces in the ((1/2),0)+(0,(1/2)) representation of the homogeneous Lorentz group. Using the U(1){sub em} gauge principle we obtain a second order description for the electromagnetic interactions of a spin 1/2 fermion with two free parameters, the gyromagnetic factor g and a parameter {xi} related to odd-parity Lorentz structures. We calculate Compton scattering in this formalism. In the particular case g=2, {xi}=0, and for states with well-defined parity, we recover Dirac results. In general, we find the correct classical limit and a finite value r{sub c}{sup 2} for the forward differential cross section, independent of the photon energy and of the value of the parameters g and {xi}. The differential cross section vanishes at high energies for all g, {xi} except in the forward direction. The total cross section at high energies vanishes only for g=2, {xi}=0. We argue that this formalism is more convenient than Dirac theory in the description of low energy electromagnetic properties of baryons and illustrate the point with the proton case.

  19. Formal Assurance Arguments: A Solution In Search of a Problem?

    NASA Technical Reports Server (NTRS)

    Graydon, Patrick J.

    2015-01-01

    An assurance case comprises evidence and argument showing how that evidence supports assurance claims (e.g., about safety or security). It is unsurprising that some computer scientists have proposed formalizing assurance arguments: most associate formality with rigor. But while engineers can sometimes prove that source code refines a formal specification, it is not clear that formalization will improve assurance arguments or that this benefit is worth its cost. For example, formalization might reduce the benefits of argumentation by limiting the audience to people who can read formal logic. In this paper, we present (1) a systematic survey of the literature surrounding formal assurance arguments, (2) an analysis of errors that formalism can help to eliminate, (3) a discussion of existing evidence, and (4) suggestions for experimental work to definitively answer the question.

  20. Computational Modeling, Formal Analysis, and Tools for Systems Biology

    PubMed Central

    Bartocci, Ezio; Lió, Pietro

    2016-01-01

    As the amount of biological data in the public domain grows, so does the range of modeling and analysis techniques employed in systems biology. In recent years, a number of theoretical computer science developments have enabled modeling methodology to keep pace. The growing interest in systems biology in executable models and their analysis has necessitated the borrowing of terms and methods from computer science, such as formal analysis, model checking, static analysis, and runtime verification. Here, we discuss the most important and exciting computational methods and tools currently available to systems biologists. We believe that a deeper understanding of the concepts and theory highlighted in this review will produce better software practice, improved investigation of complex biological processes, and even new ideas and better feedback into computer science. PMID:26795950

  1. Fuzzy and rough formal concept analysis: a survey

    NASA Astrophysics Data System (ADS)

    Poelmans, Jonas; Ignatov, Dmitry I.; Kuznetsov, Sergei O.; Dedene, Guido

    2014-02-01

    Formal Concept Analysis (FCA) is a mathematical technique that has been extensively applied to Boolean data in knowledge discovery, information retrieval, web mining, etc. applications. During the past years, the research on extending FCA theory to cope with imprecise and incomplete information made significant progress. In this paper, we give a systematic overview of the more than 120 papers published between 2003 and 2011 on FCA with fuzzy attributes and rough FCA. We applied traditional FCA as a text-mining instrument to 1072 papers mentioning FCA in the abstract. These papers were formatted in pdf files and using a thesaurus with terms referring to research topics, we transformed them into concept lattices. These lattices were used to analyze and explore the most prominent research topics within the FCA with fuzzy attributes and rough FCA research communities. FCA turned out to be an ideal metatechnique for representing large volumes of unstructured texts.

  2. Design Strategy for a Formally Verified Reliable Computing Platform

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Caldwell, James L.; DiVito, Ben L.

    1991-01-01

    This paper presents a high-level design for a reliable computing platform for real-time control applications. The design tradeoffs and analyses related to the development of a formally verified reliable computing platform are discussed. The design strategy advocated in this paper requires the use of techniques that can be completely characterized mathematically as opposed to more powerful or more flexible algorithms whose performance properties can only be analyzed by simulation and testing. The need for accurate reliability models that can be related to the behavior models is also stressed. Tradeoffs between reliability and voting complexity are explored. In particular, the transient recovery properties of the system are found to be fundamental to both the reliability analysis as well as the "correctness" models.

  3. Formal Methods Specification and Analysis Guidebook for the Verification of Software and Computer Systems. Volume 2; A Practitioner's Companion

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This guidebook, the second of a two-volume series, is intended to facilitate the transfer of formal methods to the avionics and aerospace community. The 1st volume concentrates on administrative and planning issues [NASA-95a], and the second volume focuses on the technical issues involved in applying formal methods to avionics and aerospace software systems. Hereafter, the term "guidebook" refers exclusively to the second volume of the series. The title of this second volume, A Practitioner's Companion, conveys its intent. The guidebook is written primarily for the nonexpert and requires little or no prior experience with formal methods techniques and tools. However, it does attempt to distill some of the more subtle ingredients in the productive application of formal methods. To the extent that it succeeds, those conversant with formal methods will also nd the guidebook useful. The discussion is illustrated through the development of a realistic example, relevant fragments of which appear in each chapter. The guidebook focuses primarily on the use of formal methods for analysis of requirements and high-level design, the stages at which formal methods have been most productively applied. Although much of the discussion applies to low-level design and implementation, the guidebook does not discuss issues involved in the later life cycle application of formal methods.

  4. General formalism for the efficient calculation of derivatives of EM frequency-domain responses and derivatives of the misfit

    NASA Astrophysics Data System (ADS)

    Pankratov, Oleg; Kuvshinov, Alexei

    2010-04-01

    Electromagnetic (EM) studies of the Earth have advanced significantly over the past few years. This progress was driven, in particular, by new developments in the methods of 3-D inversion of EM data. Due to the large scale of the 3-D EM inverse problems, iterative gradient-type methods have mostly been employed. In these methods one has to calculate multiple times the gradient of the penalty function-a sum of misfit and regularization terms-with respect to the model parameters. However, even with modern computational capabilities the straightforward calculation of the misfit gradients based on numerical differentiation is extremely time consuming. Much more efficient and elegant way to calculate the gradient of the misfit is provided by the so-called `adjoint' approach. This is now widely used in many 3-D numerical schemes for inverting EM data of different types and origin. It allows the calculation of the misfit gradient for the price of only a few additional forward calculations. In spite of its popularity we did not find in the literature any general description of the approach, which would allow researchers to apply this methodology in a straightforward manner to their scenario of interest. In the paper, we present formalism for the efficient calculation of the derivatives of EM frequency-domain responses and the derivatives of the misfit with respect to variations of 3-D isotropic/anisotropic conductivity. The approach is rather general; it works with single-site responses, multisite responses and responses that include spatial derivatives of EM field. The formalism also allows for various types of parametrization of the 3-D conductivity distribution. Using this methodology one can readily obtain appropriate formulae for the specific sounding methods. To illustrate the concept we provide such formulae for a number of EM techniques: geomagnetic depth sounding (GDS), conventional and generalized magnetotellurics, the magnetovariational method, horizontal

  5. Canonical formalism for coupled beam optics

    SciTech Connect

    Kheifets, S.A.

    1989-09-01

    Beam optics of a lattice with an inter-plane coupling is treated using canonical Hamiltonian formalism. The method developed is equally applicable both to a circular (periodic) machine and to an open transport line. A solution of the equation of a particle motion (and correspondingly transfer matrix between two arbitrary points of the lattice) are described in terms of two amplitude functions (and their derivatives and corresponding phases of oscillations) and four coupling functions, defined by a solution of the system of the first-order nonlinear differential equations derived in the paper. Thus total number of independent parameters is equal to ten. 8 refs.

  6. The formal verification of generic interpreters

    NASA Technical Reports Server (NTRS)

    Windley, P.; Levitt, K.; Cohen, G. C.

    1991-01-01

    The task assignment 3 of the design and validation of digital flight control systems suitable for fly-by-wire applications is studied. Task 3 is associated with formal verification of embedded systems. In particular, results are presented that provide a methodological approach to microprocessor verification. A hierarchical decomposition strategy for specifying microprocessors is also presented. A theory of generic interpreters is presented that can be used to model microprocessor behavior. The generic interpreter theory abstracts away the details of instruction functionality, leaving a general model of what an interpreter does.

  7. BRST and the pure spinor formalism

    SciTech Connect

    Garcia, J. Antonio

    2008-03-06

    The aim of this talk is to show the relation between the standard BRST approach of the GS superstring with the quantization technics used in the pure spinor approach to superstring. To that end we will use the Batalin-Fradkin-Tyutin (BFT) conversion program of second class constraints to first class constraints in the GS superstring using light cone coordinates. By applying this systematic procedure we were able to obtain a gauge system that is equivalent to the recent model proposed in [1] to relate the GS superstring to the pure spinor formalism.

  8. Formal Aspects of Human-Automation Interaction

    NASA Technical Reports Server (NTRS)

    Degani, Asaf; Heymann, Michael; Moodi, Michael; Remington, Roger (Technical Monitor)

    1998-01-01

    While new versions of automated control systems such as flight guidance systems are introduced at a rapid pace, it is widely recognized that user interaction with these machines is increasingly problematic. One cause for this difficulty that is commonly cited in the literature, is the discrepancy between the machine's behavior and the operator's (e.g., pilot) expectations. This paper discusses a formal approach to the analysis of operator's interaction with complex automated control systems. We focus attention on the issue of interface correctness; that is, on the question whether the display provides adequate information about the machine's configurations (states, modes, and associated parameters) and transitions, so as to enable the operator to successfully perform the specified set of tasks. To perform the analysis several assumptions are made: (1) A complete formal model of the machine's behavior is available (e.g., as a state transition system, or as a hybrid-machine); (2) A specification of operator's tasks is available and can be formally described (e.g., the reliable and predictable transition between activities involved in executing a climb to a new altitude); (3) The pilot is well trained and has a correct 'mental' model of the machine's response-map. By 'comparing' the machine's model with the set of operator's tasks we formally (i.e., mathematically) evaluate two questions: 1) does the machine's output interface (display) enable the operator to determine, unambiguously, what the current configuration (e.g., mode) of the machine is, and 2) does the display enable the operator to determine, unambiguously, what the next configuration of the machine will be, in response to a specified interaction by the operator (e.g., engaging a mode or changing a parameter such as a speed or target altitude). This paper describes a methodology for conducting such an evaluation using examples from automated flight control systems of modem 'glass cockpit' jetliners

  9. Representations of spacetime: Formalism and ontological commitment

    NASA Astrophysics Data System (ADS)

    Bain, Jonathan Stanley

    This dissertation consists of two parts. The first is on the relation between formalism and ontological commitment in the context of theories of spacetime, and the second is on scientific realism. The first part begins with a look at how the substantivalist/relationist debate over the ontological status of spacetime has been influenced by a particular mathematical formalism, that of tensor analysis on differential manifolds (TADM). This formalism has motivated the substantivalist position known as manifold substantivalism. Chapter 1 focuses on the hole argument which maintains that manifold substantivalism is incompatible with determinism. I claim that the realist motivations underlying manifold substantivalism can be upheld, and the hole argument avoided, by adopting structural realism with respect to spacetime. In this context, this is the claim that it is the structure that spacetime points enter into that warrants belief and not the points themselves. In Chapter 2, an elimination principle is defined by means of which a distinction can be made between surplus structure and essential structure with respect to formulations of a theory in two distinct mathematical formulations and some prior ontological commitments. This principle is then used to demonstrate that manifold points may be considered surplus structure in the formulation of field theories. This suggests that, if we are disposed to read field theories literally, then, at most, it should be the essential structure common to all alternative formulations of such theories that should be taken literally. I also investigate how the adoption of alternative formalisms informs other issues in the philosophy of spacetime. Chapter 3 offers a realist position which takes a semantic moral from the preceding investigation and an epistemic moral from work done on reliability. The semantic moral advises us to read only the essential structure of our theories literally. The epistemic moral shows us that such structure

  10. Some Aspects of the Symbolic Manipulation of Computer Descriptions

    DTIC Science & Technology

    1974-07-01

    Given a desired macnme described .r terms of some specification language, and g^ven a space of machines def.ned by a class of Register Transfer...ISP, design it in terms of Foster Transfer level modules. Formally they may seem iden^cal. but the design spaces looi. quite d.nerent. 6) Mf... spacing is needed by the design automation system to produce a wiring list. Hence there is information contained in the computer description that is

  11. 19 CFR 128.25 - Formal entry procedures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Formal entry procedures. 128.25 Section 128.25... TREASURY EXPRESS CONSIGNMENTS Procedures § 128.25 Formal entry procedures. Formal entry, as provided for under 19 U.S.C. 1484 in parts 141, 142, and 143 (except for subpart C), of this chapter, is required...

  12. 20 CFR 702.336 - Formal hearings; new issues.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Formal hearings; new issues. 702.336 Section... Adjudication Procedures Formal Hearings § 702.336 Formal hearings; new issues. (a) If, during the course of the... considered, the hearing may be expanded to include the new issue. If in the opinion of the administrative...

  13. 40 CFR 35.938-4 - Formal advertising.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Formal advertising. 35.938-4 Section 35... advertising. Each contract shall be awarded after formal advertising, unless negotiation is permitted in accordance with § 35.936-18. Formal advertising shall be in accordance with the following: (a)...

  14. 40 CFR 35.938-4 - Formal advertising.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Formal advertising. 35.938-4 Section 35... advertising. Each contract shall be awarded after formal advertising, unless negotiation is permitted in accordance with § 35.936-18. Formal advertising shall be in accordance with the following: (a)...

  15. 40 CFR 35.938-4 - Formal advertising.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Formal advertising. 35.938-4 Section 35... advertising. Each contract shall be awarded after formal advertising, unless negotiation is permitted in accordance with § 35.936-18. Formal advertising shall be in accordance with the following: (a)...

  16. 40 CFR 35.938-4 - Formal advertising.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Formal advertising. 35.938-4 Section 35... advertising. Each contract shall be awarded after formal advertising, unless negotiation is permitted in accordance with § 35.936-18. Formal advertising shall be in accordance with the following: (a)...

  17. "Passing It On": Beyond Formal or Informal Pedagogies

    ERIC Educational Resources Information Center

    Cain, Tim

    2013-01-01

    Informal pedagogies are a subject of debate in music education, and there is some evidence of teachers abandoning formal pedagogies in favour of informal ones. This article presents a case of one teacher's formal pedagogy and theorises it by comparing it with a case of informal pedagogy. The comparison reveals affordances of formal pedagogies…

  18. How External Institutions Penetrate Schools through Formal and Informal Leaders

    ERIC Educational Resources Information Center

    Sun, Min; Frank, Kenneth A.; Penuel, William R.; Kim, Chong Min

    2013-01-01

    Purposes: This study investigates the role of formal and informal leaders in the diffusion of external reforms into schools and to teachers' practices. Formal leaders are designated by their roles in the formal organization of the school (e.g., principals, department chairs, and instructional coaches) and informal leaders refer to those who do not…

  19. 40 CFR 35.938-4 - Formal advertising.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Formal advertising. 35.938-4 Section 35... advertising. Each contract shall be awarded after formal advertising, unless negotiation is permitted in accordance with § 35.936-18. Formal advertising shall be in accordance with the following: (a)...

  20. Formal linguistics as a cue to demographic history.

    PubMed

    Longobardi, Giuseppe; Ceolin, Andrea; Ecay, Aaron; Ghirotto, Silvia; Guardiano, Cristina; Irimia, Monica-Alexandrina; Michelioudakis, Dimitris; Radkevich, Nina; Pettener, Davide; Luiselli, Donata; Barbujani, Guido

    2016-06-20

    Beyond its theoretical success, the development of molecular genetics has brought about the possibility of extraordinary progress in the study of classification and in the inference of the evolutionary history of many species and populations. A major step forward was represented by the availability of extremely large sets of molecular data suited to quantitative and computational treatments. In this paper, we argue that even in cognitive sciences, purely theoretical progress in a discipline such as linguistics may have analogous impact. Thus, exactly on the model of molecular biology, we propose to unify two traditionally unrelated lines of linguistic investigation: 1) the formal study of syntactic variation (parameter theory) in the biolinguistic program; 2) the reconstruction of relatedness among languages (phylogenetic taxonomy). The results of our linguistic analysis have thus been plotted against data from population genetics and the correlations have turned out to be largely significant: given a non-trivial set of languages/populations, the description of their variation provided by the comparison of systematic parametric analysis and molecular anthropology informatively recapitulates their history and relationships. As a result, we can claim that the reality of some parametric model of the language faculty and language acquisition/transmission (more broadly of generative grammar) receives strong and original support from its historical heuristic power. Then, on these grounds, we can begin testing Darwin's prediction that, when properly generated, the trees of human populations and of their languages should eventually turn out to be significantly parallel.

  1. Extended Cahill-Glauber formalism for finite-dimensional spaces. II. Applications in quantum tomography and quantum teleportation

    SciTech Connect

    Marchiolli, Marcelo A.; Ruzzi, Maurizio; Galetti, Diogenes

    2005-10-15

    By means of a mod(N)-invariant operator basis, s-parametrized phase-space functions associated with bounded operators in a finite-dimensional Hilbert space are introduced in the context of the extended Cahill-Glauber formalism, and their properties are discussed in details. The discrete Glauber-Sudarshan, Wigner, and Husimi functions emerge from this formalism as specific cases of s-parametrized phase-space functions where, in particular, a hierarchical process among them is promptly established. In addition, a phase-space description of quantum tomography and quantum teleportation is presented and new results are obtained.

  2. Formal analytical modeling of blog content as personal narrative

    NASA Astrophysics Data System (ADS)

    Coombs, Michael J.; Jaenisch, Holger M.; Handley, James W.

    2008-04-01

    This paper contrasts two techniques for analyzing blog content and making use of this information to model blog content. One method uses classical text content and analysis presented for human interpretation. The second method relies on a data mined list of descriptive words characterizing the blogs. We examine the use of different data mining tools, Kryltech's "Subject Search Summarizer", Leximancer, and QUEST, to provide orthogonal and independently generated key word lists. These lists are then converted into Data Models, enabling mathematical modeling of blog content.

  3. Versatile Formal Methods Applied to Quantum Information.

    SciTech Connect

    Witzel, Wayne; Rudinger, Kenneth Michael; Sarovar, Mohan

    2015-11-01

    Using a novel formal methods approach, we have generated computer-veri ed proofs of major theorems pertinent to the quantum phase estimation algorithm. This was accomplished using our Prove-It software package in Python. While many formal methods tools are available, their practical utility is limited. Translating a problem of interest into these systems and working through the steps of a proof is an art form that requires much expertise. One must surrender to the preferences and restrictions of the tool regarding how mathematical notions are expressed and what deductions are allowed. Automation is a major driver that forces restrictions. Our focus, on the other hand, is to produce a tool that allows users the ability to con rm proofs that are essentially known already. This goal is valuable in itself. We demonstrate the viability of our approach that allows the user great exibility in expressing state- ments and composing derivations. There were no major obstacles in following a textbook proof of the quantum phase estimation algorithm. There were tedious details of algebraic manipulations that we needed to implement (and a few that we did not have time to enter into our system) and some basic components that we needed to rethink, but there were no serious roadblocks. In the process, we made a number of convenient additions to our Prove-It package that will make certain algebraic manipulations easier to perform in the future. In fact, our intent is for our system to build upon itself in this manner.

  4. Formalism and Interpretation in Quantum Theory

    NASA Astrophysics Data System (ADS)

    Wilce, Alexander

    2010-04-01

    Quantum Mechanics can be viewed as a linear dynamical theory having a familiar mathematical framework but a mysterious probabilistic interpretation, or as a probabilistic theory having a familiar interpretation but a mysterious formal framework. These points of view are usually taken to be somewhat in tension with one another. The first has generated a vast literature aiming at a “realistic” and “collapse-free” interpretation of quantum mechanics that will account for its statistical predictions. The second has generated an at least equally large literature aiming to derive, or at any rate motivate, the formal structure of quantum theory in probabilistically intelligible terms. In this paper I explore, in a preliminary way, the possibility that these two programmes have something to offer one another. In particular, I show that a version of the measurement problem occurs in essentially any non-classical probabilistic theory, and ask to what extent various interpretations of quantum mechanics continue to make sense in such a general setting. I make a start on answering this question in the case of a rudimentary version of the Everett interpretation.

  5. Generalized Boltzmann formalism for oscillating neutrinos

    SciTech Connect

    Strack, P.; Burrows, A.

    2005-05-01

    In the standard approaches to neutrino transport in the simulation of core-collapse supernovas, one will often start from the classical Boltzmann equation for the neutrino's spatial, temporal, and spectral evolution. For each neutrino species, and its antiparticle, the classical density in phase space, or the associated specific intensity, will be calculated as a function of time. The neutrino radiation is coupled to matter by source and sink terms on the 'right-hand side' of the transport equation and together with the equations of hydrodynamics this set of coupled partial differential equations for classical densities describes, in principle, the evolution of core collapse and explosion. However, with the possibility of neutrino oscillations between species, a purely quantum-physical effect, how to generalize this set of Boltzmann equations for classical quantities to reflect oscillation physics has not been clear. To date, the formalisms developed have retained the character of quantum operator physics involving complex quantities and have not been suitable for easy incorporation into standard supernova codes. In this paper, we derive generalized Boltzmann equations for quasiclassical, real-valued phase-space densities that retain all the standard oscillation phenomenology, including the matter-enhanced resonant flavor conversion (Mikheev-Smirnov-Wolfenstein effect), neutrino self-interactions, and the interplay between decohering matter coupling and flavor oscillations. With this formalism, any code(s) that can now handle the solution of the classical Boltzmann or transport equation can easily be generalized to include neutrino oscillations in a quantum-physically consistent fashion.

  6. Perturbative method for the derivation of quantum kinetic theory based on closed-time-path formalism.

    PubMed

    Koide, Jun

    2002-02-01

    Within the closed-time-path formalism, a perturbative method is presented, which reduces the microscopic field theory to the quantum kinetic theory. In order to make this reduction, the expectation value of a physical quantity must be calculated under the condition that the Wigner distribution function is fixed, because it is the independent dynamical variable in the quantum kinetic theory. It is shown that when a nonequilibrium Green function in the form of the generalized Kadanoff-Baym ansatz is utilized, this condition appears as a cancellation of a certain part of contributions in the diagrammatic expression of the expectation value. Together with the quantum kinetic equation, which can be derived in the closed-time-path formalism, this method provides a basis for the kinetic-theoretical description.

  7. Higher-order generalized hydrodynamics: Foundations within a nonequilibrium statistical ensemble formalism.

    PubMed

    Silva, Carlos A B; Rodrigues, Clóves G; Ramos, J Galvão; Luzzi, Roberto

    2015-06-01

    Construction, in the framework of a nonequilibrium statistical ensemble formalism, of a higher-order generalized hydrodynamics, also referred to as mesoscopic hydrothermodynamics, that is, covering phenomena involving motion of fluids displaying variations short in space and fast in time-unrestricted values of Knudsen numbers, is presented. In that way, an approach is provided enabling the coupling and simultaneous treatment of the kinetics and hydrodynamic levels of descriptions. It is based on a complete thermostatistical approach in terms of the densities of matter and energy and their fluxes of all orders covering systems arbitrarily driven away from equilibrium. The set of coupled nonlinear integrodifferential hydrodynamic equations is derived. They are the evolution equations of the Gradlike moments of all orders, derived from a generalized kinetic equation built in the framework of the nonequilibrium statistical ensemble formalism. For illustration, the case of a system of particles embedded in a fluid acting as a thermal bath is fully described. The resulting enormous set of coupled evolution equations is of unmanageable proportions, thus requiring in practice to introduce an appropriate description using the smallest possible number of variables. We have obtained a hierarchy of Maxwell times, associated to the set of all the higher-order fluxes, which have a particular relevance in the process of providing criteria for establishing the contraction of description.

  8. Günther's formalism (κ-symplectic formalism) in classical field theory: Skinner-Rusk approach and the evolution operator

    NASA Astrophysics Data System (ADS)

    Rey, Angel M.; Román-Roy, Narciso; Salgado, Modesto

    2005-05-01

    The first aim of this paper is to extend the Skinner-Rusk formalism on classical mechanics for first-order field theories. The second is to generalize the definition and properties of the evolution K-operator on classical mechanics for first-order field theories using in both cases Günther's formalism (k-symplectic formalism).

  9. Indigenous Knowledge and Education from the Quechua Community to School: Beyond the Formal/Non-Formal Dichotomy

    ERIC Educational Resources Information Center

    Sumida Huaman, Elizabeth; Valdiviezo, Laura Alicia

    2014-01-01

    In this article, we propose to approach Indigenous education beyond the formal/non-formal dichotomy. We argue that there is a critical need to conscientiously include Indigenous knowledge in education processes from the school to the community; particularly, when formal systems exclude Indigenous cultures and languages. Based on ethnographic…

  10. Guidance for Using Formal Methods in a Certification Context

    NASA Technical Reports Server (NTRS)

    Brown, Duncan; Delseny, Herve; Hayhurst, Kelly; Wiels, Virginie

    2010-01-01

    This paper discusses some of the challenges to using formal methods in a certification context and describes the effort by the Formal Methods Subgroup of RTCA SC-205/EUROCAE WG-71 to propose guidance to make the use of formal methods a recognized approach. This guidance, expected to take the form of a Formal Methods Technical Supplement to DO-178C/ED-12C, is described, including the activities that are needed when using formal methods, new or modified objectives with respect to the core DO-178C/ED-12C document, and evidence needed for meeting those objectives.

  11. Full-body gestures and movements recognition: user descriptive and unsupervised learning approaches in GDL classifier

    NASA Astrophysics Data System (ADS)

    Hachaj, Tomasz; Ogiela, Marek R.

    2014-09-01

    Gesture Description Language (GDL) is a classifier that enables syntactic description and real time recognition of full-body gestures and movements. Gestures are described in dedicated computer language named Gesture Description Language script (GDLs). In this paper we will introduce new GDLs formalisms that enable recognition of selected classes of movement trajectories. The second novelty is new unsupervised learning method with which it is possible to automatically generate GDLs descriptions. We have initially evaluated both proposed extensions of GDL and we have obtained very promising results. Both the novel methodology and evaluation results will be described in this paper.

  12. Applying formal methods and object-oriented analysis to existing flight software

    NASA Technical Reports Server (NTRS)

    Cheng, Betty H. C.; Auernheimer, Brent

    1993-01-01

    Correctness is paramount for safety-critical software control systems. Critical software failures in medical radiation treatment, communications, and defense are familiar to the public. The significant quantity of software malfunctions regularly reported to the software engineering community, the laws concerning liability, and a recent NRC Aeronautics and Space Engineering Board report additionally motivate the use of error-reducing and defect detection software development techniques. The benefits of formal methods in requirements driven software development ('forward engineering') is well documented. One advantage of rigorously engineering software is that formal notations are precise, verifiable, and facilitate automated processing. This paper describes the application of formal methods to reverse engineering, where formal specifications are developed for a portion of the shuttle on-orbit digital autopilot (DAP). Three objectives of the project were to: demonstrate the use of formal methods on a shuttle application, facilitate the incorporation and validation of new requirements for the system, and verify the safety-critical properties to be exhibited by the software.

  13. Dual-Lagrangian description adapted to quantum optics in dispersive and dissipative dielectric media

    NASA Astrophysics Data System (ADS)

    Drezet, Aurélien

    2016-11-01

    We develop a dual description of quantum optics adapted to dielectric systems without magnetic property. Our formalism, which is shown to be equivalent to the standard one within some dipolar approximations discussed in the article, is applied to the description of polaritons in dielectric media. We show that the dual formalism leads to the Huttner-Barnett equations [B. Huttner and S. M. Barnett, Phys. Rev. A 46, 4306 (1992), 10.1103/PhysRevA.46.4306] for QED in dielectric systems. More generally, we discuss the role of electromagnetic duality in the quantization procedure for optical systems and derive the structure of the dynamical laws in the various representations.

  14. Teaching Descriptive Style.

    ERIC Educational Resources Information Center

    Brashers, H. C.

    1968-01-01

    As the inexperienced writer becomes aware of the issues involved in the composition of effective descriptive prose, he also develops a consistent control over his materials. The persona he chooses, if coherently thought out, can function as an index of many choices, helping him to manipulate the tone, intent, and mood of this style; to regulate…

  15. Andrew integrated reservoir description

    SciTech Connect

    Todd, S.P.

    1996-12-31

    The Andrew field is an oil and gas accumulation in Palaeocene deep marine sands in the Central North Sea. It is currently being developed with mainly horizontal oil producers. Because of the field`s relatively small reserves (mean 118 mmbbls), the performance of each of the 10 or so horizontal wells is highly important. Reservoir description work at sanction time concentrated on supporting the case that the field could be developed commercially with the minimum number of wells. The present Integrated Reservoir Description (IRD) is focussed on delivering the next level of detail that will impact the understanding of the local reservoir architecture and dynamic performance of each well. Highlights of Andrew IRD Include: (1) Use of a Reservoir Uncertainty Statement (RUS) developed at sanction time to focus the descriptive effort of both asset, support and contract petrotechnical staff, (2) High resolution biostratigraphic correlation to support confident zonation of the reservoir, (3) Detailed sedimentological analysis of the core including the use of dipmeter to interpret channel/sheet architecture to provide new insights into reservoir heterogeneity; (4) Integrated petrographical and petrophysical investigation of the controls on Sw-Height and relative permeability of water; (5) Fluids description using oil geochemistry and Residual Salt Analysis Sr isotope studies. Andrew IRD has highlighted several important risks to well performance, including the influence of more heterolithic intervals on gas breakthrough and the controls on water coning exerted by suppressed water relative permeability in the transition zone.

  16. Andrew integrated reservoir description

    SciTech Connect

    Todd, S.P.

    1996-01-01

    The Andrew field is an oil and gas accumulation in Palaeocene deep marine sands in the Central North Sea. It is currently being developed with mainly horizontal oil producers. Because of the field's relatively small reserves (mean 118 mmbbls), the performance of each of the 10 or so horizontal wells is highly important. Reservoir description work at sanction time concentrated on supporting the case that the field could be developed commercially with the minimum number of wells. The present Integrated Reservoir Description (IRD) is focussed on delivering the next level of detail that will impact the understanding of the local reservoir architecture and dynamic performance of each well. Highlights of Andrew IRD Include: (1) Use of a Reservoir Uncertainty Statement (RUS) developed at sanction time to focus the descriptive effort of both asset, support and contract petrotechnical staff, (2) High resolution biostratigraphic correlation to support confident zonation of the reservoir, (3) Detailed sedimentological analysis of the core including the use of dipmeter to interpret channel/sheet architecture to provide new insights into reservoir heterogeneity; (4) Integrated petrographical and petrophysical investigation of the controls on Sw-Height and relative permeability of water; (5) Fluids description using oil geochemistry and Residual Salt Analysis Sr isotope studies. Andrew IRD has highlighted several important risks to well performance, including the influence of more heterolithic intervals on gas breakthrough and the controls on water coning exerted by suppressed water relative permeability in the transition zone.

  17. Description of a new technique for repairing chronic type B dissections that involve visceral branches being fed by both true and false lumen by using both lumens as conduits

    PubMed Central

    Anderson, Joe; Remund, Tyler; Pohlson, Katie

    2016-01-01

    Here we present three cases performed using a novel technique where aortic flow is compartmentalized proximal to the target vessels through a physician-modified endograft. The visceral segment is then further compartmentalized by the use of another physician modified endograft. By compartmentalizing the flow proximal to the visceral segment, both the true lumen and false lumen can be used as conduits for coextensive bridging stent grafts. Overall, patients have tolerated this procedure extremely well, and while further study and follow-up must be conducted, this procedure could offer a reasonable long-term solution to thoracoabdominal aortic aneurysms complicated by dissection. PMID:25972031

  18. Formalisms for Specifying Markovian Population Models

    NASA Astrophysics Data System (ADS)

    Henzinger, Thomas A.; Jobstmann, Barbara; Wolf, Verena

    We compare several languages for specifying Markovian population models such as queuing networks and chemical reaction networks. These languages —matrix descriptions, stochastic Petri nets, stoichiometric equations, stochastic process algebras, and guarded command models— all describe continuous-time Markov chains, but they differ according to important properties, such as compositionality, expressiveness and succinctness, executability, ease of use, and the support they provide for checking the well-formedness of a model and for analyzing a model.

  19. Information Superiority via Formal Concept Analysis

    NASA Astrophysics Data System (ADS)

    Koester, Bjoern; Schmidt, Stefan E.

    This chapter will show how to get more mileage out of information. To achieve that, we first start with an introduction to the fundamentals of Formal Concept Analysis (FCA). FCA is a highly versatile field of applied lattice theory, which allows hidden relationships to be uncovered in relational data. Moreover, FCA provides a distinguished supporting framework to subsequently find and fill information gaps in a systematic and rigorous way. In addition, we would like to build bridges via a universal approach to other communities which can be related to FCA in order for other research areas to benefit from a theory that has been elaborated for more than twenty years. Last but not least, the essential benefits of FCA will be presented algorithmically as well as theoretically by investigating a real data set from the MIPT Terrorism Knowledge Base and also by demonstrating an application in the field of Web Information Retrieval and Web Intelligence.

  20. Whatever Happened to Formal Methods for Security?

    PubMed

    Voas, J; Schaffer, K

    2016-08-01

    We asked 7 experts 7 questions to find out what has occurred recently in terms of applying formal methods (FM) to security-centric, cyber problems. We are continually reminded of the 1996 paper by Tony Hoare "How did Software Get So Reliable Without Proof?" [1] In that vein, how did we get so insecure with proof? Given daily press announcements concerning new malware, data breaches, and privacy loss, is FM still relevant or was it ever? Our experts answered with unique personal insights. We were curious as to whether this successful methodology in "safety-critical" has succeeded as well for today's "build it, hack it, patch it" mindset. Our experts were John McLean (Naval Research Labs), Paul Black (National Institute of Standards and Technology), Karl Levitt (University of California at Davis), Joseph Williams (CloudEconomist.Com), Connie Heitmeyer (Naval Research Labs), Eugene Spafford (Purdue University), and Joseph Kiniry (Galois, Inc.). The questions and responses follow.

  1. Thermodynamic consistency of the interaction parameter formalism

    NASA Astrophysics Data System (ADS)

    Srikanth, S.; Jacob, K. T.

    1988-04-01

    The apparent contradiction between the exact nature of the interaction parameter formalism as presented by Lupis and Elliott and the inconsistencies discussed recently by Pelton and Bale arise from the truncation of the Maclaurin series in the latter treatment. The truncation removes the exactness of the expression for the logarithm of the activity coefficient of a solute in a multi-component system. The integrals are therefore path dependent. Formulae for integration along paths of constant Xi, or X i/Xj are presented. The expression for In γsolvent given by Pelton and Bale is valid only in the limit that the mole fraction of solvent tends to one. The truncation also destroys the general relations between interaction parameters derived by Lupis and Elliott. For each specific choice of parameters special relationships are obtained between interaction parameters.

  2. The stable computation of formal orthogonal polynomials

    NASA Astrophysics Data System (ADS)

    Beckermann, Bernhard

    1996-12-01

    For many applications - such as the look-ahead variants of the Lanczos algorithm - a sequence of formal (block-)orthogonal polynomials is required. Usually, one generates such a sequence by taking suitable polynomial combinations of a pair of basis polynomials. These basis polynomials are determined by a look-ahead generalization of the classical three term recurrence, where the polynomial coefficients are obtained by solving a small system of linear equations. In finite precision arithmetic, the numerical orthogonality of the polynomials depends on a good choice of the size of the small systems; this size is usually controlled by a heuristic argument such as the condition number of the small matrix of coefficients. However, quite often it happens that orthogonality gets lost.

  3. Geodesic Acoustic Propagation and Ballooning Mode Formalism

    NASA Astrophysics Data System (ADS)

    Li, M. B.; Diamond, P. H.; Young, G. G.; Arakawa, M.

    2005-10-01

    Relevance of ballooning formalism (BMF) in nonlinear interaction of toroidal electromagnetic drift waves in the presence of zonal flows and Geodesic Acoustic Oscillation (GAO) is critically examined from a physical argument of radial propagation of wave packets. To achieve the quasi-translational invariance of poloidal harmonics which is necessary for the BMF, the geodesic curvature induced transfer [1] of fluctuation energy in radial direction should occur faster than the time scale of physical interest. Of course, this does not happen necessarily in drift-Alfven (DALF) turbulence simulations [2]. This observation casts considerable doubts on the applicability of various codes based on the BMF concept to nonlinear electromagnetic problems. [1] B. Scott, Phys. Letters A 320 (2003) 53. [2] B. Scott, New J. Phys 7 (2005) 92.

  4. Minimal dynamical description of eye movements

    NASA Astrophysics Data System (ADS)

    Specht, Juan I.; Dimieri, Leonardo; Urdapilleta, Eugenio; Gasaneo, Gustavo

    2017-02-01

    In this paper we have addressed the question of whether a simple set of functions being the solution of a model, namely the damped harmonic oscillator with a general driving force, can satisfactorily describe data corresponding to ocular movements produced during a visual search task. Taking advantage of its mathematical tractability, we first focused on the simplest driving force compatible to the experimental data, a step-like activation. Under this hypothesis we were able to further simplify the system, once data from several experiments were fitted, producing an essentially parameter-free model that we plan to use in future applications. To increase the quality of the description of individual movements, we expanded the complexity in the forcing term and solved the inverse problem by using a proper mathematical formalism. Furthermore, additional terms, those arising from ocular drift and tremor, may be included within the same mathematical approach.

  5. A formal language for the specification and verification of synchronous and asynchronous circuits

    NASA Technical Reports Server (NTRS)

    Russinoff, David M.

    1993-01-01

    A formal hardware description language for the intended application of verifiable asynchronous communication is described. The language is developed within the logical framework of the Nqthm system of Boyer and Moore and is based on the event-driven behavioral model of VHDL, including the basic VHDL signal propagation mechanisms, the notion of simulation deltas, and the VHDL simulation cycle. A core subset of the language corresponds closely with a subset of VHDL and is adequate for the realistic gate-level modeling of both combinational and sequential circuits. Various extensions to this subset provide means for convenient expression of behavioral circuit specifications.

  6. Unified Formalism of Andreev Reflection at a Ferromagnet/Superconductor Interface

    NASA Astrophysics Data System (ADS)

    Chen, T. Y.; Tesanovic, Z.; Chien, C. L.

    2012-10-01

    We present a unified formalism of Andreev reflection of a partial polarized current at a ferromagnet/superconductor interface instead of assuming a linear combination of unpolarized and polarized currents. The Andreev reflection is limited by the states of minority spins and the extra majority spins become evanescent wave. We further study the effects of spin polarization, inelastic scattering, and interfacial scattering on the Andreev reflection, normal reflection, and transmitted probabilities in equilibrium as well as under a bias. Our model, which reduces to those of Blonder, Tinkham, and Klapwijk, Mazin, and Dynes in three limiting cases, provides a significantly better description of the experimental results.

  7. Nondestructive evaluation technique guide

    NASA Technical Reports Server (NTRS)

    Vary, A.

    1973-01-01

    A total of 70 individual nondestructive evaluation (NDE) techniques are described. Information is presented that permits ease of comparison of the merits and limitations of each technique with respect to various NDE problems. An NDE technique classification system is presented. It is based on the system that was adopted by the National Materials Advisory Board (NMAB). The classification system presented follows the NMAB system closely with the exception of additional categories that have been added to cover more advanced techniques presently in use. The rationale of the technique is explained. The format provides for a concise description of each technique, the physical principles involved, objectives of interrogation, example applications, limitations of each technique, a schematic illustration, and key reference material. Cross-index tabulations are also provided so that particular NDE problems can be referred to appropriate techniques.

  8. Bilateral removal of the mandibular and medial retropharyngeal lymph nodes through a single ventral midline incision for staging of head and neck cancers in dogs: a description of surgical technique.

    PubMed

    Green, K; Boston, S E

    2017-03-01

    Currently, there is no standard protocol for removal of regional lymph nodes for the staging of head and neck cancers in dogs. Palpation and fine needle aspiration of mandibular lymph nodes are most commonly performed for staging of head and neck cancers. Although cytology is commonly performed for staging of head and neck, cancers histopathology is required for definitive lymph node staging. When regional lymph node biopsy is performed, mandibular lymph nodes are most commonly sampled due to their accessibility. The medial retropharyngeal lymph nodes may be the most relevant draining lymph node of the head and neck, but they are not routinely sampled due to their anatomic location medial to the salivary glands. The technique described here will allow for a standardized surgical approach for the efficient removal of both mandibular and medial retropharyngeal lymph nodes for staging of head and neck tumours via a single ventral midline approach.

  9. From Informal Safety-Critical Requirements to Property-Driven Formal Validation

    NASA Technical Reports Server (NTRS)

    Cimatti, Alessandro; Roveri, Marco; Susi, Angelo; Tonetta, Stefano

    2008-01-01

    Most of the efforts in formal methods have historically been devoted to comparing a design against a set of requirements. The validation of the requirements themselves, however, has often been disregarded, and it can be considered a largely open problem, which poses several challenges. The first challenge is given by the fact that requirements are often written in natural language, and may thus contain a high degree of ambiguity. Despite the progresses in Natural Language Processing techniques, the task of understanding a set of requirements cannot be automatized, and must be carried out by domain experts, who are typically not familiar with formal languages. Furthermore, in order to retain a direct connection with the informal requirements, the formalization cannot follow standard model-based approaches. The second challenge lies in the formal validation of requirements. On one hand, it is not even clear which are the correctness criteria or the high-level properties that the requirements must fulfill. On the other hand, the expressivity of the language used in the formalization may go beyond the theoretical and/or practical capacity of state-of-the-art formal verification. In order to solve these issues, we propose a new methodology that comprises of a chain of steps, each supported by a specific tool. The main steps are the following. First, the informal requirements are split into basic fragments, which are classified into categories, and dependency and generalization relationships among them are identified. Second, the fragments are modeled using a visual language such as UML. The UML diagrams are both syntactically restricted (in order to guarantee a formal semantics), and enriched with a highly controlled natural language (to allow for modeling static and temporal constraints). Third, an automatic formal analysis phase iterates over the modeled requirements, by combining several, complementary techniques: checking consistency; verifying whether the

  10. Reasoning about scene descriptions

    SciTech Connect

    DiManzo, M.; Adorni, G.; Giunchiglia, F.

    1986-07-01

    When a scene is described by means of natural language sentences, many details are usually omitted, because they are not in the focus of the conversation. Moreover, natural language is not the best tool to define precisely positions and spatial relationships. The process of interpreting ambiguous statements and inferring missing details involves many types of knowledge, from linguistics to physics. This paper is mainly concerned with the problem of modeling the process of understanding descriptions of static scenes. The specific topics covered by this work are the analysis of the meaning of spatial prepositions, the problem of the reference system and dimensionality, the activation of expectations about unmentioned objects, the role of default knowledge about object positions and its integration with contextual information sources, and the problem of space representation. The issue of understanding dynamic scenes descriptions is briefly approached in the last section.

  11. Spacelab J experiment descriptions

    SciTech Connect

    Miller, T.Y.

    1993-08-01

    Brief descriptions of the experiment investigations for the Spacelab J Mission which was launched from the Kennedy Space Center aboard the Endeavour in Sept. 1992 are presented. Experiments cover the following: semiconductor crystals; single crystals; superconducting composite materials; crystal growth; bubble behavior in weightlessness; microgravity environment; health monitoring of Payload Specialists; cultured plant cells; effect of low gravity on calcium metabolism and bone formation; and circadian rhythm. Separate abstracts have been prepared for articles from this report.

  12. Spacelab J experiment descriptions

    NASA Technical Reports Server (NTRS)

    Miller, Teresa Y. (Editor)

    1993-01-01

    Brief descriptions of the experiment investigations for the Spacelab J Mission which was launched from the Kennedy Space Center aboard the Endeavour in Sept. 1992 are presented. Experiments cover the following: semiconductor crystals; single crystals; superconducting composite materials; crystal growth; bubble behavior in weightlessness; microgravity environment; health monitoring of Payload Specialists; cultured plant cells; effect of low gravity on calcium metabolism and bone formation; and circadian rhythm.

  13. Probability density function formalism for optical coherence tomography signal analysis: a controlled phantom study.

    PubMed

    Weatherbee, Andrew; Sugita, Mitsuro; Bizheva, Kostadinka; Popov, Ivan; Vitkin, Alex

    2016-06-15

    The distribution of backscattered intensities as described by the probability density function (PDF) of tissue-scattered light contains information that may be useful for tissue assessment and diagnosis, including characterization of its pathology. In this Letter, we examine the PDF description of the light scattering statistics in a well characterized tissue-like particulate medium using optical coherence tomography (OCT). It is shown that for low scatterer density, the governing statistics depart considerably from a Gaussian description and follow the K distribution for both OCT amplitude and intensity. The PDF formalism is shown to be independent of the scatterer flow conditions; this is expected from theory, and suggests robustness and motion independence of the OCT amplitude (and OCT intensity) PDF metrics in the context of potential biomedical applications.

  14. A Fuzzy Description Logic with Automatic Object Membership Measurement

    NASA Astrophysics Data System (ADS)

    Cai, Yi; Leung, Ho-Fung

    In this paper, we propose a fuzzy description logic named f om -DL by combining the classical view in cognitive psychology and fuzzy set theory. A formal mechanism used to determine object memberships automatically in concepts is also proposed, which is lacked in previous work fuzzy description logics. In this mechanism, object membership is based on the defining properties of concept definition and properties in object description. Moreover, while previous works cannot express the qualitative measurements of an object possessing a property, we introduce two kinds of properties named N-property and L-property, which are quantitative measurements and qualitative measurements of an object possessing a property respectively. The subsumption and implication of concepts and properties are also explored in our work. We believe that it is useful to the Semantic Web community for reasoning the fuzzy membership of objects for concepts in fuzzy ontologies.

  15. The limits on combining recursive horn rules with description logics

    SciTech Connect

    Levy, A.Y.; Rousset, M.C.

    1996-12-31

    Horn rule languages have formed the basis for many Artificial Intelligence application languages, but are not expressive enough to model domains with a rich hierarchical structure. Description logics have been designed especially to model rich hierarchies. Several applications would significantly benefit from combining the expressive power of both formalisms. This paper focuses on combining recursive function-free Horn rules with the expressive description logic ALCNR, and shows exactly when a hybrid language with decidable inference can be obtained. First, we show that several of the core constructors of description logics lead by themselves to undecidability of inference when combined with recursive function-free Horn rules. We then show that without these constructors we obtain a maximal subset of ALCNRR that yields a decidable hybrid language. Finally, we describe a restriction on the Horn rules that guarantees decidable inference when combined with all of ALCNR, and covers many of the common usages of recursive rules.

  16. Mathematical Formalism for Designing Wide-Field X-Ray Telescopes: Mirror Nodal Positions and Detector Tilts

    NASA Technical Reports Server (NTRS)

    Elsner, R. F.; O'Dell, S. L.; Ramsey, B. D.; Weisskopf, M. C.

    2011-01-01

    We provide a mathematical formalism for optimizing the mirror nodal positions along the optical axis and the tilt of a commonly employed detector configuration at the focus of a x-ray telescope consisting of nested mirror shells with known mirror surface prescriptions. We adopt the spatial resolution averaged over the field-of-view as the figure of merit M. A more complete description appears in our paper in these proceedings.

  17. Formal verification of an oral messages algorithm for interactive consistency

    NASA Technical Reports Server (NTRS)

    Rushby, John

    1992-01-01

    The formal specification and verification of an algorithm for Interactive Consistency based on the Oral Messages algorithm for Byzantine Agreement is described. We compare our treatment with that of Bevier and Young, who presented a formal specification and verification for a very similar algorithm. Unlike Bevier and Young, who observed that 'the invariant maintained in the recursive subcases of the algorithm is significantly more complicated than is suggested by the published proof' and who found its formal verification 'a fairly difficult exercise in mechanical theorem proving,' our treatment is very close to the previously published analysis of the algorithm, and our formal specification and verification are straightforward. This example illustrates how delicate choices in the formulation of the problem can have significant impact on the readability of its formal specification and on the tractability of its formal verification.

  18. Microprocessor Simulation: A Training Technique.

    ERIC Educational Resources Information Center

    Oscarson, David J.

    1982-01-01

    Describes the design and application of a microprocessor simulation using BASIC for formal training of technicians and managers and as a management tool. Illustrates the utility of the modular approach for the instruction and practice of decision-making techniques. (SK)

  19. Interpretable Decision Sets: A Joint Framework for Description and Prediction

    PubMed Central

    Lakkaraju, Himabindu; Bach, Stephen H.; Jure, Leskovec

    2016-01-01

    One of the most important obstacles to deploying predictive models is the fact that humans do not understand and trust them. Knowing which variables are important in a model’s prediction and how they are combined can be very powerful in helping people understand and trust automatic decision making systems. Here we propose interpretable decision sets, a framework for building predictive models that are highly accurate, yet also highly interpretable. Decision sets are sets of independent if-then rules. Because each rule can be applied independently, decision sets are simple, concise, and easily interpretable. We formalize decision set learning through an objective function that simultaneously optimizes accuracy and interpretability of the rules. In particular, our approach learns short, accurate, and non-overlapping rules that cover the whole feature space and pay attention to small but important classes. Moreover, we prove that our objective is a non-monotone submodular function, which we efficiently optimize to find a near-optimal set of rules. Experiments show that interpretable decision sets are as accurate at classification as state-of-the-art machine learning techniques. They are also three times smaller on average than rule-based models learned by other methods. Finally, results of a user study show that people are able to answer multiple-choice questions about the decision boundaries of interpretable decision sets and write descriptions of classes based on them faster and more accurately than with other rule-based models that were designed for interpretability. Overall, our framework provides a new approach to interpretable machine learning that balances accuracy, interpretability, and computational efficiency. PMID:27853627

  20. Interpretable Decision Sets: A Joint Framework for Description and Prediction.

    PubMed

    Lakkaraju, Himabindu; Bach, Stephen H; Jure, Leskovec

    2016-08-01

    One of the most important obstacles to deploying predictive models is the fact that humans do not understand and trust them. Knowing which variables are important in a model's prediction and how they are combined can be very powerful in helping people understand and trust automatic decision making systems. Here we propose interpretable decision sets, a framework for building predictive models that are highly accurate, yet also highly interpretable. Decision sets are sets of independent if-then rules. Because each rule can be applied independently, decision sets are simple, concise, and easily interpretable. We formalize decision set learning through an objective function that simultaneously optimizes accuracy and interpretability of the rules. In particular, our approach learns short, accurate, and non-overlapping rules that cover the whole feature space and pay attention to small but important classes. Moreover, we prove that our objective is a non-monotone submodular function, which we efficiently optimize to find a near-optimal set of rules. Experiments show that interpretable decision sets are as accurate at classification as state-of-the-art machine learning techniques. They are also three times smaller on average than rule-based models learned by other methods. Finally, results of a user study show that people are able to answer multiple-choice questions about the decision boundaries of interpretable decision sets and write descriptions of classes based on them faster and more accurately than with other rule-based models that were designed for interpretability. Overall, our framework provides a new approach to interpretable machine learning that balances accuracy, interpretability, and computational efficiency.

  1. Connecting Formal and Informal Learning Experiences

    NASA Astrophysics Data System (ADS)

    O'Mahony, Timothy Kieran

    The learning study reports on part of a larger project being lead by the author. In this dissertation I explore one goal of this project---to understand effects on student learning outcomes as a function of using different methods for connecting out-of-school experiential learning with formal school-based instruction. There is a long history of assuming that "experience is the best teacher"(e.g. Aristotle, 360 BC; Dewey, 1934; Kolb, 1997; Pliny, AD 77). As a practical geographer I endorsed that assumption throughout my teaching career, paying attention to local topography, physical features, and natural resources in the geographic hinterland. I was particularly interested in understanding the impact of the physical landscape on humankind, and reciprocally, noting humankind's widespread impressions on the natural world. Until I began this research project, I assumed that everyone else paid a similar attention to immediate surroundings. The work that I describe in this dissertation emerges out of a conviction that there are many degrees of truth to the idea that experience is a great teacher. Its effectiveness seems to depend on how one's "experience" is mediated, and how "learning from it" is defined. This motivated me to think about design principles for linking people's experiences to learning. I began to explore, experimentally, how I might enhance people's abilities to notice, represent, and discuss their experiences in order to better learn from them. This study investigated how different ways of connecting outdoor learning experiences to formal schooling impacts students' performance. I studied high-school students in outdoor settings as they engaged in evocative issues of learning pertaining to consequential everyday life encounters. Different kinds of "expert mediation" were introduced and tested as the students engaged in investigative activities around the science of dam removal and habitat restoration. I measured outcomes with the aid of pre- and

  2. A formalism for the calculus of variations with spinors

    SciTech Connect

    Bäckdahl, Thomas; Valiente Kroon, Juan A.

    2016-02-15

    We develop a frame and dyad gauge-independent formalism for the calculus of variations of functionals involving spinorial objects. As a part of this formalism, we define a modified variation operator which absorbs frame and spin dyad gauge terms. This formalism is applicable to both the standard spacetime (i.e., SL(2, ℂ)) 2-spinors as well as to space (i.e., SU(2, ℂ)) 2-spinors. We compute expressions for the variations of the connection and the curvature spinors.

  3. Formal modeling and verification of fractional order linear systems.

    PubMed

    Zhao, Chunna; Shi, Likun; Guan, Yong; Li, Xiaojuan; Shi, Zhiping

    2016-05-01

    This paper presents a formalization of a fractional order linear system in a higher-order logic (HOL) theorem proving system. Based on the formalization of the Grünwald-Letnikov (GL) definition, we formally specify and verify the linear and superposition properties of fractional order systems. The proof provides a rigor and solid underpinnings for verifying concrete fractional order linear control systems. Our implementation in HOL demonstrates the effectiveness of our approach in practical applications.

  4. The Lagrangian-Hamiltonian formalism for higher order field theories

    NASA Astrophysics Data System (ADS)

    Vitagliano, Luca

    2010-06-01

    We generalize the Lagrangian-Hamiltonian formalism of Skinner and Rusk to higher order field theories on fiber bundles. As a byproduct we solve the long standing problem of defining, in a coordinate free manner, a Hamiltonian formalism for higher order Lagrangian field theories. Namely, our formalism does only depend on the action functional and, therefore, unlike previously proposed ones, is free from any relevant ambiguity.

  5. The formal verification used for the AAMP5 and AAMP-FV

    NASA Technical Reports Server (NTRS)

    Srivas, Mandayam

    1995-01-01

    The main goal of the project was two-fold: First, to investigate the feasibility of formally specifying and verifying a complex commercial microprocessor that was not expressly designed for formal verification. Second, to explore effective ways to transfer the technology to an industrial setting. The choice of the AAMP5 satisfied the first goal since the AAMP5 was not designed for formal verification, but to provide a more than threefold performance improvement while remaining object-code-compatible with the earlier AAMP2, which is used in numerous avionics applications, including the Boeing 737, 747, 757, and 767. To satisfy the technology transfer objective, we had to develop a suitable verification methodology and a formal infrastructure to make the technology usable by practicing engineers. This infrastructure includes techniques for decomposing the microcompressor verification problem into a st of verification conditions that the engineers can formulate and strategies to automate the proof of the verification conditions. The development of the infrastructure was one of the key accomplishments of the project. Most of the infrastructure and methodology are general enough to be reused for other microprocessors, certainly in the verification of another member of the AAMP family. This methodology was used to formally specify the entire microarchitecture and more than half of the instruction set and to verify a core set of eleven AAMP5 instructions representative of several instruction classes. However, the methodology and the formal machinery developed are adequate to cover most of the remaining AAMP5 instructions. Although PVS was the vehicle of the experiment, the methodology is applicable to other sufficiently powerful theorem provers.

  6. A Formal Semantics for the SRI Hierarchical Program Design Methodology

    NASA Technical Reports Server (NTRS)

    Boyer, R. S.; Moore, J. S.

    1983-01-01

    A formal statement of what it means to use (a subset of) the methodology is presented. It is formally defined that some specified module exists and what it means to say that another module is paid correctly implemented on top of it. No attention is to motivation, either of the methodology or of the formal development of it. Concentration is entirely upon mathematical succinctness and precision. A discussion is presented of how to use certain INTERLISP programs which implement the formal definitions. Among these are a program which generates Floyd like verification conditions sufficient to imply the correctness of a module implementation.

  7. Functional Lagrange formalism for time-non-local Lagrangians

    NASA Astrophysics Data System (ADS)

    Ferialdi, L.; Bassi, A.

    2012-05-01

    We develop a time-non-local (TNL) formalism based on variational calculus, which allows for the analysis of TNL Lagrangians. We derive the generalized Euler-Lagrange equations starting from the Hamilton's principle and, by defining a generalized momentum, we introduce the corresponding Hamiltonian formalism. We apply the formalism to second order TNL Lagrangians and we show that it reproduces standard results in the time-local limit. An example will show how the formalism works, and will provide an interesting insight on the non-standard features of TNL equations.

  8. Historical revision of the differential Stokes-Mueller formalism: discussion.

    PubMed

    Arteaga, Oriol

    2017-03-01

    The differential Stokes-Mueller matrix formalism expresses the local evolution of the Mueller matrix or the Stokes parameters for light propagating through a homogeneous optical medium. This paper presents a historical revision of the development of the differential Stokes-Mueller matrix formalism and highlights several important early contributions that have been overlooked. Particularly relevant is that this formalism was pioneered as early as 1929 by Paul Soleillet, almost 50 years earlier than it has been usually assumed. This historical revision demonstrates that several different authors independently formulated the differential Stokes-Mueller formalism during the 20th century and they found equivalent results studying the propagation problem from different approaches.

  9. On Applicability of Formal Methods and Tools to Dependable Services

    NASA Astrophysics Data System (ADS)

    Ishikawa, Fuyuki; Honiden, Shinichi

    As a variety of digital services are provided through networks, more and more efforts are made to ensure dependability of software behavior implementing services. Formal methods and tools have been considered as promising means to support dependability in complex software systems during the development. On the other hand, there have been serious doubts on practical applicability of formal methods. This paper overviews the present state of formal methods and discusses their applicability, especially focusing on two representative methods (SPIN and B Method) and their recent industrial applications. This paper also discusses applications of formal methods to dependable networked software.

  10. Toward solotronics design in the Wigner formalism

    NASA Astrophysics Data System (ADS)

    Sellier, J. M.; Dimov, I.

    2015-01-01

    The capability of manipulating single dopant atoms in semiconductor materials, with atomic precision, has given birth to a new branch of electronics known as solotronics (solitary dopant optoelectronics). While experiments are advancing rapidly, the theoretical comprehension of quantum phenomena occurring at that scale is relatively basic. Indeed, in this context, simulations come with incredible mathematical challenges. This eventually prevents practical design and optimization of solotronic devices. In this work, we focus our attention on a planar honeycomb structure exploiting single dopants embedded in silicon and study under which conditions it behaves as an electron ballistic channel. To this aim, we apply the time-dependent Wigner Monte Carlo formalism, based on signed particles to simulate and analyze the phenomena occurring in the proposed structure. We show that, by positioning the dopant atoms (phosphorus and boron) in particular planar patterns (honeycomb), it is possible to control the dynamics of a single electron. Finally, by introducing spatial distortions, we can show how the time-dependent electron dynamics is eventually affected. The results confirm that the Wigner Monte Carlo method is an efficient TCAD (Technology Computer Aided Design) tool which can be exploited for the time-dependent simulation of even more realistic situations necessary for the design of active solotronic devices.

  11. Boltzmann hierarchy for interacting neutrinos I: formalism

    SciTech Connect

    Oldengott, Isabel M.; Rampf, Cornelius; Wong, Yvonne Y.Y. E-mail: cornelius.rampf@port.ac.uk

    2015-04-01

    Starting from the collisional Boltzmann equation, we derive for the first time and from first principles the Boltzmann hierarchy for neutrinos including interactions with a scalar particle. Such interactions appear, for example, in majoron-like models of neutrino mass generation. We study two limits of the scalar mass: (i) An extremely massive scalar whose only role is to mediate an effective 4-fermion neutrino-neutrino interaction, and (ii) a massless scalar that can be produced in abundance and thus demands its own Boltzmann hierarchy. In contrast to, e.g., the first-order Boltzmann hierarchy for Thomson-scattering photons, our interacting neutrino/scalar Boltzmann hierarchies contain additional momentum-dependent collision terms arising from a non-negligible energy transfer in the neutrino-neutrino and neutrino-scalar interactions. This necessitates that we track each momentum mode of the phase space distributions individually, even if the particles were massless. Comparing our hierarchy with the commonly used (c{sub eff}{sup 2},c{sub vis}{sup 2})-parameterisation, we find no formal correspondence between the two approaches, which raises the question of whether the latter parameterisation even has an interpretation in terms of particle scattering. Lastly, although we have invoked majoron-like models as a motivation for our study, our treatment is in fact generally applicable to all scenarios in which the neutrino and/or other ultrarelativistic fermions interact with scalar particles.

  12. Formal groups and Z-entropies

    NASA Astrophysics Data System (ADS)

    Tempesta, Piergiulio

    2016-11-01

    We shall prove that the celebrated Rényi entropy is the first example of a new family of infinitely many multi-parametric entropies. We shall call them the Z-entropies. Each of them, under suitable hypotheses, generalizes the celebrated entropies of Boltzmann and Rényi. A crucial aspect is that every Z-entropy is composable (Tempesta 2016 Ann. Phys. 365, 180-197. (doi:10.1016/j.aop.2015.08.013)). This property means that the entropy of a system which is composed of two or more independent systems depends, in all the associated probability space, on the choice of the two systems only. Further properties are also required to describe the composition process in terms of a group law. The composability axiom, introduced as a generalization of the fourth Shannon-Khinchin axiom (postulating additivity), is a highly non-trivial requirement. Indeed, in the trace-form class, the Boltzmann entropy and Tsallis entropy are the only known composable cases. However, in the non-trace form class, the Z-entropies arise as new entropic functions possessing the mathematical properties necessary for information-theoretical applications, in both classical and quantum contexts. From a mathematical point of view, composability is intimately related to formal group theory of algebraic topology. The underlying group-theoretical structure determines crucially the statistical properties of the corresponding entropies.

  13. Formal Methods Applications in Air Transportation

    NASA Technical Reports Server (NTRS)

    Farley, Todd

    2009-01-01

    The U.S. air transportation system is the most productive in the world, moving far more people and goods than any other. It is also the safest system in the world, thanks in part to its venerable air traffic control system. But as demand for air travel continues to grow, the air traffic control system s aging infrastructure and labor-intensive procedures are impinging on its ability to keep pace with demand. And that impinges on the growth of our economy. Air traffic control modernization has long held the promise of a more efficient air transportation system. Part of NASA s current mission is to develop advanced automation and operational concepts that will expand the capacity of our national airspace system while still maintaining its excellent record for safety. It is a challenging mission, as efforts to modernize have, for decades, been hamstrung by the inability to assure safety to the satisfaction of system operators, system regulators, and/or the traveling public. In this talk, we ll provide a brief history of air traffic control, focusing on the tension between efficiency and safety assurance, and the promise of formal methods going forward.

  14. The Parametrized Post-Newtonian-Vainshteinian formalism

    SciTech Connect

    Avilez-Lopez, A.; Padilla, A.; Saffin, Paul M.; Skordis, C. E-mail: antonio.padilla@nottingham.ac.uk E-mail: skordis@ucy.ac.cy

    2015-06-01

    Light degrees of freedom that modify gravity on cosmological scales must be ''screened' on solar system scales in order to be compatible with data. The Vainshtein mechanism achieves this through a breakdown of classical perturbation theory, as large interactions involving new degrees of freedom become important below the so-called Vainshtein radius. We begin to develop an extension of the Parameterized Post-Newtonian (PPN) formalism that is able to handle Vainshteinian corrections. We argue that theories with a unique Vainshtein scale must be expanded using two small parameters. In this Parameterized Post-Newtonian-Vainshteinian (PPNV) expansion, the primary expansion parameter that controls the PPN order is, as usual, the velocity v. The secondary expansion parameter, α, controls the strength of the Vainshteinian correction and is a theory-specific combination of the Schwarzschild radius and the Vainshtein radius of the source that is independent of its mass. We present the general framework and apply it to Cubic Galileon theory both inside and outside the Vainshtein radius. The PPNV framework can be used to determine the compatibility of such theories with solar system and other strong-field data.

  15. Fostering Formal Commutativity Knowledge with Approximate Arithmetic

    PubMed Central

    Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A.; Gaschler, Robert

    2015-01-01

    How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311

  16. Formal groups and Z-entropies.

    PubMed

    Tempesta, Piergiulio

    2016-11-01

    We shall prove that the celebrated Rényi entropy is the first example of a new family of infinitely many multi-parametric entropies. We shall call them the Z-entropies. Each of them, under suitable hypotheses, generalizes the celebrated entropies of Boltzmann and Rényi. A crucial aspect is that every Z-entropy is composable (Tempesta 2016 Ann. Phys.365, 180-197. (doi:10.1016/j.aop.2015.08.013)). This property means that the entropy of a system which is composed of two or more independent systems depends, in all the associated probability space, on the choice of the two systems only. Further properties are also required to describe the composition process in terms of a group law. The composability axiom, introduced as a generalization of the fourth Shannon-Khinchin axiom (postulating additivity), is a highly non-trivial requirement. Indeed, in the trace-form class, the Boltzmann entropy and Tsallis entropy are the only known composable cases. However, in the non-trace form class, the Z-entropies arise as new entropic functions possessing the mathematical properties necessary for information-theoretical applications, in both classical and quantum contexts. From a mathematical point of view, composability is intimately related to formal group theory of algebraic topology. The underlying group-theoretical structure determines crucially the statistical properties of the corresponding entropies.

  17. Whatever Happened to Formal Methods for Security?

    PubMed Central

    Voas, J.; Schaffer, K.

    2016-01-01

    We asked 7 experts 7 questions to find out what has occurred recently in terms of applying formal methods (FM) to security-centric, cyber problems. We are continually reminded of the 1996 paper by Tony Hoare “How did Software Get So Reliable Without Proof?” [1] In that vein, how did we get so insecure with proof? Given daily press announcements concerning new malware, data breaches, and privacy loss, is FM still relevant or was it ever? Our experts answered with unique personal insights. We were curious as to whether this successful methodology in “safety-critical” has succeeded as well for today’s “build it, hack it, patch it” mindset. Our experts were John McLean (Naval Research Labs), Paul Black (National Institute of Standards and Technology), Karl Levitt (University of California at Davis), Joseph Williams (CloudEconomist.Com), Connie Heitmeyer (Naval Research Labs), Eugene Spafford (Purdue University), and Joseph Kiniry (Galois, Inc.). The questions and responses follow. PMID:27890940

  18. Interpreter composition issues in the formal verification of a processor-memory module

    NASA Technical Reports Server (NTRS)

    Fura, David A.; Cohen, Gerald C.

    1994-01-01

    This report describes interpreter composition techniques suitable for the formal specification and verification of a processor-memory module using the HOL theorem proving system. The processor-memory module is a multichip subsystem within a fault-tolerant embedded system under development within the Boeing Defense and Space Group. Modeling and verification methods were developed that permit provably secure composition at the transaction-level of specification, significantly reducing the complexity of the hierarchical verification of the system.

  19. Using Ontologies to Formalize Services Specifications in Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Breitman, Karin Koogan; Filho, Aluizio Haendchen; Haeusler, Edward Hermann

    2004-01-01

    One key issue in multi-agent systems (MAS) is their ability to interact and exchange information autonomously across applications. To secure agent interoperability, designers must rely on a communication protocol that allows software agents to exchange meaningful information. In this paper we propose using ontologies as such communication protocol. Ontologies capture the semantics of the operations and services provided by agents, allowing interoperability and information exchange in a MAS. Ontologies are a formal, machine processable, representation that allows to capture the semantics of a domain and, to derive meaningful information by way of logical inference. In our proposal we use a formal knowledge representation language (OWL) that translates into Description Logics (a subset of first order logic), thus eliminating ambiguities and providing a solid base for machine based inference. The main contribution of this approach is to make the requirements explicit, centralize the specification in a single document (the ontology itself), at the same that it provides a formal, unambiguous representation that can be processed by automated inference machines.

  20. The Genre of Technical Description.

    ERIC Educational Resources Information Center

    Jordan, Michael P.

    1986-01-01

    Summarizes recent research into systems of lexical and grammatical cohesion in technical description. Discusses various methods by which technical writers "re-enter" the topic of description back into the text in successive sentences. (HTH)

  1. Formalizing structured file services for the data storage and retrieval subsystem of the data management system for Spacestation Freedom

    NASA Technical Reports Server (NTRS)

    Jamsek, Damir A.

    1993-01-01

    A brief example of the use of formal methods techniques in the specification of a software system is presented. The report is part of a larger effort targeted at defining a formal methods pilot project for NASA. One possible application domain that may be used to demonstrate the effective use of formal methods techniques within the NASA environment is presented. It is not intended to provide a tutorial on either formal methods techniques or the application being addressed. It should, however, provide an indication that the application being considered is suitable for a formal methods by showing how such a task may be started. The particular system being addressed is the Structured File Services (SFS), which is a part of the Data Storage and Retrieval Subsystem (DSAR), which in turn is part of the Data Management System (DMS) onboard Spacestation Freedom. This is a software system that is currently under development for NASA. An informal mathematical development is presented. Section 3 contains the same development using Penelope (23), an Ada specification and verification system. The complete text of the English version Software Requirements Specification (SRS) is reproduced in Appendix A.

  2. MCO Monitoring activity description

    SciTech Connect

    SEXTON, R.A.

    1998-11-09

    Spent Nuclear Fuel remaining from Hanford's N-Reactor operations in the 1970s has been stored under water in the K-Reactor Basins. This fuel will be repackaged, dried and stored in a new facility in the 200E Area. The safety basis for this process of retrieval, drying, and interim storage of the spent fuel has been established. The monitoring of MCOS in dry storage is a currently identified issue in the SNF Project. This plan outlines the key elements of the proposed monitoring activity. Other fuel stored in the K-Reactor Basins, including SPR fuel, will have other monitoring considerations and is not addressed by this activity description.

  3. Diabatic Population Matrix Formalism for Performing Molecular Mechanics Style Simulations with Multiple Electronic States.

    PubMed

    Park, Jae Woo; Rhee, Young Min

    2014-12-09

    An accurate description of nonbonded interactions is important in investigating dynamics of molecular systems. In many situations, fixed point charge models are successfully applied to explaining various chemical phenomena. However, these models with conventional formulations will not be appropriate in elucidating the detailed dynamics during nonadiabatic events. This is mainly because the chemical properties of any molecule, especially its electronic populations, significantly change with respect to molecular distortions in the vicinity of the surface crossing. To overcome this issue in molecular simulations yet within the framework of the fixed point charge model, we define a diabatic electronic population matrix and substitute it for the conventional adiabatic partial charges. We show that this matrix can be readily utilized toward attaining more reliable descriptions of Coulombic interactions, in combination with the interpolation formalism for obtaining the intramolecular interaction potential. We demonstrate how the mixed formalism with the diabatic charges and the interpolation can be applied to molecular simulations by conducting adiabatic and nonadiabatic molecular dynamics trajectory calculations of the green fluorescent protein chromophore anion in aqueous environment.

  4. Three Approaches to Descriptive Research.

    ERIC Educational Resources Information Center

    Svensson, Lennart

    This report compares three approaches to descriptive research, focusing on the kinds of descriptions developed and on the methods used to develop the descriptions. The main emphasis in all three approaches is on verbal data. In these approaches the importance of interpretation and its intuitive nature are emphasized. The three approaches, however,…

  5. Formal education and back pain: a review

    PubMed Central

    Dionne, C; Von Korff, M; Koepsell, T; Deyo, R; Barlow, W; Checkoway, H

    2001-01-01

    OBJECTIVES—To summarise the scientific evidence on the relation between educational status and measures of the frequency and the consequences of back pain and of the outcomes of interventions among back pain patients, and to outline possible mechanisms that could explain such an association if found.
DESIGN—Sixty four articles published between 1966 and 2000 that documented the association of formal education with back pain were reviewed.
MAIN RESULTS—Overall, the current available evidence points indirectly to a stronger association of low education with longer duration and/or higher recurrence of back pain than to an association with onset. The many reports of an association of low education with adverse consequences of back pain also suggest that the course of a back pain episode is less favourable among persons with low educational attainment. Mechanisms that could explain these associations include variations in behavioural and environmental risk factors by educational status, differences in occupational factors, compromised "health stock" among people with low education, differences in access to and utilisation of health services, and adaptation to stress. Although lower education was not associated with the outcomes of interventions in major studies, it is difficult, in light of the current limited available evidence, to draw firm conclusions on this association.
CONCLUSION—Scientific evidence supports the hypothesis that less well educated people are more likely to be affected by disabling back pain. Further study of this association may help advance our understanding of back pain as well as understanding of the relation between socioeconomic status and disease as a general phenomenon.


Keywords: back pain; educational status PMID:11413174

  6. A formal model of interpersonal inference

    PubMed Central

    Moutoussis, Michael; Trujillo-Barreto, Nelson J.; El-Deredy, Wael; Dolan, Raymond J.; Friston, Karl J.

    2014-01-01

    Introduction: We propose that active Bayesian inference—a general framework for decision-making—can equally be applied to interpersonal exchanges. Social cognition, however, entails special challenges. We address these challenges through a novel formulation of a formal model and demonstrate its psychological significance. Method: We review relevant literature, especially with regards to interpersonal representations, formulate a mathematical model and present a simulation study. The model accommodates normative models from utility theory and places them within the broader setting of Bayesian inference. Crucially, we endow people's prior beliefs, into which utilities are absorbed, with preferences of self and others. The simulation illustrates the model's dynamics and furnishes elementary predictions of the theory. Results: (1) Because beliefs about self and others inform both the desirability and plausibility of outcomes, in this framework interpersonal representations become beliefs that have to be actively inferred. This inference, akin to “mentalizing” in the psychological literature, is based upon the outcomes of interpersonal exchanges. (2) We show how some well-known social-psychological phenomena (e.g., self-serving biases) can be explained in terms of active interpersonal inference. (3) Mentalizing naturally entails Bayesian updating of how people value social outcomes. Crucially this includes inference about one's own qualities and preferences. Conclusion: We inaugurate a Bayes optimal framework for modeling intersubject variability in mentalizing during interpersonal exchanges. Here, interpersonal representations are endowed with explicit functional and affective properties. We suggest the active inference framework lends itself to the study of psychiatric conditions where mentalizing is distorted. PMID:24723872

  7. On the simulation of indistinguishable fermions in the many-body Wigner formalism

    NASA Astrophysics Data System (ADS)

    Sellier, J. M.; Dimov, I.

    2015-01-01

    The simulation of quantum systems consisting of interacting, indistinguishable fermions is an incredible mathematical problem which poses formidable numerical challenges. Many sophisticated methods addressing this problem are available which are based on the many-body Schrödinger formalism. Recently a Monte Carlo technique for the resolution of the many-body Wigner equation has been introduced and successfully applied to the simulation of distinguishable, spinless particles. This numerical approach presents several advantages over other methods. Indeed, it is based on an intuitive formalism in which quantum systems are described in terms of a quasi-distribution function, and highly scalable due to its Monte Carlo nature. In this work, we extend the many-body Wigner Monte Carlo method to the simulation of indistinguishable fermions. To this end, we first show how fermions are incorporated into the Wigner formalism. Then we demonstrate that the Pauli exclusion principle is intrinsic to the formalism. As a matter of fact, a numerical simulation of two strongly interacting fermions (electrons) is performed which clearly shows the appearance of a Fermi (or exchange-correlation) hole in the phase-space, a clear signature of the presence of the Pauli principle. To conclude, we simulate 4, 8 and 16 non-interacting fermions, isolated in a closed box, and show that, as the number of fermions increases, we gradually recover the Fermi-Dirac statistics, a clear proof of the reliability of our proposed method for the treatment of indistinguishable particles.

  8. Potentiometric determination of the 'formal' hydrolysis ratio of aluminium species in aqueous solutions.

    PubMed

    Fournier, Agathe C; Shafran, Kirill L; Perry, Carole C

    2008-01-21

    The 'formal' hydrolysis ratio (h = C(OH-)added/C(Al)total) of hydrolysed aluminium-ions is an important parameter required for the exhaustive and quantitative speciation-fractionation of aluminium in aqueous solutions. This paper describes a potentiometric method for determination of the formal hydrolysis ratio based on an automated alkaline titration procedure. The method uses the point of precipitation of aluminium hydroxide as a reference (h = 3.0) in order to calculate the initial formal hydrolysis ratio of hydrolysed aluminium-ion solutions. Several solutions of pure hydrolytic species including aluminium monomers (AlCl3), Al13 polynuclear cluster ([Al13O4(OH)24(H2O)12]7+), Al30 polynuclear cluster ([Al30O8(OH)56(H2O)26]18+) and a suspension of nanoparticulate aluminium hydroxide have been used as 'reference standards' to validate the proposed potentiometric method. Other important variables in the potentiometric determination of the hydrolysis ratio have also been optimised including the concentration of aluminium and the type and strength of alkali (Trizma-base, NH3, NaHCO3, Na2CO3 and KOH). The results of the potentiometric analysis have been cross-verified by quantitative 27Al solution nuclear magnetic resonance (27Al NMR) measurements. The 'formal' hydrolysis ratio of a commercial basic aluminium chloride has been measured as an example of a practical application of the developed technique.

  9. Annotation of rule-based models with formal semantics to enable creation, analysis, reuse and visualization

    PubMed Central

    Misirli, Goksel; Cavaliere, Matteo; Waites, William; Pocock, Matthew; Madsen, Curtis; Gilfellon, Owen; Honorato-Zimmer, Ricardo; Zuliani, Paolo; Danos, Vincent; Wipat, Anil

    2016-01-01

    Motivation: Biological systems are complex and challenging to model and therefore model reuse is highly desirable. To promote model reuse, models should include both information about the specifics of simulations and the underlying biology in the form of metadata. The availability of computationally tractable metadata is especially important for the effective automated interpretation and processing of models. Metadata are typically represented as machine-readable annotations which enhance programmatic access to information about models. Rule-based languages have emerged as a modelling framework to represent the complexity of biological systems. Annotation approaches have been widely used for reaction-based formalisms such as SBML. However, rule-based languages still lack a rich annotation framework to add semantic information, such as machine-readable descriptions, to the components of a model. Results: We present an annotation framework and guidelines for annotating rule-based models, encoded in the commonly used Kappa and BioNetGen languages. We adapt widely adopted annotation approaches to rule-based models. We initially propose a syntax to store machine-readable annotations and describe a mapping between rule-based modelling entities, such as agents and rules, and their annotations. We then describe an ontology to both annotate these models and capture the information contained therein, and demonstrate annotating these models using examples. Finally, we present a proof of concept tool for extracting annotations from a model that can be queried and analyzed in a uniform way. The uniform representation of the annotations can be used to facilitate the creation, analysis, reuse and visualization of rule-based models. Although examples are given, using specific implementations the proposed techniques can be applied to rule-based models in general. Availability and implementation: The annotation ontology for rule-based models can be found at http

  10. On a purported local extension of the quantum formalism

    NASA Astrophysics Data System (ADS)

    Melia, Joseph; Redhead, Michael

    1999-09-01

    It is widely believed that Bell has proved there can be no consistent local extension of the quantum formalism. Against this, Angelidis has presented a hidden variable theory which, he claims, makes precisely the same predictions as the quantum formalism and which also satisfies locality. In this note, we argue that Angelidis' theory does not live up to its inventor's claims.

  11. How Online Journalists Learn within a Non-Formal Context

    ERIC Educational Resources Information Center

    Kronstad, Morten; Eide, Martin

    2015-01-01

    Purpose: The purpose of this paper is to contribute to the understanding of workplace learning, with a focus on the non-formal learning that takes place among online journalists. The focus of this article is journalists working in an online newspaper and their experiences with workplace and non-formal learning, centering on framework conditions…

  12. Adolescent Egocentrism and Formal Operations: Tests of a Theoretical Assumption.

    ERIC Educational Resources Information Center

    Lapsley, David K.; And Others

    1986-01-01

    Describes two studies of the theoretical relation between adolescent egocentrism and formal operations. Study 1 used the Adolescent Egocentrism Scale (AES) and Lunzer's battery of formal reasoning tasks to assess 183 adolescents. Study 2 administered the AES, the Imaginary Audience Scale (IAS), and the Test of Logical Thinking to 138 adolescents.…

  13. Formal or Nonformal Education? Entrepreneurial Women in Ghana.

    ERIC Educational Resources Information Center

    Robertson, Claire C.

    1984-01-01

    Ghanian women have a long history as traders. In early 1978, 42 Central Accra schoolgirls and 42 girls engaged in selling were surveyed to determine the relationship of formal education to marketing skills. Formal education was not significantly helpful in promoting schoolgirls' trading knowledge nor in providing skills likely to land them jobs.…

  14. Does the nontrivially deformed field-antifield formalism exist?

    NASA Astrophysics Data System (ADS)

    Batalin, Igor A.; Lavrov, Peter M.

    2015-06-01

    We reformulate the Lagrange deformed field-antifield BV-formalism suggested, in terms of the general Euler vector field N generated by the antisymplectic potential. That N generalizes, in a natural anticanonically-invariant manner, the usual power-counting operator. We provide for the "usual" gauge-fixing mechanism as applied to the deformed BV-formalism.

  15. 47 CFR 6.16 - Informal or formal complaints.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Informal or formal complaints. 6.16 Section 6..., TELECOMMUNICATIONS EQUIPMENT AND CUSTOMER PREMISES EQUIPMENT BY PERSONS WITH DISABILITIES Enforcement § 6.16 Informal or formal complaints. Complaints against manufacturers or providers, as defined under this...

  16. 47 CFR 8.14 - General formal complaint procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...

  17. 47 CFR 8.14 - General formal complaint procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...

  18. 47 CFR 8.14 - General formal complaint procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...

  19. 47 CFR 8.14 - General formal complaint procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false General formal complaint procedures. 8.14 Section 8.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRESERVING THE OPEN INTERNET § 8.14 General formal complaint procedures. (a) Complaints. In addition to the general...

  20. Blending Formal and Informal Learning Networks for Online Learning

    ERIC Educational Resources Information Center

    Czerkawski, Betül C.

    2016-01-01

    With the emergence of social software and the advance of web-based technologies, online learning networks provide invaluable opportunities for learning, whether formal or informal. Unlike top-down, instructor-centered, and carefully planned formal learning settings, informal learning networks offer more bottom-up, student-centered participatory…

  1. On the Equivalence of Formal Grammars and Machines.

    ERIC Educational Resources Information Center

    Lund, Bruce

    1991-01-01

    Explores concepts of formal language and automata theory underlying computational linguistics. A computational formalism is described known as a "logic grammar," with which computational systems process linguistic data, with examples in declarative and procedural semantics and definite clause grammars. (13 references) (CB)

  2. Beyond Formalism: Literary Criticism Now and in the Immediate Future.

    ERIC Educational Resources Information Center

    Standley, Fred L.

    Formalism, an amalgamation of literary critical methods originating in the 1920's, which emphasize close textual analysis of the literary work itself, is declining as the predominant critical approach due to its self-imposed limitations. New perspectives, attempting to counter the fragmentation of formalism and demonstrating an awareness of the…

  3. Automatically Grading Customer Confidence in a Formal Specification.

    ERIC Educational Resources Information Center

    Shukur, Zarina; Burke, Edmund; Foxley, Eric

    1999-01-01

    Describes an automatic grading system for a formal methods computer science course that is able to evaluate a formal specification written in the Z language. Quality is measured by considering first, specification correctness (syntax, semantics, and satisfaction of customer requirements), and second, specification maintainability (comparison of…

  4. 49 CFR 209.8 - Depositions in formal proceedings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Depositions in formal proceedings. 209.8 Section... in formal proceedings. (a) Any party to a proceeding under subpart B, C, or D of this part may take... witnesses may be compelled by subpoena as provided in § 209.7 and, for proceedings under subpart D of...

  5. The Role of Formal Rules in Pronunciation Instruction.

    ERIC Educational Resources Information Center

    Dickerson, Wayne B.

    Both aural-oral practice with the sounds of English and formal rules are important in pronunciation instruction, and have a role to play in interlanguage development. Formal rules provide self-evaluation for purposes of self-correction, a process which allows learners to judge or self-correct their own utterances against rule-generated predictions…

  6. Enhancing Formal E-Learning with Edutainment on Social Networks

    ERIC Educational Resources Information Center

    Labus, A.; Despotovic-Zrakic, M.; Radenkovic, B.; Bogdanovic, Z.; Radenkovic, M.

    2015-01-01

    This paper reports on the investigation of the possibilities of enhancing the formal e-learning process by harnessing the potential of informal game-based learning on social networks. The goal of the research is to improve the outcomes of the formal learning process through the design and implementation of an educational game on a social network…

  7. Academic Achievement and Formal Thought in Engineering Students

    ERIC Educational Resources Information Center

    Vazquez, Stella Maris; de Anglat, Hilda Difabio

    2009-01-01

    Introduction: Research on university-level academic performance has significantly linked failure and dropping out to formal reasoning deficiency. We have not found any papers on formal thought in Argentine university students, in spite of the obvious shortcomings observed in the classrooms. Thus, the main objective of this paper was exploring the…

  8. I, Pronoun: A Study of Formality in Online Content

    ERIC Educational Resources Information Center

    Thayer, Alexander; Evans, Mary B.; McBride, Alicia A.; Queen, Matt; Spyridakis, Jan H.

    2010-01-01

    This article presents the results of a study that investigated readers' perceptions of tone formality in online text passages. The study found that readers perceived text passages to be less formal when they contained personal pronouns, active voice verbs, informal punctuation, or verb contractions. The study reveals that professional…

  9. Integrating Formal and Grounded Representations in Combinatorics Learning

    ERIC Educational Resources Information Center

    Braithwaite, David W.; Goldstone, Robert L.

    2013-01-01

    The terms "concreteness fading" and "progressive formalization" have been used to describe instructional approaches to science and mathematics that use grounded representations to introduce concepts and later transition to more formal representations of the same concepts. There are both theoretical and empirical reasons to…

  10. Home Education Transitions with Formal Schooling: Student Perspectives

    ERIC Educational Resources Information Center

    Jackson, Glenda

    2007-01-01

    Home education is a well established phenomenon in Australia but little is known about the movement of students between home schooling and formal education and how students view and handle the transitions. A sociocultural theoretical framework has been used to explore student perceptions of their transition experiences between formal education and…

  11. Toward the Characterization of Non-Formal Pedagogy.

    ERIC Educational Resources Information Center

    Silberman-Keller, Diana

    This study examined characteristic attributes of non-formal education and the non-formal pedagogy directing its teaching and learning processes. Data were collected on organizational and pedagogical characteristics in several out-of-school organizations (youth movements, youth organizations, community centers, bypass educational systems, local…

  12. Toward a mathematical formalism of performance, task difficulty, and activation

    NASA Technical Reports Server (NTRS)

    Samaras, George M.

    1988-01-01

    The rudiments of a mathematical formalism for handling operational, physiological, and psychological concepts are developed for use by the man-machine system design engineer. The formalism provides a framework for developing a structured, systematic approach to the interface design problem, using existing mathematical tools, and simplifying the problem of telling a machine how to measure and use performance.

  13. 7 CFR 1487.7 - How are agreements formalized?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false How are agreements formalized? 1487.7 Section 1487.7 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT....7 How are agreements formalized? Following the approval of a proposal, the CCC will enter into...

  14. Quantum optimal control theory in the linear response formalism

    SciTech Connect

    Castro, Alberto; Tokatly, I. V.

    2011-09-15

    Quantum optimal control theory (QOCT) aims at finding an external field that drives a quantum system in such a way that optimally achieves some predefined target. In practice, this normally means optimizing the value of some observable, a so-called merit function. In consequence, a key part of the theory is a set of equations, which provides the gradient of the merit function with respect to parameters that control the shape of the driving field. We show that these equations can be straightforwardly derived using the standard linear response theory, only requiring a minor generalization: the unperturbed Hamiltonian is allowed to be time dependent. As a result, the aforementioned gradients are identified with certain response functions. This identification leads to a natural reformulation of QOCT in terms of the Keldysh contour formalism of the quantum many-body theory. In particular, the gradients of the merit function can be calculated using the diagrammatic technique for nonequilibrium Green's functions, which should be helpful in the application of QOCT to computationally difficult many-electron problems.

  15. Formal Verification of a Conflict Resolution and Recovery Algorithm

    NASA Technical Reports Server (NTRS)

    Maddalon, Jeffrey; Butler, Ricky; Geser, Alfons; Munoz, Cesar

    2004-01-01

    New air traffic management concepts distribute the duty of traffic separation among system participants. As a consequence, these concepts have a greater dependency and rely heavily on on-board software and hardware systems. One example of a new on-board capability in a distributed air traffic management system is air traffic conflict detection and resolution (CD&R). Traditional methods for safety assessment such as human-in-the-loop simulations, testing, and flight experiments may not be sufficient for this highly distributed system as the set of possible scenarios is too large to have a reasonable coverage. This paper proposes a new method for the safety assessment of avionics systems that makes use of formal methods to drive the development of critical systems. As a case study of this approach, the mechanical veri.cation of an algorithm for air traffic conflict resolution and recovery called RR3D is presented. The RR3D algorithm uses a geometric optimization technique to provide a choice of resolution and recovery maneuvers. If the aircraft adheres to these maneuvers, they will bring the aircraft out of conflict and the aircraft will follow a conflict-free path to its original destination. Veri.cation of RR3D is carried out using the Prototype Verification System (PVS).

  16. Core Benchmarks Descriptions

    SciTech Connect

    Pavlovichev, A.M.

    2001-05-24

    Actual regulations while designing of new fuel cycles for nuclear power installations comprise a calculational justification to be performed by certified computer codes. It guarantees that obtained calculational results will be within the limits of declared uncertainties that are indicated in a certificate issued by Gosatomnadzor of Russian Federation (GAN) and concerning a corresponding computer code. A formal justification of declared uncertainties is the comparison of calculational results obtained by a commercial code with the results of experiments or of calculational tests that are calculated with an uncertainty defined by certified precision codes of MCU type or of other one. The actual level of international cooperation provides an enlarging of the bank of experimental and calculational benchmarks acceptable for a certification of commercial codes that are being used for a design of fuel loadings with MOX fuel. In particular, the work is practically finished on the forming of calculational benchmarks list for a certification of code TVS-M as applied to MOX fuel assembly calculations. The results on these activities are presented.

  17. Developing Musicality: Formal and Informal Practices

    ERIC Educational Resources Information Center

    Jaffurs, Sheri E.

    2004-01-01

    Musicality is a loosely used term with many meanings. It can be applied to a small child who chants a nursery rhyme, or to a harmonica player who plays by ear, or to a conductor like Toscanini. Some educators and philosophers believe that musicality is manifested in the technical achievements of musicians. Others believe that technique is…

  18. Formal semantic specifications as implementation blueprints for real-time programming languages

    NASA Technical Reports Server (NTRS)

    Feyock, S.

    1981-01-01

    Formal definitions of language and system semantics provide highly desirable checks on the correctness of implementations of programming languages and their runtime support systems. If these definitions can give concrete guidance to the implementor, major increases in implementation accuracy and decreases in implementation effort can be achieved. It is shown that of the wide variety of available methods the Hgraph (hypergraph) definitional technique (Pratt, 1975), is best suited to serve as such an implementation blueprint. A discussion and example of the Hgraph technique is presented, as well as an overview of the growing body of implementation experience of real-time languages based on Hgraph semantic definitions.

  19. Formal optimization of hovering performance using free wake lifting surface theory

    NASA Technical Reports Server (NTRS)

    Chung, S. Y.

    1986-01-01

    Free wake techniques for performance prediction and optimization of hovering rotor are discussed. The influence functions due to vortex ring, vortex cylinder, and source or vortex sheets are presented. The vortex core sizes of rotor wake vortices are calculated and their importance is discussed. Lifting body theory for finite thickness body is developed for pressure calculation, and hence performance prediction of hovering rotors. Numerical optimization technique based on free wake lifting line theory is presented and discussed. It is demonstrated that formal optimization can be used with the implicit and nonlinear objective or cost function such as the performance of hovering rotors as used in this report.

  20. Description of Jet Breakup

    NASA Technical Reports Server (NTRS)

    Papageorgiou, Demetrios T.

    1996-01-01

    In this article we review recent results on the breakup of cylindrical jets of a Newtonian fluid. Capillary forces provide the main driving mechanism and our interest is in the description of the flow as the jet pinches to form drops. The approach is to describe such topological singularities by constructing local (in time and space) similarity solutions from the governing equations. This is described for breakup according to the Euler, Stokes or Navier-Stokes equations. It is found that slender jet theories can be applied when viscosity is present, but for inviscid jets the local shape of the jet at breakup is most likely of a non-slender geometry. Systems of one-dimensional models of the governing equations are solved numerically in order to illustrate these differences.

  1. Task Description Language

    NASA Technical Reports Server (NTRS)

    Simmons, Reid; Apfelbaum, David

    2005-01-01

    Task Description Language (TDL) is an extension of the C++ programming language that enables programmers to quickly and easily write complex, concurrent computer programs for controlling real-time autonomous systems, including robots and spacecraft. TDL is based on earlier work (circa 1984 through 1989) on the Task Control Architecture (TCA). TDL provides syntactic support for hierarchical task-level control functions, including task decomposition, synchronization, execution monitoring, and exception handling. A Java-language-based compiler transforms TDL programs into pure C++ code that includes calls to a platform-independent task-control-management (TCM) library. TDL has been used to control and coordinate multiple heterogeneous robots in projects sponsored by NASA and the Defense Advanced Research Projects Agency (DARPA). It has also been used in Brazil to control an autonomous airship and in Canada to control a robotic manipulator.

  2. Symmetrical gait descriptions

    NASA Astrophysics Data System (ADS)

    Dunajewski, Adam; Dusza, Jacek J.; Rosado Muñoz, Alfredo

    2014-11-01

    The article presents a proposal for the description of human gait as a periodic and symmetric process. Firstly, the data for researches was obtained in the Laboratory of Group SATI in the School of Engineering of University of Valencia. Then, the periodical model - Mean Double Step (MDS) was made. Finally, on the basis of MDS, the symmetrical models - Left Mean Double Step and Right Mean Double Step (LMDS and RMDS) could be created. The method of various functional extensions was used. Symmetrical gait models can be used to calculate the coefficients of asymmetry at any time or phase of the gait. In this way it is possible to create asymmetry, function which better describes human gait dysfunction. The paper also describes an algorithm for calculating symmetric models, and shows exemplary results based on the experimental data.

  3. Formal, Non-Formal and Informal learning: The Case of Literacy, Essential Skills, and Language Learning in Canada

    ERIC Educational Resources Information Center

    Eaton, Sarah Elaine

    2010-01-01

    This research report investigates the links between formal, non-formal and informal learning and the differences between them. In particular, the report aims to link these notions of learning to literacy and essential skills, as well as the learning of second and other languages in Canada. It builds upon the work of the OECD (n.d.) and Werquin…

  4. YUCCA MOUNTAIN SITE DESCRIPTION

    SciTech Connect

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  5. Older Adults’ Pain Descriptions

    PubMed Central

    McDonald, Deborah Dillon

    2008-01-01

    The purpose of this study was to describe the types of pain information described by older adults with chronic osteoarthritis pain. Pain descriptions were obtained from older adults’ who participated in a posttest only double blind study testing how the phrasing of healthcare practitioners’ pain questions affected the amount of communicated pain information. The 207 community dwelling older adults were randomized to respond to either the open-ended or closed-ended pain question. They viewed and orally responded to a computer displayed videotape of a practitioner asking them the respective pain question. All then viewed and responded to the general follow up question, ““What else can you tell me?” and lastly, “What else can you tell me about your pain, aches, soreness or discomfort?” Audio-taped responses were transcribed and content analyzed by trained, independent raters using 16 a priori criteria from the American Pain Society (2002) Guidelines for the Management of Pain in Osteoarthritis, Rheumatoid Arthritis, and Juvenile Chronic Arthritis. Older adults described important but limited types of information primarily about pain location, timing, and intensity. Pain treatment information was elicited after repeated questioning. Therefore, practitioners need to follow up older adults’ initial pain descriptions with pain questions that promote a more complete pain management discussion. Routine use of a multidimensional pain assessment instrument that measures information such as functional interference, current pain treatments, treatment effects, and side effects would be one way of insuring a more complete pain management discussion with older adults. PMID:19706351

  6. Techniques for Forecasting Air Passenger Traffic

    NASA Technical Reports Server (NTRS)

    Taneja, N.

    1972-01-01

    The basic techniques of forecasting the air passenger traffic are outlined. These techniques can be broadly classified into four categories: judgmental, time-series analysis, market analysis and analytical. The differences between these methods exist, in part, due to the degree of formalization of the forecasting procedure. Emphasis is placed on describing the analytical method.

  7. Leveraging Formal Methods and Fuzzing to Verify Security and Reliability Properties of Large-Scale High-Consequence Systems.

    SciTech Connect

    Ruthruff, Joseph.; Armstrong, Robert C.; Davis, Benjamin Garry; Mayo, Jackson R.; Punnoose, Ratish J.

    2012-09-01

    Formal methods describe a class of system analysis techniques that seek to prove specific propertiesabout analyzed designs, or locate flaws compromising those properties. As an analysis capability,these techniques are the subject of increased interest fromboth internal and external customersof Sandia National Laboratories. Given this lab's other areas of expertise, Sandia is uniquelypositioned to advance the state-of-the-art with respect toseveral research and application areaswithin formal methods. This research project was a one-yeareffort funded by Sandia's CyberSecurity S&T Investment Area in its Laboratory Directed Research & Development program toinvestigate the opportunities for formal methods to impactSandia's present mission areas, morefully understand the needs of the research community in the area of formal methods and whereSandia can contribute, and clarify from those potential research paths those that would best advancethe mission-area interests of Sandia. The accomplishmentsfrom this project reinforce the utilityof formal methods in Sandia, particularly in areas relevantto Cyber Security, and set the stagefor continued Sandia investments to ensure this capabilityis utilized and advanced within thislaboratory to serve the national interest.4

  8. Closed-time-path functional formalism in curved spacetime: Application to cosmological back-reaction problems

    NASA Astrophysics Data System (ADS)

    Calzetta, E.; Hu, B. L.

    1987-01-01

    We discuss the generalization to curved spacetime of a path-integral formalism of quantum field theory based on the sum over paths first going forward in time in the presence of one external source from an in vacuum to a state defined on a hypersurface of constant time in the future, and then backwards in time in the presence of a different source to the same in vacuum. This closed-time-path formalism which generalizes the conventional method based on in-out vacuum persistence amplitudes yields real and causal effective actions, field equations, and expectation values. We apply this method to two problems in semiclassical cosmology. First we study the back reaction of particle production in a radiation-filled Bianchi type-I universe with a conformal scalar field. Unlike the in-out formalism which yields complex geometries the real and causal effective action here yields equations for real effective geometries, with more readily interpretable results. It also provides a clear identification of particle production as a dissipative process in semiclassical theories. In the second problem we calculate the vacuum expectation value of the stress-energy tensor for a nonconformal massive λφ4 theory in a Robertson-Walker universe. This study serves to illustrate the use of Feynman diagrams and higher-loop calculations in this formalism. It also demonstrates the economy of this method in the calculation of expectation values over the mode-sum Bogolubov transformation methods ordinarily applied to matrix elements calculated in the conventional in-out approach. The capability of the closed-time-path formalism of dealing with Feynman, causal, and correlation functions on the same footing makes it a potentially powerful and versatile technique for treating nonequilibrium statistical properties of dynamical systems as in early-Universe quantum processes.

  9. Application of a new dosimetry formalism to volumetric modulated arc therapy (VMAT).

    PubMed

    Rosser, Karen E; Bedford, James L

    2009-12-07

    Volumetric modulated arc therapy (VMAT) offers a challenge to classical dosimetry protocols as the beams are dynamic in orientation and aperture shape and may include small apertures. The aim of this paper is to apply a formalism to VMAT beams that has recently been published by the International Atomic Energy Agency (IAEA) working party to improve the dosimetry for small and non-standard fields. We investigated three possible fields and assessed their suitability as plan class specific reference (pcsr) fields. The factors in the new dosimetry formalism were investigated: the conversion of dose to water from the conventional reference field to the pcsr and then from the pcsr to a treatment plan, using a PTW semiflex chamber, two Farmer chambers and an electron diode. Finally, the dose was compared for Alanine, the new formalism and calculated using Pinnacle(3) (Philips Radiation Oncology Systems) for two typical clinical VMAT beams. Correction factors between the reference field and the pcsr determined with Alanine range from 0.1% to 2.3% for the three pcsr fields. Dose to water measured using the calibrated ionization chambers is less than 2% different to the dose calculated by Pinnacle(3). VMAT planning and delivery procedures have been successfully implemented and a new dosimetry protocol has been investigated for this new technique. Calibration factors for pcsr fields are found to be up to 2.3% different when using the new formalism, compared to using a standard dosimetry protocol. Using the calibration factors determined in the pcsr fields, the ionization chambers and electron diode agree to within 1% with Alanine dosimetry for two clinical VMAT plans. Good agreements between calculations and measurements are found for these two plans when the new formalism is used.

  10. SCORE - A DESCRIPTION.

    ERIC Educational Resources Information Center

    SLACK, CHARLES W.

    REINFORCEMENT AND ROLE-REVERSAL TECHNIQUES ARE USED IN THE SCORE PROJECT, A LOW-COST PROGRAM OF DELINQUENCY PREVENTION FOR HARD-CORE TEENAGE STREET CORNER BOYS. COMMITTED TO THE BELIEF THAT THE BOYS HAVE THE POTENTIAL FOR ETHICAL BEHAVIOR, THE SCORE WORKER FOLLOWS B.F. SKINNER'S THEORY OF OPERANT CONDITIONING AND REINFORCES THE DELINQUENT'S GOOD…

  11. Advanced crew procedures development techniques: Procedures and performance program description

    NASA Technical Reports Server (NTRS)

    Arbet, J. D.; Mangiaracina, A. A.

    1975-01-01

    The Procedures and Performance Program (PPP) for operation in conjunction with the Shuttle Procedures Simulator (SPS) is described. The PPP user interface, the SPS/PPP interface, and the PPP applications software are discussed.

  12. [Description of the two surgical myocardial revascularisation techniques].

    PubMed

    Ouazzani, Marouane; Sinquet, Jean Claude; Frapier, Jean Marc; Rouvière, Philippe; Albat, Bernard; Demaria, Roland

    2015-03-01

    A coronary artery bypass involves taking blood vessels from another part of the patient's body to bypass one or several major coronary stenoses. Coronary artery bypass using cardiopulmonary bypass and off-pump coronary artery bypass are the two methods used to revascularise the heart after a myocardial infarction.

  13. Correlates of formal reasoning: Content and problem effects

    NASA Astrophysics Data System (ADS)

    Linn, Marcia C.; Pulos, Steven; Gans, Adrienne

    Piaget's structural theory of formal thought suggests that a general construct of formal reasoning exists. The content of the task and type of problem employed are often ignored in Piagetian based studies but are important for generalizing findings to other studies and to educational problems. The study reported here examines content and problem effects of formal thought in 13-year-old adolescents. Specifically, three controlling variables tasks with different content and two question type tests (analysis and controlling questions) were administered to 120 seventh graders. Ability measures and personality dimensions associated with formal reasoning in the literature are used to clarify what formal reasoning is and how content and problem type are involved in formal reasoning. Significant main effects were found for problem and content effects (p = 0.001), and a significant interaction was found between the two (p = 0.001). Across the three tasks general ability, field dependency, and locus of control were consistently and significantly related to the controlling questions. However, only measures of field dependency were related to the analysis questions. Combinations of ability and personality factors were found to be uniquely related to each task, within each question type. Results have implications for a theory of formal thought and the teaching of the controlling variables strategy.

  14. What do tests of formal reasoning actually measure?

    NASA Astrophysics Data System (ADS)

    Lawson, Anton E.

    Tests of formal operational reasoning derived from Piagetian theory have been found to be effective predictors of academic achievement. Yet Piaget's theory regarding the underlying nature of formal operations and their employment in specific contexts has run into considerable empirical difficulty. The primary purpose of this study was to present the core of an alternative theory of the nature of advanced scientific reasoning. That theory, referred to as the multiple-hypothesis theory, argues that tests of formal operational reasoning actually measure the extent to which persons have acquired the ability to initiate reasoning with more than one specific antecedent condition, or if they are unable to imagine more than one antecedent condition, they are aware that more than one is possible; therefore conclusions that are drawn are tempered by this possibility. As a test of this multiple-hypothesis theory of advanced reasoning and the contrasting Piagetian theory of formal operations, a sample of 922 college students were first classified as concrete operational, transitional, or formal operational, based upon responses to standard Piagetian measures of formal operational reasoning. They were then administered seven logic tasks. Actual response patterns to the tasks were analyzed and found to be similar to predicted response patterns derived from the multiple-hypothesis theory and were different from those predicted by Piagetian theory. Therefore, support was obtained for the multiple-hypothesis theory. The terms intuitive and reflective were suggested to replace the terms concrete operational and formal operational to refer to persons at varying levels of intellectual development.

  15. A review of research on formal reasoning and science teaching

    NASA Astrophysics Data System (ADS)

    Lawson, Anton E.

    A central purpose of education is to improve students' reasoning abilities. The present review examines research in developmental psychology and science education that has attempted to assess the validity of Piaget's theory of formal thought and its relation to educational practice. Should a central objective of schools be to help students become formal thinkers? To answer this question research has focused on the following subordinate questions: (1) What role does biological maturation play in the development of formal reasoning? (2) Are Piaget's formal tasks reliable and valid? (3) Does formal reasoning constitute a unified and general mode of intellectual functioning? (4) How does the presence or absence of formal reasoning affect school achievement? (5) Can formal reasoning be taught? (6) What is the structural or functional nature of advanced reasoning? The general conclusion drawn is that although Piaget's work and that which has sprung from it leaves a number of unresolved theoretical and methodological problems, it provides an important background from which to make substantial progress toward a most significant educational objective.All our dignity lies in thought. By thought we must elevate ourselves, not by space and time which we can not fill. Let us endeavor then to think well; therein lies the principle of morality. Blaise Pascal 1623-1662.

  16. Proceedings of the Second NASA Formal Methods Symposium

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar (Editor)

    2010-01-01

    This publication contains the proceedings of the Second NASA Formal Methods Symposium sponsored by the National Aeronautics and Space Administration and held in Washington D.C. April 13-15, 2010. Topics covered include: Decision Engines for Software Analysis using Satisfiability Modulo Theories Solvers; Verification and Validation of Flight-Critical Systems; Formal Methods at Intel -- An Overview; Automatic Review of Abstract State Machines by Meta Property Verification; Hardware-independent Proofs of Numerical Programs; Slice-based Formal Specification Measures -- Mapping Coupling and Cohesion Measures to Formal Z; How Formal Methods Impels Discovery: A Short History of an Air Traffic Management Project; A Machine-Checked Proof of A State-Space Construction Algorithm; Automated Assume-Guarantee Reasoning for Omega-Regular Systems and Specifications; Modeling Regular Replacement for String Constraint Solving; Using Integer Clocks to Verify the Timing-Sync Sensor Network Protocol; Can Regulatory Bodies Expect Efficient Help from Formal Methods?; Synthesis of Greedy Algorithms Using Dominance Relations; A New Method for Incremental Testing of Finite State Machines; Verification of Faulty Message Passing Systems with Continuous State Space in PVS; Phase Two Feasibility Study for Software Safety Requirements Analysis Using Model Checking; A Prototype Embedding of Bluespec System Verilog in the PVS Theorem Prover; SimCheck: An Expressive Type System for Simulink; Coverage Metrics for Requirements-Based Testing: Evaluation of Effectiveness; Software Model Checking of ARINC-653 Flight Code with MCP; Evaluation of a Guideline by Formal Modelling of Cruise Control System in Event-B; Formal Verification of Large Software Systems; Symbolic Computation of Strongly Connected Components Using Saturation; Towards the Formal Verification of a Distributed Real-Time Automotive System; Slicing AADL Specifications for Model Checking; Model Checking with Edge-valued Decision Diagrams

  17. A Formalization of HIPAA for a Medical Messaging System

    NASA Astrophysics Data System (ADS)

    Lam, Peifung E.; Mitchell, John C.; Sundaram, Sharada

    The complexity of regulations in healthcare, financial services, and other industries makes it difficult for enterprises to design and deploy effective compliance systems. We believe that in some applications, it may be practical to support compliance by using formalized portions of applicable laws to regulate business processes that use information systems. In order to explore this possibility, we use a stratified fragment of Prolog with limited use of negation to formalize a portion of the US Health Insurance Portability and Accountability Act (HIPAA). As part of our study, we also explore the deployment of our formalization in a prototype hospital Web portal messaging system.

  18. Multisymplectic Lagrangian and Hamiltonian Formalisms of Classical Field Theories

    NASA Astrophysics Data System (ADS)

    Román-Roy, Narciso

    2009-11-01

    This review paper is devoted to presenting the standard multisymplectic formulation for describing geometrically classical field theories, both the regular and singular cases. First, the main features of the Lagrangian formalism are revisited and, second, the Hamiltonian formalism is constructed using Hamiltonian sections. In both cases, the variational principles leading to the Euler-Lagrange and the Hamilton-De Donder-Weyl equations, respectively, are stated, and these field equations are given in different but equivalent geometrical ways in each formalism. Finally, both are unified in a new formulation (which has been developed in the last years), following the original ideas of Rusk and Skinner for mechanical systems.

  19. A Formal Approach to Analyzing Interference Problems in Aspect-Oriented Designs

    NASA Astrophysics Data System (ADS)

    Chen, Xin; Ye, Nan; Ding, Wenxu

    Interference problems in aspect-oriented designs refer to the undesired interference between aspects and base programs that can lead to the emergence of unexpected behaviors, which do harm to the correctness of the entire system. We present a rigorous approach to analyzing the interference problems in aspect-oriented designs. Formal representations of classes and aspects are defined in terms of designs in UTP, while the weaving techniques in AOP are interpreted as the compositions of corresponding formal models. Conflicts between an aspect and base programs as well as between two aspects can be detected by calculating the weakest preconditions. Furthermore, the calculation also provides informative guidelines on how to solve the conflicts it found. Early detecting and removing conflicts in aspect-oriented design models can improve their qualities and save plenty of costs.

  20. Microgravity Environment Description Handbook

    NASA Technical Reports Server (NTRS)

    DeLombard, Richard; McPherson, Kevin; Hrovat, Kenneth; Moskowitz, Milton; Rogers, Melissa J. B.; Reckart, Timothy

    1997-01-01

    The Microgravity Measurement and Analysis Project (MMAP) at the NASA Lewis Research Center (LeRC) manages the Space Acceleration Measurement System (SAMS) and the Orbital Acceleration Research Experiment (OARE) instruments to measure the microgravity environment on orbiting space laboratories. These laboratories include the Spacelab payloads on the shuttle, the SPACEHAB module on the shuttle, the middeck area of the shuttle, and Russia's Mir space station. Experiments are performed in these laboratories to investigate scientific principles in the near-absence of gravity. The microgravity environment desired for most experiments would have zero acceleration across all frequency bands or a true weightless condition. This is not possible due to the nature of spaceflight where there are numerous factors which introduce accelerations to the environment. This handbook presents an overview of the major microgravity environment disturbances of these laboratories. These disturbances are characterized by their source (where known), their magnitude, frequency and duration, and their effect on the microgravity environment. Each disturbance is characterized on a single page for ease in understanding the effect of a particular disturbance. The handbook also contains a brief description of each laboratory.

  1. The dynamics of stock exchange based on the formalism of weak continuous quantum measurement

    NASA Astrophysics Data System (ADS)

    Melnyk, S.; Tuluzov, I.

    2010-07-01

    The problem of measurement in economic models and the possibility of their quantum-mechanical description are considered. It is revealed that the apparent paradox of such a description is associated with a priori requirement of conformity of the model to all the alternatives of free choice of the observer. The measurement of the state of a trader on a stock exchange is formally defined as his responses to the proposals of sale at a fixed price. It is shown that an analogue of Bell's inequalities for this measurement model is violated at the most general assumptions related to the strategy of the trader and requires a quantum-mechanical description of the dynamics of his condition. In the framework of the theory of weak continuous quantum measurements, the equation of stock price dynamics and the quantum-mechanical generalization of the F. Black and M. Scholes model for pricing options are obtained. The fundamental distinctions between the obtained model and the classical one are discussed.

  2. Trusting Description: Authenticity, Accountability, and Archival Description Standards

    ERIC Educational Resources Information Center

    MacNeil, Heather

    2009-01-01

    It has been suggested that one of the purposes of archival description is to establish grounds for presuming the authenticity of the records being described. The article examines the implications of this statement by examining the relationship between and among authenticity, archival description, and archival accountability, assessing how this…

  3. Dominant partition method. [based on a wave function formalism

    NASA Technical Reports Server (NTRS)

    Dixon, R. M.; Redish, E. F.

    1979-01-01

    By use of the L'Huillier, Redish, and Tandy (LRT) wave function formalism, a partially connected method, the dominant partition method (DPM) is developed for obtaining few body reductions of the many body problem in the LRT and Bencze, Redish, and Sloan (BRS) formalisms. The DPM maps the many body problem to a fewer body one by using the criterion that the truncated formalism must be such that consistency with the full Schroedinger equation is preserved. The DPM is based on a class of new forms for the irreducible cluster potential, which is introduced in the LRT formalism. Connectivity is maintained with respect to all partitions containing a given partition, which is referred to as the dominant partition. Degrees of freedom corresponding to the breakup of one or more of the clusters of the dominant partition are treated in a disconnected manner. This approach for simplifying the complicated BRS equations is appropriate for physical problems where a few body reaction mechanism prevails.

  4. Understanding visualization: a formal approach using category theory and semiotics.

    PubMed

    Vickers, Paul; Faith, Joe; Rossiter, Nick

    2013-06-01

    This paper combines the vocabulary of semiotics and category theory to provide a formal analysis of visualization. It shows how familiar processes of visualization fit the semiotic frameworks of both Saussure and Peirce, and extends these structures using the tools of category theory to provide a general framework for understanding visualization in practice, including: Relationships between systems, data collected from those systems, renderings of those data in the form of representations, the reading of those representations to create visualizations, and the use of those visualizations to create knowledge and understanding of the system under inspection. The resulting framework is validated by demonstrating how familiar information visualization concepts (such as literalness, sensitivity, redundancy, ambiguity, generalizability, and chart junk) arise naturally from it and can be defined formally and precisely. This paper generalizes previous work on the formal characterization of visualization by, inter alia, Ziemkiewicz and Kosara and allows us to formally distinguish properties of the visualization process that previous work does not.

  5. Why are Formal Methods Not Used More Widely?

    NASA Technical Reports Server (NTRS)

    Knight, John C.; DeJong, Colleen L.; Gibble, Matthew S.; Nakano, Luis G.

    1997-01-01

    Despite extensive development over many years and significant demonstrated benefits, formal methods remain poorly accepted by industrial practitioners. Many reasons have been suggested for this situation such as a claim that they extent the development cycle, that they require difficult mathematics, that inadequate tools exist, and that they are incompatible with other software packages. There is little empirical evidence that any of these reasons is valid. The research presented here addresses the question of why formal methods are not used more widely. The approach used was to develop a formal specification for a safety-critical application using several specification notations and assess the results in a comprehensive evaluation framework. The results of the experiment suggests that there remain many impediments to the routine use of formal methods.

  6. Rayleigh-Lagrange formalism for classical dissipative systems.

    PubMed

    Virga, Epifanio G

    2015-01-01

    It is often believed that the Rayleigh-Lagrange formalism for classical dissipative systems is unable to encompass forces described by nonlinear functions of the velocities. Here we show that this is indeed a misconception.

  7. Formal methods and digital systems validation for airborne systems

    NASA Technical Reports Server (NTRS)

    Rushby, John

    1993-01-01

    This report has been prepared to supplement a forthcoming chapter on formal methods in the FAA Digital Systems Validation Handbook. Its purpose is as follows: to outline the technical basis for formal methods in computer science; to explain the use of formal methods in the specification and verification of software and hardware requirements, designs, and implementations; to identify the benefits, weaknesses, and difficulties in applying these methods to digital systems used on board aircraft; and to suggest factors for consideration when formal methods are offered in support of certification. These latter factors assume the context for software development and assurance described in RTCA document DO-178B, 'Software Considerations in Airborne Systems and Equipment Certification,' Dec. 1992.

  8. Experiences Using Lightweight Formal Methods for Requirements Modeling

    NASA Technical Reports Server (NTRS)

    Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David

    1997-01-01

    This paper describes three case studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, formal methods enhanced the existing verification and validation processes, by testing key properties of the evolving requirements, and helping to identify weaknesses. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.

  9. A logarithmic correction in the entropy functional formalism

    NASA Astrophysics Data System (ADS)

    Hammad, Fayçal; Faizal, Mir

    2016-04-01

    The entropy functional formalism allows one to recover general relativity, modified gravity theories, as well as the Bekenstein-Hawking entropy formula. In most approaches to quantum gravity, the Bekenstein-Hawking’s entropy formula acquires a logarithmic correction term. As such terms occur almost universally in most approaches to quantum gravity, we analyze the effect of such terms on the entropy functional formalism. We demonstrate that the leading correction to the micro-canonical entropy in the entropy functional formalism can be used to recover modified theories of gravity already obtained with an uncorrected micro-canonical entropy. Furthermore, since the entropy functional formalism reproduces modified gravity, the rise of gravity-dependent logarithmic corrections turns out to be one way to impose constraints on these theories of modified gravity. The constraints found here for the simple case of an ℱ(R)-gravity are the same as those obtained in the literature from cosmological considerations.

  10. Bridging the Gap Between Formal and Informal Science Education

    NASA Astrophysics Data System (ADS)

    Hamel, C.

    2001-12-01

    Formal learning skills are enhanced throughout our daily lives through the public media, (television, newspapers, radio); while hiking our favorite park; or by visiting a museum or science center. Over the past few years the informal science community has started to bridge the gap with the formal education community. Although few informal education organizations have established set curriculum guidelines, many have adapted the use of the National Science Standards. In so doing, these organizations have raised their level of professionalism. Many formal school programs are now actively seeking collaborative science education programs to enhance and expand their hands-on, inquiry based curriculia through informal science organizations. This paper/presentation will address my current research within this field. I will discuss selected federal science agencies education and outreach efforts. Key points will include media useage, age of target audiences, credentials of interpretation staff, and level(s) of collaboration with formal schools.

  11. Formal Approaches to Ensuring the Safety of Space Software

    NASA Technical Reports Server (NTRS)

    Denney, Ewen; Fischer, Bernd

    2006-01-01

    A viewgraph describing formal approaches taken to assure the safety of space software is presented. The topics include: 1) Certifiable Program Generation; 2) Certification Framework; 3) Annotation Generation; 4) Experiments; and 5) Future Work.

  12. Using formal specification in the Guidance and Control Software (GCS) experiment. Formal design and verification technology for life critical systems

    NASA Technical Reports Server (NTRS)

    Weber, Doug; Jamsek, Damir

    1994-01-01

    The goal of this task was to investigate how formal methods could be incorporated into a software engineering process for flight-control systems under DO-178B and to demonstrate that process by developing a formal specification for NASA's Guidance and Controls Software (GCS) Experiment. GCS is software to control the descent of a spacecraft onto a planet's surface. The GCS example is simplified from a real example spacecraft, but exhibits the characteristics of realistic spacecraft control software. The formal specification is written in Larch.

  13. Formal Foundations for the Specification of Software Architecture.

    DTIC Science & Technology

    1995-03-01

    AFIT/DSG/ENG/95M-01 "DTIC ELECTE AUG 1 5 1995 F FORMAL FOUNDATIONS FOR THE SPECIFICATION OF SOFTWARE ARCHITECTURE DISSERTATION Mark James Gerken...Captain, USAF AFIT/DSG/ENG/95M-O1 19950811 050 DTI QUALIT1 CTD 5 Approved for public release; distribution unlimited AFIT/DSG/ENG/95M-01 FORMAL...4-13 4.4 Summary ..................................... 4-15 V. Mathematical Foundations ................................... 5 -1 5.1

  14. Skinner-Rusk unified formalism for higher-order systems

    NASA Astrophysics Data System (ADS)

    Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso

    2012-07-01

    The Lagrangian-Hamiltonian unified formalism of R. Skinner and R. Rusk was originally stated for autonomous dynamical systems in classical mechanics. It has been generalized for non-autonomous first-order mechanical systems, first-order and higher-order field theories, and higher-order autonomous systems. In this work we present a generalization of this formalism for higher-order non-autonomous mechanical systems.

  15. Bridging the Semantic Gap Between Heterogeneous Modeling Formalisms and FMI

    DTIC Science & Technology

    2014-04-25

    Bridging the Semantic Gap Between Heterogeneous Modeling Formalisms and FMI Stavros Tripakis David Broman Electrical Engineering and Computer...Modeling Formalisms and FMI 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...SUPPLEMENTARY NOTES 14. ABSTRACT FMI (Functional Mockup Interface) is a standard for exchanging and co-simulating model components (called FMUs) coming

  16. Formal functional test designs with a test representation language

    NASA Technical Reports Server (NTRS)

    Hops, J. M.

    1993-01-01

    The application of the category-partition method to the test design phase of hardware, software, or system test development is discussed. The method provides a formal framework for reducing the total number of possible test cases to a minimum logical subset for effective testing. An automatic tool and a formal language were developed to implement the method and produce the specification of test cases.

  17. FORMED: Bringing Formal Methods to the Engineering Desktop

    DTIC Science & Technology

    2016-02-01

    other languages and tools, such as Coq. While the language was easy to pick up, based on Lisp, the tools took a while to learn . Documentation...Tree DSL Domain Specific Language FORMED Formal Methods Engineering Desktop IDE Integrated Development Environment OCL Object Constraint Language ... integrates formal verification into software design and development by precisely defining semantics for a restricted subset of the Unified Modeling

  18. Formalizing the definition of meta-analysis in Molecular Ecology.

    PubMed

    ArchMiller, Althea A; Bauer, Eric F; Koch, Rebecca E; Wijayawardena, Bhagya K; Anil, Ammu; Kottwitz, Jack J; Munsterman, Amelia S; Wilson, Alan E

    2015-08-01

    Meta-analysis, the statistical synthesis of pertinent literature to develop evidence-based conclusions, is relatively new to the field of molecular ecology, with the first meta-analysis published in the journal Molecular Ecology in 2003 (Slate & Phua 2003). The goal of this article is to formalize the definition of meta-analysis for the authors, editors, reviewers and readers of Molecular Ecology by completing a review of the meta-analyses previously published in this journal. We also provide a brief overview of the many components required for meta-analysis with a more specific discussion of the issues related to the field of molecular ecology, including the use and statistical considerations of Wright's FST and its related analogues as effect sizes in meta-analysis. We performed a literature review to identify articles published as 'meta-analyses' in Molecular Ecology, which were then evaluated by at least two reviewers. We specifically targeted Molecular Ecology publications because as a flagship journal in this field, meta-analyses published in Molecular Ecology have the potential to set the standard for meta-analyses in other journals. We found that while many of these reviewed articles were strong meta-analyses, others failed to follow standard meta-analytical techniques. One of these unsatisfactory meta-analyses was in fact a secondary analysis. Other studies attempted meta-analyses but lacked the fundamental statistics that are considered necessary for an effective and powerful meta-analysis. By drawing attention to the inconsistency of studies labelled as meta-analyses, we emphasize the importance of understanding the components of traditional meta-analyses to fully embrace the strengths of quantitative data synthesis in the field of molecular ecology.

  19. Adolescent thinking ála Piaget: The formal stage.

    PubMed

    Dulit, E

    1972-12-01

    Two of the formal-stage experiments of Piaget and Inhelder, selected largely for their closeness to the concepts defining the stage, were replicated with groups of average and gifted adolescents. This report describes the relevant Piagetian concepts (formal stage, concrete stage) in context, gives the methods and findings of this study, and concludes with a section discussing implications and making some reformulations which generally support but significantly qualify some of the central themes of the Piaget-Inhelder work. Fully developed formal-stage thinking emerges as far from commonplace among normal or average adolescents (by marked contrast with the impression created by the Piaget-Inhelder text, which chooses to report no middle or older adolescents who function at less than fully formal levels). In this respect, the formal stage differs appreciably from the earlier Piagetian stages, and early adolescence emerges as the age for which a "single path" model of cognitive development becomes seriously inadequate and a more complex model becomes essential. Formal-stage thinking seems best conceptualized, like most other aspects of psychological maturity, as a potentiality only partially attained by most and fully attained only by some.

  20. Logic synthesis from DDL description

    NASA Technical Reports Server (NTRS)

    Shiva, S. G.

    1980-01-01

    The implementation of DDLTRN and DDLSIM programs on SEL-2 computer system is reported. These programs were tested with DDL descriptions of various complexity. An algorithm to synthesize the combinational logic using the cells available in the standard IC cell library was formulated. The algorithm is implemented as a FORTRAN program and a description of the program is given.