WorldWideScience

Sample records for models general guidelines

  1. Advanced human-system interface design review guideline. General evaluation model, technical development, and guideline description

    International Nuclear Information System (INIS)

    O'Hara, J.M.

    1994-07-01

    Advanced control rooms will use advanced human-system interface (HSI) technologies that may have significant implications for plant safety in that they will affect the operator's overall role in the system, the method of information presentation, and the ways in which operators interact with the system. The U.S. Nuclear Regulatory Commission (NRC) reviews the HSI aspects of control rooms to ensure that they are designed to good human factors engineering principles and that operator performance and reliability are appropriately supported to protect public health and safety. The principal guidance available to the NRC, however, was developed more than ten years ago, well before these technological changes. Accordingly, the human factors guidance needs to be updated to serve as the basis for NRC review of these advanced designs. The purpose of this project was to develop a general approach to advanced HSI review and the human factors guidelines to support NRC safety reviews of advanced systems. This two-volume report provides the results of the project. Volume I describes the development of the Advanced HSI Design Review Guideline (DRG) including (1) its theoretical and technical foundation, (2) a general model for the review of advanced HSIs, (3) guideline development in both hard-copy and computer-based versions, and (4) the tests and evaluations performed to develop and validate the DRG. Volume I also includes a discussion of the gaps in available guidance and a methodology for addressing them. Volume 2 provides the guidelines to be used for advanced HSI review and the procedures for their use

  2. Advanced human-system interface design review guideline. General evaluation model, technical development, and guideline description

    Energy Technology Data Exchange (ETDEWEB)

    O`Hara, J.M.

    1994-07-01

    Advanced control rooms will use advanced human-system interface (HSI) technologies that may have significant implications for plant safety in that they will affect the operator`s overall role in the system, the method of information presentation, and the ways in which operators interact with the system. The U.S. Nuclear Regulatory Commission (NRC) reviews the HSI aspects of control rooms to ensure that they are designed to good human factors engineering principles and that operator performance and reliability are appropriately supported to protect public health and safety. The principal guidance available to the NRC, however, was developed more than ten years ago, well before these technological changes. Accordingly, the human factors guidance needs to be updated to serve as the basis for NRC review of these advanced designs. The purpose of this project was to develop a general approach to advanced HSI review and the human factors guidelines to support NRC safety reviews of advanced systems. This two-volume report provides the results of the project. Volume I describes the development of the Advanced HSI Design Review Guideline (DRG) including (1) its theoretical and technical foundation, (2) a general model for the review of advanced HSIs, (3) guideline development in both hard-copy and computer-based versions, and (4) the tests and evaluations performed to develop and validate the DRG. Volume I also includes a discussion of the gaps in available guidance and a methodology for addressing them. Volume 2 provides the guidelines to be used for advanced HSI review and the procedures for their use.

  3. Description of a chronic heart failure service model and review of pharmacotherapy in a district general hospital in comparison to Scottish Intercollegiate Guideline Network (SIGN) guidelines.

    Science.gov (United States)

    Ogundipe, O A; Cordina, J; Norris, C A

    2008-08-01

    The Scottish Intercollegiate Guidelines Network (SIGN) guideline 95 on the management of chronic heart failure (CHF) was published in February 2007, superseding SIGN guideline 35 of February 1999. The guideline promotes evidence based management of CHE. To describe an existing service model and to review our level of concordance with SIGN guidelines. We describe a model of a CHF service based in a district general hospital (DGH) in Scotland. We conducted a retrospective review on consecutive new referrals between August and November 2002, and a prospective review of new attendances between September 2005 and January 2006. In 2002 and 2005/6, 49 and 45 patients were reviewed respectively, with 26 and 28 patients showing left ventricular systolic dysfunction on echocardiography. Median ages of patients were 81 and 79 years respectively. Angiotensin Converting Enzyme Inhibitor (ACEI) or Angiotensin II Receptor Blocker (AIIRB) therapy was in use in 23 (88.5%) and 24 (85.7%) patients respectively. The use of beta-blockers, digoxin and spironolactone was shown to have improved between both reviews. We have been able to demonstrate an improving level of concordance with SIGN guidelines in a district general hospital (DGH) heart failure service model run by care of the elderly physicians and supported by specialist nurses.

  4. Guidelines for computer security in general practice

    Directory of Open Access Journals (Sweden)

    Peter Schattner

    2007-06-01

    Conclusions This paper maps out a process for developing computer security guidelines for general practice. The specific content will vary in different countries according to their levels of adoption of IT, and cultural, technical and other health service factors. Making these guidelines relevant to local contexts should help maximise their uptake.

  5. Factors influencing adherence to guidelines in general practice

    NARCIS (Netherlands)

    Stewart, RE; Vroegop, S; van der Werf, GT; Meyboom-de Jong, B; Kamps, G.

    2003-01-01

    Objectives: To identify and assess the effects of general practitioner and patient characteristics on global adherence to pharmacotherapeutic guidelines. Methods: In a cross-sectional study in the northern Netherlands, a two-level multilevel model was applied to patients (n = 269,067) in 190

  6. Adherence to COPD guidelines in general practice

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Sørensen, Tina Brandt; Højmark, Torben Brunse

    2013-01-01

    BACKGROUND: The general practitioner (GP) is often the first healthcare contact for patients with chronic obstructive pulmonary disease (COPD). AIMS: To determine whether participating in a standardised educational programme delivered in the GP's own practice is associated with adherence to COPD...... guidelines. METHODS: A nationwide register-based observational before and after study was undertaken with a control group of propensity-matched practices (follow-up period 6 months). COPD was defined as age 40+ years and at least two prescriptions for inhaled medication. The educational programme consisted...... were used to compare the rate of spirometry testing, preventive consultations, and influenza vaccinations provided to COPD patients and the rate of spirometry testing in non-COPD individuals, assumed to reflect diagnostic activity. RESULTS: Data for 102 participating GP practices were analysed...

  7. Adherence to cancer treatment guidelines: influence of general and cancer-specific guideline characteristics.

    NARCIS (Netherlands)

    Heins, M.J.; Jong, J.D. de; Spronk, I.; Ho, V.K.; Brink, M.; Korevaar, J.C.

    2017-01-01

    Background: Guideline adherence remains a challenge in clinical practice, despite guidelines’ ascribed potential to improve patient outcomes. We studied the level of adherence to recommendations from Dutch national cancer treatment guidelines, and the influence of general and

  8. Guideline Knowledge Representation Model (GLIKREM)

    Czech Academy of Sciences Publication Activity Database

    Buchtela, David; Peleška, Jan; Veselý, Arnošt; Zvárová, Jana; Zvolský, Miroslav

    2008-01-01

    Roč. 4, č. 1 (2008), s. 17-23 ISSN 1801-5603 R&D Projects: GA MŠk(CZ) 1M06014 Institutional research plan: CEZ:AV0Z10300504 Keywords : knowledge representation * GLIF model * guidelines Subject RIV: IN - Informatics, Computer Science http://www.ejbi.org/articles/200812/34/1.html

  9. Tailoring Earned Value Management. General Guidelines

    National Research Council Canada - National Science Library

    2002-01-01

    Partial Contents: General Principles, A Spectrum of Implementation, OMB Guidance, A Special Note about DOD, Risk Factors to Consider, How can EVMS be tailored, Tailor EVMS to Inherent Risk, Application Thresholds-DoD...

  10. General guidelines for biomedical software development.

    Science.gov (United States)

    Silva, Luis Bastiao; Jimenez, Rafael C; Blomberg, Niklas; Luis Oliveira, José

    2017-01-01

    Most bioinformatics tools available today were not written by professional software developers, but by people that wanted to solve their own problems, using computational solutions and spending the minimum time and effort possible, since these were just the means to an end. Consequently, a vast number of software applications are currently available, hindering the task of identifying the utility and quality of each. At the same time, this situation has hindered regular adoption of these tools in clinical practice. Typically, they are not sufficiently developed to be used by most clinical researchers and practitioners. To address these issues, it is necessary to re-think how biomedical applications are built and adopt new strategies that ensure quality, efficiency, robustness, correctness and reusability of software components. We also need to engage end-users during the development process to ensure that applications fit their needs. In this review, we present a set of guidelines to support biomedical software development, with an explanation of how they can be implemented and what kind of open-source tools can be used for each specific topic.

  11. Military Handbook: General Guidelines for Electronic Equipment

    Science.gov (United States)

    1995-04-28

    remainder of the equipment and are separately protected by nonbypassabLe interlocks. (An example of an equipment where such compartmentalizatlon is desirable...substances capable of holding materials together by surface attachment. Adhesive is a general term and includes, among others, cement, glue, mucilage and...impact and peeling. 23-1 MIL-HDBK-454, 5.4 Structural compatibility. Adhesives which are not compatible structurally should be avoided. For example , a

  12. Maintaining formal models of living guidelines efficiently

    NARCIS (Netherlands)

    Seyfang, Andreas; Martínez-Salvador, Begoña; Serban, Radu; Wittenberg, Jolanda; Miksch, Silvia; Marcos, Mar; Ten Teije, Annette; Rosenbrand, Kitty C J G M

    2007-01-01

    Translating clinical guidelines into formal models is beneficial in many ways, but expensive. The progress in medical knowledge requires clinical guidelines to be updated at relatively short intervals, leading to the term living guideline. This causes potentially expensive, frequent updates of the

  13. Hemodialysis in children: general practical guidelines.

    Science.gov (United States)

    Fischbach, M; Edefonti, A; Schröder, C; Watson, A

    2005-08-01

    Over the past 20 years children have benefited from major improvements in both technology and clinical management of dialysis. Morbidity during dialysis sessions has decreased with seizures being exceptional and hypotensive episodes rare. Pain and discomfort have been reduced with the use of chronic internal jugular venous catheters and anesthetic creams for fistula puncture. Non-invasive technologies to assess patient target dry weight and access flow can significantly reduce patient morbidity and health care costs. The development of urea kinetic modeling enables calculation of the dialysis dose delivery, Kt/V, and an indirect assessment of the intake. Nutritional assessment and support are of major importance for the growing child. Even if the validity of these "urea only" data is questioned, their analysis provides information useful for follow-up. Newer machines provide more precise control of ultrafiltration by volumetric assessment and continuous blood volume monitoring during dialysis sessions. Buffered bicarbonate solutions are now standard and more biocompatible synthetic membranes and specific small size material dialyzers and tubing have been developed for young infants. More recently, the concept of "ultrapure" dialysate, i.e. free from microbiological contamination and endotoxins, has developed. This will enable the use of hemodiafiltration, especially with the on-line option, which has many theoretical advantages and should be considered in the case of maximum/optimum dialysis need. Although the optimum dialysis dose requirement for children remains uncertain, reports of longer duration and/or daily dialysis show they are more effective for phosphate control than conventional hemodialysis and should be considered at least for some high-risk patients with cardiovascular impairment. In children hemodialysis has to be individualized and viewed as an "integrated therapy" considering their long-term exposure to chronic renal failure treatment. Dialysis is

  14. Strategy Guideline: Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-24

    The Strategy Guideline describes how to model and interpret results of models for above grade walls. The Measure Guideline analyzes the failure thresholds and criteria for above grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Warme Und Feuchte Instationar) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  15. Guidelines prescribed by general practitioners to patients with acute ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the guidelines prescribed by general practitioners (GPs) to patients with acute low back pain (ALBP) regarding 'return to work'. Methods: A systematic sample of 212 GPs, selected from a list supplied by the Health Professions Council of South Africa (HPCSA), was selected to complete ...

  16. 22 CFR 305.1 - Purpose and general guideline.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Purpose and general guideline. 305.1 Section 305.1 Foreign Relations PEACE CORPS ELIGIBILITY AND STANDARDS FOR PEACE CORPS VOLUNTEER SERVICE § 305.1... taken into consideration, nor shall there be any discrimination against any person on account of race...

  17. Subsystem Design Guidelines for Extensible General-Purpose Software

    NARCIS (Netherlands)

    Grefen, P.W.P.J.; Wieringa, Roelf J.; Magee, J.N.; Perry, D.E.

    1998-01-01

    We discuss subsystem design for extensible general-purpose information systemswe extract guidelines from a case study of the redesign and extension of an advanced workflow management system and place them into the context of existing software engineering research. Key aspect is the distinction

  18. Guidelines for reducing image retakes of general digital radiography

    Directory of Open Access Journals (Sweden)

    Chih-Sheng Lin

    2016-04-01

    Full Text Available Image retake of radiological examinations not only increases the risk of radiation exposure of the patients, but also wastes the medical resource and degrades the quality of services of the hospitals. This study aimed at discovering factors affecting image retake of general digital radiography for setting guidelines to reduce the image retaking rate. A total of 98,503 general X-ray images retrieved from the picture archiving and communication system database of a medical center in central Taiwan were analyzed. The results showed that the total retaking rate was 4.89% with the position error (56.05% was the main factor causing image retakes and chest examination showed the highest frequency (1544 cases. On the other hand, skull/face exhibited the highest retaking rate (9.81% among various types of examinations. After discovering the factors affecting the image retaking rate, suitable guidelines were proposed and introduced. The image retake rate had been significantly reduced to 4.38% and 3.57% 1 month and 6 months, respectively, after the introduction of guidelines. In conclusion, image retake analysis is a quality indicator and is effective for quality assurance of digital radiology. Regular analysis of image retake can find factors inducing image retake and is useful for designing guidelines to reduce the image retake rate.

  19. Comparison of Five Major Guidelines for Statin Use in Primary Prevention in a Contemporary General Population

    DEFF Research Database (Denmark)

    Mortensen, Martin Bødtker; Nordestgaard, Børge Grønne

    2018-01-01

    : Observational study of actual ASCVD events during 10 years, followed by a modeling study to estimate the effectiveness of different guidelines. Setting: The Copenhagen General Population Study. Participants: 45 750 Danish persons aged 40 to 75 years who did not use statins and did not have ASCVD at baseline...... recommending that more persons use statins for primary prevention of ASCVD should prevent more events than guidelines recommending use by fewer persons. Primary Funding Source: Copenhagen University Hospital....

  20. Scandinavian clinical practice guidelines on general anaesthesia for emergency situations

    DEFF Research Database (Denmark)

    Gadegaard Jensen, Anders; Callesen, T; Hagemo, J S

    2010-01-01

    Emergency patients need special considerations and the number and severity of complications from general anaesthesia can be higher than during scheduled procedures. Guidelines are therefore needed. The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care...... Medicine appointed a working group to develop guidelines based on literature searches to assess evidence, and a consensus meeting was held. Consensus opinion was used in the many topics where high-grade evidence was unavailable. The recommendations include the following: anaesthesia for emergency patients...... breathing for 3 min or eight deep breaths over 60 s and oxygen flow 10 l/min should be used. Pre-oxygenation in the obese patients should be performed in the head-up position. The use of cricoid pressure is not considered mandatory, but can be used on individual judgement. The hypnotic drug has a minor...

  1. [Dutch College of General Practitioners' practice guideline on 'Vaginal bleeding'].

    Science.gov (United States)

    de Vries, Corlien J H; Meijer, Loes J; Janssen, C A H Ineke; Burgers, Jako S; Opstelten, Wim

    2015-01-01

    The revised Dutch College of General Practitioners' practice guideline on 'Vaginal bleeding' provides recommendations for abnormal bleeding in women in the reproduction phase of life and for post-menopausal bleeding. This guideline is closely attuned to the guideline on 'Heavy menstrual bleeding' of the Dutch Society of Obstetrics and Gynaecology. Transvaginal sonography is not reliable for excluding endometrial carcinoma in women with abnormal vaginal bleeding treated with tamoxifen. The choice of medical treatment is determined in consultation with the patient. The following factors are assessed: severity and bother, long-term need for contraception, preference for cycle control, desire to have a child, pain during menstruation, comorbidity and use of medication. Treatment options are nonhormonal (NSAIDs, or tranexamic acid) or hormonal (a levonorgestrel-releasing intrauterine system, or combined oral contraceptive). In women of reproductive age, referral is indicated if medical treatment is not effective. Other indications are intracavitary abnormalities diagnosed by transvaginal sonography, tamoxifen use, persistent contact bleeding, and suspicion of coagulation disorders. Indications for referral for post-menopausal bleeding include: sonographic endometrial thickness > 4 mm, abnormal cervical cytology, tamoxifen use, irregular bleeding during use of hormone therapy for vasomotor symptoms and persistent or recurrent bleeding, regardless of endometrial thickness.

  2. [Summary of the practice guideline 'Thyroid disorders' (first revision) from the Dutch College of General Practitioners

    NARCIS (Netherlands)

    Lieshout, J. van; Wessels, P.; Rijswijk, E. van; Boer, A.M; Wiersma, A.; Goudswaard, A.N.

    2007-01-01

    --The practice guideline 'Thyroid disorders' developed by the Dutch College of General Practitioners replaces the practice guideline 'Functional thyroid disorders' from 1996. Recommendations for palpable thyroid disorders have been added. --Hypothyroidism can often be treated by the general

  3. Video-assisted feedback in general practice internships using German general practitioner's guidelines.

    Science.gov (United States)

    Bölter, Regine; Freund, Tobias; Ledig, Thomas; Boll, Bernhard; Szecsenyi, Joachim; Roos, Marco

    2012-01-01

    The planned modification of the Medical Licenses Act in Germany will strengthen the specialty of general practice. Therefore, medical students should get to know the daily routine of general practitioners during their academic studies. At least 10% of students should get the possibility to spend one quarter of the internship, in the last year of their academic studies, in a practice of family medicine. The demonstrated teaching method aims at giving feedback to the student based on video recordings of patient consultations (student-patient) with the help of a checklist. Video-feedback is already successful used in medical teaching in Germany and abroad. This feasibility study aims at assessing the practicability of video-assisted feedback as a teaching method during internship in general practice. First of all, the general practice chooses a guideline as the learning objective. Secondly, a subsequent patient - student - consultation is recorded on video. Afterwards, a video-assisted formative feedback is given by the physician. A checklist with learning objectives (communication, medical examination, a structured case report according to the guideline) is used to structure the feedback content. The feasibility was assessed by a semi structured interview in order to gain insight into barriers and challenges for future implementation. The teaching method was performed in one general practice. Afterwards the teaching physician and the trainee intern were interviewed. The Following four main categories were identified: feasibility, performance, implementation in daily routine, challenges of the teaching concept.The results of the feasibility study show general practicability of this approach. Installing a video camera in one examination room may solve technical problems. The trainee intern mentioned theoretical and practical benefits using the guideline. The teaching physician noted the challenge to reflect on his daily routines in the light of evidence

  4. The generalized circular model

    NARCIS (Netherlands)

    Webers, H.M.

    1995-01-01

    In this paper we present a generalization of the circular model. In this model there are two concentric circular markets, which enables us to study two types of markets simultaneously. There are switching costs involved for moving from one circle to the other circle, which can also be thought of as

  5. Transport properties site descriptive model. Guidelines for evaluation and modelling

    International Nuclear Information System (INIS)

    Berglund, Sten; Selroos, Jan-Olof

    2004-04-01

    This report describes a strategy for the development of Transport Properties Site Descriptive Models within the SKB Site Investigation programme. Similar reports have been produced for the other disciplines in the site descriptive modelling (Geology, Hydrogeology, Hydrogeochemistry, Rock mechanics, Thermal properties, and Surface ecosystems). These reports are intended to guide the site descriptive modelling, but also to provide the authorities with an overview of modelling work that will be performed. The site descriptive modelling of transport properties is presented in this report and in the associated 'Strategy for the use of laboratory methods in the site investigations programme for the transport properties of the rock', which describes laboratory measurements and data evaluations. Specifically, the objectives of the present report are to: Present a description that gives an overview of the strategy for developing Site Descriptive Models, and which sets the transport modelling into this general context. Provide a structure for developing Transport Properties Site Descriptive Models that facilitates efficient modelling and comparisons between different sites. Provide guidelines on specific modelling issues where methodological consistency is judged to be of special importance, or where there is no general consensus on the modelling approach. The objectives of the site descriptive modelling process and the resulting Transport Properties Site Descriptive Models are to: Provide transport parameters for Safety Assessment. Describe the geoscientific basis for the transport model, including the qualitative and quantitative data that are of importance for the assessment of uncertainties and confidence in the transport description, and for the understanding of the processes at the sites. Provide transport parameters for use within other discipline-specific programmes. Contribute to the integrated evaluation of the investigated sites. The site descriptive modelling of

  6. General Quality Control (QC) Guidelines for SAM Methods

    Science.gov (United States)

    Learn more about quality control guidelines and recommendations for the analysis of samples using the methods listed in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

  7. Enhanced implementation of low back pain guidelines in general practice

    DEFF Research Database (Denmark)

    Riis, Allan; Jensen, Cathrine Elgaard; Bro, Flemming

    2013-01-01

    BACKGROUND: Evidence-based clinical practice guidelines may improve treatment quality, but the uptake of guideline recommendations is often incomplete and slow. Recently new low back pain guidelines are being launched in Denmark. The guidelines are considered to reduce personal and public costs...... and secondary outcomes pertain to the patient level. Assessments of outcomes are blinded and follow the intention-to-treat principle. Additionally, a process assessment will evaluate the degree to which the intervention elements will be delivered as planned, as well as measure changes in beliefs and behaviours...

  8. General fire protection guidelines for egyptian nuclear facilities. Vol. 4

    International Nuclear Information System (INIS)

    Radhad, S.; Hussien, A.Z.; Hammad, F.H.

    1996-01-01

    The purpose of this paper is to establish the regulatory requirements of that will provide and ensure fire protection of egyptian nuclear facilities. Those facilities that use, handle and store low and/or medium radioactive substances are included. Two or more classes of occupancy are considered to occur in the same building or structure. Fir protection measures and systems were reviewed for three of the egyptian Nuclear facilities. These are egypt first nuclear reactor (ETRR-1) building and systems, hot laboratories buildings and facilities, and the building including the AECL type Is-6500 industrial cobalt-60 gamma irradiator E gypt's mega gamma I . The study includes the outlines of the various aspects of fire protection with a view to define the relevant highlights and scope of egyptian guideline for nuclear installations. The study considers fire protection aspects including the following items: 1- Site selection. 2- General facility design. 3- Fire alarm, detection and suppression systems. 4- Protection for specific areas/control room, cable spreading room, computer room) 5- Fire emergency response planning. 6- Fire water supply. 7- Emergency lighting and communication. 8- Rescue and escape routes. 9- Explosion protection. 10-Manual fire fighting. 11- Security consideration in the interest of fire protection. 12- quality assurance programme. Therefore, first of all the design stage, then during the construction stage, and later during the operation stage, measures must be taken to forestall the risks associated with the outbreak of fire and to ensure that consequences of fire accidents remain limited

  9. General guidelines for recommendation of sites for nuclear waste repositories

    International Nuclear Information System (INIS)

    1983-01-01

    These guidelines were developed in accordance with the requirements of Section 112(a) of the Nuclear Waste Policy Act of 1982 for use by the Secretary of Energy in evaluating the suitability of sites for the development of repositories. The guidelines will be used for suitability evaluations and determinations made pursuant to Section 112(b) and any preliminary suitability determinations required by Section 114(f). The guidelines set forth in this Part are intended to complement the requirements set forth in the Act, 10 CFR Part 60, and 40 CFR Part 191. In applying these guidelines, the DOE will resolve any inconsistencies between these guidelines and the above documents in a manner determined by the DOE to most closely agree with the intent of the Act

  10. Ocean General Circulation Models

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jin-Ho; Ma, Po-Lun

    2012-09-30

    1. Definition of Subject The purpose of this text is to provide an introduction to aspects of oceanic general circulation models (OGCMs), an important component of Climate System or Earth System Model (ESM). The role of the ocean in ESMs is described in Chapter XX (EDITOR: PLEASE FIND THE COUPLED CLIMATE or EARTH SYSTEM MODELING CHAPTERS). The emerging need for understanding the Earth’s climate system and especially projecting its future evolution has encouraged scientists to explore the dynamical, physical, and biogeochemical processes in the ocean. Understanding the role of these processes in the climate system is an interesting and challenging scientific subject. For example, a research question how much extra heat or CO2 generated by anthropogenic activities can be stored in the deep ocean is not only scientifically interesting but also important in projecting future climate of the earth. Thus, OGCMs have been developed and applied to investigate the various oceanic processes and their role in the climate system.

  11. Strategy Guideline. Modeling Enclosure Design in Above-Grade Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J. [Building Science Corporation, Westford, MA (United States); Ueno, K. [Building Science Corporation, Westford, MA (United States); Musunuru, S. [Building Science Corporation, Westford, MA (United States)

    2016-02-01

    The Strategy Guideline, written by the U.S. Department of Energy's research team Building Science Corporation, 1) describes how to model and interpret results of models for above-grade walls, and 2) analyzes the failure thresholds and criteria for above-grade walls. A library of above-grade walls with historically successful performance was used to calibrate WUFI (Wärme und Feuchte instationär) software models. The information is generalized for application to a broad population of houses within the limits of existing experience.

  12. The general dynamic model

    DEFF Research Database (Denmark)

    Borregaard, Michael K.; Matthews, Thomas J.; Whittaker, Robert James

    2016-01-01

    Aim: Island biogeography focuses on understanding the processes that underlie a set of well-described patterns on islands, but it lacks a unified theoretical framework for integrating these processes. The recently proposed general dynamic model (GDM) of oceanic island biogeography offers a step...... towards this goal. Here, we present an analysis of causality within the GDM and investigate its potential for the further development of island biogeographical theory. Further, we extend the GDM to include subduction-based island arcs and continental fragment islands. Location: A conceptual analysis...... dynamics of distinct island types are predicted to lead to markedly different evolutionary dynamics. This sets the stage for a more predictive theory incorporating the processes governing temporal dynamics of species diversity on islands....

  13. [The Dutch College of General Practitioners practice guideline 'The menopause'; reaction of the field of general practice

    NARCIS (Netherlands)

    Bosch, W.J.H.M. van den

    2002-01-01

    The Dutch College of General Practitioners' practice guideline on the menopause will not be any major cause for discussion. The hot issue of giving oestrogens to peri- and postmenopausal women to prevent osteoporosis or cardiovascular disease was already covered in the practice guideline on

  14. Modeling Guidelines for Code Generation in the Railway Signaling Context

    Science.gov (United States)

    Ferrari, Alessio; Bacherini, Stefano; Fantechi, Alessandro; Zingoni, Niccolo

    2009-01-01

    recommendations has been performed for the automotive control systems domain in order to enforce code generation [7]. The MAAB guidelines have been found profitable also in the aerospace/avionics sector [1] and they have been adopted by the MathWorks Aerospace Leadership Council (MALC). General Electric Transportation Systems (GETS) is a well known railway signaling systems manufacturer leading in Automatic Train Protection (ATP) systems technology. Inside an effort of adopting formal methods within its own development process, GETS decided to introduce system modeling by means of the MathWorks tools [2], and in 2008 chose to move to code generation. This article reports the experience performed by GETS in developing its own modeling standard through customizing the MAAB rules for the railway signaling domain and shows the result of this experience with a successful product development story.

  15. Extraction and use of linguistic patterns for modelling medical guidelines

    NARCIS (Netherlands)

    Serban, Radu; ten Teije, Annette; van Harmelen, Frank; Marcos, Mar; Polo-Conde, Cristina

    Objective: The quality of knowledge updates in evidence-based medical guidelines can be improved and the effort spent for updating can be reduced if the knowledge underlying the guideline text is explicitly modelled using the so-called linguistic guideline patterns, mappings between a text fragment

  16. [The practice guideline 'Anemia' from the Dutch College of General Practitioners; a response from the perspective of general practice medicine

    NARCIS (Netherlands)

    Bosch, W.J.H.M. van den

    2003-01-01

    The practice guideline 'Anaemia' from the Dutch College of General Practitioners will certainly be a support for the Dutch general practitioner. The inclusion of an algorithm to make a more precise diagnosis is an experiment that needs to be evaluated in the near future. However, many general

  17. Authoring and verification of clinical guidelines: a model driven approach.

    Science.gov (United States)

    Pérez, Beatriz; Porres, Ivan

    2010-08-01

    The goal of this research is to provide a framework to enable authoring and verification of clinical guidelines. The framework is part of a larger research project aimed at improving the representation, quality and application of clinical guidelines in daily clinical practice. The verification process of a guideline is based on (1) model checking techniques to verify guidelines against semantic errors and inconsistencies in their definition, (2) combined with Model Driven Development (MDD) techniques, which enable us to automatically process manually created guideline specifications and temporal-logic statements to be checked and verified regarding these specifications, making the verification process faster and cost-effective. Particularly, we use UML statecharts to represent the dynamics of guidelines and, based on this manually defined guideline specifications, we use a MDD-based tool chain to automatically process them to generate the input model of a model checker. The model checker takes the resulted model together with the specific guideline requirements, and verifies whether the guideline fulfils such properties. The overall framework has been implemented as an Eclipse plug-in named GBDSSGenerator which, particularly, starting from the UML statechart representing a guideline, allows the verification of the guideline against specific requirements. Additionally, we have established a pattern-based approach for defining commonly occurring types of requirements in guidelines. We have successfully validated our overall approach by verifying properties in different clinical guidelines resulting in the detection of some inconsistencies in their definition. The proposed framework allows (1) the authoring and (2) the verification of clinical guidelines against specific requirements defined based on a set of property specification patterns, enabling non-experts to easily write formal specifications and thus easing the verification process. Copyright 2010 Elsevier Inc

  18. American Association for Dental Schools Curricular Guidelines for Microscopic Anatomy (General and Oral).

    Science.gov (United States)

    Susi, Frank; Mundell, Robert

    1980-01-01

    Guidelines developed by the Section on Anatomical Sciences of the American Association for Dental Schools are presented. These guidelines were drawn up as an effort to provide a general criterion-referenced standard against which a school can measure its course content in histology. (MLW)

  19. Glauber model and its generalizations

    International Nuclear Information System (INIS)

    Bialkowski, G.

    The physical aspects of the Glauber model problems are studied: potential model, profile function and Feynman diagrams approaches. Different generalizations of the Glauber model are discussed: particularly higher and lower energy processes and large angles [fr

  20. Generalized instrumental variable models

    OpenAIRE

    Andrew Chesher; Adam Rosen

    2014-01-01

    This paper develops characterizations of identified sets of structures and structural features for complete and incomplete models involving continuous or discrete variables. Multiple values of unobserved variables can be associated with particular combinations of observed variables. This can arise when there are multiple sources of heterogeneity, censored or discrete endogenous variables, or inequality restrictions on functions of observed and unobserved variables. The models g...

  1. Implementation of the Dutch low back pain guideline for general practitioners: a cluster randomized controlled trial

    NARCIS (Netherlands)

    Engers, AJ; Wensing, M.; van Tulder, M.; Timmermans, A.; Oostendorp, R.A.B.; Koes, B.W.; Grol, R.P.T.M.

    2005-01-01

    STUDY DESIGN.: Cluster randomized controlled trial for a multifaceted implementation strategy. OBJECTIVES.: To assess the effectiveness of tailored interventions (multifaceted implementation strategy) to implement the Dutch low back pain guideline for general practitioners with regard to adherence

  2. Implementation of the Dutch low back pain guideline for general practitioners: a cluster randomized controlled trial.

    NARCIS (Netherlands)

    Engers, A.J.; Wensing, M.J.P.; Tulder, M.W. van; Timmermans, A.; Oostendorp, R.A.B.; Koes, B.W.; Grol, R.P.T.M.

    2005-01-01

    STUDY DESIGN: Cluster randomized controlled trial for a multifaceted implementation strategy. OBJECTIVES: To assess the effectiveness of tailored interventions (multifaceted implementation strategy) to implement the Dutch low back pain guideline for general practitioners with regard to adherence to

  3. 75 FR 22631 - Notice of Continuance for General Clearance for Guidelines, Applications, and Reporting Forms

    Science.gov (United States)

    2010-04-29

    ... NATIONAL FOUNDATION FOR THE ARTS AND HUMANITIES Notice of Continuance for General Clearance for Guidelines, Applications, and Reporting Forms AGENCY: Institute of Museum and Library Services. ACTION... of higher education, library and museum professional associations, and museum and library...

  4. [The practice guideline 'Smoking cessation' from the Dutch College of General Practitioners; a response from the perspective of general practice

    NARCIS (Netherlands)

    Weel, C. van

    2008-01-01

    This article reviews the practice guideline from the Dutch College of General Practitioners on smoking cessation. General practitioners (GP) should strive after smoking cessation when patients consult and ask for support to stop smoking. Moreover, the practitioner should also show such initiative

  5. EFSUMB Guidelines on Interventional Ultrasound (INVUS), Part I. General Aspects (long Version)

    DEFF Research Database (Denmark)

    Lorentzen, T; Nolsøe, C P; Ewertsen, C

    2015-01-01

    This is the first part of the Guidelines on Interventional Ultrasound of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) and covers all general aspects of ultrasound-guided procedures (long version).......This is the first part of the Guidelines on Interventional Ultrasound of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) and covers all general aspects of ultrasound-guided procedures (long version)....

  6. 43 CFR 4.100 - General rules and guidelines.

    Science.gov (United States)

    2010-10-01

    ... APPEALS PROCEDURES Special Rules of Practice Before the Interior Board of Contract Appeals § 4.100 General... Contract Appeals. (2) Special applicability. The rule set forth in § 4.102(a) provides for alternative..., Public Law 95-563 (41 U.S.C. 601-613). The rules set forth in §§ 4.102 (c), (d), and (e), 4.113, and 4...

  7. ASVCP quality assurance guidelines: control of general analytical factors in veterinary laboratories.

    Science.gov (United States)

    Flatland, Bente; Freeman, Kathy P; Friedrichs, Kristen R; Vap, Linda M; Getzy, Karen M; Evans, Ellen W; Harr, Kendal E

    2010-09-01

    Owing to lack of governmental regulation of veterinary laboratory performance, veterinarians ideally should demonstrate a commitment to self-monitoring and regulation of laboratory performance from within the profession. In response to member concerns about quality management in veterinary laboratories, the American Society for Veterinary Clinical Pathology (ASVCP) formed a Quality Assurance and Laboratory Standards (QAS) committee in 1996. This committee recently published updated and peer-reviewed Quality Assurance Guidelines on the ASVCP website. The Quality Assurance Guidelines are intended for use by veterinary diagnostic laboratories and veterinary research laboratories that are not covered by the US Food and Drug Administration Good Laboratory Practice standards (Code of Federal Regulations Title 21, Chapter 58). The guidelines have been divided into 3 reports on 1) general analytic factors for veterinary laboratory performance and comparisons, 2) hematology and hemostasis, and 3) clinical chemistry, endocrine assessment, and urinalysis. This report documents recommendations for control of general analytical factors within veterinary clinical laboratories and is based on section 2.1 (Analytical Factors Important In Veterinary Clinical Pathology, General) of the newly revised ASVCP QAS Guidelines. These guidelines are not intended to be all-inclusive; rather, they provide minimum guidelines for quality assurance and quality control for veterinary laboratory testing. It is hoped that these guidelines will provide a basis for laboratories to assess their current practices, determine areas for improvement, and guide continuing professional development and education efforts. ©2010 American Society for Veterinary Clinical Pathology.

  8. Generalized, Linear, and Mixed Models

    CERN Document Server

    McCulloch, Charles E; Neuhaus, John M

    2011-01-01

    An accessible and self-contained introduction to statistical models-now in a modernized new editionGeneralized, Linear, and Mixed Models, Second Edition provides an up-to-date treatment of the essential techniques for developing and applying a wide variety of statistical models. The book presents thorough and unified coverage of the theory behind generalized, linear, and mixed models and highlights their similarities and differences in various construction, application, and computational aspects.A clear introduction to the basic ideas of fixed effects models, random effects models, and mixed m

  9. The general NFP hospital model.

    Science.gov (United States)

    Al-Amin, Mona

    2012-01-01

    Throughout the past 30 years, there has been a lot of controversy surrounding the proliferation of new forms of health care delivery organizations that challenge and compete with general NFP community hospitals. Traditionally, the health care system in the United States has been dominated by general NFP (NFP) voluntary hospitals. With the number of for-profit general hospitals, physician-owned specialty hospitals, and ambulatory surgical centers increasing, a question arises: “Why is the general NFP community hospital the dominant model?” In order to address this question, this paper reexamines the history of the hospital industry. By understanding how the “general NFP hospital” model emerged and dominated, we attempt to explain the current dominance of general NFP hospitals in the ever changing hospital industry in the United States.

  10. Introduction to generalized linear models

    CERN Document Server

    Dobson, Annette J

    2008-01-01

    Introduction Background Scope Notation Distributions Related to the Normal Distribution Quadratic Forms Estimation Model Fitting Introduction Examples Some Principles of Statistical Modeling Notation and Coding for Explanatory Variables Exponential Family and Generalized Linear Models Introduction Exponential Family of Distributions Properties of Distributions in the Exponential Family Generalized Linear Models Examples Estimation Introduction Example: Failure Times for Pressure Vessels Maximum Likelihood Estimation Poisson Regression Example Inference Introduction Sampling Distribution for Score Statistics Taylor Series Approximations Sampling Distribution for MLEs Log-Likelihood Ratio Statistic Sampling Distribution for the Deviance Hypothesis Testing Normal Linear Models Introduction Basic Results Multiple Linear Regression Analysis of Variance Analysis of Covariance General Linear Models Binary Variables and Logistic Regression Probability Distributions ...

  11. Antibiotics for acute respiratory infections in general practice: comparison of prescribing rates with guideline recommendations.

    Science.gov (United States)

    McCullough, Amanda R; Pollack, Allan J; Plejdrup Hansen, Malene; Glasziou, Paul P; Looke, David Fm; Britt, Helena C; Del Mar, Christopher B

    2017-07-17

    To compare the current rate of antibiotic prescribing for acute respiratory infections (ARIs) in Australian general practice with the recommendations in the most widely consulted therapeutic guidelines in Australia (Therapeutic Guidelines). Comparison of general practice activity data for April 2010 - March 2015 (derived from Bettering the Evaluation and Care of Health [BEACH] study) with estimated rates of prescribing recommended by Therapeutic Guidelines. Antibiotic prescribing rates and estimated guideline-recommended rates per 100 encounters and per full-time equivalent (FTE) GP per year for eight ARIs; number of prescriptions nationally per year. An estimated mean 5.97 million (95% CI, 5.69-6.24 million) ARI cases per year were managed in Australian general practice with at least one antibiotic, equivalent to an estimated 230 cases per FTE GP/year (95% CI, 219-240 cases/FTE/year). Antibiotics are not recommended by the guidelines for acute bronchitis/bronchiolitis (current prescribing rate, 85%) or influenza (11%); they are always recommended for community-acquired pneumonia (current prescribing rate, 72%) and pertussis (71%); and they are recommended for 0.5-8% of cases of acute rhinosinusitis (current prescribing rate, 41%), 20-31% of cases of acute otitis media (89%), and 19-40% cases of acute pharyngitis or tonsillitis (94%). Had GPs adhered to the guidelines, they would have prescribed antibiotics for 0.65-1.36 million ARIs per year nationally, or at 11-23% of the current prescribing rate. Antibiotics were prescribed more frequently than recommended for acute rhinosinusitis, acute bronchitis/bronchiolitis, acute otitis media, and acute pharyngitis/tonsillitis. Antibiotics are prescribed for ARIs at rates 4-9 times as high as those recommended by Therapeutic Guidelines. Our data provide the basis for setting absolute targets for reducing antibiotic prescribing in Australian general practice.

  12. EFSUMB Guidelines on Interventional Ultrasound (INVUS), Part I. General Aspects (Short Version)

    DEFF Research Database (Denmark)

    Lorentzen, T.; Nolsøe, C P; Ewertsen, C

    2015-01-01

    This is the first part of the Guidelines on Interventional Ultrasound of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) and covers all general aspects of ultrasound-guided procedures (short version; the long version is published online).......This is the first part of the Guidelines on Interventional Ultrasound of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) and covers all general aspects of ultrasound-guided procedures (short version; the long version is published online)....

  13. Embedding the guideline elements model in web ontology language.

    Science.gov (United States)

    Tran, Nam; Michel, George; Krauthammer, Michael; Shiffman, Richard N

    2009-11-14

    The Guideline Elements Model (GEM) uses XML to represent the heterogeneous knowledge contained in clinical practice guidelines. GEM has important applications in computer aided guideline authoring and clinical decision support systems. However, its XML representation format could limit its potential impact, as semantic web ontology languages, such as OWL, are becoming major knowledge representation frameworks in medical informatics. In this work, we present a faithful translation of GEM from XML into OWL. This translation is intended to keep the knowledge model of GEM intact, as this knowledge model has been carefully designed and has become a recognized standard. An OWL representation would make GEM more applicable in medical informatics systems that rely on semantic web. This work will also be the initial step in making GEM a guideline recommendation ontology.

  14. On the general ontological foundations of conceptual modeling

    NARCIS (Netherlands)

    Guizzardi, G.; Herre, Heinrich; Wagner, Gerd; Spaccapietra, Stefano; March, Salvatore T.; Kambayashi, Yahiko

    2002-01-01

    As pointed out in the pioneering work of [WSW99,EW01], an upper level ontology allows to evaluate the ontological correctness of a conceptual model and to develop guidelines how the constructs of a conceptual modeling language should be used. In this paper we adopt the General Ontological Language

  15. Doctors as patients: postal survey examining consultants and general practitioners adherence to guidelines.

    Science.gov (United States)

    Forsythe, M; Calnan, M; Wall, B

    1999-09-04

    To examine the adherence by senior NHS medical staff to the BMA guidelines on the ethical responsibilities of doctors towards themselves and their families. Postal semistructured questionnaire. Four randomly selected NHS trusts and three local medical committees in South Thames region. Consultants and principals in general practice. Personal use of health services. The response rate was 64% (724) for general practitioners and 72% (427) for consultants after three mailings. Most (1106, 96%) respondents were registered with a general practitioner, although little use was made of their services. 159 (26%) general practitioners were registered with a general practitioner in their own practice and 80 (11%) admitted to looking after members of their family. 73 (24%) consultants would never see their general practitioner before obtaining consultant advice. Most consultants and general practitioners admitted to prescribing for themselves and their family. Responses to vignettes for different health problems indicated a general reluctance to take time off, but there were differences between consultants and general practitioners and by sex. Views on improvements needed included the possibility of a "doctor's doctor," access to out of area secondary care, an occupational health service for general practitioners, and regular health check ups. The guidelines are largely not being followed, perhaps because of the difficulties of obtaining access to general practitioners outside working hours. The occupational health service should be expanded and a general practitioner service for NHS staff piloted.

  16. [Summary of the 'Thyroid disorders' guideline of the Dutch College of General Practitioners' (NHG)

    NARCIS (Netherlands)

    Sijbom, M.; Lieshout, J. van; Felix-Schollaart, B.; Burgers, J.S.; Bouma, M.

    2013-01-01

    - The 'Thyroid disorders' guideline of the Dutch College of General Practitioners (NHG) provides recommendations for the diagnosis and management of hypothyroidism, hyperthyroidism and changes in the size of the thyroid gland, such as goitre and thyroid nodules. - Hypothyroid patients younger than

  17. Ground-water transport model selection and evaluation guidelines

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1983-01-01

    Guidelines are being developed to assist potential users with selecting appropriate computer codes for ground-water contaminant transport modeling. The guidelines are meant to assist managers with selecting appropriate predictive models for evaluating either arid or humid low-level radioactive waste burial sites. Evaluation test cases in the form of analytical solutions to fundamental equations and experimental data sets have been identified and recommended to ensure adequate code selection, based on accurate simulation of relevant physical processes. The recommended evaluation procedures will consider certain technical issues related to the present limitations in transport modeling capabilities. A code-selection plan will depend on identifying problem objectives, determining the extent of collectible site-specific data, and developing a site-specific conceptual model for the involved hydrology. Code selection will be predicated on steps for developing an appropriate systems model. This paper will review the progress in developing those guidelines. 12 references

  18. General guidelines for the assessment of internal dose from monitoring data: Progress of the IDEAS project

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Bailey, M.; Blanchardon, E.; Cruz-Suarez, R.; Berkovski, V.; Castellani, C. M.; Hurtgenv, C.; Leguen, B.; Malatova, I.; Marsh, J.; Stather, J.; Zeger, J.

    2007-01-01

    In recent major international intercomparison exercises on intake and internal dose assessments from monitoring data, the results calculated by different participants varied significantly. Based on this experience the need for harmonisation of the procedures has been formulated within an EU 5. Framework Programme research project. The aim of the project, IDEAS, is to develop general guidelines for standardising assessments of intakes and internal doses. The IDEAS project started in October 2001 and ended in June 2005. The project is closely related to some goals of the work of Committee 2 of the ICRP and since 2003 there has been close cooperation between the two groups. To ensure that the guidelines are applicable to a wide range of practical situations, the first step was to compile a database of well-documented cases of internal contamination. In parallel, an improved version of an existing software package was developed and distributed to the partners for further use. A large number of cases from the database was evaluated independently by the partners and the results reviewed. Based on these evaluations, guidelines were drafted and discussed with dosimetry professionals from around the world by means of a virtual workshop on the Internet early in 2004. The guidelines have been revised and refined on the basis of the experiences and discussions in this virtual workshop. The general philosophy of the Guidelines is presented here, focusing on the principles of harmonisation, optimisation and proportionality. Finally, the proposed Levels of Task to structure the approach of internal dose evaluation are reported. (authors)

  19. Best-practices guidelines for L2PSA development and applications. Volume 1 - General

    International Nuclear Information System (INIS)

    Raimond, E.; Pichereau, F.; Durin, T.; Rahni, N.; Loeffler, H.; Roesch, O.; Lajtha, G.; Santamaria, C.S.; Dienstbier, J.; Rydl, A.; Holmberg, J.E.; Lindholm, I.; Maennistoe, I.; Pauli, E.M.; Dirksen, G.; Grindon, L.; Peers, K.; Bassi, C.; Hulqvist, G.; Parozzi, F.; Polidoro, F.; Cazzoli, E.; Vitazkova, J.; Burgazzi, L.; Brinkman, H.; Seidel, A.; Schubert, B.; Wohlstein, R.; Guentay, S.; Oury, L.; Ngatchou, C.; Siltanen, S.; Niemela, I.; Routamo, T.; Vincon, L.; Helstroem, P.

    2010-01-01

    The objective of this coordinated action was to develop best practice guidelines for the performance and application of Level 2 PSA with a view to achieve harmonisation at EU level and to allow a meaningful and practical uncertainty evaluation in a Level 2 PSA. Specific relationships with communities in charge of nuclear reactor safety (utilities, safety authorities, vendors, and research or services companies) have been established in order to define the current needs in terms of guidelines for Level 2 PSA development and application. An international workshop was organised in Hamburg, with the support of VATTENFALL, in November 2008. The Level 2 PSA experts from ASAMPSA2 project partners have proposed some guidelines for the development and application of L2PSA based on their experience, open literature, and on information available from international cooperation (EC Severe Accident network of Excellence - SARNET, IAEA standards, OECD-NEA publications and workshop). There are a large number of technical issues addressed in the guideline which are not all covered with the same level of detail in the first version of the guideline. This version was submitted for external review in November 2010 by severe accident and PSA experts (especially from SARNET and OECD-NEA members). The feedback of the external review will be dis cussed during an international open works hop planned for March 2011 and all outcomes will be taken into consideration in the final version of this guideline (June 2011). The guideline includes 3 volumes: - Volume 1 - General considerations on L2PSA. - Volume 2 - Technical recommendations for Gen II and III reactors. - Volume 3 - Specific considerations for future reactors (Gen IV). The recommendations formulated in the guideline should not be considered as 'mandatory' but should help Level 2 PSA developers to achieve high quality studies with limited time and resources. It may also help Level 2 PSA reviewers by positioning one specific

  20. Multivariate covariance generalized linear models

    DEFF Research Database (Denmark)

    Bonat, W. H.; Jørgensen, Bent

    2016-01-01

    We propose a general framework for non-normal multivariate data analysis called multivariate covariance generalized linear models, designed to handle multivariate response variables, along with a wide range of temporal and spatial correlation structures defined in terms of a covariance link...... function combined with a matrix linear predictor involving known matrices. The method is motivated by three data examples that are not easily handled by existing methods. The first example concerns multivariate count data, the second involves response variables of mixed types, combined with repeated...... measures and longitudinal structures, and the third involves a spatiotemporal analysis of rainfall data. The models take non-normality into account in the conventional way by means of a variance function, and the mean structure is modelled by means of a link function and a linear predictor. The models...

  1. Cosmological models in general relativity

    Indian Academy of Sciences (India)

    Cosmological models in general relativity. B B PAUL. Department of Physics, Nowgong College, Nagaon, Assam, India. MS received 4 October 2002; revised 6 March 2003; accepted 21 May 2003. Abstract. LRS Bianchi type-I space-time filled with perfect fluid is considered here with deceler- ation parameter as variable.

  2. Video-assisted feedback in general practice internships using German general practitioner's guidelines

    NARCIS (Netherlands)

    Bolter, R.; Freund, T.; Ledig, T.; Boll, B.; Szecsenyi, J.; Roos, M.

    2012-01-01

    Introduction: The planned modification of the Medical Licenses Act in Germany will strengthen the specialty of general practice. Therefore, medical students should get to know the daily routine of general practitioners during their academic studies. At least 10% of students should get the

  3. Parameterization guidelines and considerations for hydrologic models

    Science.gov (United States)

     R. W. Malone; G. Yagow; C. Baffaut; M.W  Gitau; Z. Qi; Devendra Amatya; P.B.   Parajuli; J.V. Bonta; T.R.  Green

    2015-01-01

     Imparting knowledge of the physical processes of a system to a model and determining a set of parameter values for a hydrologic or water quality model application (i.e., parameterization) are important and difficult tasks. An exponential...

  4. Impact of triage guidelines on prehospital triage: comparison of guidelines with a statistical model.

    Science.gov (United States)

    Parikh, Priti P; Parikh, Pratik; Guthrie, Bradley; Mamer, Logan; Whitmill, Melissa; Erskine, Timothy; Woods, Randy; Saxe, Jonathan

    2017-12-01

    The American College of Surgeons developed the National Field Triage Decision Scheme (NFTDS) that has been adapted by many trauma centers in the nation, but quantitative evidence of its efficacy is unclear. We compare the NFTDS and state of Ohio guidelines to the "observed" rates and with rates derived using a statistical model. We used 4757 trauma records from 2008-2012 available from the state and calculated undertriage (UT) and overtriage (OT) rates. We then simulated the NFTDS and the state guidelines for those years and estimated the corresponding UT and OT rates. We finally compared these rates with those derived from a multivariate logistic regression model. For the state data, both NFTDS and state guidelines produced lower UT rate (∼9%) compared with the observed rate (∼17%), whereas the OT rates were higher (>85%) than the observed rates (∼54%). The statistical model identified novel factors that were not directly available in the NFTDS; change in responsiveness (odds ratio [OR] = 1.924) and complaint in body (OR = 3.140), back (OR = 1.890), chest (OR = 3.191), head (OR = 3.878), and abdomen (OR = 2.966). Although the statistical model performed similar to observed rates, it performed considerably better than NFTDS (UT = 1.93% versus 9.03%; OT = 66.42% versus 87.52%) and state guidelines (UT = 2.18% versus 8.72%; OT = 64.09% versus 86.52%). The current NFTDS and state's triage guidelines do not appear to achieve the ACS recommendation of <5% UT and <35% OT rates in the state of Ohio. Inclusion of region-specific factors may help enhance the current NFTDS guidelines and aid in the first impression or judgment of the Emergency Medical Services personnel to improve trauma care and reduce cost. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Developing a computer delivered, theory based intervention for guideline implementation in general practice

    Directory of Open Access Journals (Sweden)

    Ashworth Mark

    2010-11-01

    Full Text Available Abstract Background Non-adherence to clinical guidelines has been identified as a consistent finding in general practice. The purpose of this study was to develop theory-informed, computer-delivered interventions to promote the implementation of guidelines in general practice. Specifically, our aim was to develop computer-delivered prompts to promote guideline adherence for antibiotic prescribing in respiratory tract infections (RTIs, and adherence to recommendations for secondary stroke prevention. Methods A qualitative design was used involving 33 face-to-face interviews with general practitioners (GPs. The prompts used in the interventions were initially developed using aspects of social cognitive theory, drawing on nationally recommended standards for clinical content. The prompts were then presented to GPs during interviews, and iteratively modified and refined based on interview feedback. Inductive thematic analysis was employed to identify responses to the prompts and factors involved in the decision to use them. Results GPs reported being more likely to use the prompts if they were perceived as offering support and choice, but less likely to use them if they were perceived as being a method of enforcement. Attitudes towards using the prompts were also related to anticipated patient outcomes, individual prescriber differences, accessibility and presentation of prompts and acceptability of guidelines. Comments on the prompts were largely positive after modifying them based on participant feedback. Conclusions Acceptability and satisfaction with computer-delivered prompts to follow guidelines may be increased by working with practitioners to ensure that the prompts will be perceived as valuable tools that can support GPs' practice.

  6. Developing a CAI Graphics Simulation Model: Guidelines.

    Science.gov (United States)

    Strickland, R. Mack; Poe, Stephen E.

    1989-01-01

    Discusses producing effective instructional software using a balance of course content and technological capabilities. Describes six phases of an instructional development model: discovery, design, development, coding, documentation, and delivery. Notes that good instructional design should have learner/computer interaction, sequencing of…

  7. ORGEST: Regional guidelines and silvicultural models for sustainable forest management

    Energy Technology Data Exchange (ETDEWEB)

    Piqué, Míriam; Vericat, Pau; Beltrán, Mario

    2017-11-01

    Aim of the study: To develop regional guidelines for sustainable forest management. Area of the study: Forests of Catalonia (NE Spain). Material and methods: The process of developing the forest management guidelines (FMG) started by establishing a thorough classification of forest types at stand level. This classification hinges on two attributes: tree species composition and site quality based on ecological variables, which together determine potential productivity. From there, the management guidelines establish certain objectives and silvicultural models for each forest type. The forest type classifications, like the silvicultural models, were produced using both existing and newly-built growth models based on data from the National Forest Inventory (NFI) and expert knowledge. The effort involved over 20 expert working groups in order to better integrate the expertise and vision of different sectorial agents. Main results: The FMG consist in quantitative silvicultural models that include typical silvicultural variables, technical descriptions of treatments and codes of good practice. Guidelines now cover almost all forest types in Catalonia (spanning up to 90% of the Catalan forest area). Different silvicultural models have been developed for pure and mixed stands, different site quality classes (2–3 classes per species), and even- and multi-aged stands. Research highlights: FMG: i) orient the management of private and public forests, (ii) provide a technical scaffold for efficient allocation/investment of public subsidies in forest management, and (iii) bridge forest planning instruments at regional (strategic-tactical) and stand (operational) level.

  8. Modeling pediatric vaccination guidelines in a data warehouse.

    Science.gov (United States)

    Housman, Daniel; Greim, Julie; Morgan, Stephen J; Nelson, Sarah M; Flanagan, Tara; Martin, Kerry; Eskin, Michael; Einbinder, Jonathan S

    2008-11-06

    Frequent updates and complexity of vaccination schedules can make it difficult for pediatric practices to ensure adherence to immunization guidelines. To address this problem, Partners HealthCare System (PHS) has created a quality reporting utility to manage pediatric immunizations and to support quality improvement initiatives. The rules-based solution uses reference database tables to model the logic for each vaccine.

  9. Fermions as generalized Ising models

    Directory of Open Access Journals (Sweden)

    C. Wetterich

    2017-04-01

    Full Text Available We establish a general map between Grassmann functionals for fermions and probability or weight distributions for Ising spins. The equivalence between the two formulations is based on identical transfer matrices and expectation values of products of observables. The map preserves locality properties and can be realized for arbitrary dimensions. We present a simple example where a quantum field theory for free massless Dirac fermions in two-dimensional Minkowski space is represented by an asymmetric Ising model on a euclidean square lattice.

  10. Assessing biocomputational modelling in transforming clinical guidelines for osteoporosis management.

    Science.gov (United States)

    Thiel, Rainer; Viceconti, Marco; Stroetmann, Karl

    2011-01-01

    Biocomputational modelling as developed by the European Virtual Physiological Human (VPH) Initiative is the area of ICT most likely to revolutionise in the longer term the practice of medicine. Using the example of osteoporosis management, a socio-economic assessment framework is presented that captures how the transformation of clinical guidelines through VPH models can be evaluated. Applied to the Osteoporotic Virtual Physiological Human Project, a consequent benefit-cost analysis delivers promising results, both methodologically and substantially.

  11. The ARGA study with Italian general practitioners: prescriptions for allergic rhinitis and adherence to ARIA guidelines.

    Science.gov (United States)

    Maio, S; Simoni, M; Baldacci, S; Angino, A; Martini, F; Cerrai, S; Sarno, G; Silvi, P; Borbotti, M; Pala, A P; Bresciani, M; Paggiaro, P L; Viegi, G

    2012-10-01

    General practitioners (GPs) are the healthcare professionals to whom patients with rhinitis firstly refer for their symptoms. In the present study, we assessed drug prescriptions for allergic rhinitis (AR) and evaluated prescriptive adherence to ARIA treatment guidelines. Data on 1379 AR patients were collected by 107 Italian GPs. Adherence to ARIA guidelines was evaluated according to AR severity classification. AR was diagnosed by GPs as mild intermittent for 46.2% of patients, mild persistent for 26.6%, moderate-severe intermittent for 20.2%, and moderate-severe persistent for 7%; 43.7% of AR patients had concomitant asthma. The most frequently prescribed therapeutic groups were antihistamines (anti-H, 76%) and nasal corticosteroids (NCS, 46%). Anti-H were significantly used more often to treat AR alone than AR + asthma (85 vs. 68%, p < 0.001), whereas NCS were used more often to treat AR + asthma than AR alone (50 vs. 42%, p = 0.01). Among patients with only mild intermittent AR, 39% were prescribed combined therapy. Among patients with moderate-severe persistent AR, 30% of those with AR alone and 18% of those with AR + asthma were prescribed monotherapy based on anti-H. GPs were more compliant with ARIA guidelines while treating AR alone (57%) than AR + asthma (46%) patients. The adherence increased according to the severity grade and was satisfactory for moderate-severe persistent AR (89% for AR alone and 95% for AR + asthma). Adherence to ARIA guidelines is satisfactory only for treatment of more severe patients, thus GPs often tend to treat patients independently from ARIA guidelines. Since prescription data only provide limited information to judge prescribing quality, some deviation from the gold standard are to be expected.

  12. [Summary of the practice guideline 'Vaginal discharge' (first revision) from the Dutch College of General Practitioners].

    Science.gov (United States)

    Boukes, F S; Boeke, A J P; Dekker, J H; Wiersma, T; Goudswaard, A N

    2007-06-16

    The 1996 practice guideline of the Dutch College of General Practitioners (NHG) on vaginal discharge has been updated. Most women who visit their doctor with complaints about vaginal discharge do not have an increased risk of a sexually-transmitted disease. Investigations into vaginal discharge comprise history taking, physical examination and microscopic analysis in the laboratory of the general practitioner. Additional investigation into Chlamydia, gonorrhoea and Trichomonas infection is only necessary if the patient history reveals an increased risk of a sexually-transmitted disease. A Candida infection or bacterial vaginosis should only be treated if the patient experiences bothersome complaints. Treatment of a Candida infection consists of a vaginally applied imidazole compound. Bacterial vaginosis can be treated with oral administration of metronidazole. Patients with vaginal fluor can be examined and, if necessary, treated by their general practitioner. Referral to a gynaecologist is rarely necessary.

  13. Chapter A6. Section 6.0. General Information and Guidelines

    Science.gov (United States)

    Wilde, Franceska D.; Radtke, Dean B.

    2005-01-01

    This report summarizes information, guidelines, and minimum requirements that apply generally to the seven field-measurement sections that comprise the rest of Chapter A6 of this U.S. Geological Survey (USGS) National Field Manual for the Collection of Water-Quality Data (NFM). Protocols are specified for establishing and maintaining data records, use of field-measurement instruments and methods, and quality assurance of data-collection and reporting methods that are relevant to surface-water and ground-water field-measurement activities.

  14. nestor Guideline for Preservation Planning – a Process Model

    Directory of Open Access Journals (Sweden)

    Sabine Schrimpf

    2014-02-01

    Full Text Available The nestor guideline for preservation planning is the latest in a series of nestor publications. nestor is the German competence network for digital preservation and it offers all interested parties from the private and public domains the possibility to participate in working groups. The guideline for preservation planning is the result of such a working group, which discussed the conceptual and practical issues of implementing the OAIS Functional Entity “Preservation Planning”.The guideline describes a process model and offers some guidance on potential implementations. It integrates and builds on recognized community concepts like Significant Properties, the OAIS Designated Community, the National Archives of Australia’s Performance Model, the PREMIS concept of Intellectual Entities and Representations, and the PLANET’s approach to preservation planning. Furthermore, it introduces the concepts “intended use” (Nutzungsziele, “information type” (Informationstyp and “preservation group” (Erhaltungsgruppe. The purpose of these new categories is that information objects shall be grouped by information type (e.g., audio, video, text… and intended use (e.g., reading for pleasure, search for specific information… to preservation groups for automatic processing. Significant properties can then be derived for whole preservation groups. The file format alone is considered as not completely sufficient for such categorisation. Some exemplary implementation solutions of the new concepts are presented in an annex.The guideline takes into account that resources for preservation planning and preservation actions are limited and has therefore adopted 4 premises: adequacy, financial viability, automation, and authenticity of archived objects. Its pragmatic approach becomes apparent in the definition and explanation of these dimensions. The guideline is written from the point of view of representatives of memory institutions, i

  15. [Do general practitioners follow the national guidelines for treating urinary tract infections with antibiotics?].

    Science.gov (United States)

    Agdestein, Benedicte; Lindbæk, Morten; Gjelstad, Svein

    2011-09-06

    Incorrect use of antibiotics is a major public health concern both nationally and globally due to the development of antibiotic resistance. The goal of this study was to see if prescription of antibiotics for urinary tract infections in general practice was in accordance with national guidelines. We combined two sets of data from February and March 2003: prescriptions of antibiotics redeemed in pharmacies, and electronic billing cards collected from the National Insurance Agency from 145 general practitioners in Vestfold county. We analysed all consultations related to urinary tract problems, and we found which antibiotics had been prescribed and for how long. The treatment was then compared with the national guidelines. A logistic regression analysis identified factors associated with adequate treatment length. Trimetoprime and mecillinam were most frequently prescribed to both genders. Sixty-nine (6 %) of the total 1,102 prescriptions were quinolones. A total of 271 (32 %) of 847 patients who were prescribed antibiotics for cystitis did not get treatment of sufficient length. Female and young patients were more often given the correct duration of treatment. Doctors with 1,000-1,500 patients more frequently prescribed sufficiently long treatment compared to other physicians. Six patients (0.5 %) were prescribed another antibiotic between two and 14 days after the first prescription. The choice of antibiotics conformed well with national guidelines, but the duration of the treatment was often too short. In spite of this, only 0.5 % showed signs of relapse. A number of factors associated with adequate treatment length were identified. The empirical use of furadantin can be increased.

  16. Ontology-driven extraction of linguistic patterns for modelling clinical guidelines

    NARCIS (Netherlands)

    Serban, Radu; Teije, Annette Ten; Van Harmelen, Frank; Marcos, Mar; Polo-Conde, Cristina

    2005-01-01

    Evidence-based clinical guidelines require frequent updates duo to research and technology advances. The quality of guideline updates can be improved if the knowledge underlying the guideline text is explicitly modelled using the so-called guideline patterns (GPs), mappings between a text fragment

  17. A multifaceted implementation strategy versus passive implementation of low back pain guidelines in general practice

    DEFF Research Database (Denmark)

    Riis, Allan; Jensen, Cathrine Elgaard; Bro, Flemming

    2016-01-01

    primary care to secondary care. The primary aim of this project was to reduce secondary care referral within 12 weeks by a multifaceted implementation strategy (MuIS). METHODS: In a cluster randomised design, 189 general practices from the North Denmark Region were invited to participate. Practices were...... randomised (1:1) and stratified by practice size to MuIS (28 practices) or a passive implementation strategy (PaIS; 32 practices). Included were patients with LBP aged 18 to 65 years who were able to complete questionnaires, had no serious underlying pathology, and were not pregnant. We developed a Mu.......31 to 0.81; p = 0.004]). CONCLUSIONS: Using a MuIS changed general practice referral behaviour and was cost effective, but patients in the MuIS group were less satisfied. This study supports the application of a MuIS when implementing guidelines. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01699256....

  18. Generalization performance of regularized neural network models

    DEFF Research Database (Denmark)

    Larsen, Jan; Hansen, Lars Kai

    1994-01-01

    Architecture optimization is a fundamental problem of neural network modeling. The optimal architecture is defined as the one which minimizes the generalization error. This paper addresses estimation of the generalization performance of regularized, complete neural network models. Regularization...

  19. [Management of bronchiolitis in general practice and determinants of treatment being discordant with guidelines of the HAS].

    Science.gov (United States)

    Branchereau, E; Branger, B; Launay, E; Verstraete, M; Vrignaud, B; Levieux, K; Senand, R; Gras-Le Guen, C

    2013-12-01

    The Haute autorité de santé released clinical practice guidelines in 2000 to assist in the management of bronchiolitis. These guidelines emphasized supportive care with nasal suctioning and encouraged chest physiotherapy. The aim of this study was to examine the adherence to the french guidelines for the management of bronchiolitis by general practitioners. The study included infants less than 24 months of age with bronchiolitis, consulting a general practitioner in Vendée or in Loire-Atlantique, from November 2011 to April 2012 and whose parents accepted to participate to the study. The primary endpoint was the concordance of therapeutic practice with the french guidelines (administrated treatments, refer to pediatric emergencies). Data were collected through questionaires completed by general practitioners. Of the 1236 questionnaires distributed, 134 were completed and 118 therapeutic practice were analyzed. A total of 52.5% of therapeutic practice were concordant with guidelines and 57.5% in case of first bronchiolitis. 50% of infants with a hospitalization criteria according to the guidelines, have not been, which probably shows the interest of new guidelines, with highlighting of hospitalization criteria. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Prevention of generalized reactions to contrast media: a consensus report and guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Morcos, S.K. [Dept. of Diagnostic Imaging, Northern General Hospital, Sheffield (United Kingdom); Thomsen, H.S. [Dept. of Diagnostic Radiology, Herlev Hospital, University of Copenhagen (Denmark); Webb, J.A.W. [Diagnostic Radiology Department, St. Bartholomew' s Hospital, London (United Kingdom)

    2001-09-01

    The aim of this study was to document, using consensus methodology, current practice for prevention of generalized reactions to contrast media, to identify areas where there is disagreement or confusion and to draw up guidelines for reducing the risk of generalized contrast media reactions based on the survey and a review of the literature. A document with 165 questions was mailed to 202 members of the European Society of Urogenital Radiology. The questions covered risk factors and prophylactic measures for generalized contrast media reactions. Sixty-eight members (34%) responded. The majority indicated that a history of moderate and severe reaction(s) to contrast media and asthma are important risk factors. The survey also indicated that patients with risk factors should receive non-ionic contrast media. In patients at high risk of reaction, if the examination is deemed absolutely necessary, a resuscitation team should be available at the time of the procedure. The majority (91%) used corticosteroid prophylaxis given at least 11 h before contrast medium to patients at increased risk of reaction. The frequency of the dosage varied from one to three times. Fifty-five percent also use antihistamine Hl, mainly administered orally and once. Antihistamine H2 and ephedrine are rarely used. All essential drugs are available on the emergency resuscitation trolley. Patients with risk factors are observed up to 30 min by 48% and up to 60 min by 43% of the responders. Prophylactic measures are not taken before extravascular use of contrast media. Prophylactic drugs are given to patients with a history of moderate or severe generalized reaction to contrast media. In patients with asthma, opinion is divided with only half of the responders giving prophylactic drugs. Aspirin, {beta}-blockers, interleukin-2 and non-steroid anti-inflammatory drugs are not considered risk factors and therefore are not stopped before injection of contrast media. The survey showed some variability in

  1. Prevention of generalized reactions to contrast media: a consensus report and guidelines

    International Nuclear Information System (INIS)

    Morcos, S.K.; Thomsen, H.S.; Webb, J.A.W.

    2001-01-01

    The aim of this study was to document, using consensus methodology, current practice for prevention of generalized reactions to contrast media, to identify areas where there is disagreement or confusion and to draw up guidelines for reducing the risk of generalized contrast media reactions based on the survey and a review of the literature. A document with 165 questions was mailed to 202 members of the European Society of Urogenital Radiology. The questions covered risk factors and prophylactic measures for generalized contrast media reactions. Sixty-eight members (34%) responded. The majority indicated that a history of moderate and severe reaction(s) to contrast media and asthma are important risk factors. The survey also indicated that patients with risk factors should receive non-ionic contrast media. In patients at high risk of reaction, if the examination is deemed absolutely necessary, a resuscitation team should be available at the time of the procedure. The majority (91%) used corticosteroid prophylaxis given at least 11 h before contrast medium to patients at increased risk of reaction. The frequency of the dosage varied from one to three times. Fifty-five percent also use antihistamine Hl, mainly administered orally and once. Antihistamine H2 and ephedrine are rarely used. All essential drugs are available on the emergency resuscitation trolley. Patients with risk factors are observed up to 30 min by 48% and up to 60 min by 43% of the responders. Prophylactic measures are not taken before extravascular use of contrast media. Prophylactic drugs are given to patients with a history of moderate or severe generalized reaction to contrast media. In patients with asthma, opinion is divided with only half of the responders giving prophylactic drugs. Aspirin, β-blockers, interleukin-2 and non-steroid anti-inflammatory drugs are not considered risk factors and therefore are not stopped before injection of contrast media. The survey showed some variability in

  2. General safety guidelines for looking for a low mass activity-long life waste storage site

    International Nuclear Information System (INIS)

    2008-01-01

    The objective of this document is to define general guidelines which must be followed during the stages of search for a site and stages of design of a storage facility for low activity-long life radioactive wastes, in order to ensure its safety after closure. After having specified the considered wastes, geological shapes, and situations, this document defines the fundamental objective and the associated criteria (protection against chemical risk, radioprotection). It presents the design aspects related to safety (safety principles and functions, waste packages, public works engineering, geological environment, storage concepts). The last part deals with the safety demonstration after site closure which includes the control of some components, the assessment of disturbances in the storage facility or due to its presence, the taking of uncertainty and sensitivity studies into account, the influence of natural events

  3. Multivariate generalized linear mixed models using R

    CERN Document Server

    Berridge, Damon Mark

    2011-01-01

    Multivariate Generalized Linear Mixed Models Using R presents robust and methodologically sound models for analyzing large and complex data sets, enabling readers to answer increasingly complex research questions. The book applies the principles of modeling to longitudinal data from panel and related studies via the Sabre software package in R. A Unified Framework for a Broad Class of Models The authors first discuss members of the family of generalized linear models, gradually adding complexity to the modeling framework by incorporating random effects. After reviewing the generalized linear model notation, they illustrate a range of random effects models, including three-level, multivariate, endpoint, event history, and state dependence models. They estimate the multivariate generalized linear mixed models (MGLMMs) using either standard or adaptive Gaussian quadrature. The authors also compare two-level fixed and random effects linear models. The appendices contain additional information on quadrature, model...

  4. Management of Ménière's disease in general practice: adherence to the UK National Health Service 'Prodigy' guidelines.

    Science.gov (United States)

    Smale, E; McDonald, S; Maha, N; Short, S

    2008-08-01

    Dizziness is a common presenting complaint in primary healthcare. One differential diagnosis is Ménière's disease. The UK National Health Service 'Prodigy' guidelines have been produced to help healthcare professionals to diagnose and manage Ménière's disease. The aim of this audit was to consider how Ménière's disease is managed in general practice, and to assess how well general practitioners adhere to the Prodigy guidelines. We identified general practices near the Torbay region of south Devon which had a 'TQ' postcode. There were 41 practices, staffed by a total of 203 general practitioners. We wrote to each general practitioner, asking them to fill in a questionnaire regarding Ménière's disease. Our practice response rate was 68 per cent and our individual rate 43 per cent. The mean correct answer rate was >50 per cent. The respondents achieved this despite few being aware of any formal guidelines, and none being aware of the Prodigy guidelines. Detailed knowledge of Ménière's disease was uncommon, and formal guidelines were not frequently consulted.

  5. Generalized latent variable modeling multilevel, longitudinal, and structural equation models

    CERN Document Server

    Skrondal, Anders; Rabe-Hesketh, Sophia

    2004-01-01

    This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

  6. General introduction to simulation models

    DEFF Research Database (Denmark)

    Hisham Beshara Halasa, Tariq; Boklund, Anette

    2012-01-01

    Monte Carlo simulation can be defined as a representation of real life systems to gain insight into their functions and to investigate the effects of alternative conditions or actions on the modeled system. Models are a simplification of a system. Most often, it is best to use experiments and fie...... as support decision making. However, several other factors affect decision making such as, ethics, politics and economics. Furthermore, the insight gained when models are build leads to point out areas where knowledge is lacking....... of FMD spread that can provide useful and trustworthy advises, there are four important issues, which the model should represent: 1) The herd structure of the country in question, 2) the dynamics of animal movements and contacts between herds, 3) the biology of the disease, and 4) the regulations...

  7. Record of responses to public comments on proposed general guidelines for recommendation of sites for nuclear waste repositories

    International Nuclear Information System (INIS)

    1983-01-01

    The Nuclear Waste Policy Act of 1982 (Public Law 97-425, referred to in this document as the Act) assigned to the US Department of Energy (DOE) the authority for the disposal of high-level radioactive waste and spent nuclear fuel. Among other provisions, the Act specifies a process and schedule for the siting of two geologic repositories for this purpose. The Act requires that the DOE issue general guidelines for the recommendation of sites for repositories. The guidelines are to be developed in consultation with three Federal agencies (the Council on Environmental Quality, the US Environmental Protection Agency, and the US Geological Survey) and with interested Governors and issued with the concurrence of the US Nuclear Regulatory Commission. To meet this directive, the DOE convened a task force of program experts to develop proposed guidelines, issued the proposed guidelines on February 7, 1983, and invited comments from the specified Federal agencies, interested Governors, and the general public. Public hearings on the proposed guidelines were held in March at the following locations: Chicago, New Orleans, Washington, DC, Salt Lake City, and Seattle. After considering the resulting comments and preparing responses to them, the task force prepared a draft of this comment-response document and a set of alternative guidelines; these documents were issued on May 27, 1983. This document summarizes the record of comments that directly led to the alternative guidelines of May 27, 1983. It contains synopses of comments, presents the responses of the task force to the comments, and briefly describes how the proposed guidelines of February 7, 1983, were revised to produce the alternative guidelines of May 27, 1983. 13 references

  8. Interpretation of NCCN Guidelines: General Therapies on Non-small Cell Lung Cancer (Version 6. 2015

    Directory of Open Access Journals (Sweden)

    Xin-en HUANG

    2015-06-01

    Full Text Available Lung cancer is one of the most common malignant tumors in China and ranks the first of cancer-related death. The major etiological agent of lung cancer is an industry-made and promoted addictive product, so lung cancer is considered to be a unique disease in all cancers. Effective policies for public health are required to prevent the smoking initiation so as to reduce the mortality of lung cancer, so Food and Drug Administration (FDA has introduced a series of measures to monitor the tobacco products. As to patients with strong suspicion of lung cancer in stage Ⅰ-Ⅱ, a preoperative biopsy is needed and intra-operative diagnosis is necessary before pneumonectomy, bilobectomy or lobectomy if the preoperative tissue diagnosis is not obtained. However, lung cancer still cannot be easily diagnosed and cured, so the annual improvement and update of new therapeutic protocols and the development of new agents is of great significance. Non-small cell lung cancer (NSCLC accounts for about 80% of all lung cancer, and above 75% NSCLC patients are in middle-advanced stage when diagnosed, so they have lost the optimal therapeutic opportunity and the 5-year survival rate is relatively low. Therefore, this study mainly interpreted the National Comprehensive Cancer Network (NCCN guidelines on the general therapies on NSCLC, hoping to provide references for the treatment of NSCLC patients and prolong their long-term survival.

  9. Actuarial statistics with generalized linear mixed models

    NARCIS (Netherlands)

    Antonio, K.; Beirlant, J.

    2007-01-01

    Over the last decade the use of generalized linear models (GLMs) in actuarial statistics has received a lot of attention, starting from the actuarial illustrations in the standard text by McCullagh and Nelder [McCullagh, P., Nelder, J.A., 1989. Generalized linear models. In: Monographs on Statistics

  10. Generalized Linear Models in Family Studies

    Science.gov (United States)

    Wu, Zheng

    2005-01-01

    Generalized linear models (GLMs), as defined by J. A. Nelder and R. W. M. Wedderburn (1972), unify a class of regression models for categorical, discrete, and continuous response variables. As an extension of classical linear models, GLMs provide a common body of theory and methodology for some seemingly unrelated models and procedures, such as…

  11. Proliferation Risk Characterization Model Prototype Model - User and Programmer Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Dukelow, J.S.; Whitford, D.

    1998-12-01

    A model for the estimation of the risk of diversion of weapons-capable materials was developed. It represents both the threat of diversion and site vulnerability as a product of a small number of variables (two to eight), each of which can take on a small number (two to four) of qualitatively defined (but quantitatively implemented) values. The values of the overall threat and vulnerability variables are then converted to threat and vulnerability categories. The threat and vulnerability categories are used to define the likelihood of diversion, also defined categorically. The evaluator supplies an estimate of the consequences of a diversion, defined categorically, but with the categories based on the IAEA Attractiveness levels. Likelihood and Consequences categories are used to define the Risk, also defined categorically. The threat, vulnerability, and consequences input provided by the evaluator contains a representation of his/her uncertainty in each variable assignment which is propagated all the way through to the calculation of the Risk categories. [Appendix G available on diskette only.

  12. Micro Data and General Equilibrium Models

    DEFF Research Database (Denmark)

    Browning, Martin; Hansen, Lars Peter; Heckman, James J.

    1999-01-01

    Dynamic general equilibrium models are required to evaluate policies applied at the national level. To use these models to make quantitative forecasts requires knowledge of an extensive array of parameter values for the economy at large. This essay describes the parameters required for different...... economic models, assesses the discordance between the macromodels used in policy evaluation and the microeconomic models used to generate the empirical evidence. For concreteness, we focus on two general equilibrium models: the stochastic growth model extended to include some forms of heterogeneity...

  13. Management of spontaneous pneumothorax compared to British Thoracic Society (BTS) 2003 guidelines: a district general hospital audit.

    Science.gov (United States)

    Medford, Andrew Rl; Pepperell, Justin Ct

    2007-10-01

    In 1993, the British Thoracic Society (BTS) issued guidelines for the management of spontaneous pneumothorax (SP). These were refined in 2003. To determine adherence to the 2003 BTS SP guidelines in a district general hospital. An initial retrospective audit of 52 episodes of acute SP was performed. Subsequent intervention involved a junior doctor educational update on both the 2003 BTS guidelines and the initial audit results, and the setting up of an online guideline hyperlink. After the educational intervention a further prospective re-audit of 28 SP episodes was performed. Management of SP deviated considerably from the 2003 BTS guidelines in the initial audit - deviation rate 26.9%. After the intervention, a number of clinical management deviations persisted (32.1% deviation rate); these included failure to insert a chest drain despite unsuccessful aspiration, and attempting aspiration of symptomatic secondary SPs. Specific tools to improve standards might include a pneumothorax proforma to improve record keeping and a pneumothorax care pathway to reduce management deviations compared to BTS guidelines. Successful change also requires identification of the total target audience for any educational intervention.

  14. A general consumer-resource population model

    Science.gov (United States)

    Lafferty, Kevin D.; DeLeo, Giulio; Briggs, Cheryl J.; Dobson, Andrew P.; Gross, Thilo; Kuris, Armand M.

    2015-01-01

    Food-web dynamics arise from predator-prey, parasite-host, and herbivore-plant interactions. Models for such interactions include up to three consumer activity states (questing, attacking, consuming) and up to four resource response states (susceptible, exposed, ingested, resistant). Articulating these states into a general model allows for dissecting, comparing, and deriving consumer-resource models. We specify this general model for 11 generic consumer strategies that group mathematically into predators, parasites, and micropredators and then derive conditions for consumer success, including a universal saturating functional response. We further show how to use this framework to create simple models with a common mathematical lineage and transparent assumptions. Underlying assumptions, missing elements, and composite parameters are revealed when classic consumer-resource models are derived from the general model.

  15. Conformity and Dissonance in Generalized Voter Models

    Science.gov (United States)

    Page, Scott E.; Sander, Leonard M.; Schneider-Mizell, Casey M.

    2007-09-01

    We generalize the voter model to include social forces that produce conformity among voters and avoidance of cognitive dissonance of opinions within a voter. The time for both conformity and consistency (which we call the exit time) is, in general, much longer than for either process alone. We show that our generalized model can be applied quite widely: it is a form of Wright's island model of population genetics, and is related to problems in the physical sciences. We give scaling arguments, numerical simulations, and analytic estimates for the exit time for a range of relative strengths in the tendency to conform and to avoid dissonance.

  16. General Guidelines on Criteria for Adoption or Rejection of Evaluated Libraries and Data by the Nuclear Data Team

    Energy Technology Data Exchange (ETDEWEB)

    Neudecker, Denise [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Conlin, Jeremy Lloyd [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gray, Mark Girard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); McCartney, Austin Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parsons, Donald Kent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); White, Morgan Curtis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-04-12

    This memo contains general guidelines on what documentation and tools need to be in place as well as format and data testing requirements such that evaluated nuclear data sets or entire libraries can be adopted by the nuclear data team. Additional requirements beyond this memo might apply for specific nuclear data observables. These guidelines were established based on discussions between J.L. Conlin, M.G. Gray, A.P. McCartney, D. Neudecker, D.K. Parsons and M.C. White.

  17. GENERAL GUIDELINES CONCERNING THE RELATION INTERNATIONAL INTELLECTUAL PROPERTY BUSINESS VERSUS HUMAN RIGHTS AND CIVIL LIBERTIES

    Directory of Open Access Journals (Sweden)

    Speriusi-Vlad Alin

    2014-07-01

    Full Text Available Today, the intellectual property protection is no longer an absolute social and legal that justifies adoption of any measures necessary to protect it. Initially seen as the prerequisite for sustainable development, implementation of new technologies, and encouragement of international trade, the intellectual property, especially prior to ACTA (Anti-Counterfeiting Trade Agreement international trial implementation, and also thereafter, was increasingly identified as a source of violation of fundamental rights and civil liberties, i.e. the right to protection of personal data, the right to privacy, freedom to send and receive information freedom of information, freedom to contract, and freedom to carry out economic activities (freedom of commerce. As far as international trade transactions have often a component of intellectual property that requires to be protected, it is necessary to identify the landmarks, the rules establishing de facto limits in order to protect the intellectual property without risk of infringement of fundamental rights and civil liberties of other persons, in particular users or potential users of goods and services incorporating intellectual property. The best guidelines in this regard may be provided by the CJEU (Court of Justice of the European Union case-law both due to its reasoning underlying the decision of the Parliament to reject ACTA ratification and the fact that the case-law of this Court, especially the most recent one, is highly complex and nuanced, not denying in any way the importance of intellectual property, and identifying certain cases where their primacy persist and whose analysis leads to laying down some general rules in the field.

  18. A Generalized Random Regret Minimization Model

    NARCIS (Netherlands)

    Chorus, C.G.

    2013-01-01

    This paper presents, discusses and tests a generalized Random Regret Minimization (G-RRM) model. The G-RRM model is created by replacing a fixed constant in the attribute-specific regret functions of the RRM model, by a regret-weight variable. Depending on the value of the regret-weights, the G-RRM

  19. Communicative skills of general practitioners augment the effectiveness of guideline-based depression treatment

    NARCIS (Netherlands)

    van Os, TWDP; van den Brink, RHS; Tiemens, BG; Jenner, JA; van der Meer, K; Ormel, J

    Background: Although good physician communication is associated with positive patient outcomes. it does not figure in current depression treatment guidelines. We examined the effect of depression treatment. communicative skills and their interaction on patient outcomes for depression in primary

  20. An integrated continuous improvement model of TPM, TPS and TQM for boosting profitability of manufacturing industries: An innovative model & guideline

    OpenAIRE

    Haftu Hailu; Solomon Mengstu; Tewedros Hailu

    2018-01-01

    The purpose of this research is to develop an integrated literature based TPM, TPS and TQM mod-el through PDCA cycle, and implementation guideline for the implementation of the model. At this time very few studies are available on this research area, even this research on integrated model of TPM, TPS and TQM practices, and implementation guideline are not corresponding. The method-ology to develop the model and the implementation guideline is based on identifying the uniqueness and common pra...

  1. EOP MIT General Circulation Model (MITgcm)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data contains a regional implementation of the Massachusetts Institute of Technology general circulation model (MITgcm) at a 1-km spatial resolution for the...

  2. Generalized Reduced Order Model Generation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — M4 Engineering proposes to develop a generalized reduced order model generation method. This method will allow for creation of reduced order aeroservoelastic state...

  3. Generalized Reduced Order Model Generation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — M4 Engineering proposes to develop a generalized reduced order model generation method. This method will allow for creation of reduced order aeroservoelastic state...

  4. Empirical generalization assessment of neural network models

    DEFF Research Database (Denmark)

    Larsen, Jan; Hansen, Lars Kai

    1995-01-01

    competing models. Since all models are trained on the same data, a key issue is to take this dependency into account. The optimal split of the data set of size N into a cross-validation set of size Nγ and a training set of size N(1-γ) is discussed. Asymptotically (large data sees), γopt→1......This paper addresses the assessment of generalization performance of neural network models by use of empirical techniques. We suggest to use the cross-validation scheme combined with a resampling technique to obtain an estimate of the generalization performance distribution of a specific model....... This enables the formulation of a bulk of new generalization performance measures. Numerical results demonstrate the viability of the approach compared to the standard technique of using algebraic estimates like the FPE. Moreover, we consider the problem of comparing the generalization performance of different...

  5. Foundations of linear and generalized linear models

    CERN Document Server

    Agresti, Alan

    2015-01-01

    A valuable overview of the most important ideas and results in statistical analysis Written by a highly-experienced author, Foundations of Linear and Generalized Linear Models is a clear and comprehensive guide to the key concepts and results of linear statistical models. The book presents a broad, in-depth overview of the most commonly used statistical models by discussing the theory underlying the models, R software applications, and examples with crafted models to elucidate key ideas and promote practical model building. The book begins by illustrating the fundamentals of linear models,

  6. Perturbed generalized multicritical one-matrix models

    Science.gov (United States)

    Ambjørn, J.; Chekhov, L.; Makeenko, Y.

    2018-03-01

    We study perturbations around the generalized Kazakov multicritical one-matrix model. The multicritical matrix model has a potential where the coefficients of zn only fall off as a power 1 /n s + 1. This implies that the potential and its derivatives have a cut along the real axis, leading to technical problems when one performs perturbations away from the generalized Kazakov model. Nevertheless it is possible to relate the perturbed partition function to the tau-function of a KdV hierarchy and solve the model by a genus expansion in the double scaling limit.

  7. GENERALIZED VISCOPLASTIC MODELING OF DEBRIS FLOW.

    Science.gov (United States)

    Chen, Cheng-lung

    1988-01-01

    The earliest model developed by R. A. Bagnold was based on the concept of the 'dispersive' pressure generated by grain collisions. Some efforts have recently been made by theoreticians in non-Newtonian fluid mechanics to modify or improve Bagnold's concept or model. A viable rheological model should consist both of a rate-independent part and a rate-dependent part. A generalized viscoplastic fluid (GVF) model that has both parts as well as two major rheological properties (i. e. , the normal stress effect and soil yield criterion) is shown to be sufficiently accurate, yet practical for general use in debris-flow modeling. In fact, Bagnold's model is found to be only a particular case of the GVF model. analytical solutions for (steady) uniform debris flows in wide channels are obtained from the GVF model based on Bagnold's simplified assumption of constant grain concentration.

  8. Preventive evidence into practice (PEP study: implementation of guidelines to prevent primary vascular disease in general practice protocol for a cluster randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Harris Mark F

    2013-01-01

    Full Text Available Abstract Background There are significant gaps in the implementation and uptake of evidence-based guideline recommendations for cardiovascular disease (CVD and diabetes in Australian general practice. This study protocol describes the methodology for a cluster randomised trial to evaluate the effectiveness of a model that aims to improve the implementation of these guidelines in Australian general practice developed by a collaboration between researchers, non-government organisations, and the profession. Methods We hypothesise that the intervention will alter the behaviour of clinicians and patients resulting in improvements of recording of lifestyle and physiological risk factors (by 20% and increased adherence to guideline recommendations for: the management of CVD and diabetes risk factors (by 20%; and lifestyle and physiological risk factors of patients at risk (by 5%. Thirty-two general practices will be randomised in a 1:1 allocation to receive either the intervention or continue with usual care, after stratification by state. The intervention will be delivered through: small group education; audit of patient records to determine preventive care; and practice facilitation visits adapted to the needs of the practices. Outcome data will be extracted from electronic medical records and patient questionnaires, and qualitative evaluation from provider and patient interviews. Discussion We plan to disseminate study findings widely and directly inform implementation strategies by governments, professional bodies, and non-government organisations including the partner organisations.

  9. Examining IS Curriculum Profiles and the IS 2010 Model Curriculum Guidelines in AACSB-Accredited Schools

    Science.gov (United States)

    Mills, Robert J.; Velasquez, Nicole Forsgren; Fadel, Kelly J.; Bell, Corbin C.

    2012-01-01

    The IS 2010 Model Curriculum Guidelines were developed to provide recommendations for standardized information systems curricula while simultaneously allowing for customization within individual programs. While some studies have examined program adherence to the IS 2010 Model Curriculum Guidelines, a more detailed analysis of IS curriculum…

  10. General practitioner's reported use of clinical guidelines for hypertension and ambulatory blood pressure.

    LENUS (Irish Health Repository)

    Flynn, E

    2012-03-01

    ABPM is an invaluable clinical tool, as it has been shown to improve blood pressure control in primary care. Many clinical guidelines for hypertension advocate ambulatory blood pressure monitoring. This study aims to quantify the use of clinical guidelines for hypertension and to explore the role of ABPM in Primary Care. A questionnaire survey was sent to GPs working in the West of Ireland. 88% (n=139) of GPs use clinical guidelines that recommend the use of ABPM. 82% (n=130) of GPs find use of clinic blood pressure monitoring insufficient for the diagnosis and monitoring of hypertension. Despite good access to ABPM, GPs report lack of remuneration, 72% (n=116), cost 68% (n=108), and lack of time, 51% (n=83) as the main limiting factors to use of ABPM. GPs recognise the clinical value of ABPM, but this study identifies definite barriers to the use of ABPM in Primary Care.

  11. Generalization of the quark rearrangement model

    International Nuclear Information System (INIS)

    Fields, T.; Chen, C.K.

    1976-01-01

    An extension and generalization of the quark rearrangement model of baryon annihilation is described which can be applied to all annihilation reactions and which incorporates some of the features of the highly successful quark parton model. Some p anti-p interactions are discussed

  12. Geometrical efficiency in computerized tomography: generalized model

    International Nuclear Information System (INIS)

    Costa, P.R.; Robilotta, C.C.

    1992-01-01

    A simplified model for producing sensitivity and exposure profiles in computerized tomographic system was recently developed allowing the forecast of profiles behaviour in the rotation center of the system. The generalization of this model for some point of the image plane was described, and the geometrical efficiency could be evaluated. (C.G.C.)

  13. [CAVE - A checklist system for preoperative risk evaluation : Guideline-conform cardiopulmonary diagnostics before general and visceral surgical interventions].

    Science.gov (United States)

    Schwenk, W; Hoffmann, P C

    2017-12-01

    Preoperative evaluation of patient risk is an essential component of patient preparation before surgery. Guidelines provide evidence-based algorithms for preoperative assessment of cardiac risk; however, even experienced physicians correctly apply evidence-based algorithms in only 50% of all cases or less. A checklist system for guideline-based cardiopulmonary risk evaluation in adult patients undergoing abdominal or visceral surgery (CAVE checklists) was created to assist in preoperative cardiopulmonary risk assessment and increase correct application of evidence-based algorithms before elective visceral surgery. International guidelines were transformed into a checklist system. These checklists were than evaluated in a department of general and visceral surgery. The main goal was to determine whether preoperative examinations, such as electrocardiograph (ECG), chest-x-ray, spirometry and advanced assessment by a cardiologist, are performed according to evidence-based guidelines. The frequency of recommended as well as unnecessary and missed examinations was assessed. In this study 541 patients with a median age of 64.5 years (interquartile range: 52-73 years) were examined using the checklist system. Of the patients 90.4% underwent ECG and 98.5% chest-X-ray as recommended in the guidelines. Spirometry was not recommended in any patient and not performed in any case. Advanced assessment by a cardiologist was performed in 45.5% of cases as recommended in the guidelines. When guidelines did not recommend ECG, x‑ray, spirometry or advanced cardiac assessment, 69.4%, 99.6%, 99.3% and 99.8% of patients, respectively, actually did not receive these examinations. Only 2.8% of all patients did not receive an examination that was recommended by the guidelines: 1.5% ECG, 0.2% x‑ray and 1.1% advanced cardiological assessment. None of these patients suffered from postoperative cardiopulmonary complications. These simple checklists are easy to use and provide a

  14. Generalized linear model for partially ordered data.

    Science.gov (United States)

    Zhang, Qiang; Ip, Edward Haksing

    2012-01-13

    Within the rich literature on generalized linear models, substantial efforts have been devoted to models for categorical responses that are either completely ordered or completely unordered. Few studies have focused on the analysis of partially ordered outcomes, which arise in practically every area of study, including medicine, the social sciences, and education. To fill this gap, we propose a new class of generalized linear models--the partitioned conditional model--that includes models for both ordinal and unordered categorical data as special cases. We discuss the specification of the partitioned conditional model and its estimation. We use an application of the method to a sample of the National Longitudinal Study of Youth to illustrate how the new method is able to extract from partially ordered data useful information about smoking youths that is not possible using traditional methods. Copyright © 2011 John Wiley & Sons, Ltd.

  15. Management of COPD in general practice in Denmark--participating in an educational program substantially improves adherence to guidelines

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Hansen, Ejvind Frausing; Jensen, Michael Skov

    2010-01-01

    BACKGROUND AND AIM: The general practitioner (GP) is the first contact with the health care system for most patients with COPD in Denmark. We studied, if participating in an educational program could improve adherence to guidelines, not least for diagnosis, staging, and treatment of the disease....... DESIGN AND SETTING: Two cross-sectional surveys were performed precisely one year apart before and after an educational program for the participating GPs. A total of 124 GPs completed the study; 1716 and 1342 patients with GP-diagnosed COPD and no concomitant asthma, respectively, were included...... activity, and referral for rehabilitation; use of inhaled corticosteroids in patients with mild COPD (FEV(1) > 80%pred) declined from 76% to 45%. CONCLUSION: Diagnosis and management of COPD in general practice in Denmark is not according to guidelines, but substantial improvements can be achieved...

  16. Prospective multicentre systematic guideline-based management of patients referred to the Syncope Units of general hospitals.

    Science.gov (United States)

    Brignole, Michele; Ungar, Andrea; Casagranda, Ivo; Gulizia, Michele; Lunati, Maurizio; Ammirati, Fabrizio; Del Rosso, Attilio; Sasdelli, Massimo; Santini, Massimo; Maggi, Roberto; Vitale, Elena; Morrione, Alessandro; Francese, Giuseppina Maura; Vecchi, Maria Rita; Giada, Franco

    2010-01-01

    Although an organizational model for syncope management facilities was proposed in the 2004 guidelines of the European Society of Cardiology (ESC), its implementation in clinical practice and its effectiveness are largely unknown. This prospective study enrolled 941 consecutive patients referred to the Syncope Units of nine general hospitals from 15 March 2008 to 15 September 2008. A median of 15 patients per month were examined in each unit, but the five older units had a two-fold higher volume of activity than the four newer ones (instituted diagnosis was established on initial evaluation in 191 (21%) patients and early by means of 2.9 +/- 1.6 tests in 541 (61%) patients. A likely reflex cause was established in 67%, orthostatic hypotension in 4%, cardiac in 6% and non-syncopal in 5% of the cases. The cause of syncope remained unexplained in 159 (18%) patients, despite a mean of 3.5 +/- 1.8 tests per patient. These latter patients were older, more frequently had structural heart disease or electrocardiographic abnormalities, unpredictable onset of syncope due to the lack of prodromes, and higher OESIL and EGSIS risk scores than the other groups of patients. The mean costs of diagnostic evaluation was 209 euro per outpatient and 1073 euro per inpatient. The median cost of hospital stay was 2990 euro per patient. We documented the current practice of syncope management in specialized facilities that have adopted the management model proposed by the ESC. The results are useful for those who wish to replicate this model in other hospitals. Syncope remains unexplained during in-hospital evaluation in more complex cases at higher risk.

  17. An integrated continuous improvement model of TPM, TPS and TQM for boosting profitability of manufacturing industries: An innovative model & guideline

    Directory of Open Access Journals (Sweden)

    Haftu Hailu

    2018-01-01

    Full Text Available The purpose of this research is to develop an integrated literature based TPM, TPS and TQM mod-el through PDCA cycle, and implementation guideline for the implementation of the model. At this time very few studies are available on this research area, even this research on integrated model of TPM, TPS and TQM practices, and implementation guideline are not corresponding. The method-ology to develop the model and the implementation guideline is based on identifying the uniqueness and common practices of TPM, TPS and TQM systems, existing practice of the integration and implementation guideline, identifying the existing gaps on the model and implementation guideline, developing new integrated TPM, TPS and TQM practice model, and implementation guideline. Previous very few studies of uniqueness, common practices and implementation guideline of the three systems are preserved. The findings of this research, an integrated cutting-edge model of TPM, TPS and TQM practices and implementation guidelines are developed. The originality / value of the developed model and implementation guideline enable manufacturing industries continuously to be competitive and profitable.

  18. Adherence to guidelines on cervical cancer screening in general practice : programme elements of successful implementation

    NARCIS (Netherlands)

    Hermens, R P; Hak, E; Hulscher, M E; Braspenning, J C; Grol, R P

    2001-01-01

    BACKGROUND: There is still only limited understanding of whether and why interventions to facilitate the implementation of guidelines for improving primary care are successful. It is therefore important to look inside the 'black box' of the intervention, to ascertain which elements work well or less

  19. Topics in the generalized vector dominance model

    International Nuclear Information System (INIS)

    Chavin, S.

    1976-01-01

    Two topics are covered in the generalized vector dominance model. In the first topic a model is constructed for dilepton production in hadron-hadron interactions based on the idea of generalized vector-dominance. It is argued that in the high mass region the generalized vector-dominance model and the Drell-Yan parton model are alternative descriptions of the same underlying physics. In the low mass regions the models differ; the vector-dominance approach predicts a greater production of dileptons. It is found that the high mass vector mesons which are the hallmark of the generalized vector-dominance model make little contribution to the large yield of leptons observed in the transverse-momentum range 1 less than p/sub perpendicular/ less than 6 GeV. The recently measured hadronic parameters lead one to believe that detailed fits to the data are possible under the model. The possibility was expected, and illustrated with a simple model the extreme sensitivity of the large-p/sub perpendicular/ lepton yield to the large-transverse-momentum tail of vector-meson production. The second topic is an attempt to explain the mysterious phenomenon of photon shadowing in nuclei utilizing the contribution of the longitudinally polarized photon. It is argued that if the scalar photon anti-shadows, it could compensate for the transverse photon, which is presumed to shadow. It is found in a very simple model that the scalar photon could indeed anti-shadow. The principal feature of the model is a cancellation of amplitudes. The scheme is consistent with scalar photon-nucleon data as well. The idea is tested with two simple GVDM models and finds that the anti-shadowing contribution of the scalar photon is not sufficient to compensate for the contribution of the transverse photon. It is found doubtful that the scalar photon makes a significant contribution to the total photon-nuclear cross section

  20. Exploring the possibility of modeling a genetic counseling guideline using agile methodology.

    Science.gov (United States)

    Choi, Jeeyae

    2013-01-01

    Increased demand of genetic counseling services heightened the necessity of a computerized genetic counseling decision support system. In order to develop an effective and efficient computerized system, modeling of genetic counseling guideline is an essential step. Throughout this pilot study, Agile methodology with United Modeling Language (UML) was utilized to model a guideline. 13 tasks and 14 associated elements were extracted. Successfully constructed conceptual class and activity diagrams revealed that Agile methodology with UML was a suitable tool to modeling a genetic counseling guideline.

  1. Nuclear Waste Policy Act of 1982; proposed general guidelines for recommendation of sites for nuclear waste repositories

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    In accordance with the requirements of the Nuclear Waste Policy Act of 1982 (Pub. L. 97-425), hereinafter referred to as the Act, the Department of Energy is proposing general guidelines for the recommendation of sites for repositories for disposal of high-level radioactive waste and spent nuclear fuel in geologic formations. These guidelines are based on the criteria that the Department has used in its National Waste Terminal Storage program, the criteria proposed by the Nuclear Regulatory Commission (NRC), and the environmental standards proposed by the Environmental Protection Agency. These guidelines establish the performance requirements for a geologic repository system, specify how the Department will implement its site-selection program, and define the technical qualifications that candidate sites must meet in the various steps of the site-selection process mandated by the Act. After considering comments from the public; consulting with the Council on Environmental Quality, the Administrator of the Environmental Protection Agency, the Director of the Geological Survey, and interested Governors; and obtaining NRC concurrence, the Department will issue these guidelines in final form as a new Part 960 to Title 10 of the Code of Federal Regulations (10 CFR Part 960)

  2. Direct mail improves knowledge of basic life support guidelines in general practice

    DEFF Research Database (Denmark)

    Secher, Niels; Mikkelsen, Mette Marie; Adelborg, Kasper

    2012-01-01

    Dette studie viste, at ved at fremsende vejledning i basal genoplivning direkte til alment praktiserende læger var det muligt at øge lægernes viden om dette område samt implementere de nye guidelines på området. Enhver praktiserende læge er til stadighed i kontakt med personer, der potentielt kan...

  3. Generalizations of the noisy-or model

    Czech Academy of Sciences Publication Activity Database

    Vomlel, Jiří

    2015-01-01

    Roč. 51, č. 3 (2015), s. 508-524 ISSN 0023-5954 R&D Projects: GA ČR GA13-20012S Institutional support: RVO:67985556 Keywords : Bayesian networks * noisy-or model * classification * generalized linear models Subject RIV: JD - Computer Applications, Robotics Impact factor: 0.628, year: 2015 http://library.utia.cas.cz/separaty/2015/MTR/vomlel-0447357.pdf

  4. Toward General Analysis of Recursive Probability Models

    OpenAIRE

    Pless, Daniel; Luger, George

    2013-01-01

    There is increasing interest within the research community in the design and use of recursive probability models. Although there still remains concern about computational complexity costs and the fact that computing exact solutions can be intractable for many nonrecursive models and impossible in the general case for recursive problems, several research groups are actively developing computational techniques for recursive stochastic languages. We have developed an extension to the traditional...

  5. A generalized mechanical model for suture interfaces of arbitrary geometry

    Science.gov (United States)

    Li, Yaning; Ortiz, Christine; Boyce, Mary C.

    2013-04-01

    Suture interfaces with a triangular wave form commonly found in nature have recently been shown to exhibit exceptional mechanical behavior, where geometric parameters such as amplitude, frequency, and hierarchy can be used to nonlinearly tailor and amplify mechanical properties. In this study, using the principle of complementary virtual work, we formulate a generalized, composite mechanical model for arbitrarily-shaped interdigitating suture interfaces in order to more broadly investigate the influence of wave-form geometry on load transmission, deformation mechanisms, anisotropy, and stiffness, strength, and toughness of the suture interface for tensile and shear loading conditions. The application of this suture interface model is exemplified for the case of the general trapezoidal wave-form. Expressions for the in-plane stiffness, strength and fracture toughness and failure mechanisms are derived as nonlinear functions of shape factor β (which characterizes the general trapezoidal shape as triangular, trapezoidal, rectangular or anti-trapezoidal), the wavelength/amplitude ratio, the interface width/wavelength ratio, and the stiffness and strength ratios of the skeletal/interfacial phases. These results provide guidelines for choosing and tailoring interface geometry to optimize the mechanical performance in resisting different loads. The presented model provides insights into the relation between the mechanical function and the morphological diversity of suture interface geometries observed in natural systems.

  6. General Equilibrium Models: Improving the Microeconomics Classroom

    Science.gov (United States)

    Nicholson, Walter; Westhoff, Frank

    2009-01-01

    General equilibrium models now play important roles in many fields of economics including tax policy, environmental regulation, international trade, and economic development. The intermediate microeconomics classroom has not kept pace with these trends, however. Microeconomics textbooks primarily focus on the insights that can be drawn from the…

  7. A new management of syncope: prospective systematic guideline-based evaluation of patients referred urgently to general hospitals.

    Science.gov (United States)

    Brignole, Michele; Menozzi, Carlo; Bartoletti, Angelo; Giada, Franco; Lagi, Alfonso; Ungar, Andrea; Ponassi, Irene; Mussi, Chiara; Maggi, Roberto; Re, Giuseppe; Furlan, Raffaello; Rovelli, Gianni; Ponzi, Patrizia; Scivales, Alessandro

    2006-01-01

    The guidelines of the European Society of Cardiology (ESC) define the current standard for the management of syncope, but are still incompletely applied in the clinical setting. Prospective systematic evaluation, on strict adherence to the guidelines, of consecutive patients referred for syncope to the emergency departments of 11 general hospitals. In order to maximize the application, a decision-making guideline-based software was used and trained core medical personnel were designated-both locally in each hospital and centrally-to verify adherence to the diagnostic pathway and give advice on its correction. A diagnostic work-up consistent with the guidelines was completed in 465/541 patients (86%). A definite diagnosis was established in 98% (unexplained in 2%): neurally mediated syncope accounted for 66% of diagnosis, orthostatic hypotension 10%, primary arrhythmias 11%, structural cardiac or cardiopulmonary disease 5%, and non-syncopal attacks 6%, respectively. The initial evaluation (consisting of history, physical examination, and standard electrocardiogram) established a diagnosis in 50% of cases. Hospitalization for the management of syncope was appropriate in 25% and was required for other reasons in a further 13% of cases. The median in-hospital stay was 5.5 days (interquartile range, 3-9). Apart from the initial evaluation, a mean of 1.9+/-1.1 appropriate tests per patient was performed in 193 patients and led to a final diagnosis in 182 of these (94%). The results of this study assess the current standard for the management of syncope on the basis of a rigorous adherence to guidelines of the ESC and provide a frame of reference for daily activity when dealing with syncope.

  8. [Summary of the practice guideline 'Viral hepatitis and other liver diseases' (second revision) from the Dutch College of General Practitioners].

    Science.gov (United States)

    Bouma, M; van Geldrop, W J; Numans, M E; Wiersma, Tj; Goudswaard, A N

    2008-12-06

    The revised Dutch College of General Practitioners' practice guideline 'Viral hepatitis and other liver diseases' offers advice in the diagnosis and management of viral hepatitis A, B and C and other liver diseases. The guideline is important for general practitioners as well as specialists in internal medicine and gastroenterology. The emphasis is on the management of chronic hepatitis B en C, because the prevalence of these diseases has increased in the Netherlands and, in addition, the treatment options for chronic hepatitis have improved. Consequently, timely recognition and adequate referral of patients with chronic hepatitis B or hepatitis C have become more important. However, many patients with a chronic liver disease have no symptoms. Therefore, the general practitioner should be aware that a patient visiting the practice with fatigue and malaise could have a liver disease if he or she belongs to a high-risk group or has had high-risk contacts. If the general practitioner repeatedly finds increased liver transaminase values during routine examination of asymptomatic patients, additional diagnostic tests should be performed. Further tests should focus on viral hepatitis as well as on non-alcoholic fatty liver disease and non-alcoholic steatohepatitis or, depending on the history-taking, liver damage due to excessive alcohol, medication or drug use.

  9. Conformity to the surviving sepsis campaign international guidelines among physicians in a general intensive care unit in Nairobi.

    Science.gov (United States)

    Mung'ayi, V; Karuga, R

    2010-08-01

    There are emerging therapies for managing septic critically-ill patients. There is little data from the developing world on their usage. To determine the conformity rate for resuscitation and management bundles for septic patients amongst physicians in a general intensive care unit. Cross sectional observational study. The general intensive care unit, Aga Khan University Hospital,Nairobi. Admitting physicians from all specialties in the general intensive care unit. The physicians had high conformity rates of 92% and 96% for the fluid resuscitation and use of va so pressors respectively for the initial resuscitation bundle. They had moderate conformity rates for blood cultures prior to administering antibiotics (57%) and administration of antibiotics within first hour of recognition of septic shock (54%). There was high conformity rate to the glucose control policy (81%), use of protective lung strategy in acute lung injury/Acute respiratory distress syndrome, venous thromboembolism prophylaxis (100%) and stress ulcer prophylaxis (100%) in the management bundle. Conformity was moderate for use of sedation, analgesia and muscle relaxant policy (69%), continuous renal replacement therapies (54%) and low for steroid policy (35%), administration ofdrotrecogin alfa (0%) and selective digestive decontamination (15%). There is varying conformity to the international sepsis guidelines among physicians caring for patients in our general ICU. Since increased conformity would improve survival and reduce morbidity, there is need for sustained education and guideline based performance improvement.

  10. General guidelines for medically screening mixed population groups potentially exposed to nerve or vesicant agents

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.; Munro, N.B. (Oak Ridge National Lab., TN (United States)); Sidell, F.R. (Army Medical Research Inst. of Chemical Defense, Aberdeen Proving Ground, MD (United States)); Leffingwell, S.S. (Centers for Disease Control, Atlanta, GA (United States). Center for Environmental Health and Injury Control)

    1992-01-01

    A number of state and local planners have requested guidance on screening protocols and have expressed interest in sampling body fluids from exposed or potentially exposed individuals as a means of estimating agent dose. These guidelines have been developed to provide a clear statement that could be used by state and local emergency response personnel in the event of a nerve or vesicant agent incident resulting in off-post contamination; maximum protection from harm is the goal. The assumption is that any population group so exposed would be heterogeneous for age, gender, reproductive status, and state of health.

  11. Consensus-based training and assessment model for general surgery.

    Science.gov (United States)

    Szasz, P; Louridas, M; de Montbrun, S; Harris, K A; Grantcharov, T P

    2016-05-01

    Surgical education is becoming competency-based with the implementation of in-training milestones. Training guidelines should reflect these changes and determine the specific procedures for such milestone assessments. This study aimed to develop a consensus view regarding operative procedures and tasks considered appropriate for junior and senior trainees, and the procedures that can be used as technical milestone assessments for trainee progression in general surgery. A Delphi process was followed where questionnaires were distributed to all 17 Canadian general surgery programme directors. Items were ranked on a 5-point Likert scale, with consensus defined as Cronbach's α of at least 0·70. Items rated 4 or above on the 5-point Likert scale by 80 per cent of the programme directors were included in the models. Two Delphi rounds were completed, with 14 programme directors taking part in round one and 11 in round two. The overall consensus was high (Cronbach's α = 0·98). The training model included 101 unique procedures and tasks, 24 specific to junior trainees, 68 specific to senior trainees, and nine appropriate to all. The assessment model included four procedures. A system of operative procedures and tasks for junior- and senior-level trainees has been developed along with an assessment model for trainee progression. These can be used as milestones in competency-based assessments. © 2016 BJS Society Ltd Published by John Wiley & Sons Ltd.

  12. Methodological guidelines

    International Nuclear Information System (INIS)

    Halsnaes, K.; Callaway, J.M.; Meyer, H.J.

    1999-01-01

    The guideline document establishes a general overview of the main components of climate change mitigation assessment. This includes an outline of key economic concepts, scenario structure, common assumptions, modelling tools and country study assumptions. The guidelines are supported by Handbook Reports that contain more detailed specifications of calculation standards, input assumptions and available tools. The major objectives of the project have been provided a methodology, an implementing framework and a reporting system which countries can follow in meeting their future reporting obligations under the FCCC and for GEF enabling activities. The project builds upon the methodology development and application in the UNEP National Abatement Coasting Studies (UNEP, 1994a). The various elements provide countries with a road map for conducting climate change mitigation studies and submitting national reports as required by the FCCC. (au) 121 refs

  13. Methodological guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Halsnaes, K.; Callaway, J.M.; Meyer, H.J.

    1999-04-01

    The guideline document establishes a general overview of the main components of climate change mitigation assessment. This includes an outline of key economic concepts, scenario structure, common assumptions, modelling tools and country study assumptions. The guidelines are supported by Handbook Reports that contain more detailed specifications of calculation standards, input assumptions and available tools. The major objectives of the project have been provided a methodology, an implementing framework and a reporting system which countries can follow in meeting their future reporting obligations under the FCCC and for GEF enabling activities. The project builds upon the methodology development and application in the UNEP National Abatement Coasting Studies (UNEP, 1994a). The various elements provide countries with a road map for conducting climate change mitigation studies and submitting national reports as required by the FCCC. (au) 121 refs.

  14. [Less ethnic knowledge in the Dutch College of General Practitioner's practice guidelines on type 2 diabetes mellitus, hypertension and asthma in adults than in the supporting literature

    NARCIS (Netherlands)

    Manna, D.R.; Bruijnzeels, M.A.; Mokkink, H.G.A.; Berg, M. van den

    2003-01-01

    OBJECTIVE: To assess whether ethnic differences present in the scientific literature used as the basis for the Dutch College of General Practitioner's (NHG) practice guidelines were reflected in the ethnic-specific information the guidelines contained. DESIGN: Analysis of published information.

  15. General Business Model Patterns for Local Energy Management Concepts

    International Nuclear Information System (INIS)

    Facchinetti, Emanuele; Sulzer, Sabine

    2016-01-01

    The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

  16. General business model patterns for Local Energy Management concepts

    Directory of Open Access Journals (Sweden)

    Emanuele eFacchinetti

    2016-03-01

    Full Text Available The transition towards a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed and compared. Through a market review a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

  17. General regression and representation model for classification.

    Directory of Open Access Journals (Sweden)

    Jianjun Qian

    Full Text Available Recently, the regularized coding-based classification methods (e.g. SRC and CRC show a great potential for pattern classification. However, most existing coding methods assume that the representation residuals are uncorrelated. In real-world applications, this assumption does not hold. In this paper, we take account of the correlations of the representation residuals and develop a general regression and representation model (GRR for classification. GRR not only has advantages of CRC, but also takes full use of the prior information (e.g. the correlations between representation residuals and representation coefficients and the specific information (weight matrix of image pixels to enhance the classification performance. GRR uses the generalized Tikhonov regularization and K Nearest Neighbors to learn the prior information from the training data. Meanwhile, the specific information is obtained by using an iterative algorithm to update the feature (or image pixel weights of the test sample. With the proposed model as a platform, we design two classifiers: basic general regression and representation classifier (B-GRR and robust general regression and representation classifier (R-GRR. The experimental results demonstrate the performance advantages of proposed methods over state-of-the-art algorithms.

  18. Current definition and a generalized federbush model

    International Nuclear Information System (INIS)

    Singh, L.P.S.; Hagen, C.R.

    1978-01-01

    The Federbush model is studied, with particular attention being given to the definition of currents. Inasmuch as there is no a priori restriction of local gauge invariance, the currents in the interacting case can be defined more generally than in Q.E.D. It is found that two arbitrary parameters are thereby introduced into the theory. Lowest order perturbation calculations for the current correlation functions and the Fermion propagators indicate that the theory admits a whole class of solutions dependent upon these parameters with the closed solution of Federbush emerging as a special case. The theory is shown to be locally covariant, and a conserved energy--momentum tensor is displayed. One finds in addition that the generators of gauge transformations for the fields are conserved. Finally it is shown that the general theory yields the Federbush solution if suitable Thirring model type counterterms are added

  19. Generalized Additive Models for Nowcasting Cloud Shading

    Czech Academy of Sciences Publication Activity Database

    Brabec, Marek; Paulescu, M.; Badescu, V.

    2014-01-01

    Roč. 101, March (2014), s. 272-282 ISSN 0038-092X R&D Projects: GA MŠk LD12009 Grant - others:European Cooperation in Science and Technology(XE) COST ES1002 Institutional support: RVO:67985807 Keywords : sunshine number * nowcasting * generalized additive model * Markov chain Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 3.469, year: 2014

  20. Generalized data stacking programming model with applications

    OpenAIRE

    Hala Samir Elhadidy; Rawya Yehia Rizk; Hassen Taher Dorrah

    2016-01-01

    Recent researches have shown that, everywhere in various sciences the systems are following stacked-based stored change behavior when subjected to events or varying environments “on and above” their normal situations. This paper presents a generalized data stack programming (GDSP) model which is developed to describe the system changes under varying environment. These changes which are captured with different ways such as sensor reading are stored in matrices. Extraction algorithm and identif...

  1. A General Business Model for Marine Reserves

    Science.gov (United States)

    Sala, Enric; Costello, Christopher; Dougherty, Dawn; Heal, Geoffrey; Kelleher, Kieran; Murray, Jason H.; Rosenberg, Andrew A.; Sumaila, Rashid

    2013-01-01

    Marine reserves are an effective tool for protecting biodiversity locally, with potential economic benefits including enhancement of local fisheries, increased tourism, and maintenance of ecosystem services. However, fishing communities often fear short-term income losses associated with closures, and thus may oppose marine reserves. Here we review empirical data and develop bioeconomic models to show that the value of marine reserves (enhanced adjacent fishing + tourism) may often exceed the pre-reserve value, and that economic benefits can offset the costs in as little as five years. These results suggest the need for a new business model for creating and managing reserves, which could pay for themselves and turn a profit for stakeholder groups. Our model could be expanded to include ecosystem services and other benefits, and it provides a general framework to estimate costs and benefits of reserves and to develop such business models. PMID:23573192

  2. Management of COPD in general practice in Denmark--participating in an educational program substantially improves adherence to guidelines

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Hansen, Ejvind Frausing; Jensen, Michael Skov

    2010-01-01

    . DESIGN AND SETTING: Two cross-sectional surveys were performed precisely one year apart before and after an educational program for the participating GPs. A total of 124 GPs completed the study; 1716 and 1342 patients with GP-diagnosed COPD and no concomitant asthma, respectively, were included......BACKGROUND AND AIM: The general practitioner (GP) is the first contact with the health care system for most patients with COPD in Denmark. We studied, if participating in an educational program could improve adherence to guidelines, not least for diagnosis, staging, and treatment of the disease...... by focused education of GPs and their staff....

  3. Clinical practice guidelines and comorbid diseases: a MiniZinc representation of guideline models for mitigating adverse interactions.

    Science.gov (United States)

    Wilk, Szymon; Michalowski, Martin; Michalowski, Wojtek; Farion, Ken; Lin, Di; Hing, Marisela Mainegra; Mohapatra, Subhra

    2013-01-01

    Managing a patient with comorbid diseases according to multiple clinical practice guidelines (CPGs) may result in adverse interactions that need to be mitigated (identified and addressed) so a safe therapy can be devised. However, mitigation poses both clinical and methodological challenges. It requires extensive domain knowledge and calls for advanced CPG models and efficient algorithms to process them. We respond to the above challenges by describing our algorithm that mitigates interactions between pairs of CPGs. The algorithm creates logical models of analyzed CPGs and uses constraint logic programming (CLP) together with domain knowledge, codified as interaction and revision operators, to process them. Logical CPG models are transformed into CLP-CPG models that are solved to find a safe therapy. We represent these CLP-CPG models using MiniZinc, a standard language for CLP models. As motivation and illustration of our mitigation algorithm we use a clinical case study describing a patient managed for hypertension and deep vein thrombosis according to two individual CPGs. We apply the algorithm to this scenario and present MiniZinc representations of the constructed CLP-CPG models.

  4. 77 FR 27486 - Notice of Continuance for General Clearance for Guidelines, Applications and Reporting Forms

    Science.gov (United States)

    2012-05-10

    ... NATIONAL FOUNDATION FOR THE ARTS AND HUMANITIES Notice of Continuance for General Clearance for... Foundation for the Arts and Humanities. ACTION: Notice, request for comments, collection of information... Agencies, museums, libraries, institutions of higher education, library and museum professional...

  5. Understanding diagnosis and management of dementia and guideline implementation in general practice: a qualitative study using the theoretical domains framework.

    Science.gov (United States)

    Murphy, Kerry; O'Connor, Denise A; Browning, Colette J; French, Simon D; Michie, Susan; Francis, Jill J; Russell, Grant M; Workman, Barbara; Flicker, Leon; Eccles, Martin P; Green, Sally E

    2014-03-03

    Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs' reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of 'Beliefs about consequences'); discomfort in using validated tools ('Emotion'), possibly due to limited training and confidence ('Skills'; 'Beliefs about capabilities'); limited awareness of the need for, and forgetting to conduct, a depression assessment ('Knowledge'; 'Memory, attention and decision processes'). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment ('Knowledge'); possessing the necessary skills and confidence ('Skills'; 'Beliefs

  6. A generalized additive regression model for survival times

    DEFF Research Database (Denmark)

    Scheike, Thomas H.

    2001-01-01

    Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models......Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models...

  7. Generalized data stacking programming model with applications

    Directory of Open Access Journals (Sweden)

    Hala Samir Elhadidy

    2016-09-01

    Full Text Available Recent researches have shown that, everywhere in various sciences the systems are following stacked-based stored change behavior when subjected to events or varying environments “on and above” their normal situations. This paper presents a generalized data stack programming (GDSP model which is developed to describe the system changes under varying environment. These changes which are captured with different ways such as sensor reading are stored in matrices. Extraction algorithm and identification technique are proposed to extract the different layers between images and identify the stack class the object follows; respectively. The general multi-stacking network is presented including the interaction between various stack-based layering of some applications. The experiments prove that the concept of stack matrix gives average accuracy of 99.45%.

  8. Neuropathological assessment and validation of mouse models for Alzheimer's disease: applying NIA-AA guidelines

    Directory of Open Access Journals (Sweden)

    C. Dirk Keene

    2016-06-01

    Full Text Available Dozens of transgenic mouse models, generally based on mutations associated with familial Alzheimer's disease (AD, have been developed, in part, for preclinical testing of candidate AD therapies. However, none of these models has successfully predicted the clinical efficacy of drugs for treating AD patients. Therefore, development of more translationally relevant AD mouse models remains a critical unmet need in the field. A concept not previously implemented in AD preclinical drug testing is the use of mouse lines that have been validated for neuropathological features of human AD. Current thinking suggests that amyloid plaque and neurofibrillary tangle deposition is an essential component for accurate modeling of AD. Therefore, the AD translational paradigm would require pathologic Aβ and tau deposition, a disease-relevant distribution of plaques and tangles, and a pattern of disease progression of Aβ and tau isoforms similar to the neuropathological features found in the brains of AD patients. Additional parameters useful to evaluate parallels between AD and animal models would include 1 cerebrospinal fluid (CSF AD biomarker changes with reduced Aβ and increased phospho-tau/tau; 2 structural and functional neuroimaging patterns including MRI hippocampal atrophy, fluorodeoxyglucose (FDG, and amyloid/tau PET alterations in activity and/or patterns of pathologic peptide deposition and distribution; and 3 cognitive impairment with emphasis on spatial learning and memory to distinguish presymptomatic and symptomatic mice at specific ages. A validated AD mouse model for drug testing would likely show tau-related neurofibrillary degeneration following Aβ deposition and demonstrate changes in pathology, CSF analysis, and neuroimaging that mirror human AD. Development of the ideal model would revolutionize the ability to establish the translational value of AD mouse models and serve as a platform for discussions about national phenotyping guidelines

  9. [Summary of the practice guideline 'Pregnancy and puerperium' from the Dutch College of General Practitioners].

    Science.gov (United States)

    Wiersma, T J; Daemers, D O; Oldenziel, J H; Flikweert, S; Assendelft, W J

    2004-01-10

    During the first trimester of pregnancy, obstetric care concentrates particularly on assessment of gestational age (by history taking or if menstrual history is unclear, ultrasonography) and on the assessment of obstetric or medical risk factors necessitating a referral for specialist care. Tracing hereditary conditions in relatives is important as this is a reason for antenatal screening for congenital abnormalities. In comparison to the previous guideline, blood testing in the first trimester has been extended to include screening for irregular erythrocyte antibodies and the possibility of screening for HIV. Pregnant women with a history of thyroid problems may also be tested for serum concentrations of thyroid stimulating hormone (TSH), free T4 and, on indication, the TSH-receptor antibody levels. Since haemodilution is physiologically normal during the second half of pregnancy, at a gestational age of 18 weeks and above, only a haemoglobin-level of 6.5 mmol/l or less justifies the diagnosis of anaemia, and should treatment be commenced. If a newborn does not show any abnormalities immediately after delivery, the physical examination now routinely carried out at a few days post-partum rarely produces any additional findings and can safely be omitted.

  10. General guidelines for biomedical software development [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Luis Bastiao Silva

    2017-03-01

    Full Text Available Most bioinformatics tools available today were not written by professional software developers, but by people that wanted to solve their own problems, using computational solutions and spending the minimum time and effort possible, since these were just the means to an end. Consequently, a vast number of software applications are currently available, hindering the task of identifying the utility and quality of each. At the same time, this situation has hindered regular adoption of these tools in clinical practice. Typically, they are not sufficiently developed to be used by most clinical researchers and practitioners. To address these issues, it is necessary to re-think how biomedical applications are built and adopt new strategies that ensure quality, efficiency, robustness, correctness and reusability of software components. We also need to engage end-users during the development process to ensure that applications fit their needs. In this review, we present a set of guidelines to support biomedical software development, with an explanation of how they can be implemented and what kind of open-source tools can be used for each specific topic.

  11. General guidelines for biomedical software development [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Luis Bastiao Silva

    2017-07-01

    Full Text Available Most bioinformatics tools available today were not written by professional software developers, but by people that wanted to solve their own problems, using computational solutions and spending the minimum time and effort possible, since these were just the means to an end. Consequently, a vast number of software applications are currently available, hindering the task of identifying the utility and quality of each. At the same time, this situation has hindered regular adoption of these tools in clinical practice. Typically, they are not sufficiently developed to be used by most clinical researchers and practitioners. To address these issues, it is necessary to re-think how biomedical applications are built and adopt new strategies that ensure quality, efficiency, robustness, correctness and reusability of software components. We also need to engage end-users during the development process to ensure that applications fit their needs. In this review, we present a set of guidelines to support biomedical software development, with an explanation of how they can be implemented and what kind of open-source tools can be used for each specific topic.

  12. International peer reviews for radioactive waste management. General information and guidelines

    International Nuclear Information System (INIS)

    2005-01-01

    The NEA has an acknowledged role in developing a global strategy for examining the sustainability of the use of nuclear power and nuclear materials. One of the objectives of the NEA is to assist member countries in developing strategies for the safe, sustainable and broadly acceptable management of all types of radioactive waste, in particular long-lived waste and spent fuel. In this context, the Radioactive Waste Management Committee (RWMC) provides a forum for senior representatives from national agencies, regulatory authorities, policy making bodies, and research and development institutions with responsibilities in the management of radioactive waste and materials, as well as for other government-nominated specialists, to exchange information and experience on waste management policies and practices in NEA member countries, and to advance the state of the art on the technical and societal aspects of radioactive waste management. International peer reviews of national radioactive waste management programmes, or of specific aspects of them, have been increasingly carried out under the aegis of the RWMC over the past ten years. International peer review as a working method is closely associated with OECD practice, where it is facilitated by the homogeneous membership and the high degree of trust shared by the member countries. This document lays down the guidelines that the requesting country, the Secretariat and the international review team ought to have in mind when an international peer review is requested, organised or carried out. (author)

  13. Features and limitations of digital human models--a new German guideline.

    Science.gov (United States)

    Zülch, Gert

    2012-01-01

    In 2008 the Association of German Engineers (VDI) published the first part of the VDI 4499 guideline for methods and tools for the digital factory. Part 1 of this guideline deals with the fundamentals of the system and will be expanded by the addition of further parts on specific topics within the digital factory. Soon to be published is Part 4 which covers human models as tools of the digital factory. It describes the state of the art of current digital human models with regards to the methods and procedures implemented in German speaking countries. The structure of this part of the guideline is based on the different sections of engineering mechanics and outlines the opportunities for ergonomic assessments and the evaluation of work systems. During the writing of the guideline, the restrictions of the existing procedures also became evident thus showing the requirement for further development of such procedures. This is illustrated in this paper using examples from commercial software systems.

  14. Testing Parametric versus Semiparametric Modelling in Generalized Linear Models

    NARCIS (Netherlands)

    Härdle, W.K.; Mammen, E.; Müller, M.D.

    1996-01-01

    We consider a generalized partially linear model E(Y|X,T) = G{X'b + m(T)} where G is a known function, b is an unknown parameter vector, and m is an unknown function.The paper introduces a test statistic which allows to decide between a parametric and a semiparametric model: (i) m is linear, i.e.

  15. Modelling debris flows down general channels

    Directory of Open Access Journals (Sweden)

    S. P. Pudasaini

    2005-01-01

    Full Text Available This paper is an extension of the single-phase cohesionless dry granular avalanche model over curved and twisted channels proposed by Pudasaini and Hutter (2003. It is a generalisation of the Savage and Hutter (1989, 1991 equations based on simple channel topography to a two-phase fluid-solid mixture of debris material. Important terms emerging from the correct treatment of the kinematic and dynamic boundary condition, and the variable basal topography are systematically taken into account. For vanishing fluid contribution and torsion-free channel topography our new model equations exactly degenerate to the previous Savage-Hutter model equations while such a degeneration was not possible by the Iverson and Denlinger (2001 model, which, in fact, also aimed to extend the Savage and Hutter model. The model equations of this paper have been rigorously derived; they include the effects of the curvature and torsion of the topography, generally for arbitrarily curved and twisted channels of variable channel width. The equations are put into a standard conservative form of partial differential equations. From these one can easily infer the importance and influence of the pore-fluid-pressure distribution in debris flow dynamics. The solid-phase is modelled by applying a Coulomb dry friction law whereas the fluid phase is assumed to be an incompressible Newtonian fluid. Input parameters of the equations are the internal and bed friction angles of the solid particles, the viscosity and volume fraction of the fluid, the total mixture density and the pore pressure distribution of the fluid at the bed. Given the bed topography and initial geometry and the initial velocity profile of the debris mixture, the model equations are able to describe the dynamics of the depth profile and bed parallel depth-averaged velocity distribution from the initial position to the final deposit. A shock capturing, total variation diminishing numerical scheme is implemented to

  16. Prediction of lake surface temperature using the air2water model: guidelines, challenges, and future perspectives

    Directory of Open Access Journals (Sweden)

    Sebastiano Piccolroaz

    2016-04-01

    Full Text Available Water temperature plays a primary role in controlling a wide range of physical, geochemical and ecological processes in lakes, with considerable influences on lake water quality and ecosystem functioning. Being able to reliably predict water temperature is therefore a desired goal, which stimulated the development of models of different type and complexity, ranging from simple regression-based models to more sophisticated process-based numerical models. However, both types of models suffer of some limitations: the first are not able to address some fundamental physical processes as e.g., thermal stratification, while the latter generally require a large amount of data in input, which are not always available. In this work, lake surface temperature is simulated by means of air2water, a hybrid physically-based/statistical model, which is able to provide a robust, predictive understanding of LST dynamics knowing air temperature only. This model showed performances that are comparable with those obtained by using process based models (a root mean square error on the order of 1°C, at daily scale, while retaining the simplicity and parsimony of regression-based models, thus making it a good candidate for long-term applications.The aim of the present work is to provide the reader with useful and practical guidelines for proper use of the air2water model and for critical analysis of results. Two case studies have been selected for the analysis: Lake Superior and Lake Erie. These are clear and emblematic examples of a deep and a shallow temperate lake characterized by markedly different thermal responses to external forcing, thus are ideal for making the results of the analysis the most general and comprehensive. Particular attention is paid to assessing the influence of missing data on model performance, and to evaluating when an observed time series is sufficiently informative for proper model calibration or, conversely, data are too scarce thus

  17. Thurstonian models for sensory discrimination tests as generalized linear models

    DEFF Research Database (Denmark)

    Brockhoff, Per B.; Christensen, Rune Haubo Bojesen

    2010-01-01

    as a so-called generalized linear model. The underlying sensory difference 6 becomes directly a parameter of the statistical model and the estimate d' and it's standard error becomes the "usual" output of the statistical analysis. The d' for the monadic A-NOT A method is shown to appear as a standard...... linear contrast in a generalized linear model using the probit link function. All methods developed in the paper are implemented in our free R-package sensR (http://www.cran.r-project.org/package=sensR/). This includes the basic power and sample size calculations for these four discrimination tests...

  18. The Generalized Quantum Episodic Memory Model.

    Science.gov (United States)

    Trueblood, Jennifer S; Hemmer, Pernille

    2017-11-01

    Recent evidence suggests that experienced events are often mapped to too many episodic states, including those that are logically or experimentally incompatible with one another. For example, episodic over-distribution patterns show that the probability of accepting an item under different mutually exclusive conditions violates the disjunction rule. A related example, called subadditivity, occurs when the probability of accepting an item under mutually exclusive and exhaustive instruction conditions sums to a number >1. Both the over-distribution effect and subadditivity have been widely observed in item and source-memory paradigms. These phenomena are difficult to explain using standard memory frameworks, such as signal-detection theory. A dual-trace model called the over-distribution (OD) model (Brainerd & Reyna, 2008) can explain the episodic over-distribution effect, but not subadditivity. Our goal is to develop a model that can explain both effects. In this paper, we propose the Generalized Quantum Episodic Memory (GQEM) model, which extends the Quantum Episodic Memory (QEM) model developed by Brainerd, Wang, and Reyna (2013). We test GQEM by comparing it to the OD model using data from a novel item-memory experiment and a previously published source-memory experiment (Kellen, Singmann, & Klauer, 2014) examining the over-distribution effect. Using the best-fit parameters from the over-distribution experiments, we conclude by showing that the GQEM model can also account for subadditivity. Overall these results add to a growing body of evidence suggesting that quantum probability theory is a valuable tool in modeling recognition memory. Copyright © 2016 Cognitive Science Society, Inc.

  19. The epistemological status of general circulation models

    Science.gov (United States)

    Loehle, Craig

    2017-05-01

    Forecasts of both likely anthropogenic effects on climate and consequent effects on nature and society are based on large, complex software tools called general circulation models (GCMs). Forecasts generated by GCMs have been used extensively in policy decisions related to climate change. However, the relation between underlying physical theories and results produced by GCMs is unclear. In the case of GCMs, many discretizations and approximations are made, and simulating Earth system processes is far from simple and currently leads to some results with unknown energy balance implications. Statistical testing of GCM forecasts for degree of agreement with data would facilitate assessment of fitness for use. If model results need to be put on an anomaly basis due to model bias, then both visual and quantitative measures of model fit depend strongly on the reference period used for normalization, making testing problematic. Epistemology is here applied to problems of statistical inference during testing, the relationship between the underlying physics and the models, the epistemic meaning of ensemble statistics, problems of spatial and temporal scale, the existence or not of an unforced null for climate fluctuations, the meaning of existing uncertainty estimates, and other issues. Rigorous reasoning entails carefully quantifying levels of uncertainty.

  20. Generalized continuous linear model of international trade

    Directory of Open Access Journals (Sweden)

    Kostenko Elena

    2014-01-01

    Full Text Available The probability-based approach to the linear model of international trade based on the theory of Markov processes with continuous time is analysed. A generalized continuous model of international trade is built, in which the transition of the system from state to state is described by linear differential equations. The methodology of how to obtain the intensity matrices, which are differential in nature, is shown, and the same is done for their corresponding transition matrices for processes of purchasing and selling. In the process of the creation of the continuous model, functions and operations of matrices were used in addition to the Laplace transform, which gave the analytical form of the transition matrices, and therefore the expressions for the state vectors of the system. The obtained expressions simplify analysis and calculations in comparison to other methods. The values of the continuous transition matrices include in themselves the results of discrete model of international trade at moments in time proportional to the time step. The continuous model improves the quality of planning and the effectiveness of control of international trade agreements.

  1. The epistemological status of general circulation models

    Science.gov (United States)

    Loehle, Craig

    2018-03-01

    Forecasts of both likely anthropogenic effects on climate and consequent effects on nature and society are based on large, complex software tools called general circulation models (GCMs). Forecasts generated by GCMs have been used extensively in policy decisions related to climate change. However, the relation between underlying physical theories and results produced by GCMs is unclear. In the case of GCMs, many discretizations and approximations are made, and simulating Earth system processes is far from simple and currently leads to some results with unknown energy balance implications. Statistical testing of GCM forecasts for degree of agreement with data would facilitate assessment of fitness for use. If model results need to be put on an anomaly basis due to model bias, then both visual and quantitative measures of model fit depend strongly on the reference period used for normalization, making testing problematic. Epistemology is here applied to problems of statistical inference during testing, the relationship between the underlying physics and the models, the epistemic meaning of ensemble statistics, problems of spatial and temporal scale, the existence or not of an unforced null for climate fluctuations, the meaning of existing uncertainty estimates, and other issues. Rigorous reasoning entails carefully quantifying levels of uncertainty.

  2. Do general practices adhere to organizational guidelines for effective cervical cancer screening?

    NARCIS (Netherlands)

    Hermens, R P; Hak, E; Hulscher, M E; Mulder, J; Braspenning, J C; Grol, R P

    BACKGROUND: Well-organized cervical screening has been shown to be effective in the reduction of both morbidity and mortality from cancer of the uterine cervix. In The Netherlands, the GP plays an important role in the cervical screening. The question is whether the general practices are able to

  3. Basic Guidelines to Introduce Electric Circuit Simulation Software in a General Physics Course

    Science.gov (United States)

    Moya, A. A.

    2018-01-01

    The introduction of electric circuit simulation software for undergraduate students in a general physics course is proposed in order to contribute to the constructive learning of electric circuit theory. This work focuses on the lab exercises based on dc, transient and ac analysis in electric circuits found in introductory physics courses, and…

  4. Aspects of general linear modelling of migration.

    Science.gov (United States)

    Congdon, P

    1992-01-01

    "This paper investigates the application of general linear modelling principles to analysing migration flows between areas. Particular attention is paid to specifying the form of the regression and error components, and the nature of departures from Poisson randomness. Extensions to take account of spatial and temporal correlation are discussed as well as constrained estimation. The issue of specification bears on the testing of migration theories, and assessing the role migration plays in job and housing markets: the direction and significance of the effects of economic variates on migration depends on the specification of the statistical model. The application is in the context of migration in London and South East England in the 1970s and 1980s." excerpt

  5. Superconductivity in a generalized Hubbard model

    Science.gov (United States)

    Arrachea, Liliana; Aligia, A. A.

    1997-02-01

    We consider a Hubbard model in the square lattice, with a generalized hopping between nearest-neighbor sites for spin up (down), which depends on the total occupation nb of spin down (up) electrons on both sites. We call the hopping parameters tAA, tAB, and tBB for nb = 0, 1 or 2 respectively. Using the Hartree-Fock and Bardeen-Cooper-Schrieffer mean-field approximations to decouple the two-body and three-body interactions, we find that the model exhibits extended s-wave superconductivity in the electron-hole symmetric case tAB > tAA = tBB for small values of the Coulomb repulsion U or small band fillings. For moderate values of U, the antiferromagnetic normal (AFN) state has lower energy. The translationally invariant d-wave superconducting state has always larger energy than the AFN state.

  6. Functional methods in the generalized Dicke model

    International Nuclear Information System (INIS)

    Alcalde, M. Aparicio; Lemos, A.L.L. de; Svaiter, N.F.

    2007-01-01

    The Dicke model describes an ensemble of N identical two-level atoms (qubits) coupled to a single quantized mode of a bosonic field. The fermion Dicke model should be obtained by changing the atomic pseudo-spin operators by a linear combination of Fermi operators. The generalized fermion Dicke model is defined introducing different coupling constants between the single mode of the bosonic field and the reservoir, g 1 and g 2 for rotating and counter-rotating terms respectively. In the limit N -> ∞, the thermodynamic of the fermion Dicke model can be analyzed using the path integral approach with functional method. The system exhibits a second order phase transition from normal to superradiance at some critical temperature with the presence of a condensate. We evaluate the critical transition temperature and present the spectrum of the collective bosonic excitations for the general case (g 1 ≠ 0 and g 2 ≠ 0). There is quantum critical behavior when the coupling constants g 1 and g 2 satisfy g 1 + g 2 =(ω 0 Ω) 1/2 , where ω 0 is the frequency of the mode of the field and Ω is the energy gap between energy eigenstates of the qubits. Two particular situations are analyzed. First, we present the spectrum of the collective bosonic excitations, in the case g 1 ≠ 0 and g 2 ≠ 0, recovering the well known results. Second, the case g 1 ≠ 0 and g 2 ≠ 0 is studied. In this last case, it is possible to have a super radiant phase when only virtual processes are introduced in the interaction Hamiltonian. Here also appears a quantum phase transition at the critical coupling g 2 (ω 0 Ω) 1/2 , and for larger values for the critical coupling, the system enter in this super radiant phase with a Goldstone mode. (author)

  7. Chaos in generalized Jaynes-Cummings model

    Energy Technology Data Exchange (ETDEWEB)

    Chotorlishvili, L. [Institute for Physik, Martin-Luther-University Halle-Wittenberg, Heinrich-Damerow-Str. 4, 06120 Halle (Germany)], E-mail: lchotor33@yahoo.com; Toklikishvili, Z. [Physics Department of the Tbilisi State University, Chavchavadze av. 3, 0128 Tbilisi (Georgia)

    2008-04-14

    The possibility of chaos formation is studied in terms of a generalized Jaynes-Cummings model which is a key model in the quantum electrodynamics of resonators. In particular, the dynamics of a three-level optical atom which is under the action of the resonator field is considered. The specific feature of the considered problem consists in that not all transitions between the atom levels are permitted. This asymmetry of the system accounts for the complexity of the problem and makes it different from the three-level systems studied previously. We consider the most general case, where the interaction of the system with the resonator depends on the system coordinate inside the resonator. It is shown that, contrary to the commonly accepted opinion, the absence of resonance detuning does not guarantee the system state controllability. In the course of evolution the system performs an irreversible transition from the purely quantum-mechanical state to the mixed state. It is shown that the asymmetry of the system levels accounts for the fact that the upper excited level turns out to be the most populated one.

  8. A multifaceted implementation strategy versus passive implementation of low back pain guidelines in general practice: a cluster randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Allan Riis

    2016-10-01

    Full Text Available Abstract Background Guidelines are often slowly adapted into clinical practice. However, actively supporting healthcare professionals in evidence-based treatment may speed up guideline implementation. Danish low back pain (LBP guidelines focus on primary care treatment of LBP, to reduce referrals from primary care to secondary care. The primary aim of this project was to reduce secondary care referral within 12 weeks by a multifaceted implementation strategy (MuIS. Methods In a cluster randomised design, 189 general practices from the North Denmark Region were invited to participate. Practices were randomised (1:1 and stratified by practice size to MuIS (28 practices or a passive implementation strategy (PaIS; 32 practices. Included were patients with LBP aged 18 to 65 years who were able to complete questionnaires, had no serious underlying pathology, and were not pregnant. We developed a MuIS including outreach visits, quality reports, and the STarT Back Tool for subgrouping patients with LBP. Both groups were offered the usual dissemination of guidelines, guideline-concordant structuring of the medical record, and a new referral opportunity for patients with psycho-social problems. In an intention-to-treat analysis, the primary and secondary outcomes pertained to the patient, and a cost-effectiveness analysis was performed from a healthcare sector perspective. Patients and the assessment of outcomes were blinded. Practices and caregivers delivering the interventions were not blinded. Results Between January 2013 and July 2014, 60 practices were included, of which 54 practices (28 MuIS, 26 PaIS included 1101 patients (539 MuIS, 562 PaIS. Follow-up data for the primary outcome were available on 100 % of these patients. Twenty-seven patients (5.0 % in the MuIS group were referred to secondary care vs. 59 patients (10.5 % in the PaIS group. The adjusted odds ratio (AOR was 0.52 [95 % CI 0.30 to 0.90; p = 0.020]. The MuIS was cost

  9. Basic guidelines to introduce electric circuit simulation software in a general physics course

    Science.gov (United States)

    Moya, A. A.

    2018-05-01

    The introduction of electric circuit simulation software for undergraduate students in a general physics course is proposed in order to contribute to the constructive learning of electric circuit theory. This work focuses on the lab exercises based on dc, transient and ac analysis in electric circuits found in introductory physics courses, and shows how students can use the simulation software to do simple activities associated with a lab exercise itself and with related topics. By introducing electric circuit simulation programs in a general physics course as a brief activitiy complementing lab exercise, students develop basic skills in using simulation software, improve their knowledge on the topology of electric circuits and perceive that the technology contributes to their learning, all without reducing the time spent on the actual content of the course.

  10. Guidelines for visualizing and annotating rule-based models.

    Science.gov (United States)

    Chylek, Lily A; Hu, Bin; Blinov, Michael L; Emonet, Thierry; Faeder, James R; Goldstein, Byron; Gutenkunst, Ryan N; Haugh, Jason M; Lipniacki, Tomasz; Posner, Richard G; Yang, Jin; Hlavacek, William S

    2011-10-01

    Rule-based modeling provides a means to represent cell signaling systems in a way that captures site-specific details of molecular interactions. For rule-based models to be more widely understood and (re)used, conventions for model visualization and annotation are needed. We have developed the concepts of an extended contact map and a model guide for illustrating and annotating rule-based models. An extended contact map represents the scope of a model by providing an illustration of each molecule, molecular component, direct physical interaction, post-translational modification, and enzyme-substrate relationship considered in a model. A map can also illustrate allosteric effects, structural relationships among molecular components, and compartmental locations of molecules. A model guide associates elements of a contact map with annotation and elements of an underlying model, which may be fully or partially specified. A guide can also serve to document the biological knowledge upon which a model is based. We provide examples of a map and guide for a published rule-based model that characterizes early events in IgE receptor (FcεRI) signaling. We also provide examples of how to visualize a variety of processes that are common in cell signaling systems but not considered in the example model, such as ubiquitination. An extended contact map and an associated guide can document knowledge of a cell signaling system in a form that is visual as well as executable. As a tool for model annotation, a map and guide can communicate the content of a model clearly and with precision, even for large models.

  11. Customer-centered careflow modeling based on guidelines.

    Science.gov (United States)

    Huang, Biqing; Zhu, Peng; Wu, Cheng

    2012-10-01

    In contemporary society, customer-centered health care, which stresses customer participation and long-term tailored care, is inevitably becoming a trend. Compared with the hospital or physician-centered healthcare process, the customer-centered healthcare process requires more knowledge and modeling such a process is extremely complex. Thus, building a care process model for a special customer is cost prohibitive. In addition, during the execution of a care process model, the information system should have flexibility to modify the model so that it adapts to changes in the healthcare process. Therefore, supporting the process in a flexible, cost-effective way is a key challenge for information technology. To meet this challenge, first, we analyze various kinds of knowledge used in process modeling, illustrate their characteristics, and detail their roles and effects in careflow modeling. Secondly, we propose a methodology to manage a lifecycle of the healthcare process modeling, with which models could be built gradually with convenience and efficiency. In this lifecycle, different levels of process models are established based on the kinds of knowledge involved, and the diffusion strategy of these process models is designed. Thirdly, architecture and prototype of the system supporting the process modeling and its lifecycle are given. This careflow system also considers the compatibility of legacy systems and authority problems. Finally, an example is provided to demonstrate implementation of the careflow system.

  12. A general phenomenological model for work function

    Science.gov (United States)

    Brodie, I.; Chou, S. H.; Yuan, H.

    2014-07-01

    A general phenomenological model is presented for obtaining the zero Kelvin work function of any crystal facet of metals and semiconductors, both clean and covered with a monolayer of electropositive atoms. It utilizes the known physical structure of the crystal and the Fermi energy of the two-dimensional electron gas assumed to form on the surface. A key parameter is the number of electrons donated to the surface electron gas per surface lattice site or adsorbed atom, which is taken to be an integer. Initially this is found by trial and later justified by examining the state of the valence electrons of the relevant atoms. In the case of adsorbed monolayers of electropositive atoms a satisfactory justification could not always be found, particularly for cesium, but a trial value always predicted work functions close to the experimental values. The model can also predict the variation of work function with temperature for clean crystal facets. The model is applied to various crystal faces of tungsten, aluminium, silver, and select metal oxides, and most demonstrate good fits compared to available experimental values.

  13. A general model of learning design objects

    Directory of Open Access Journals (Sweden)

    Azeddine Chikh

    2014-01-01

    Full Text Available Previous research on the development of learning objects has targeted either learners, as consumers of these objects, or instructors, as designers who reuse these objects in building new online courses. There is currently an urgent need for the sharing and reuse of both theoretical knowledge (literature reviews and practical knowledge (best practice in learning design. The primary aim of this paper is to develop a strategy for constructing a more powerful set of learning objects targeted at supporting instructors in designing their curricula. A key challenge in this work is the definition of a new class of learning design objects that combine two types of knowledge: (1 reusable knowledge, consisting of theoretical and practical information on education design, and (2 knowledge of reuse, which is necessary to describe the reusable knowledge using an extended learning object metadata language. In addition, we introduce a general model of learning design object repositories based on the Unified Modeling Language, and a learning design support framework is proposed based on the repository model. Finally, a first prototype is developed to provide a subjective evaluation of the new framework.

  14. A pattern-based analysis of clinical computer-interpretable guideline modeling languages.

    Science.gov (United States)

    Mulyar, Nataliya; van der Aalst, Wil M P; Peleg, Mor

    2007-01-01

    Languages used to specify computer-interpretable guidelines (CIGs) differ in their approaches to addressing particular modeling challenges. The main goals of this article are: (1) to examine the expressive power of CIG modeling languages, and (2) to define the differences, from the control-flow perspective, between process languages in workflow management systems and modeling languages used to design clinical guidelines. The pattern-based analysis was applied to guideline modeling languages Asbru, EON, GLIF, and PROforma. We focused on control-flow and left other perspectives out of consideration. We evaluated the selected CIG modeling languages and identified their degree of support of 43 control-flow patterns. We used a set of explicitly defined evaluation criteria to determine whether each pattern is supported directly, indirectly, or not at all. PROforma offers direct support for 22 of 43 patterns, Asbru 20, GLIF 17, and EON 11. All four directly support basic control-flow patterns, cancellation patterns, and some advance branching and synchronization patterns. None support multiple instances patterns. They offer varying levels of support for synchronizing merge patterns and state-based patterns. Some support a few scenarios not covered by the 43 control-flow patterns. CIG modeling languages are remarkably close to traditional workflow languages from the control-flow perspective, but cover many fewer workflow patterns. CIG languages offer some flexibility that supports modeling of complex decisions and provide ways for modeling some decisions not covered by workflow management systems. Workflow management systems may be suitable for clinical guideline applications.

  15. Guidelines for developing and updating Bayesian belief networks applied to ecological modeling and conservation.

    Science.gov (United States)

    B.G. Marcot; J.D. Steventon; G.D. Sutherland; R.K. McCann

    2006-01-01

    We provide practical guidelines for developing, testing, and revising Bayesian belief networks (BBNs). Primary steps in this process include creating influence diagrams of the hypothesized "causal web" of key factors affecting a species or ecological outcome of interest; developing a first, alpha-level BBN model from the influence diagram; revising the model...

  16. Symplectic models for general insertion devices

    International Nuclear Information System (INIS)

    Wu, Y.; Forest, E.; Robin, D. S.; Nishimura, H.; Wolski, A.; Litvinenko, V. N.

    2001-01-01

    A variety of insertion devices (IDs), wigglers and undulators, linearly or elliptically polarized,are widely used as high brightness radiation sources at the modern light source rings. Long and high-field wigglers have also been proposed as the main source of radiation damping at next generation damping rings. As a result, it becomes increasingly important to understand the impact of IDs on the charged particle dynamics in the storage ring. In this paper, we report our recent development of a general explicit symplectic model for IDs with the paraxial ray approximation. High-order explicit symplectic integrators are developed to study real-world insertion devices with a number of wiggler harmonics and arbitrary polarizations

  17. New model for nucleon generalized parton distributions

    Energy Technology Data Exchange (ETDEWEB)

    Radyushkin, Anatoly V. [JLAB, Newport News, VA (United States)

    2014-01-01

    We describe a new type of models for nucleon generalized parton distributions (GPDs) H and E. They are heavily based on the fact nucleon GPDs require to use two forms of double distribution (DD) representations. The outcome of the new treatment is that the usual DD+D-term construction should be amended by an extra term, {xi} E{sub +}{sup 1} (x,{xi}) which has the DD structure {alpha}/{beta} e({beta},{alpha}, with e({beta},{alpha}) being the DD that generates GPD E(x,{xi}). We found that this function, unlike the D-term, has support in the whole -1 <= x <= 1 region. Furthermore, it does not vanish at the border points |x|={xi}.

  18. BSACI guidelines for the investigation of suspected anaphylaxis during general anaesthesia.

    Science.gov (United States)

    Ewan, P W; Dugué, P; Mirakian, R; Dixon, T A; Harper, J N; Nasser, S M

    2010-01-01

    Investigation of anaphylaxis during general anaesthesia requires an accurate record of events including information on timing of drug administration provided by the anaesthetist, as well as timed acute tryptase measurements. Referrals should be made to a centre with the experience and ability to investigate reactions to a range of drug classes/substances including neuromuscular blocking agents (NMBAs) intravenous (i.v.) anaesthetics, antibiotics, opioid analgesics, non-steroidal anti-inflammatory drugs (NSAIDs), local anaesthetics, colloids, latex and other agents. About a third of cases are due to allergy to NMBAs. Therefore, investigation should be carried out in a dedicated drug allergy clinic to allow seamless investigation of all suspected drug classes as a single day-case. This will often require skin prick tests, intra-dermal testing and/or drug challenge. Investigation must cover the agents administered, but should also include most other commonly used NMBAs and i.v. anaesthetics. The outcome should be to identify the cause and a range of drugs/agents likely to be safe for future use. The allergist is responsible for a detailed report to the referring anaesthetist and to the patient's GP as well as the surgeon/obstetrician. A shorter report should be provided to the patient, adding an allergy alert to the case notes and providing an application form for an alert-bracelet indicating the wording to be inscribed. The MHRA should be notified. Investigation of anaphylaxis during general anaesthesia should be focussed in major allergy centres with a high throughput of cases and with experience and ability as described above. We suggest this focus since there is a distinct lack of validated data for testing, thus requiring experience in interpreting tests and because of the serious consequences of diagnostic error.

  19. A Simple General Model of Evolutionary Dynamics

    Science.gov (United States)

    Thurner, Stefan

    Evolution is a process in which some variations that emerge within a population (of, e.g., biological species or industrial goods) get selected, survive, and proliferate, whereas others vanish. Survival probability, proliferation, or production rates are associated with the "fitness" of a particular variation. We argue that the notion of fitness is an a posteriori concept in the sense that one can assign higher fitness to species or goods that survive but one can generally not derive or predict fitness per se. Whereas proliferation rates can be measured, fitness landscapes, that is, the inter-dependence of proliferation rates, cannot. For this reason we think that in a physical theory of evolution such notions should be avoided. Here we review a recent quantitative formulation of evolutionary dynamics that provides a framework for the co-evolution of species and their fitness landscapes (Thurner et al., 2010, Physica A 389, 747; Thurner et al., 2010, New J. Phys. 12, 075029; Klimek et al., 2009, Phys. Rev. E 82, 011901 (2010). The corresponding model leads to a generic evolutionary dynamics characterized by phases of relative stability in terms of diversity, followed by phases of massive restructuring. These dynamical modes can be interpreted as punctuated equilibria in biology, or Schumpeterian business cycles (Schumpeter, 1939, Business Cycles, McGraw-Hill, London) in economics. We show that phase transitions that separate phases of high and low diversity can be approximated surprisingly well by mean-field methods. We demonstrate that the mathematical framework is suited to understand systemic properties of evolutionary systems, such as their proneness to collapse, or their potential for diversification. The framework suggests that evolutionary processes are naturally linked to self-organized criticality and to properties of production matrices, such as their eigenvalue spectra. Even though the model is phrased in general terms it is also practical in the sense

  20. Interconnection Guidelines

    Science.gov (United States)

    The Interconnection Guidelines provide general guidance on the steps involved with connecting biogas recovery systems to the utility electrical power grid. Interconnection best practices including time and cost estimates are discussed.

  1. Implementing referral guidelines: lessons from a negative outcome cluster randomised factorial trial in general practice

    Directory of Open Access Journals (Sweden)

    Shaw Lindsey

    2006-11-01

    Full Text Available Abstract Background Few patients with lower bowel symptoms who consult their general practitioner need a specialist opinion. However data from referred patients suggest that those who are referred would benefit from detailed assessment before referral. Methods A cluster randomised factorial trial. 44 general practices in North Trent, UK. Practices were offered either an electronic interactive referral pro forma, an educational outreach visit by a local colorectal surgeon, both or neither. The main outcome measure was the proportion of cases with severe diverticular disease, cancer or precancerous lesions and inflammatory bowel disease in those referred by each group. A secondary outcome was a referral letter quality score. Semi-structured interviews were conducted to identify key themes relating to the use of the software Results From 150 invitations, 44 practices were recruited with a total list size of 265,707. There were 716 consecutive referrals recorded over a six-month period, for which a diagnosis was available for 514. In the combined software arms 14% (37/261 had significant pathology, compared with 19% (49/253 in the non-software arms, relative risk 0.73 (95% CI: 0.46 to 1.15. In the combined educational outreach arms 15% (38/258 had significant pathology compared with 19% (48/256 in the non-educational arms, relative risk 0.79 (95% CI: 0.50 to 1.24. Pro forma practices documented better assessment of patients at referral. Conclusion There was a lack of evidence that either intervention increased the proportion of patients with organic pathology among those referred. The interactive software did improve the amount of information relayed in referral letters although we were unable to confirm if this made a significant difference to patients or their health care providers. The potential value of either intervention may have been diminished by their limited uptake within the context of a cluster randomised clinical trial. A number of

  2. MODEL OF BRAZILIAN URBANIZATION: GENERAL NOTES

    Directory of Open Access Journals (Sweden)

    Leandro da Silva Guimarães

    2016-07-01

    Full Text Available The full text format seeks to analyze the social inequality in Brazil through the spatial process of that inequality in this sense it analyzes, scratching the edges of what is known of the Brazilian urbanization model and how this same model produced gentrification cities and exclusive. So search the text discuss the country’s urban exclusion through consolidation of what is conventionally called peripheral areas, or more generally, of peripheries. The text on screen is the result of research carried out at the Federal Fluminense University in Masters level. In this study, we tried to understand the genesis of an urban housing development located in São Gonçalo, Rio de Janeiro called Jardim Catarina. Understand what the problem space partner who originated it. In this sense, his analysis becomes consubstantial to understand the social and spatial inequalities in Brazil, as well as the role of the state as planning manager socio-spatial planning and principal agent in the solution of such problems. It is expected that with the realization of a study of greater amounts, from which this article is just a micro work can contribute subsidies that contribute to the arrangement and crystallization of public policies that give account of social inequalities and serve to leverage a country more fair and equitable cities.

  3. [The practice guideline 'Vaginal discharge' (first revision) from the Dutch College of General Practitioners; a response from the perspective of gynaecology].

    Science.gov (United States)

    Hogewoning, C J A; Ottervanger, H P; Adriaanse, A H; Trum, J W

    2007-06-16

    The Dutch College of General Practitioners (NHG) revised their practice guideline on vaginal discharge. From a gynaecological point of view, relocation of cervix problems from this guideline to the NHG guideline 'The STD consultation' is not practical. Moreover, the role of simple, but effective diagnosis with a microscope in the primary-care setting cannot be overemphasized. The reluctance to oral treatment is rather inopportune, because once-only ingestion has the advantage of promoting compliance. As physical examination is not always necessary in a recurrent Candida infection, treatment performed by the patient with imidazole compounds is a possibility that does not always result in abuse or increased resistance.

  4. General single phase wellbore flow model

    Energy Technology Data Exchange (ETDEWEB)

    Ouyang, Liang-Biao; Arbabi, S.; Aziz, K.

    1997-02-05

    A general wellbore flow model, which incorporates not only frictional, accelerational and gravitational pressure drops, but also the pressure drop caused by inflow, is presented in this report. The new wellbore model is readily applicable to any wellbore perforation patterns and well completions, and can be easily incorporated in reservoir simulators or analytical reservoir inflow models. Three dimensionless numbers, the accelerational to frictional pressure gradient ratio R{sub af}, the gravitational to frictional pressure gradient ratio R{sub gf}, and the inflow-directional to accelerational pressure gradient ratio R{sub da}, have been introduced to quantitatively describe the relative importance of different pressure gradient components. For fluid flow in a production well, it is expected that there may exist up to three different regions of the wellbore: the laminar flow region, the partially-developed turbulent flow region, and the fully-developed turbulent flow region. The laminar flow region is located near the well toe, the partially-turbulent flow region lies in the middle of the wellbore, while the fully-developed turbulent flow region is at the downstream end or the heel of the wellbore. Length of each region depends on fluid properties, wellbore geometry and flow rate. As the distance from the well toe increases, flow rate in the wellbore increases and the ratios R{sub af} and R{sub da} decrease. Consequently accelerational and inflow-directional pressure drops have the greatest impact in the toe region of the wellbore. Near the well heel the local wellbore flow rate becomes large and close to the total well production rate, here R{sub af} and R{sub da} are small, therefore, both the accelerational and inflow-directional pressure drops can be neglected.

  5. Evaluating the double Poisson generalized linear model.

    Science.gov (United States)

    Zou, Yaotian; Geedipally, Srinivas Reddy; Lord, Dominique

    2013-10-01

    The objectives of this study are to: (1) examine the applicability of the double Poisson (DP) generalized linear model (GLM) for analyzing motor vehicle crash data characterized by over- and under-dispersion and (2) compare the performance of the DP GLM with the Conway-Maxwell-Poisson (COM-Poisson) GLM in terms of goodness-of-fit and theoretical soundness. The DP distribution has seldom been investigated and applied since its first introduction two decades ago. The hurdle for applying the DP is related to its normalizing constant (or multiplicative constant) which is not available in closed form. This study proposed a new method to approximate the normalizing constant of the DP with high accuracy and reliability. The DP GLM and COM-Poisson GLM were developed using two observed over-dispersed datasets and one observed under-dispersed dataset. The modeling results indicate that the DP GLM with its normalizing constant approximated by the new method can handle crash data characterized by over- and under-dispersion. Its performance is comparable to the COM-Poisson GLM in terms of goodness-of-fit (GOF), although COM-Poisson GLM provides a slightly better fit. For the over-dispersed data, the DP GLM performs similar to the NB GLM. Considering the fact that the DP GLM can be easily estimated with inexpensive computation and that it is simpler to interpret coefficients, it offers a flexible and efficient alternative for researchers to model count data. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. A Note on the Identifiability of Generalized Linear Mixed Models

    DEFF Research Database (Denmark)

    Labouriau, Rodrigo

    2014-01-01

    I present here a simple proof that, under general regularity conditions, the standard parametrization of generalized linear mixed model is identifiable. The proof is based on the assumptions of generalized linear mixed models on the first and second order moments and some general mild regularity ...... conditions, and, therefore, is extensible to quasi-likelihood based generalized linear models. In particular, binomial and Poisson mixed models with dispersion parameter are identifiable when equipped with the standard parametrization...

  7. ASGW Best Practice Guidelines: An Evaluation of the Duluth Model

    Science.gov (United States)

    Pender, Rebecca L.

    2012-01-01

    Group work is often a preferred method of intervention when treating perpetrators of domestic violence. The Domestic Abuse Intervention Project Duluth Model is one of the most common treatment programs for men who have perpetrated domestic violence (Pence & Paymar, 2003), yet the intervention remains highly debated within the literature. This…

  8. A model of facilitative communication for support of general hospital nurses nursing mentally ill people

    Directory of Open Access Journals (Sweden)

    TR Mavundla

    2001-09-01

    Full Text Available Part 1 of this article dealt with a full description of the research design and methods. This article aims at describing a model of facilitative communication to support general hospital nurses nursing the mentally-ill. In this article a model of facilitative communication applicable to any general hospital setting is proposed. Fundamental assumptions and relationship statements are highlighted and the structure and process of facilitative communication is described according to the three steps employed: 1 assisting the general hospital nurse learn the skill; 2 assisting the general hospital nurse practise the skill in order to develop confidence; and 3 using the skill in a work setting. The guidelines for operationalising this model are dealt with in the next article. The evaluation of the model is also briefly described.

  9. Bayesian Subset Modeling for High-Dimensional Generalized Linear Models

    KAUST Repository

    Liang, Faming

    2013-06-01

    This article presents a new prior setting for high-dimensional generalized linear models, which leads to a Bayesian subset regression (BSR) with the maximum a posteriori model approximately equivalent to the minimum extended Bayesian information criterion model. The consistency of the resulting posterior is established under mild conditions. Further, a variable screening procedure is proposed based on the marginal inclusion probability, which shares the same properties of sure screening and consistency with the existing sure independence screening (SIS) and iterative sure independence screening (ISIS) procedures. However, since the proposed procedure makes use of joint information from all predictors, it generally outperforms SIS and ISIS in real applications. This article also makes extensive comparisons of BSR with the popular penalized likelihood methods, including Lasso, elastic net, SIS, and ISIS. The numerical results indicate that BSR can generally outperform the penalized likelihood methods. The models selected by BSR tend to be sparser and, more importantly, of higher prediction ability. In addition, the performance of the penalized likelihood methods tends to deteriorate as the number of predictors increases, while this is not significant for BSR. Supplementary materials for this article are available online. © 2013 American Statistical Association.

  10. Multivariate generalized linear model for genetic pleiotropy.

    Science.gov (United States)

    Schaid, Daniel J; Tong, Xingwei; Batzler, Anthony; Sinnwell, Jason P; Qing, Jiang; Biernacka, Joanna M

    2017-12-16

    When a single gene influences more than one trait, known as pleiotropy, it is important to detect pleiotropy to improve the biological understanding of a gene. This can lead to improved screening, diagnosis, and treatment of diseases. Yet, most current multivariate methods to evaluate pleiotropy test the null hypothesis that none of the traits are associated with a variant; departures from the null could be driven by just one associated trait. A formal test of pleiotropy should assume a null hypothesis that one or fewer traits are associated with a genetic variant. We recently developed statistical methods to analyze pleiotropy for quantitative traits having a multivariate normal distribution. We now extend this approach to traits that can be modeled by generalized linear models, such as analysis of binary, ordinal, or quantitative traits, or a mixture of these types of traits. Based on methods from estimating equations, we developed a new test for pleiotropy. We then extended the testing framework to a sequential approach to test the null hypothesis that $k+1$ traits are associated, given that the null of $k$ associated traits was rejected. This provides a testing framework to determine the number of traits associated with a genetic variant, as well as which traits, while accounting for correlations among the traits. By simulations, we illustrate the Type-I error rate and power of our new methods, describe how they are influenced by sample size, the number of traits, and the trait correlations, and apply the new methods to a genome-wide association study of multivariate traits measuring symptoms of major depression. Our new approach provides a quantitative assessment of pleiotropy, enhancing current analytic practice. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Guidelines for effective radiation transport for cable SGEMP modeling

    Energy Technology Data Exchange (ETDEWEB)

    Drumm, Clifton Russell [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fan, Wesley C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Turner, C. David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-07-01

    This report describes experiences gained in performing radiation transport computations with the SCEPTRE radiation transport code for System Generated ElectroMagnetic Pulse (SGEMP) applications. SCEPTRE is a complex code requiring a fairly sophisticated user to run the code effectively, so this report provides guidance for analysts interested in performing these types of calculations. One challenge in modeling coupled photon/electron transport for SGEMP is to provide a spatial mesh that is sufficiently resolved to accurately model surface charge emission and charge deposition near material interfaces. The method that has been most commonly used to date to compute cable SGEMP typically requires a sub-micron mesh size near material interfaces, which may be difficult for meshing software to provide for complex geometries. We present here an alternative method for computing cable SGEMP that appears to substantially relax this requirement. The report also investigates the effect of refining the energy mesh and increasing the order of the angular approximation to provide some guidance on determining reasonable parameters for the energy/angular approximation needed for x-ray environments. Conclusions for γ-ray environments may be quite different and will be treated in a subsequent report. In the course of the energy-mesh refinement studies, a bug in the cross-section generation software was discovered that may cause underprediction of the result by as much as an order of magnitude for the test problem studied here, when the electron energy group widths are much smaller than those for the photons. Results will be presented and compared using cross sections generated before and after the fix. We also describe adjoint modeling, which provides sensitivity of the total charge drive to the source energy and angle of incidence, which is quite useful for comparing the effect of changing the source environment and for determining most stressing angle of incidence and source

  12. A generalized model for homogenized reflectors

    International Nuclear Information System (INIS)

    Pogosbekyan, Leonid; Kim, Yeong Il; Kim, Young Jin; Joo, Hyung Kook

    1996-01-01

    A new concept of equivalent homogenization is proposed. The concept employs new set of homogenized parameters: homogenized cross sections (XS) and interface matrix (IM), which relates partial currents at the cell interfaces. The idea of interface matrix generalizes the idea of discontinuity factors (DFs), proposed and developed by K. Koebke and K. Smith. The method of K. Smith can be simulated within framework of new method, while the new method approximates hetero-geneous cell better in case of the steep flux gradients at the cell interfaces. The attractive shapes of new concept are:improved accuracy, simplicity of incorporation in the existing codes, equal numerical expenses in comparison to the K. Smith's approach. The new concept is useful for: (a) explicit reflector/baffle simulation; (b)control blades simulation; (c) mixed UO 2 /MOX core simulation. The offered model has been incorporated in the finite difference code and in the nodal code PANBOX. The numerical results show good accuracy of core calculations and insensitivity of homogenized parameters with respect to in-core conditions

  13. Cosmological models in the generalized Einstein action

    International Nuclear Information System (INIS)

    Arbab, A.I.

    2007-12-01

    We have studied the evolution of the Universe in the generalized Einstein action of the form R + β R 2 , where R is the scalar curvature and β = const. We have found exact cosmological solutions that predict the present cosmic acceleration. These models predict an inflationary de-Sitter era occurring in the early Universe. The cosmological constant (Λ) is found to decay with the Hubble constant (H) as, Λ ∝ H 4 . In this scenario the cosmological constant varies quadratically with the energy density (ρ), i.e., Λ ∝ ρ 2 . Such a variation is found to describe a two-component cosmic fluid in the Universe. One of the components accelerated the Universe in the early era, and the other in the present era. The scale factor of the Universe varies as a ∼ t n = 1/2 in the radiation era. The cosmological constant vanishes when n = 4/3 and n =1/2. We have found that the inclusion of the term R 2 mimics a cosmic matter that could substitute the ordinary matter. (author)

  14. Climatology of the HOPE-G global ocean general circulation model - Sea ice general circulation model

    Energy Technology Data Exchange (ETDEWEB)

    Legutke, S. [Deutsches Klimarechenzentrum (DKRZ), Hamburg (Germany); Maier-Reimer, E. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

    1999-12-01

    The HOPE-G global ocean general circulation model (OGCM) climatology, obtained in a long-term forced integration is described. HOPE-G is a primitive-equation z-level ocean model which contains a dynamic-thermodynamic sea-ice model. It is formulated on a 2.8 grid with increased resolution in low latitudes in order to better resolve equatorial dynamics. The vertical resolution is 20 layers. The purpose of the integration was both to investigate the models ability to reproduce the observed general circulation of the world ocean and to obtain an initial state for coupled atmosphere - ocean - sea-ice climate simulations. The model was driven with daily mean data of a 15-year integration of the atmosphere general circulation model ECHAM4, the atmospheric component in later coupled runs. Thereby, a maximum of the flux variability that is expected to appear in coupled simulations is included already in the ocean spin-up experiment described here. The model was run for more than 2000 years until a quasi-steady state was achieved. It reproduces the major current systems and the main features of the so-called conveyor belt circulation. The observed distribution of water masses is reproduced reasonably well, although with a saline bias in the intermediate water masses and a warm bias in the deep and bottom water of the Atlantic and Indian Oceans. The model underestimates the meridional transport of heat in the Atlantic Ocean. The simulated heat transport in the other basins, though, is in good agreement with observations. (orig.)

  15. Application of Improved Radiation Modeling to General Circulation Models

    Energy Technology Data Exchange (ETDEWEB)

    Michael J Iacono

    2011-04-07

    This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.

  16. Re-using a Knowledge Base in Different Guideline Models: Experience in PRODIGY

    Science.gov (United States)

    Hall, Richard W; Jones, Neill; Purves, Ian

    2002-01-01

    One of the main considerations of groups who develop guideline-based decision support systems is how to reuse a knowledge base across different guideline models. Without significant reuse, knowledge bases often have to be constructed virtually from scratch, resulting in vast duplication of effort and wastage of resource. We have successfully demonstrated a method within PRODIGY for migrating the current Release One knowledge base - designed for use within legacy computer systems - into a new knowledge base, the basis of a system designed to run on ‘state-of-the-art’ computer systems.

  17. Suspected cow's milk allergy in everyday general practice: a retrospective cohort study on health care burden and guideline adherence.

    Science.gov (United States)

    van den Hoogen, Sharayke C T A; van de Pol, Alma C; Meijer, Yolanda; Toet, Jaap; van Klei, Céline; de Wit, Niek J

    2014-08-09

    Cow's milk allergy (CMA) is the most common food allergy among infants. No data are available on the health care burden of suspected CMA in general practice. This study was conducted to evaluate the burden of suspected CMA in general practice (GP): (a) prevalence, (b) presenting symptoms, (c) diagnostic process, (d) guideline adherence, and (e) dietary measures. A retrospective cohort study was carried out in four Julius Healthcare Centers (JHCs). These JHCs form the core primary care academic network of the department of general practice of the University Medical Center of Utrecht. Electronic records of the first year of infants born May 2009 - April 2010 registered in the JHCs were screened for possible CMA suspicion. Preventive child healthcare (PCH) records were reviewed for additional information. Clinical presentation, diagnostic strategies and dietary measures were extracted. Of 804 infants evaluated, 55 presented with symptoms fitting the suspicion of CMA (prevalence of 7%). Presenting complaints involved the skin (71%); the gastrointestinal tract (60%); the respiratory tract (13%) or other symptoms (36%) and 23 infants presented with symptoms of two or more organ systems. In 31 children (56%) a food challenge was performed (n = 28 open and n = 3 double-blind). Open challenge test results were difficult to interpret due to inadequate implementation or reporting. None had confirmed CMA after an adequate challenge test. Long term milk substitute formulas were prescribed in 39 (71%) infants. On a yearly basis seven percent of children visit their GP for suspected CMA. A positive CMA diagnosis was rarely established after adequate implementation and reporting of diagnostics, yet long term dietary measures were prescribed in >70% of patients. There is definitely need for improvement of diagnosing CMA in primary care.

  18. General IDRC Funding Guidelines

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

    Loretta Rocca

    Budget Format. Allowable Expenses. Local Contributions. Letter of Official Request. Grant Agreement. Open Access. Applicant Organizations. In order for IDRC to enter into an agreement with an applicant organization, IDRC must be satisfied that the organization has independent legal status (or 'legal personality') and is ...

  19. Multivariate statistical modelling based on generalized linear models

    CERN Document Server

    Fahrmeir, Ludwig

    1994-01-01

    This book is concerned with the use of generalized linear models for univariate and multivariate regression analysis. Its emphasis is to provide a detailed introductory survey of the subject based on the analysis of real data drawn from a variety of subjects including the biological sciences, economics, and the social sciences. Where possible, technical details and proofs are deferred to an appendix in order to provide an accessible account for non-experts. Topics covered include: models for multi-categorical responses, model checking, time series and longitudinal data, random effects models, and state-space models. Throughout, the authors have taken great pains to discuss the underlying theoretical ideas in ways that relate well to the data at hand. As a result, numerous researchers whose work relies on the use of these models will find this an invaluable account to have on their desks. "The basic aim of the authors is to bring together and review a large part of recent advances in statistical modelling of m...

  20. Guidelines for Developing and Reporting Machine Learning Predictive Models in Biomedical Research: A Multidisciplinary View.

    Science.gov (United States)

    Luo, Wei; Phung, Dinh; Tran, Truyen; Gupta, Sunil; Rana, Santu; Karmakar, Chandan; Shilton, Alistair; Yearwood, John; Dimitrova, Nevenka; Ho, Tu Bao; Venkatesh, Svetha; Berk, Michael

    2016-12-16

    As more and more researchers are turning to big data for new opportunities of biomedical discoveries, machine learning models, as the backbone of big data analysis, are mentioned more often in biomedical journals. However, owing to the inherent complexity of machine learning methods, they are prone to misuse. Because of the flexibility in specifying machine learning models, the results are often insufficiently reported in research articles, hindering reliable assessment of model validity and consistent interpretation of model outputs. To attain a set of guidelines on the use of machine learning predictive models within clinical settings to make sure the models are correctly applied and sufficiently reported so that true discoveries can be distinguished from random coincidence. A multidisciplinary panel of machine learning experts, clinicians, and traditional statisticians were interviewed, using an iterative process in accordance with the Delphi method. The process produced a set of guidelines that consists of (1) a list of reporting items to be included in a research article and (2) a set of practical sequential steps for developing predictive models. A set of guidelines was generated to enable correct application of machine learning models and consistent reporting of model specifications and results in biomedical research. We believe that such guidelines will accelerate the adoption of big data analysis, particularly with machine learning methods, in the biomedical research community. ©Wei Luo, Dinh Phung, Truyen Tran, Sunil Gupta, Santu Rana, Chandan Karmakar, Alistair Shilton, John Yearwood, Nevenka Dimitrova, Tu Bao Ho, Svetha Venkatesh, Michael Berk. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 16.12.2016.

  1. Recreational drug use among individuals living with HIV in Europe: review of the prevalence, comparison with the general population and HIV guidelines recommendations

    Directory of Open Access Journals (Sweden)

    Noe eGarin

    2015-07-01

    Full Text Available BACKGROUNDAdherence problems, interactions and higher rate of risk activities have been observed in HIV individuals using recreational drugs. Our aim was to describe recreational drug use in both HIV individuals and general population in Europe, and to assess at what extent HIV guidelines address this issue.METHODSData on recreational drug use across Europe were obtained from the European Monitoring Centre for Drugs and Drug Addiction for the general population, and through Pubmed search. for HIV patients. We assessed the incorporation of recreational drug issues in HIV treatment guidelines for the following topics: a recreational drugs; b adherence to antiretrovirals; c interactions; d transmission risk. Guidelines included: World Health Organization; European Aids Clinical Society; U.S. Department of Health and Human Services; International Antiviral Society-USA; and seven European national guidelines.RESULTS29 countries reported recreational drug use in general population. The highest prevalences were observed for Cannabis (i.e. 8-10% in Spain, France and Czech Republic followed by cocaine, amphetamines and ecstasy. The 13 studies selected in the systematic review showed a great variability in recreational drug use on the HIV population. Apart from classical recreational drugs, we found a relevant use of new drugs including sexual experience enhancers. Polydrug consumption was about 50% in some studies. Most guidelines included general information about recreational drugs, showing great variability on the inclusion of the evaluated topics. We found more specific, evidence-based recommendations on interactions, followed by medication adherence and transmission risk.CONCLUSIONSAvailable data on the people living with HIV suggest a higher use of recreational drugs than in the general population, which is already relevant. However, recreational drug issues should be included or addressed more thoroughly in most guidelines.

  2. The ECHAM3 atmospheric general circulation model

    International Nuclear Information System (INIS)

    1993-09-01

    The ECHAM model has been developed from the ECMWF model (cycle 31, November 1988). It contains several changes, mostly in the parameterization, in order to adjust the model for climate simulations. The technical details of the ECHAM operational model are described. (orig./KW)

  3. Ten-year follow-up on adoption of endodontic technology and clinical guidelines amongst Danish general dental practitioners.

    Science.gov (United States)

    Markvart, Merete; Fransson, Helena; Bjørndal, Lars

    2018-03-09

    The aim of this study was to re-assess the adoption of certain endodontic technology and central treatment principles of root canal treatments as advocated by guidelines presented by the European Society of Endodontology. The questionnaire included the same questions in 2003 and 2013. The general dental practitioners (GDPs) anonymously reported how frequent ('often', 'occasionally', and 'never') they used certain endodontic technology and adhered to central treatment principles. The statistical analyses were performed using Chi-squared test and Goodman-Kruskal's γ-coefficient as an association measure. The overall response rate of the 2013 group was 46.5% (n = 531). The frequencies of GDPs reporting often use of rubber dam, apex locator and rotary NiTi instruments were significantly higher (p Adoption was significantly influenced by the factors gender (p = .601) and time since graduation (p = .361), and the cluster analyses revealed the neglected use of rubber dam to be associated with no established postoperative recall system. After 10 years, there was a higher frequency of GDPs who had adopted certain endodontic technologies. However, progress towards high-quality root canal treatment might be obstructed as the majority of GDPs avoids consistent use of rubber dam, and routinely neglects recalls for postoperative controls of their endodontic treatments.

  4. General problems of modeling for accelerators

    International Nuclear Information System (INIS)

    Luccio, A.

    1991-01-01

    In this presentation the author only discusses problems of modeling for circular accelerators and bases the examples on the AGS Booster Synchrotron presently being commissioned at BNL. A model is a platonic representation of an accelerator. With algorithms, implemented through computer codes, the model is brought to life. At the start of a new accelerator project, the model and the real machine are taking shape somewhat apart. They get closer and closer as the project goes on. Ideally, the modeler is only satisfied when the model or the machine cannot be distinguished. Accelerator modeling for real time control has specific problems. If one wants fast responses, algorithms may be implemented in hardware or by parallel computation, perhaps by neural networks. Algorithms and modeling is not only for accelerator control. It is also for: accelerator parameter measurement; hardware problem debugging, perhaps with some help of artificial intelligence; operator training, much like a flight simulator

  5. generalized constitutive model for stabilized quick clay

    African Journals Online (AJOL)

    QUICK CLAY. PANCRAS MUGISHAGWE BUJULU AND GUSTAV GRIMSTAD. ABSTRACT. An experimentally-based two yield surface constitutive model for cemented quick clay has been ... Clay Model, the Koiter Rule and two Mapping Rules. .... models, where a mobilization formulation is used, this is independent of q.

  6. Towards a General Model of Temporal Discounting

    Science.gov (United States)

    van den Bos, Wouter; McClure, Samuel M.

    2013-01-01

    Psychological models of temporal discounting have now successfully displaced classical economic theory due to the simple fact that many common behavior patterns, such as impulsivity, were unexplainable with classic models. However, the now dominant hyperbolic model of discounting is itself becoming increasingly strained. Numerous factors have…

  7. Development of a generalized integral jet model

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan; Kessler, A.; Markert, Frank

    2017-01-01

    model is needed to describe the rapid combustion of the flammable part of the plume (flash fire) and a third model has to be applied for the remaining jet fire. The objective of this paper is to describe the first steps of the development of an integral-type model describing the transient development...

  8. Involving migrants in the development of guidelines for communication in cross-cultural general practice consultations: a participatory learning and action research project

    NARCIS (Netherlands)

    O'Reilly-de Brún, M.P.; Macfarlane, A.; Brun, T. de; Okonkwo, E.; Bonsenge Bokanga, J.S.; Almeida Silva, M. de; Ogbebor, F.; Mierzejewska, A.; Nnadi, L.; Muijsenbergh, M.E.T.C. van den; Weel-Baumgarten, E.M. van; Weel, C. van

    2015-01-01

    OBJECTIVE: The aim of this research was to involve migrants and other key stakeholders in a participatory dialogue to develop a guideline for enhancing communication in cross-cultural general practice consultations. In this paper, we focus on findings about the use of formal versus informal

  9. Administered Activities in Pediatric Nuclear Medicine and the Impact of the 2010 North American Consensus Guidelines on General Hospitals in the United States.

    Science.gov (United States)

    Fahey, Frederic H; Ziniel, Sonja I; Manion, Dacie; Baker, Amanda; Treves, S Ted

    2016-09-01

    We sought to describe the practice of pediatric nuclear medicine at general hospitals in the United States and to assess the impact of dose awareness campaigns such as Image Gently. A web-based survey was developed that requested information regarding hospital type, whether the hospital practices pediatric nuclear medicine, and the hospital's method for determining the administered activity for children. The survey invitation was emailed to a sample of general hospitals with more than 300 beds, excluding dedicated pediatric, veterans, psychiatric, and rehabilitation hospitals. Data were collected for 5 procedures performed on children: (99m)Tc-methylene diphosphate (MDP) bone scans, (99m)Tc-mercaptoacetyltriglycine (MAG3) renograms, (99m)Tc-dimercaptosuccinic acid (DMSA) renal cortical scans, (99m)Tc-based hepatobiliary scans, and (18)F-FDG PET scans. The sites reported dosage by weight (MBq/kg), minimum and maximum dosages, and the activities that they would administer to 2 hypothetical patients: a 5-y-old boy (20 kg, 110 cm tall) and a 10-y-old girl (30 kg, 140 cm tall). The invitation was delivered to 196 sites, with 121 (61.7%) responding. Eighty-two hospitals (67.8%) performed nuclear medicine on children. All sites scaled administered activity for children, mostly by body weight. Also, 82.4% of sites indicated they were familiar with Image Gently, 57.1% were familiar with the 2010 North American consensus guidelines for children, and 54.9% altered their protocols because of the guidelines. The median value for parameters defined by the guidelines was equal to the guideline-recommended value for all procedures. More than 50% of the sites-particularly those familiar with the guidelines-were compliant with the guidelines regarding both the acquisition parameters and the administered activities for the 2 hypothetical patients. However, there remained a wide variation in practice, sometimes by more than a factor of 10, for sites not familiar with the guidelines

  10. generalized constitutive model for stabilized quick clay

    African Journals Online (AJOL)

    An experimentally-based two yield surface constitutive model for cemented quick clay has been developed at NTNU, Norway, to reproduce the mechanical behavior of the stabilized quick clay in the triaxial p'-q stress space. The model takes into account the actual mechanical properties of the stabilized material, such as ...

  11. Stratospheric General Circulation with Chemistry Model (SGCCM)

    Science.gov (United States)

    Rood, Richard B.; Douglass, Anne R.; Geller, Marvin A.; Kaye, Jack A.; Nielsen, J. Eric; Rosenfield, Joan E.; Stolarski, Richard S.

    1990-01-01

    In the past two years constituent transport and chemistry experiments have been performed using both simple single constituent models and more complex reservoir species models. Winds for these experiments have been taken from the data assimilation effort, Stratospheric Data Analysis System (STRATAN).

  12. Equilibrium in Generalized Cournot and Stackelberg Models

    NARCIS (Netherlands)

    Bulavsky, V.A.; Kalashnikov, V.V.

    1999-01-01

    A model of an oligopolistic market with a homogeneous product is examined. Each subject of the model uses a conjecture about the market response to variations of its production volume. The conjecture value depends upon both the current total volume of production at the market and the subject's

  13. Generalized coupling in the Kuramoto model

    DEFF Research Database (Denmark)

    Filatrella, G.; Pedersen, Niels Falsig; Wiesenfeld, K.

    2007-01-01

    We propose a modification of the Kuramoto model to account for the effective change in the coupling constant among the oscillators, as suggested by some experiments on Josephson junction, laser arrays, and mechanical systems, where the active elements are turned on one by one. The resulting model...... with the behavior of Josephson junctions coupled via a cavity....

  14. Multiloop functional renormalization group for general models

    Science.gov (United States)

    Kugler, Fabian B.; von Delft, Jan

    2018-02-01

    We present multiloop flow equations in the functional renormalization group (fRG) framework for the four-point vertex and self-energy, formulated for a general fermionic many-body problem. This generalizes the previously introduced vertex flow [F. B. Kugler and J. von Delft, Phys. Rev. Lett. 120, 057403 (2018), 10.1103/PhysRevLett.120.057403] and provides the necessary corrections to the self-energy flow in order to complete the derivative of all diagrams involved in the truncated fRG flow. Due to its iterative one-loop structure, the multiloop flow is well suited for numerical algorithms, enabling improvement of many fRG computations. We demonstrate its equivalence to a solution of the (first-order) parquet equations in conjunction with the Schwinger-Dyson equation for the self-energy.

  15. A guideline-based computerised decision support system (CDSS to influence general practitioners management of chronic heart failure

    Directory of Open Access Journals (Sweden)

    Eva Toth-Pal

    2008-05-01

    Conclusion Using a guideline-based CDSS for the GPs' own patient cases had an impact on the GPs' confidence in the diagnosis of chronic heart failure and their considerations about investigations and medications: they also perceived substantial support in every third case. Applying a CDSS developed using evidence-based guidelines for chronic heart failure in primary care could have a significant influence on GPs' disease management.

  16. Trends in patterns of antidepressant use in older general population between 2006 and 2012 following publication of practice guidelines.

    Science.gov (United States)

    Etchepare, Fanny; Pambrun, Elodie; Verdoux, Hélène; Tournier, Marie

    2017-08-01

    The French regulatory agency published in 2006 practice guidelines related to the management of depressive and anxiety disorders. The main objective of the study was to assess their impact regarding use and monitoring of antidepressant drug treatment in older patients. The secondary objective was to identify factors associated with compliance with practice guidelines. A historical fixed cohort study with dynamic follow-up time was conducted in 16,144 subjects aged 65 years and over, initiating antidepressant treatment and registered in the National Health Insurance Database between 2006 and 2012. Compliance with guidelines was assessed from year to year using segmented regression analysis. Multiple logistic regressions were used to identify factors associated with compliance with guidelines. Duration of antidepressant treatment was compliant with guidelines in 13.0% of patients aged 65-74 years and 18.5% of patients aged 75 years and over. Biological monitoring was performed in 12.6% of patients aged 65-74 years and 18.5% of patients aged 75 years and over. No significant change of rate of compliance with guidelines was observed over the study period. Compliance of prescriptions with guidelines was associated with patient's age, specialty of the prescriber, presence of chronic disease, year of treatment initiation, and presence of a university hospital in the area of residence. While treatment duration and biological monitoring were often inadequate in older patients, the publication of guidelines by the French health regulatory authorities did not lead to any significant and sustained improvement in their patterns of antidepressant use. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Generalized Path Analysis and Generalized Simultaneous Equations Model for Recursive Systems with Responses of Mixed Types

    Science.gov (United States)

    Tsai, Tien-Lung; Shau, Wen-Yi; Hu, Fu-Chang

    2006-01-01

    This article generalizes linear path analysis (PA) and simultaneous equations models (SiEM) to deal with mixed responses of different types in a recursive or triangular system. An efficient instrumental variable (IV) method for estimating the structural coefficients of a 2-equation partially recursive generalized path analysis (GPA) model and…

  18. Description of the General Equilibrium Model of Ecosystem Services (GEMES)

    Science.gov (United States)

    Travis Warziniack; David Finnoff; Jenny Apriesnig

    2017-01-01

    This paper serves as documentation for the General Equilibrium Model of Ecosystem Services (GEMES). GEMES is a regional computable general equilibrium model that is composed of values derived from natural capital and ecosystem services. It models households, producing sectors, and governments, linked to one another through commodity and factor markets. GEMES was...

  19. Summary guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Halsnaes, K.; Painuly, J.P.; Turkson, J.; Meyer, H.J.; Markandya, A.

    1999-09-01

    This document is a summary version of the methodological guidelines for climate change mitigation assessment developed as part of the Global Environment Facility (GEF) project Economics of Greenhouse Gas Limitations; Methodological Guidelines. The objectives of this project have been to develop a methodology, an implementing framework and a reporting system which countries can use in the construction of national climate change mitigation policies and in meeting their future reporting obligations under the FCCC. The methodological framework developed in the Methodological Guidelines covers key economic concepts, scenario building, modelling tools and common assumptions. It was used by several country studies included in the project. (au) 13 refs.

  20. Application of a conceptual framework for the modelling and execution of clinical guidelines as networks of concurrent processes

    NARCIS (Netherlands)

    Fung, L.S.N.; Fung, Nick Lik San; Widya, I.A.; Broens, T.H.F.; Larburu Rubio, Nekane; Bults, Richard G.A.; Shalom, Erez; Jones, Valerie M.; Hermens, Hermanus J.

    2014-01-01

    We present a conceptual framework for modelling clinical guidelines as networks of concurrent processes. This enables the guideline to be partitioned and distributed at run-time across a knowledge-based telemedicine system, which is distributed by definition but whose exact physical configuration

  1. The Five-Factor Model: General Overview

    Directory of Open Access Journals (Sweden)

    A A Vorobyeva

    2011-12-01

    Full Text Available The article describes the five-factor model (FFM, giving an overview of its history, basic dimensions, cross-cultural research conducted on the model and highlights some practical studies based on the FFM, including the studies on job performance, leader performance and daily social interactions. An overview of the recent five-factor theory is also provided. According to the theory, the five factors are encoded in human genes, therefore it is almost impossible to change the basic factors themselves, but a person's behavior might be changed due to characteristic adaptations which do not alter personality dimensions, only a person's behavior.

  2. Esperanto: A Unique Model for General Linguistics.

    Science.gov (United States)

    Dulichenko, Aleksandr D.

    1988-01-01

    Esperanto presents a unique model for linguistic research by allowing the study of language development from project to fully functioning language. Esperanto provides insight into the growth of polysemy and redundancy, as well as into language universals and the phenomenon of social control. (Author/CB)

  3. Ethical guidelines, animal profile, various animal models used in periodontal research with alternatives and future perspectives

    Directory of Open Access Journals (Sweden)

    Mohan Kumar Pasupuleti

    2016-01-01

    Full Text Available Laboratory animal models serve as a facilitator to investigate the etiopathogenesis of periodontal disease, are used to know the efficacy of reconstructive and regenerative procedures, and are also helpful in evaluation of newer therapeutic techniques including laser and implant therapies prior to application in the human beings. The aim of this review is to know the different animal models used in various specialties of dental research and to know the ethical guidelines prior to the usage of experimental models with main emphasis on how to refine, replace, and reduce the number of animal models usage in the laboratory. An online search for experimental animal models used in dental research was performed using MEDLINE/PubMed database. Publications from 2009 to May 2013 in the specialty of periodontics were included in writing this review. A total of 652 references were published in PubMed/MEDLINE databases based on the search terms used. Out of 245 studies, 241 were related to the periodontal research published in English from 2009 to 2013. Relevant papers were chosen according to the inclusion and exclusion criteria. After extensive electronic and hand search on animal models, it has been observed that various animal models were used in dental research. Search on animal models used for dental research purpose revealed that various animals such as rats, mice, guinea pigs, rabbit, beagle dogs, goats, and nonhuman primates were extensively used. However, with the new advancement of ex vivo animal models, it has become easy to investigate disease pathogenesis and to test the efficacy of newer therapeutic modalities with the reduced usage of animal models. This review summarized the large amount of literature on animal models used in periodontal research with main emphasis on ethical guidelines and on reducing the animal model usage in future perspective.

  4. Practical likelihood analysis for spatial generalized linear mixed models

    DEFF Research Database (Denmark)

    Bonat, W. H.; Ribeiro, Paulo Justiniano

    2016-01-01

    , respectively, examples of binomial and count datasets modeled by spatial generalized linear mixed models. Our results show that the Laplace approximation provides similar estimates to Markov Chain Monte Carlo likelihood, Monte Carlo expectation maximization, and modified Laplace approximation. Some advantages...

  5. Development of independent generalized probabilistic models for regulatory activities

    International Nuclear Information System (INIS)

    Gashev, M.Kh.; Zinchenko, Yu.A.; Stefanishin, N.A.

    2012-01-01

    The paper discusses the development of probabilistic models to be used in regulatory activities. Results from the development of independent generalized PSA-1 models for purposes of SNRIU risk-informed regulation are presented

  6. Modeling electrokinetics in ionic liquids: General

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chao [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA USA; Bao, Jie [Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland WA USA; Pan, Wenxiao [Department of Mechanical Engineering, University of Wisconsin-Madison, Madison WI USA; Sun, Xin [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA USA

    2017-04-07

    Using direct numerical simulations we provide a thorough study on the electrokinetics of ionic liquids. In particular, the modfied Poisson-Nernst-Planck (MPNP) equations are solved to capture the crowding and overscreening effects that are the characteristics of an ionic liquid. For modeling electrokinetic flows in an ionic liquid, the MPNP equations are coupled with the Navier-Stokes equations to study the coupling of ion transport, hydrodynamics, and electrostatic forces. Specifically, we consider the ion transport between two parallel plates, charging dynamics in a 2D straight-walled pore, electro-osmotic ow in a nano-channel, electroconvective instability on a plane ion-selective surface, and electroconvective ow on a curved ion-selective surface. We discuss how the crowding and overscreening effects and their interplay affect the electrokinetic behaviors of ionic liquids in these application problems.

  7. Anisotropic cosmological models and generalized scalar tensor theory

    Indian Academy of Sciences (India)

    physics pp. 669–673. Anisotropic cosmological models and generalized scalar tensor theory. SUBENOY CHAKRABORTY1,*, BATUL CHANDRA SANTRA2 and ... Anisotropic cosmological models; general scalar tensor theory; inflation. PACS Nos 98.80.Hw; 04.50.+h; 98.80.Cq. 1. Introduction. Brans–Dicke theory [1] (BD ...

  8. Model-free adaptive sliding mode controller design for generalized ...

    Indian Academy of Sciences (India)

    L M WANG

    2017-08-16

    Aug 16, 2017 ... A novel model-free adaptive sliding mode strategy is proposed for a generalized projective synchronization (GPS) ... the neural network theory, a model-free adaptive sliding mode controller is designed to guarantee asymptotic stability of the generalized ..... following optimization parameters are needed: ⎧.

  9. Managing heteroscedasticity in general linear models.

    Science.gov (United States)

    Rosopa, Patrick J; Schaffer, Meline M; Schroeder, Amber N

    2013-09-01

    Heteroscedasticity refers to a phenomenon where data violate a statistical assumption. This assumption is known as homoscedasticity. When the homoscedasticity assumption is violated, this can lead to increased Type I error rates or decreased statistical power. Because this can adversely affect substantive conclusions, the failure to detect and manage heteroscedasticity could have serious implications for theory, research, and practice. In addition, heteroscedasticity is not uncommon in the behavioral and social sciences. Thus, in the current article, we synthesize extant literature in applied psychology, econometrics, quantitative psychology, and statistics, and we offer recommendations for researchers and practitioners regarding available procedures for detecting heteroscedasticity and mitigating its effects. In addition to discussing the strengths and weaknesses of various procedures and comparing them in terms of existing simulation results, we describe a 3-step data-analytic process for detecting and managing heteroscedasticity: (a) fitting a model based on theory and saving residuals, (b) the analysis of residuals, and (c) statistical inferences (e.g., hypothesis tests and confidence intervals) involving parameter estimates. We also demonstrate this data-analytic process using an illustrative example. Overall, detecting violations of the homoscedasticity assumption and mitigating its biasing effects can strengthen the validity of inferences from behavioral and social science data.

  10. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Executive summary

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written to provide guidance to managers and site operators on how ground-water transport codes should be selected for assessing burial site performance. There is a need for a formal approach to selecting appropriate codes from the multitude of potentially useful ground-water transport codes that are currently available. Code selection is a problem that requires more than merely considering mathematical equation-solving methods. These guidelines are very general and flexible and are also meant for developing systems simulation models to be used to assess the environmental safety of low-level waste burial facilities. Code selection is only a single aspect of the overall objective of developing a systems simulation model for a burial site. The guidance given here is mainly directed toward applications-oriented users, but managers and site operators need to be familiar with this information to direct the development of scientifically credible and defensible transport assessment models. Some specific advice for managers and site operators on how to direct a modeling exercise is based on the following five steps: identify specific questions and study objectives; establish costs and schedules for achieving answers; enlist the aid of professional model applications group; decide on approach with applications group and guide code selection; and facilitate the availability of site-specific data. These five steps for managers/site operators are discussed in detail following an explanation of the nine systems model development steps, which are presented first to clarify what code selection entails

  11. A generalized model via random walks for information filtering

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhuo-Ming, E-mail: zhuomingren@gmail.com [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland); Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, ChongQing, 400714 (China); Kong, Yixiu [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland); Shang, Ming-Sheng, E-mail: msshang@cigit.ac.cn [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, ChongQing, 400714 (China); Zhang, Yi-Cheng [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland)

    2016-08-06

    There could exist a simple general mechanism lurking beneath collaborative filtering and interdisciplinary physics approaches which have been successfully applied to online E-commerce platforms. Motivated by this idea, we propose a generalized model employing the dynamics of the random walk in the bipartite networks. Taking into account the degree information, the proposed generalized model could deduce the collaborative filtering, interdisciplinary physics approaches and even the enormous expansion of them. Furthermore, we analyze the generalized model with single and hybrid of degree information on the process of random walk in bipartite networks, and propose a possible strategy by using the hybrid degree information for different popular objects to toward promising precision of the recommendation. - Highlights: • We propose a generalized recommendation model employing the random walk dynamics. • The proposed model with single and hybrid of degree information is analyzed. • A strategy with the hybrid degree information improves precision of recommendation.

  12. A generalized model via random walks for information filtering

    International Nuclear Information System (INIS)

    Ren, Zhuo-Ming; Kong, Yixiu; Shang, Ming-Sheng; Zhang, Yi-Cheng

    2016-01-01

    There could exist a simple general mechanism lurking beneath collaborative filtering and interdisciplinary physics approaches which have been successfully applied to online E-commerce platforms. Motivated by this idea, we propose a generalized model employing the dynamics of the random walk in the bipartite networks. Taking into account the degree information, the proposed generalized model could deduce the collaborative filtering, interdisciplinary physics approaches and even the enormous expansion of them. Furthermore, we analyze the generalized model with single and hybrid of degree information on the process of random walk in bipartite networks, and propose a possible strategy by using the hybrid degree information for different popular objects to toward promising precision of the recommendation. - Highlights: • We propose a generalized recommendation model employing the random walk dynamics. • The proposed model with single and hybrid of degree information is analyzed. • A strategy with the hybrid degree information improves precision of recommendation.

  13. Practical guidelines for modelling post-entry spread in invasion ecology

    Directory of Open Access Journals (Sweden)

    Hazel Parry

    2013-09-01

    Full Text Available In this article we review a variety of methods to enable understanding and modelling the spread of a pest or pathogen post-entry. Building upon our experience of multidisciplinary research in this area, we propose practical guidelines and a framework for model development, to help with the application of mathematical modelling in the field of invasion ecology for post-entry spread. We evaluate the pros and cons of a range of methods, including references to examples of the methods in practice. We also show how issues of data deficiency and uncertainty can be addressed. The aim is to provide guidance to the reader on the most suitable elements to include in a model of post-entry dispersal in a risk assessment, under differing circumstances. We identify both the strengths and weaknesses of different methods and their application as part of a holistic, multidisciplinary approach to biosecurity research.

  14. General Friction Model Extended by the Effect of Strain Hardening

    DEFF Research Database (Denmark)

    Nielsen, Chris V.; Martins, Paulo A.F.; Bay, Niels

    2016-01-01

    An extension to the general friction model proposed by Wanheim and Bay [1] to include the effect of strain hardening is proposed. The friction model relates the friction stress to the fraction of real contact area by a friction factor under steady state sliding. The original model for the real...... contact area as function of the normalized contact pressure is based on slip-line analysis and hence on the assumption of rigid-ideally plastic material behavior. In the present work, a general finite element model is established to, firstly, reproduce the original model under the assumption of rigid......-ideally plastic material, and secondly, to extend the solution by the influence of material strain hardening. This corresponds to adding a new variable and, therefore, a new axis to the general friction model. The resulting model is presented in a combined function suitable for e.g. finite element modeling...

  15. A holistic antenatal model based on yoga, Ayurveda, and Vedic guidelines.

    Science.gov (United States)

    Rakhshani, Abbas; Nagarathna, Raghuram; Sharma, Ahalya; Singh, Amit; Nagendra, Hongasandra Ramarao

    2015-01-01

    The prevalence of pregnancy complications are on the rise globally with severe consequences. According to the World Health Organization (WHO, 2009), every minute, at least one woman dies and 20 are affected by the complications related to pregnancy or childbirth. While the root cause of pregnancy complications is unclear, it likely has physical, psychological, social, and spiritual aspects. The Vedas are a rich source of antenatal health care guidelines in all these aspects. The primary objective of the authors was to compile the scriptural and scientific evidence for a holistic antenatal model of yoga with emphasis on sociocultural Indian practices.

  16. Reliability assessment of competing risks with generalized mixed shock models

    International Nuclear Information System (INIS)

    Rafiee, Koosha; Feng, Qianmei; Coit, David W.

    2017-01-01

    This paper investigates reliability modeling for systems subject to dependent competing risks considering the impact from a new generalized mixed shock model. Two dependent competing risks are soft failure due to a degradation process, and hard failure due to random shocks. The shock process contains fatal shocks that can cause hard failure instantaneously, and nonfatal shocks that impact the system in three different ways: 1) damaging the unit by immediately increasing the degradation level, 2) speeding up the deterioration by accelerating the degradation rate, and 3) weakening the unit strength by reducing the hard failure threshold. While the first impact from nonfatal shocks comes from each individual shock, the other two impacts are realized when the condition for a new generalized mixed shock model is satisfied. Unlike most existing mixed shock models that consider a combination of two shock patterns, our new generalized mixed shock model includes three classic shock patterns. According to the proposed generalized mixed shock model, the degradation rate and the hard failure threshold can simultaneously shift multiple times, whenever the condition for one of these three shock patterns is satisfied. An example using micro-electro-mechanical systems devices illustrates the effectiveness of the proposed approach with sensitivity analysis. - Highlights: • A rich reliability model for systems subject to dependent failures is proposed. • The degradation rate and the hard failure threshold can shift simultaneously. • The shift is triggered by a new generalized mixed shock model. • The shift can occur multiple times under the generalized mixed shock model.

  17. Model Reduction of Switched Systems Based on Switching Generalized Gramians

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza; Wisniewski, Rafal

    2012-01-01

    In this paper, a general method for model order reduction of discrete-time switched linear systems is presented. The proposed technique uses switching generalized gramians. It is shown that several classical reduction methods can be developed into the generalized gramian framework for the model...... reduction of linear systems and for the reduction of switched systems. Discrete-time balanced reduction within a specified frequency interval is taken as an example within this framework. To avoid numerical instability and to increase the numerical efficiency, a generalized gramian-based Petrov...

  18. A General Polygon-based Deformable Model for Object Recognition

    DEFF Research Database (Denmark)

    Jensen, Rune Fisker; Carstensen, Jens Michael

    1999-01-01

    We propose a general scheme for object localization and recognition based on a deformable model. The model combines shape and image properties by warping a arbitrary prototype intensity template according to the deformation in shape. The shape deformations are constrained by a probabilistic...... distribution, which combined with a match of the warped intensity template and the image form the final criteria used for localization and recognition of a given object. The chosen representation gives the model an ability to model an almost arbitrary object. Beside the actual model a full general scheme...

  19. Generalized Linear Models with Applications in Engineering and the Sciences

    CERN Document Server

    Myers, Raymond H; Vining, G Geoffrey; Robinson, Timothy J

    2012-01-01

    Praise for the First Edition "The obvious enthusiasm of Myers, Montgomery, and Vining and their reliance on their many examples as a major focus of their pedagogy make Generalized Linear Models a joy to read. Every statistician working in any area of applied science should buy it and experience the excitement of these new approaches to familiar activities."-Technometrics Generalized Linear Models: With Applications in Engineering and the Sciences, Second Edition continues to provide a clear introduction to the theoretical foundations and key applications of generalized linear models (GLMs). Ma

  20. Adherence of Surgeons to Antimicrobial Prophylaxis Guidelines in a Tertiary General Hospital in a Rapidly Developing Country

    Directory of Open Access Journals (Sweden)

    Ahmed Abdel-Aziz

    2013-01-01

    Full Text Available Objectives. To assess the standard practice of care of surgeons regarding surgical antibiotic prophylaxis, to identify gaps, and to set recommendations. Methods. A retrospective analysis of data obtained from different surgical units in a single center in Qatar over a 3-month period in 2012. A total of 101 patients who underwent surgery and followed regimes for surgical prophylaxis as per hospital guidelines were included in the study. Results. The overall use of antibiotic was 89%, whereas the current practice did not match the recommended hospital protocols in 53.5% of cases. Prolonged antibiotics use (59.3% was the commonest reason for nonadherence followed by the use of an alternative antibiotic to that recommended in the protocol (31.5% and no prophylaxis was used in 9.2% of cases. The rate of compliance was significantly higher among clean surgery than clean contaminated group (P=0.03. Forty-four percent of clean and 65% of clean-contaminated procedures showed noncompliance with the recommended surgical antimicrobial prophylaxis hospital guidelines. Conclusion. Lack of adherence to hospital protocols is not uncommon. This finding remains a challenge to encourage clinicians to follow hospital guidelines appropriately and to consistently apply the surgical antibiotic prophylaxis. The role of clinical pharmacist may facilitate this process across all surgical disciplines.

  1. Critical factors influencing physicians' intention to use computerized clinical practice guidelines: an integrative model of activity theory and the technology acceptance model.

    Science.gov (United States)

    Hsiao, Ju-Ling; Chen, Rai-Fu

    2016-01-16

    With the widespread use of information communication technologies, computerized clinical practice guidelines are developed and considered as effective decision supporting tools in assisting the processes of clinical activities. However, the development of computerized clinical practice guidelines in Taiwan is still at the early stage and acceptance level among major users (physicians) of computerized clinical practice guidelines is not satisfactory. This study aims to investigate critical factors influencing physicians' intention to computerized clinical practice guideline use through an integrative model of activity theory and the technology acceptance model. The survey methodology was employed to collect data from physicians of the investigated hospitals that have implemented computerized clinical practice guidelines. A total of 505 questionnaires were sent out, with 238 completed copies returned, indicating a valid response rate of 47.1 %. The collected data was then analyzed by structural equation modeling technique. The results showed that attitudes toward using computerized clinical practice guidelines (γ = 0.451, p practice guidelines (γ = 0.219, p practice guidelines, and these factors can explain 68.6 % of the variance in intention to use computerized clinical practice guidelines. This study confirmed that some subject (human) factors, environment (organization) factors, tool (technology) factors mentioned in the activity theory should be carefully considered when introducing computerized clinical practice guidelines. Managers should pay much attention on those identified factors and provide adequate resources and incentives to help the promotion and use of computerized clinical practice guidelines. Through the appropriate use of computerized clinical practice guidelines, the clinical benefits, particularly in improving quality of care and facilitating the clinical processes, will be realized.

  2. Linear and Generalized Linear Mixed Models and Their Applications

    CERN Document Server

    Jiang, Jiming

    2007-01-01

    This book covers two major classes of mixed effects models, linear mixed models and generalized linear mixed models, and it presents an up-to-date account of theory and methods in analysis of these models as well as their applications in various fields. The book offers a systematic approach to inference about non-Gaussian linear mixed models. Furthermore, it has included recently developed methods, such as mixed model diagnostics, mixed model selection, and jackknife method in the context of mixed models. The book is aimed at students, researchers and other practitioners who are interested

  3. Simulation modelling in agriculture: General considerations. | R.I. ...

    African Journals Online (AJOL)

    The computer does all the necessary arithmetic when the hypothesis is invoked to predict the future behaviour of the simulated system under given conditions.A general ... in the advisory service. Keywords: agriculture; botany; computer simulation; modelling; simulation model; simulation modelling; south africa; techniques ...

  4. A Duality Result for the Generalized Erlang Risk Model

    Directory of Open Access Journals (Sweden)

    Lanpeng Ji

    2014-11-01

    Full Text Available In this article, we consider the generalized Erlang risk model and its dual model. By using a conditional measure-preserving correspondence between the two models, we derive an identity for two interesting conditional probabilities. Applications to the discounted joint density of the surplus prior to ruin and the deficit at ruin are also discussed.

  5. Critical Comments on the General Model of Instructional Communication

    Science.gov (United States)

    Walton, Justin D.

    2014-01-01

    This essay presents a critical commentary on McCroskey et al.'s (2004) general model of instructional communication. In particular, five points are examined which make explicit and problematize the meta-theoretical assumptions of the model. Comments call attention to the limitations of the model and argue for a broader approach to…

  6. Hierarchical Generalized Linear Models for the Analysis of Judge Ratings

    Science.gov (United States)

    Muckle, Timothy J.; Karabatsos, George

    2009-01-01

    It is known that the Rasch model is a special two-level hierarchical generalized linear model (HGLM). This article demonstrates that the many-faceted Rasch model (MFRM) is also a special case of the two-level HGLM, with a random intercept representing examinee ability on a test, and fixed effects for the test items, judges, and possibly other…

  7. A PROPOSAL FOR GENERALIZATION OF 3D MODELS

    Directory of Open Access Journals (Sweden)

    A. Uyar

    2017-11-01

    Full Text Available In recent years, 3D models have been created of many cities around the world. Most of the 3D city models have been introduced as completely graphic or geometric models, and the semantic and topographic aspects of the models have been neglected. In order to use 3D city models beyond the task, a generalization is necessary. CityGML is an open data model and XML-based format for the storage and exchange of virtual 3D city models. Level of Details (LoD which is an important concept for 3D modelling, can be defined as outlined degree or prior representation of real-world objects. The paper aim is first describes some requirements of 3D model generalization, then presents problems and approaches that have been developed in recent years. In conclude the paper will be a summary and outlook on problems and future work.

  8. a Proposal for Generalization of 3d Models

    Science.gov (United States)

    Uyar, A.; Ulugtekin, N. N.

    2017-11-01

    In recent years, 3D models have been created of many cities around the world. Most of the 3D city models have been introduced as completely graphic or geometric models, and the semantic and topographic aspects of the models have been neglected. In order to use 3D city models beyond the task, a generalization is necessary. CityGML is an open data model and XML-based format for the storage and exchange of virtual 3D city models. Level of Details (LoD) which is an important concept for 3D modelling, can be defined as outlined degree or prior representation of real-world objects. The paper aim is first describes some requirements of 3D model generalization, then presents problems and approaches that have been developed in recent years. In conclude the paper will be a summary and outlook on problems and future work.

  9. The DINA model as a constrained general diagnostic model: Two variants of a model equivalency.

    Science.gov (United States)

    von Davier, Matthias

    2014-02-01

    The 'deterministic-input noisy-AND' (DINA) model is one of the more frequently applied diagnostic classification models for binary observed responses and binary latent variables. The purpose of this paper is to show that the model is equivalent to a special case of a more general compensatory family of diagnostic models. Two equivalencies are presented. Both project the original DINA skill space and design Q-matrix using mappings into a transformed skill space as well as a transformed Q-matrix space. Both variants of the equivalency produce a compensatory model that is mathematically equivalent to the (conjunctive) DINA model. This equivalency holds for all DINA models with any type of Q-matrix, not only for trivial (simple-structure) cases. The two versions of the equivalency presented in this paper are not implied by the recently suggested log-linear cognitive diagnosis model or the generalized DINA approach. The equivalencies presented here exist independent of these recently derived models since they solely require a linear - compensatory - general diagnostic model without any skill interaction terms. Whenever it can be shown that one model can be viewed as a special case of another more general one, conclusions derived from any particular model-based estimates are drawn into question. It is widely known that multidimensional models can often be specified in multiple ways while the model-based probabilities of observed variables stay the same. This paper goes beyond this type of equivalency by showing that a conjunctive diagnostic classification model can be expressed as a constrained special case of a general compensatory diagnostic modelling framework. © 2013 The British Psychological Society.

  10. Graphical tools for model selection in generalized linear models.

    Science.gov (United States)

    Murray, K; Heritier, S; Müller, S

    2013-11-10

    Model selection techniques have existed for many years; however, to date, simple, clear and effective methods of visualising the model building process are sparse. This article describes graphical methods that assist in the selection of models and comparison of many different selection criteria. Specifically, we describe for logistic regression, how to visualize measures of description loss and of model complexity to facilitate the model selection dilemma. We advocate the use of the bootstrap to assess the stability of selected models and to enhance our graphical tools. We demonstrate which variables are important using variable inclusion plots and show that these can be invaluable plots for the model building process. We show with two case studies how these proposed tools are useful to learn more about important variables in the data and how these tools can assist the understanding of the model building process. Copyright © 2013 John Wiley & Sons, Ltd.

  11. General classical solutions in the noncommutative CPN-1 model

    International Nuclear Information System (INIS)

    Foda, O.; Jack, I.; Jones, D.R.T.

    2002-01-01

    We give an explicit construction of general classical solutions for the noncommutative CP N-1 model in two dimensions, showing that they correspond to integer values for the action and topological charge. We also give explicit solutions for the Dirac equation in the background of these general solutions and show that the index theorem is satisfied

  12. Parameter Estimation for a Computable General Equilibrium Model

    DEFF Research Database (Denmark)

    Arndt, Channing; Robinson, Sherman; Tarp, Finn

    We introduce a maximum entropy approach to parameter estimation for computable general equilibrium (CGE) models. The approach applies information theory to estimating a system of nonlinear simultaneous equations. It has a number of advantages. First, it imposes all general equilibrium constraints...

  13. Parameter Estimation for a Computable General Equilibrium Model

    DEFF Research Database (Denmark)

    Arndt, Channing; Robinson, Sherman; Tarp, Finn

    2002-01-01

    We introduce a maximum entropy approach to parameter estimation for computable general equilibrium (CGE) models. The approach applies information theory to estimating a system of non-linear simultaneous equations. It has a number of advantages. First, it imposes all general equilibrium constraints...

  14. General Computational Model for Human Musculoskeletal System of Spine

    Directory of Open Access Journals (Sweden)

    Kyungsoo Kim

    2012-01-01

    Full Text Available A general computational model of the human lumbar spine and trunk muscles including optimization formulations was provided. For a given condition, the trunk muscle forces could be predicted considering the human physiology including the follower load concept. The feasibility of the solution could be indirectly validated by comparing the compressive force, the shear force, and the joint moment. The presented general computational model and optimization technology can be fundamental tools to understand the control principle of human trunk muscles.

  15. Specific and General Human Capital in an Endogenous Growth Model

    OpenAIRE

    Evangelia Vourvachaki; Vahagn Jerbashian; : Sergey Slobodyan

    2014-01-01

    In this article, we define specific (general) human capital in terms of the occupations whose use is spread in a limited (wide) set of industries. We analyze the growth impact of an economy's composition of specific and general human capital, in a model where education and research and development are costly and complementary activities. The model suggests that a declining share of specific human capital, as observed in the Czech Republic, can be associated with a lower rate of long-term grow...

  16. Pricing Participating Products under a Generalized Jump-Diffusion Model

    Directory of Open Access Journals (Sweden)

    Tak Kuen Siu

    2008-01-01

    Full Text Available We propose a model for valuing participating life insurance products under a generalized jump-diffusion model with a Markov-switching compensator. It also nests a number of important and popular models in finance, including the classes of jump-diffusion models and Markovian regime-switching models. The Esscher transform is employed to determine an equivalent martingale measure. Simulation experiments are conducted to illustrate the practical implementation of the model and to highlight some features that can be obtained from our model.

  17. Generalized continua as models for classical and advanced materials

    CERN Document Server

    Forest, Samuel

    2016-01-01

    This volume is devoted to an actual topic which is the focus world-wide of various research groups. It contains contributions describing the material behavior on different scales, new existence and uniqueness theorems, the formulation of constitutive equations for advanced materials. The main emphasis of the contributions is directed on the following items - Modelling and simulation of natural and artificial materials with significant microstructure, - Generalized continua as a result of multi-scale models, - Multi-field actions on materials resulting in generalized material models, - Theories including higher gradients, and - Comparison with discrete modelling approaches.

  18. Extending the generalized Chaplygin gas model by using geometrothermodynamics

    Science.gov (United States)

    Aviles, Alejandro; Bastarrachea-Almodovar, Aztlán; Campuzano, Lorena; Quevedo, Hernando

    2012-09-01

    We use the formalism of geometrothermodynamics to derive fundamental thermodynamic equations that are used to construct general relativistic cosmological models. In particular, we show that the simplest possible fundamental equation, which corresponds in geometrothermodynamics to a system with no internal thermodynamic interaction, describes the different fluids of the standard model of cosmology. In addition, a particular fundamental equation with internal thermodynamic interaction is shown to generate a new cosmological model that correctly describes the dark sector of the Universe and contains as a special case the generalized Chaplygin gas model.

  19. Qualitative and quantitative guidelines for the comparison of environmental model predictions

    International Nuclear Information System (INIS)

    Scott, M.

    1995-03-01

    The question of how to assess or compare predictions from a number of models is one of concern in the validation of models, in understanding the effects of different models and model parameterizations on model output, and ultimately in assessing model reliability. Comparison of model predictions with observed data is the basic tool of model validation while comparison of predictions amongst different models provides one measure of model credibility. The guidance provided here is intended to provide qualitative and quantitative approaches (including graphical and statistical techniques) to such comparisons for use within the BIOMOVS II project. It is hoped that others may find it useful. It contains little technical information on the actual methods but several references are provided for the interested reader. The guidelines are illustrated on data from the VAMP CB scenario. Unfortunately, these data do not permit all of the possible approaches to be demonstrated since predicted uncertainties were not provided. The questions considered are concerned with a) intercomparison of model predictions and b) comparison of model predictions with the observed data. A series of examples illustrating some of the different types of data structure and some possible analyses have been constructed. A bibliography of references on model validation is provided. It is important to note that the results of the various techniques discussed here, whether qualitative or quantitative, should not be considered in isolation. Overall model performance must also include an evaluation of model structure and formulation, i.e. conceptual model uncertainties, and results for performance measures must be interpreted in this context. Consider a number of models which are used to provide predictions of a number of quantities at a number of time points. In the case of the VAMP CB scenario, the results include predictions of total deposition of Cs-137 and time dependent concentrations in various

  20. General adherence to guideline recommendations on initial diagnosis of bladder cancer in the United States and influencing factors.

    Science.gov (United States)

    Karl, Alexander; Adejoro, Oluwakayode; Saigal, Christopher; Konety, Badrinath

    2014-08-01

    Because international guidelines recommend best practices regarding staging of incident bladder cancer, we determined the adherence to such recommendations in the United States, performing a large retrospective database analysis. Patients with the diagnosis of urothelial cancer were identified in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database between 1992 and 2007. Staging procedures were identified and analyzed. As reference for published recommendations, we used the American Urological Association (AUA), European Association of Urology (EAU), and National Comprehensive Cancer Network (NCCN) guidelines. Based on these sources, recommended initial staging of bladder cancer was analyzed. Of all 56,130 patients, 6148 (10.9%) had a cytologic examination, 29,677 (52.9%) had a standard urinalysis, 2882 (5.1%) underwent intravenous pyelography (IVP), 6950 (12.4%) underwent retrograde pyelography (RPG), and 8145 (14.5%) had computed tomography/magnetic resonance imaging (CT/MRI). There was a significant trend over the years to a higher use of cytologic analysis, standard urinalysis, and CT/MRI. We observed a significant trend toward a lower rate of IVP and a stable use of RPG. The limitation of our study is that claims data are designed for payment processing, not quality measurement. Despite published recommendations on the initial diagnosis of bladder cancer, our data show that less than half of the included patients received all the elements thought to be required for an initial diagnosis of bladder cancer as recommended by guidelines. Greater adherence to recommendations may ensure optimal treatment strategies. Appropriate treatment is critical to patient outcomes, because evidence-based therapeutic management can be practiced only if an accurate assessment of the disease takes place at the time of initial diagnosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. MIG version 0.0 model interface guidelines: Rules to accelerate installation of numerical models into any compliant parent code

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, R.M.; Wong, M.K.

    1996-08-01

    A set of model interface guidelines, called MIG, is presented as a means by which any compliant numerical material model can be rapidly installed into any parent code without having to modify the model subroutines. Here, {open_quotes}model{close_quotes} usually means a material model such as one that computes stress as a function of strain, though the term may be extended to any numerical operation. {open_quotes}Parent code{close_quotes} means a hydrocode, finite element code, etc. which uses the model and enforces, say, the fundamental laws of motion and thermodynamics. MIG requires the model developer (who creates the model package) to specify model needs in a standardized but flexible way. MIG includes a dictionary of technical terms that allows developers and parent code architects to share a common vocabulary when specifying field variables. For portability, database management is the responsibility of the parent code. Input/output occurs via structured calling arguments. As much model information as possible (such as the lists of required inputs, as well as lists of precharacterized material data and special needs) is supplied by the model developer in an ASCII text file. Every MIG-compliant model also has three required subroutines to check data, to request extra field variables, and to perform model physics. To date, the MIG scheme has proven flexible in beta installations of a simple yield model, plus a more complicated viscodamage yield model, three electromechanical models, and a complicated anisotropic microcrack constitutive model. The MIG yield model has been successfully installed using identical subroutines in three vectorized parent codes and one parallel C++ code, all predicting comparable results. By maintaining one model for many codes, MIG facilitates code-to-code comparisons and reduces duplication of effort, thereby reducing the cost of installing and sharing models in diverse new codes.

  2. A Semi-Tychonic Model in General relativity

    Science.gov (United States)

    Murphy, George L.

    1998-10-01

    In the sixteenth century Tycho Brahe proposed a geocentric model of the solar system kinematically equivalent to the heliocentric Copernican model. There has been disagreement even among prominent relativists over whether or not relativity validates use of a geocentric model. Tycho's desire for a non-rotating earth cannot be satisfied, but we demonstrate here dynamical equivalence between a Copernican and a "semi-Tychonic" model by using an appropriate accelerated reference frame in general relativity. (The idea of absolute space in Newtonian mechanics makes use of Einstein's theory desirable even in the Newtonian approximation.) Optical questions are easily dealt with. Our treatment provides a satisfactory answer for the important historical question concerning geocentric and heliocentric models, and is also of pedagogic value. In addition, it gives insights into the real generality of general relativity, the nature of the relativistic equations of motion, and the analogy between coordinate and gauge transformations.

  3. Generalized entropy formalism and a new holographic dark energy model

    Science.gov (United States)

    Sayahian Jahromi, A.; Moosavi, S. A.; Moradpour, H.; Morais Graça, J. P.; Lobo, I. P.; Salako, I. G.; Jawad, A.

    2018-05-01

    Recently, the Rényi and Tsallis generalized entropies have extensively been used in order to study various cosmological and gravitational setups. Here, using a special type of generalized entropy, a generalization of both the Rényi and Tsallis entropy, together with holographic principle, we build a new model for holographic dark energy. Thereinafter, considering a flat FRW universe, filled by a pressureless component and the new obtained dark energy model, the evolution of cosmos has been investigated showing satisfactory results and behavior. In our model, the Hubble horizon plays the role of IR cutoff, and there is no mutual interaction between the cosmos components. Our results indicate that the generalized entropy formalism may open a new window to become more familiar with the nature of spacetime and its properties.

  4. A generalized model via random walks for information filtering

    Science.gov (United States)

    Ren, Zhuo-Ming; Kong, Yixiu; Shang, Ming-Sheng; Zhang, Yi-Cheng

    2016-08-01

    There could exist a simple general mechanism lurking beneath collaborative filtering and interdisciplinary physics approaches which have been successfully applied to online E-commerce platforms. Motivated by this idea, we propose a generalized model employing the dynamics of the random walk in the bipartite networks. Taking into account the degree information, the proposed generalized model could deduce the collaborative filtering, interdisciplinary physics approaches and even the enormous expansion of them. Furthermore, we analyze the generalized model with single and hybrid of degree information on the process of random walk in bipartite networks, and propose a possible strategy by using the hybrid degree information for different popular objects to toward promising precision of the recommendation.

  5. General Separations Area (GSA) Groundwater Flow Model Update: Hydrostratigraphic Data

    Energy Technology Data Exchange (ETDEWEB)

    Bagwell, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Bennett, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Flach, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-02-21

    This document describes the assembly, selection, and interpretation of hydrostratigraphic data for input to an updated groundwater flow model for the General Separations Area (GSA; Figure 1) at the Department of Energy’s (DOE) Savannah River Site (SRS). This report is one of several discrete but interrelated tasks that support development of an updated groundwater model (Bagwell and Flach, 2016).

  6. A MIXTURE LIKELIHOOD APPROACH FOR GENERALIZED LINEAR-MODELS

    NARCIS (Netherlands)

    WEDEL, M; DESARBO, WS

    1995-01-01

    A mixture model approach is developed that simultaneously estimates the posterior membership probabilities of observations to a number of unobservable groups or latent classes, and the parameters of a generalized linear model which relates the observations, distributed according to some member of

  7. Response of an ocean general circulation model to wind and ...

    Indian Academy of Sciences (India)

    The stretched-coordinate ocean general circulation model has been designed to study the observed variability due to wind and thermodynamic forcings. The model domain extends from 60°N to 60°S and cyclically continuous in the longitudinal direction. The horizontal resolution is 5° × 5° and 9 discrete vertical levels.

  8. Bianchi type IX string cosmological model in general relativity

    Indian Academy of Sciences (India)

    Abstract. We have investigated Bianchi type IX string cosmological models in general relativity. To get a determinate solution, we have assumed a condition p = λ i.e. rest energy density for a cloud of strings is equal to the string tension density. The various physical and geometrical aspects of the models are also discussed.

  9. Stability analysis for a general age-dependent vaccination model

    International Nuclear Information System (INIS)

    El Doma, M.

    1995-05-01

    An SIR epidemic model of a general age-dependent vaccination model is investigated when the fertility, mortality and removal rates depends on age. We give threshold criteria of the existence of equilibriums and perform stability analysis. Furthermore a critical vaccination coverage that is sufficient to eradicate the disease is determined. (author). 12 refs

  10. Bianchi type IX string cosmological model in general relativity

    Indian Academy of Sciences (India)

    We have investigated Bianchi type IX string cosmological models in general relativity. To get a determinate solution, we have assumed a condition ρ= i.e. rest energy density for a cloud of strings is equal to the string tension density. The various physical and geometrical aspects of the models are also discussed.

  11. Double generalized linear compound poisson models to insurance claims data

    DEFF Research Database (Denmark)

    Andersen, Daniel Arnfeldt; Bonat, Wagner Hugo

    2017-01-01

    This paper describes the specification, estimation and comparison of double generalized linear compound Poisson models based on the likelihood paradigm. The models are motivated by insurance applications, where the distribution of the response variable is composed by a degenerate distribution...... in a finite sample framework. The simulation studies are also used to validate the fitting algorithms and check the computational implementation. Furthermore, we investigate the impact of an unsuitable choice for the response variable distribution on both mean and dispersion parameter estimates. We provide R...... implementation and illustrate the application of double generalized linear compound Poisson models using a data set about car insurances....

  12. Factors prompting PSA-testing of asymptomatic men in a country with no guidelines: a national survey of general practitioners.

    LENUS (Irish Health Repository)

    Drummond, Frances J

    2009-01-01

    BACKGROUND: Increased use of prostate specific antigen (PSA) has been associated with increased prostate cancer incidence. Ireland is estimated to have one of the highest prostate cancer incidences in Europe and has no national guidelines for prostate cancer screening. GPs have a pivotal role in influencing PSA testing, therefore, our aim was to describe GP testing practices and to identify factors influencing these. METHODS: A postal survey, including questions on clinical practice and experience, knowledge and demographics was distributed to all GPs (n = 3,683). The main outcomes were (i) PSA testing asymptomatic men and (ii) "inappropriate" PSA testing, defined as testing asymptomatic men aged < 50 or > 75 years. Factors associated with these outcomes were identified using logistic regression. RESULTS: 1,625 GPs responded (response rate corrected for eligibility = 53%). Most respondents (79%) would PSA test asymptomatic men. Of these, 34% and 51% would test asymptomatic men < 50 and > 75 years, respectively. In multivariate analyses, GPs were more likely to test asymptomatic men if they were >or= 50 years, in practice >or= 10 years, female or less knowledgeable about PSA efficacy. Male GPs who would have a PSA test themselves were > 8-times more likely to PSA test asymptomatic men than GPs who would not have a test. GPs who had an asymptomatic patient diagnosed with prostate cancer following PSA testing, were > 3-times more likely to test asymptomatic men. Practice-related factors positively associated with testing included: running \\'well man\\' clinics, performing occupational health checks and performing other tests routinely with PSA. Factors positively associated with \\'inappropriate\\' testing included; being male and willing to have a PSA test, having worked\\/trained in the UK and supporting annual PSA testing. 91% of respondents supported the development of national PSA testing guidelines. CONCLUSION: Our findings suggest that widespread PSA testing

  13. Physically-Derived Dynamical Cores in Atmospheric General Circulation Models

    Science.gov (United States)

    Rood, Richard B.; Lin, Shian-Kiann

    1999-01-01

    The algorithm chosen to represent the advection in atmospheric models is often used as the primary attribute to classify the model. Meteorological models are generally classified as spectral or grid point, with the term grid point implying discretization using finite differences. These traditional approaches have a number of shortcomings that render them non-physical. That is, they provide approximate solutions to the conservation equations that do not obey the fundamental laws of physics. The most commonly discussed shortcomings are overshoots and undershoots which manifest themselves most overtly in the constituent continuity equation. For this reason many climate models have special algorithms to model water vapor advection. This talk focuses on the development of an atmospheric general circulation model which uses a consistent physically-based advection algorithm in all aspects of the model formulation. The shallow-water model of Lin and Rood (QJRMS, 1997) is generalized to three dimensions and combined with the physics parameterizations of NCAR's Community Climate Model. The scientific motivation for the development is to increase the integrity of the underlying fluid dynamics so that the physics terms can be more effectively isolated, examined, and improved. The expected benefits of the new model are discussed and results from the initial integrations will be presented.

  14. A general model for membrane-based separation processes

    DEFF Research Database (Denmark)

    Soni, Vipasha; Abildskov, Jens; Jonsson, Gunnar Eigil

    2009-01-01

    behaviour will play an important role. In this paper, modelling of membrane-based processes for separation of gas and liquid mixtures are considered. Two general models, one for membrane-based liquid separation processes (with phase change) and another for membrane-based gas separation are presented....... The separation processes covered are: membrane-based gas separation processes, pervaporation and various types of membrane distillation processes. The specific model for each type of membrane-based process is generated from the two general models by applying the specific system descriptions and the corresponding......A separation process could be defined as a process that transforms a given mixture of chemicals into two or more compositionally distinct end-use products. One way to design these separation processes is to employ a model-based approach, where mathematical models that reliably predict the process...

  15. Flexible Approaches to Computing Mediated Effects in Generalized Linear Models: Generalized Estimating Equations and Bootstrapping

    Science.gov (United States)

    Schluchter, Mark D.

    2008-01-01

    In behavioral research, interest is often in examining the degree to which the effect of an independent variable X on an outcome Y is mediated by an intermediary or mediator variable M. This article illustrates how generalized estimating equations (GEE) modeling can be used to estimate the indirect or mediated effect, defined as the amount by…

  16. QCD Sum Rules and Models for Generalized Parton Distributions

    Energy Technology Data Exchange (ETDEWEB)

    Anatoly Radyushkin

    2004-10-01

    I use QCD sum rule ideas to construct models for generalized parton distributions. To this end, the perturbative parts of QCD sum rules for the pion and nucleon electromagnetic form factors are interpreted in terms of GPDs and two models are discussed. One of them takes the double Borel transform at adjusted value of the Borel parameter as a model for nonforward parton densities, and another is based on the local duality relation. Possible ways of improving these Ansaetze are briefly discussed.

  17. Estimating and Forecasting Generalized Fractional Long Memory Stochastic Volatility Models

    Directory of Open Access Journals (Sweden)

    Shelton Peiris

    2017-12-01

    Full Text Available This paper considers a flexible class of time series models generated by Gegenbauer polynomials incorporating the long memory in stochastic volatility (SV components in order to develop the General Long Memory SV (GLMSV model. We examine the corresponding statistical properties of this model, discuss the spectral likelihood estimation and investigate the finite sample properties via Monte Carlo experiments. We provide empirical evidence by applying the GLMSV model to three exchange rate return series and conjecture that the results of out-of-sample forecasts adequately confirm the use of GLMSV model in certain financial applications.

  18. Generalized heat-transport equations: parabolic and hyperbolic models

    Science.gov (United States)

    Rogolino, Patrizia; Kovács, Robert; Ván, Peter; Cimmelli, Vito Antonio

    2018-03-01

    We derive two different generalized heat-transport equations: the most general one, of the first order in time and second order in space, encompasses some well-known heat equations and describes the hyperbolic regime in the absence of nonlocal effects. Another, less general, of the second order in time and fourth order in space, is able to describe hyperbolic heat conduction also in the presence of nonlocal effects. We investigate the thermodynamic compatibility of both models by applying some generalizations of the classical Liu and Coleman-Noll procedures. In both cases, constitutive equations for the entropy and for the entropy flux are obtained. For the second model, we consider a heat-transport equation which includes nonlocal terms and study the resulting set of balance laws, proving that the corresponding thermal perturbations propagate with finite speed.

  19. Australian and overseas models of general practice training.

    Science.gov (United States)

    Hays, Richard B; Morgan, Simon

    2011-06-06

    General practice training in Australia continues to evolve. It is now the responsibility of an independent organisation, is delivered by regional training providers, and comprises a structured training program. Overseas, general practice varies in its importance to health care systems, and training models differ considerably. In some cases training is mandatory, in others voluntary, but the aim is always similar--to improve the quality of care delivered to the large majority of populations that access health care through primary care. We review the current status of vocational general practice training in Australia, compare it with selected training programs in international contexts, and describe how the local model is well placed to address future challenges. Challenges include changes in population demographics, increasing comorbidity, increasing costs of technology-based health care, increasing globalisation of health, and workforce shortages. Although general practice training in Australia is strong, it can improve further by learning from other training programs to meet these challengers.

  20. Model-guided fieldwork: practical guidelines for multidisciplinary research on wildlife ecological and epidemiological dynamics.

    Science.gov (United States)

    Restif, Olivier; Hayman, David T S; Pulliam, Juliet R C; Plowright, Raina K; George, Dylan B; Luis, Angela D; Cunningham, Andrew A; Bowen, Richard A; Fooks, Anthony R; O'Shea, Thomas J; Wood, James L N; Webb, Colleen T

    2012-10-01

    Infectious disease ecology has recently raised its public profile beyond the scientific community due to the major threats that wildlife infections pose to biological conservation, animal welfare, human health and food security. As we start unravelling the full extent of emerging infectious diseases, there is an urgent need to facilitate multidisciplinary research in this area. Even though research in ecology has always had a strong theoretical component, cultural and technical hurdles often hamper direct collaboration between theoreticians and empiricists. Building upon our collective experience of multidisciplinary research and teaching in this area, we propose practical guidelines to help with effective integration among mathematical modelling, fieldwork and laboratory work. Modelling tools can be used at all steps of a field-based research programme, from the formulation of working hypotheses to field study design and data analysis. We illustrate our model-guided fieldwork framework with two case studies we have been conducting on wildlife infectious diseases: plague transmission in prairie dogs and lyssavirus dynamics in American and African bats. These demonstrate that mechanistic models, if properly integrated in research programmes, can provide a framework for holistic approaches to complex biological systems. © 2012 Crown copyright.

  1. GEMFsim: A Stochastic Simulator for the Generalized Epidemic Modeling Framework

    OpenAIRE

    Sahneh, Faryad Darabi; Vajdi, Aram; Shakeri, Heman; Fan, Futing; Scoglio, Caterina

    2016-01-01

    The recently proposed generalized epidemic modeling framework (GEMF) \\cite{sahneh2013generalized} lays the groundwork for systematically constructing a broad spectrum of stochastic spreading processes over complex networks. This article builds an algorithm for exact, continuous-time numerical simulation of GEMF-based processes. Moreover the implementation of this algorithm, GEMFsim, is available in popular scientific programming platforms such as MATLAB, R, Python, and C; GEMFsim facilitates ...

  2. Modeling the brain morphology distribution in the general aging population

    Science.gov (United States)

    Huizinga, W.; Poot, D. H. J.; Roshchupkin, G.; Bron, E. E.; Ikram, M. A.; Vernooij, M. W.; Rueckert, D.; Niessen, W. J.; Klein, S.

    2016-03-01

    Both normal aging and neurodegenerative diseases such as Alzheimer's disease cause morphological changes of the brain. To better distinguish between normal and abnormal cases, it is necessary to model changes in brain morphology owing to normal aging. To this end, we developed a method for analyzing and visualizing these changes for the entire brain morphology distribution in the general aging population. The method is applied to 1000 subjects from a large population imaging study in the elderly, from which 900 were used to train the model and 100 were used for testing. The results of the 100 test subjects show that the model generalizes to subjects outside the model population. Smooth percentile curves showing the brain morphology changes as a function of age and spatiotemporal atlases derived from the model population are publicly available via an interactive web application at agingbrain.bigr.nl.

  3. A general maximum likelihood analysis of variance components in generalized linear models.

    Science.gov (United States)

    Aitkin, M

    1999-03-01

    This paper describes an EM algorithm for nonparametric maximum likelihood (ML) estimation in generalized linear models with variance component structure. The algorithm provides an alternative analysis to approximate MQL and PQL analyses (McGilchrist and Aisbett, 1991, Biometrical Journal 33, 131-141; Breslow and Clayton, 1993; Journal of the American Statistical Association 88, 9-25; McGilchrist, 1994, Journal of the Royal Statistical Society, Series B 56, 61-69; Goldstein, 1995, Multilevel Statistical Models) and to GEE analyses (Liang and Zeger, 1986, Biometrika 73, 13-22). The algorithm, first given by Hinde and Wood (1987, in Longitudinal Data Analysis, 110-126), is a generalization of that for random effect models for overdispersion in generalized linear models, described in Aitkin (1996, Statistics and Computing 6, 251-262). The algorithm is initially derived as a form of Gaussian quadrature assuming a normal mixing distribution, but with only slight variation it can be used for a completely unknown mixing distribution, giving a straightforward method for the fully nonparametric ML estimation of this distribution. This is of value because the ML estimates of the GLM parameters can be sensitive to the specification of a parametric form for the mixing distribution. The nonparametric analysis can be extended straightforwardly to general random parameter models, with full NPML estimation of the joint distribution of the random parameters. This can produce substantial computational saving compared with full numerical integration over a specified parametric distribution for the random parameters. A simple method is described for obtaining correct standard errors for parameter estimates when using the EM algorithm. Several examples are discussed involving simple variance component and longitudinal models, and small-area estimation.

  4. Generalized eigenstate typicality in translation-invariant quasifree fermionic models

    Science.gov (United States)

    Riddell, Jonathon; Müller, Markus P.

    2018-01-01

    We demonstrate a generalized notion of eigenstate thermalization for translation-invariant quasifree fermionic models: the vast majority of eigenstates satisfying a finite number of suitable constraints (e.g., fixed energy and particle number) have the property that their reduced density matrix on small subsystems approximates the corresponding generalized Gibbs ensemble. To this end, we generalize analytic results by H. Lai and K. Yang [Phys. Rev. B 91, 081110(R) (2015), 10.1103/PhysRevB.91.081110] and illustrate the claim numerically by example of the Jordan-Wigner transform of the XX spin chain.

  5. A general diagnostic model applied to language testing data.

    Science.gov (United States)

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

  6. GPs' knowledge, use, and confidence in national physical activity and health guidelines and tools: a questionnaire-based survey of general practice in England.

    Science.gov (United States)

    Chatterjee, Robin; Chapman, Tim; Brannan, Mike Gt; Varney, Justin

    2017-10-01

    Physical activity (PA) brief advice in health care is effective at getting individuals active. It has been suggested that one in four people would be more active if advised by a GP or nurse, but as many as 72% of GPs do not discuss the benefits of physical activity with patients. To assess the knowledge, use, and confidence in national PA and Chief Medical Officer (CMO) health guidelines and tools among GPs in England. Online questionnaire-based survey of self-selecting GPs in England that took place over a 10-day period in March 2016. The questionnaire consisted of six multiple-choice questions and was available on the Doctors.net.uk (DNUK) homepage. Quotas were used to ensure good regional representation. The final analysis included 1013 responses. Only 20% of responders were broadly or very familiar with the national PA guidelines. In all, 70% of GPs were aware of the General Practice Physical Activity Questionnaire (GPPAQ), but 26% were not familiar with any PA assessment tools, and 55% reported that they had not undertaken any training with respect to encouraging PA. The majority of GPs in England (80%) are unfamiliar with the national PA guidelines. Awareness of the recommended tool for assessment, GPPAQ, is higher than use by GPs. This may be because it is used by other clinical staff, for example, as part of the NHS Health Check programme. Although brief advice in isolation by GPs on PA will only be a part of the behaviour change journey, it is an important prompt, especially if repeated as part of routine practice. This study highlights the need for significant improvement in knowledge, skills, and confidence to maximise the potential for PA advice in GP consultations. © British Journal of General Practice 2017.

  7. Dynamic generalized linear models for monitoring endemic diseases

    DEFF Research Database (Denmark)

    Lopes Antunes, Ana Carolina; Jensen, Dan; Hisham Beshara Halasa, Tariq

    2016-01-01

    The objective was to use a Dynamic Generalized Linear Model (DGLM) based on abinomial distribution with a linear trend, for monitoring the PRRS (Porcine Reproductive and Respiratory Syndrome sero-prevalence in Danish swine herds. The DGLM was described and its performance for monitoring control...... in sero-prevalence. Based on this, it was possible to detect variations in the growth model component. This study is a proof-of-concept, demonstrating the use of DGLMs for monitoring endemic diseases. In addition, the principles stated might be useful in general research on monitoring and surveillance...

  8. Voluntary reporting of greenhouse gases under Section 1605(b) of the Energy Policy Act of 1992: General Guidelines

    International Nuclear Information System (INIS)

    1994-10-01

    Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, Congress authorized a voluntary program for the public to report achievements in reducing those gases. This document offers guidance on recording historic and current greenhouse gas emissions, emissions reductions, and carbon sequestration. Under the Energy Policy Act (EPAct) reporters will have the opportunity to highlight specific achievements. If you have taken actions to lessen the greenhouse gas effect, either by decreasing greenhouse gas emissions or by sequestering carbon, the Department of Energy (DOE) encourages you to report your achievements under this program. The program has two related, but distinct parts. First, the program offers you an opportunity to report your annual emissions of greenhouse gases. Second, the program records your specific projects to reduce greenhouse gas emissions and increase carbon sequestration. Although participants in the program are strongly encouraged to submit reports on both, reports on either annual emissions or emissions reductions and carbon sequestration projects will be accepted. These guidelines and the supporting technical documents outline the rationale for the program and approaches to analyzing emissions and emissions reduction projects. Your annual emissions and emissions reductions achievements will be reported

  9. Generalized memory associativity in a network model for the neuroses

    Science.gov (United States)

    Wedemann, Roseli S.; Donangelo, Raul; de Carvalho, Luís A. V.

    2009-03-01

    We review concepts introduced in earlier work, where a neural network mechanism describes some mental processes in neurotic pathology and psychoanalytic working-through, as associative memory functioning, according to the findings of Freud. We developed a complex network model, where modules corresponding to sensorial and symbolic memories interact, representing unconscious and conscious mental processes. The model illustrates Freud's idea that consciousness is related to symbolic and linguistic memory activity in the brain. We have introduced a generalization of the Boltzmann machine to model memory associativity. Model behavior is illustrated with simulations and some of its properties are analyzed with methods from statistical mechanics.

  10. Seasonal predictability of Kiremt rainfall in coupled general circulation models

    Science.gov (United States)

    Gleixner, Stephanie; Keenlyside, Noel S.; Demissie, Teferi D.; Counillon, François; Wang, Yiguo; Viste, Ellen

    2017-11-01

    The Ethiopian economy and population is strongly dependent on rainfall. Operational seasonal predictions for the main rainy season (Kiremt, June-September) are based on statistical approaches with Pacific sea surface temperatures (SST) as the main predictor. Here we analyse dynamical predictions from 11 coupled general circulation models for the Kiremt seasons from 1985-2005 with the forecasts starting from the beginning of May. We find skillful predictions from three of the 11 models, but no model beats a simple linear prediction model based on the predicted Niño3.4 indices. The skill of the individual models for dynamically predicting Kiremt rainfall depends on the strength of the teleconnection between Kiremt rainfall and concurrent Pacific SST in the models. Models that do not simulate this teleconnection fail to capture the observed relationship between Kiremt rainfall and the large-scale Walker circulation.

  11. Estimating classification images with generalized linear and additive models.

    Science.gov (United States)

    Knoblauch, Kenneth; Maloney, Laurence T

    2008-12-22

    Conventional approaches to modeling classification image data can be described in terms of a standard linear model (LM). We show how the problem can be characterized as a Generalized Linear Model (GLM) with a Bernoulli distribution. We demonstrate via simulation that this approach is more accurate in estimating the underlying template in the absence of internal noise. With increasing internal noise, however, the advantage of the GLM over the LM decreases and GLM is no more accurate than LM. We then introduce the Generalized Additive Model (GAM), an extension of GLM that can be used to estimate smooth classification images adaptively. We show that this approach is more robust to the presence of internal noise, and finally, we demonstrate that GAM is readily adapted to estimation of higher order (nonlinear) classification images and to testing their significance.

  12. Automation of electroweak NLO corrections in general models

    Energy Technology Data Exchange (ETDEWEB)

    Lang, Jean-Nicolas [Universitaet Wuerzburg (Germany)

    2016-07-01

    I discuss the automation of generation of scattering amplitudes in general quantum field theories at next-to-leading order in perturbation theory. The work is based on Recola, a highly efficient one-loop amplitude generator for the Standard Model, which I have extended so that it can deal with general quantum field theories. Internally, Recola computes off-shell currents and for new models new rules for off-shell currents emerge which are derived from the Feynman rules. My work relies on the UFO format which can be obtained by a suited model builder, e.g. FeynRules. I have developed tools to derive the necessary counterterm structures and to perform the renormalization within Recola in an automated way. I describe the procedure using the example of the two-Higgs-doublet model.

  13. Improved Generalized Force Model considering the Comfortable Driving Behavior

    Directory of Open Access Journals (Sweden)

    De-Jie Xu

    2015-01-01

    Full Text Available This paper presents an improved generalized force model (IGFM that considers the driver’s comfortable driving behavior. Through theoretical analysis, we propose the calculation methods of comfortable driving distance and velocity. Then the stability condition of the model is obtained by the linear stability analysis. The problems of the unrealistic acceleration of the leading car existing in the previous models were solved. Furthermore, the simulation results show that IGFM can predict correct delay time of car motion and kinematic wave speed at jam density, and it can exactly describe the driver’s behavior under an urgent case, where no collision occurs. The dynamic properties of IGFM also indicate that stability has improved compared to the generalized force model.

  14. Involving migrants in the development of guidelines for communication in cross-cultural general practice consultations: a participatory learning and action research project.

    Science.gov (United States)

    O'Reilly-de Brún, Mary; MacFarlane, Anne; de Brún, Tomas; Okonkwo, Ekaterina; Bonsenge Bokanga, Jean Samuel; Manuela De Almeida Silva, Maria; Ogbebor, Florence; Mierzejewska, Aga; Nnadi, Lovina; van den Muijsenbergh, Maria; van Weel-Baumgarten, Evelyn; van Weel, Chris

    2015-09-21

    The aim of this research was to involve migrants and other key stakeholders in a participatory dialogue to develop a guideline for enhancing communication in cross-cultural general practice consultations. In this paper, we focus on findings about the use of formal versus informal interpreters because dialogues about these issues emerged as central to the identification of recommendations for best practice. This qualitative case study involved a Participatory Learning and Action (PLA) research methodology. The sample comprised 80 stakeholders: 51 from migrant communities; 15 general practitioners (GPs) and general practice staff; 7 established migrants as peer researchers; 5 formal, trained interpreters; and 2 service planners from the national health authority. Galway, Ireland. There was 100% consensus across stakeholder groups that while informal interpreters have uses for migrants and general practice staff, they are not considered acceptable as best practice. There was also 100% consensus that formal interpreters who are trained and working as per a professional code of practice are acceptable as best practice. Policymakers and service planners need to work in partnership with service providers and migrants to progress the implementation of professional, trained interpreters as a routine way of working in general practice. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. A general model framework for multisymbol number comparison.

    Science.gov (United States)

    Huber, Stefan; Nuerk, Hans-Christoph; Willmes, Klaus; Moeller, Korbinian

    2016-11-01

    Different models have been proposed for the processing of multisymbol numbers like two- and three-digit numbers but also for negative numbers and decimals. However, these multisymbol numbers are assembled from the same set of Arabic digits and comply with the place-value structure of the Arabic number system. Considering these shared properties, we suggest that the processing of multisymbol numbers can be described in one general model framework. Accordingly, we first developed a computational model framework realizing componential representations of multisymbol numbers and evaluated its validity by simulating standard empirical effects of number magnitude comparison. We observed that the model framework successfully accounted for most of these effects. Moreover, our simulations provided first evidence supporting the notion of a fully componential processing of multisymbol numbers for the specific case of comparing two negative numbers. Thus, our general model framework indicates that the processing of different kinds of multisymbol integer and decimal numbers shares common characteristics (e.g., componential representation). The relevance and applicability of our model goes beyond the case of basic number processing. In particular, we also successfully simulated effects from applied marketing and consumer research by accounting for the left-digit effect found in processing of prices. Finally, we provide evidence that our model framework can be integrated into the more general context of multiattribute decision making. In sum, this indicates that our model framework captures a general scheme of separate processing of different attributes weighted by their saliency for the task at hand. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. SELECTION MOMENTS AND GENERALIZED METHOD OF MOMENTS FOR HETEROSKEDASTIC MODELS

    Directory of Open Access Journals (Sweden)

    Constantin ANGHELACHE

    2016-06-01

    Full Text Available In this paper, the authors describe the selection methods for moments and the application of the generalized moments method for the heteroskedastic models. The utility of GMM estimators is found in the study of the financial market models. The selection criteria for moments are applied for the efficient estimation of GMM for univariate time series with martingale difference errors, similar to those studied so far by Kuersteiner.

  17. Contextual interactions in a generalized energy model of complex cells

    OpenAIRE

    Dellen, Babette; Clark, John W.; Wessel, Ralf

    2009-01-01

    We propose a generalized energy model of complex cells to describe modulatory contextual influences on the responses of neurons in the primary visual cortex (V1). Many orientationselective cells in V1 respond to contrast of orientation and motion of stimuli exciting the classical receptive field (CRF) and the non-CRF, or surround. In the proposed model, a central spatiotemporal filter, defining the CRF, is nonlinearly combined with a spatiotemporal filter extending into the non- ...

  18. Study of the properties of general relativistic Kink model (GRK)

    International Nuclear Information System (INIS)

    Oliveira, L.C.S. de.

    1980-01-01

    The stability of the general relativistic Kink model (GRK) is studied. It is shown that the model is stable at least against radial perturbations. Furthermore, the Dirac field in the background of the geometry generated by the GRK is studied. It is verified that the GRK localizes the Dirac field, around the region of largest curvature. The physical interpretation of this system (the Dirac field in the GRK background) is discussed. (Author) [pt

  19. On the Use of Generalized Volume Scattering Models for the Improvement of General Polarimetric Model-Based Decomposition

    Directory of Open Access Journals (Sweden)

    Qinghua Xie

    2017-01-01

    Full Text Available Recently, a general polarimetric model-based decomposition framework was proposed by Chen et al., which addresses several well-known limitations in previous decomposition methods and implements a simultaneous full-parameter inversion by using complete polarimetric information. However, it only employs four typical models to characterize the volume scattering component, which limits the parameter inversion performance. To overcome this issue, this paper presents two general polarimetric model-based decomposition methods by incorporating the generalized volume scattering model (GVSM or simplified adaptive volume scattering model, (SAVSM proposed by Antropov et al. and Huang et al., respectively, into the general decomposition framework proposed by Chen et al. By doing so, the final volume coherency matrix structure is selected from a wide range of volume scattering models within a continuous interval according to the data itself without adding unknowns. Moreover, the new approaches rely on one nonlinear optimization stage instead of four as in the previous method proposed by Chen et al. In addition, the parameter inversion procedure adopts the modified algorithm proposed by Xie et al. which leads to higher accuracy and more physically reliable output parameters. A number of Monte Carlo simulations of polarimetric synthetic aperture radar (PolSAR data are carried out and show that the proposed method with GVSM yields an overall improvement in the final accuracy of estimated parameters and outperforms both the version using SAVSM and the original approach. In addition, C-band Radarsat-2 and L-band AIRSAR fully polarimetric images over the San Francisco region are also used for testing purposes. A detailed comparison and analysis of decomposition results over different land-cover types are conducted. According to this study, the use of general decomposition models leads to a more accurate quantitative retrieval of target parameters. However, there

  20. Review of guidance on recurrence risk management for general practitioners in breast cancer, colorectal cancer and melanoma guidelines.

    NARCIS (Netherlands)

    Spronk, I.; Korevaar, J.C.; Burgers, J.S.; Albreht, T.; Schellevis, F.G.

    2017-01-01

    Background. General practitioners (GPs) will face cancer recurrences more frequently due to the rising number of cancer survivors and greater involvement of GPs in the follow-up care. Currently, GPs are uncertain about managing recurrence risks and may need more guidance. Objective. To explore what

  1. A formal approach to the analysis of clinical computer-interpretable guideline modeling languages.

    Science.gov (United States)

    Grando, M Adela; Glasspool, David; Fox, John

    2012-01-01

    To develop proof strategies to formally study the expressiveness of workflow-based languages, and to investigate their applicability to clinical computer-interpretable guideline (CIG) modeling languages. We propose two strategies for studying the expressiveness of workflow-based languages based on a standard set of workflow patterns expressed as Petri nets (PNs) and notions of congruence and bisimilarity from process calculus. Proof that a PN-based pattern P can be expressed in a language L can be carried out semi-automatically. Proof that a language L cannot provide the behavior specified by a PNP requires proof by exhaustion based on analysis of cases and cannot be performed automatically. The proof strategies are generic but we exemplify their use with a particular CIG modeling language, PROforma. To illustrate the method we evaluate the expressiveness of PROforma against three standard workflow patterns and compare our results with a previous similar but informal comparison. We show that the two proof strategies are effective in evaluating a CIG modeling language against standard workflow patterns. We find that using the proposed formal techniques we obtain different results to a comparable previously published but less formal study. We discuss the utility of these analyses as the basis for principled extensions to CIG modeling languages. Additionally we explain how the same proof strategies can be reused to prove the satisfaction of patterns expressed in the declarative language CIGDec. The proof strategies we propose are useful tools for analysing the expressiveness of CIG modeling languages. This study provides good evidence of the benefits of applying formal methods of proof over semi-formal ones. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. The general class of Bianchi cosmological models with dark energy ...

    Indian Academy of Sciences (India)

    The general class of Bianchi cosmological models with dark energy in the form of modified Chaplygin gas with variable Λ and G and bulk viscosity have been considered. We discuss three types of average scalefactor by using a special law for deceleration parameter which is linear in time with negative slope. The exact ...

  3. A general circulation model (GCM) parameterization of Pinatubo aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Lacis, A.A.; Carlson, B.E.; Mishchenko, M.I. [NASA Goddard Institute for Space Studies, New York, NY (United States)

    1996-04-01

    The June 1991 volcanic eruption of Mt. Pinatubo is the largest and best documented global climate forcing experiment in recorded history. The time development and geographical dispersion of the aerosol has been closely monitored and sampled. Based on preliminary estimates of the Pinatubo aerosol loading, general circulation model predictions of the impact on global climate have been made.

  4. A generalized quarter car modelling approach with frame flexibility ...

    Indian Academy of Sciences (India)

    HUSAIN KANCHWALA

    ground-wheel contacts at three other locations. A Matlab code for obtaining the generalized quarter-car model is provided towards the end of this paper. The code enables a user to perform fairly quick parametric studies. An example of such a parametric study is presented there as well. The role of other wheels, in particular, ...

  5. Anisotropic cosmological models and generalized scalar tensor theory

    Indian Academy of Sciences (India)

    Abstract. In this paper generalized scalar tensor theory has been considered in the background of anisotropic cosmological models, namely, axially symmetric Bianchi-I, Bianchi-III and Kortowski–. Sachs space-time. For bulk viscous fluid, both exponential and power-law solutions have been stud- ied and some assumptions ...

  6. Anisotropic cosmological models and generalized scalar tensor theory

    Indian Academy of Sciences (India)

    In this paper generalized scalar tensor theory has been considered in the background of anisotropic cosmological models, namely, axially symmetric Bianchi-I, Bianchi-III and Kortowski–Sachs space-time. For bulk viscous fluid, both exponential and power-law solutions have been studied and some assumptions among the ...

  7. Transmittivity and wavefunctions in one-dimensional generalized Aubry models

    International Nuclear Information System (INIS)

    Basu, C.; Mookerjee, A.; Sen, A.K.; Thakur, P.K.

    1990-07-01

    We use the vector recursion method of Haydock to obtain the transmittance of a class of generalized Aubry models in one-dimension. We also study the phase change of the wavefunctions as they travel through the chain and also the behaviour of the conductance with changes in size. (author). 10 refs, 9 figs

  8. Characterizing QALYs under a General Rank Dependent Utility Model

    NARCIS (Netherlands)

    H. Bleichrodt (Han); J. Quiggin (John)

    1997-01-01

    textabstractThis paper provides a characterization of QALYs, the most important outcome measure in medical decision making, in the context of a general rank dependent utility model. We show that both for chronic and for nonchronic health states the characterization of QALYs depends on intuitive

  9. Model-free adaptive sliding mode controller design for generalized ...

    Indian Academy of Sciences (India)

    L M WANG

    2017-08-16

    Aug 16, 2017 ... Abstract. A novel model-free adaptive sliding mode strategy is proposed for a generalized projective synchronization (GPS) between two entirely unknown fractional-order chaotic systems subject to the external disturbances. To solve the difficulties from the little knowledge about the master–slave system ...

  10. Simplicial models for trace spaces II: General higher dimensional automata

    DEFF Research Database (Denmark)

    Raussen, Martin

    Higher Dimensional Automata (HDA) are topological models for the study of concurrency phenomena. The state space for an HDA is given as a pre-cubical complex in which a set of directed paths (d-paths) is singled out. The aim of this paper is to describe a general method that determines the space...

  11. An applied general equilibrium model for Dutch agribusiness policy analysis

    NARCIS (Netherlands)

    Peerlings, J.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of

  12. Confidence Intervals for Assessing Heterogeneity in Generalized Linear Mixed Models

    Science.gov (United States)

    Wagler, Amy E.

    2014-01-01

    Generalized linear mixed models are frequently applied to data with clustered categorical outcomes. The effect of clustering on the response is often difficult to practically assess partly because it is reported on a scale on which comparisons with regression parameters are difficult to make. This article proposes confidence intervals for…

  13. Bianchi type-V string cosmological models in general relativity

    Indian Academy of Sciences (India)

    Abstract. Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's field equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's field equations are solvable for any arbitrary ...

  14. A generalized quarter car modelling approach with frame flexibility ...

    Indian Academy of Sciences (India)

    ... mass distribution and damping. Here we propose a generalized quarter-car modelling approach, incorporating both the frame as well as other-wheel ground contacts. Our approach is linear, uses Laplace transforms, involves vertical motions of key points of interest and has intermediate complexity with improved realism.

  15. On the general procedure for modelling complex ecological systems

    International Nuclear Information System (INIS)

    He Shanyu.

    1987-12-01

    In this paper, the principle of a general procedure for modelling complex ecological systems, i.e. the Adaptive Superposition Procedure (ASP) is shortly stated. The result of application of ASP in a national project for ecological regionalization is also described. (author). 3 refs

  16. Bianchi type-V string cosmological models in general relativity

    Indian Academy of Sciences (India)

    Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's field equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's field equations are solvable for any arbitrary cosmic scale ...

  17. Uncertainty in a monthly water balance model using the generalized ...

    Indian Academy of Sciences (India)

    Uncertainty in a monthly water balance model using the generalized likelihood uncertainty estimation methodology. Diego Rivera1,∗. , Yessica Rivas. 2 and Alex Godoy. 3. 1. Laboratory of Comparative Policy in Water Resources Management, University of Concepcion,. CONICYT/FONDAP 15130015, Concepcion, Chile. 2.

  18. Towards a Conceptual Model for Enhancing Reasoning about Clinical Guidelines: A case-study on Comorbidity

    NARCIS (Netherlands)

    Carretta Zamborlini, Veruska; Da Silveira, Marcos; Pruski, Cedric; ten Teije, Annette; van Harmelen, Frank

    2014-01-01

    Computer-Interpretable Guidelines (CIGs) are representations of Clinical Guidelines (CGs) in computer interpretable languages. CIGs have been pointed as an alternative to deal with the various limitations of paper based CGs to support healthcare activities. Although the improvements offered by

  19. Reporting guidelines for diagnostic accuracy studies that use Bayesian latent class models (STARD-BLCM)

    DEFF Research Database (Denmark)

    Kostoulas, Polychronis; Nielsen, Søren S.; Branscum, Adam J.

    2017-01-01

    Evaluation of medical tests is usually based on comparing their results to those from a perfect reference (gold standard) procedure. The Standards for Reporting of Diagnostic Accuracy (STARD) initiative (http://www.equator-network.org/reporting-guidelines/stard/) developed reporting guidelines...

  20. Analysis of snow feedbacks in 14 general circulation models

    Science.gov (United States)

    Randall, D. A.; Cess, R. D.; Blanchet, J. P.; Chalita, S.; Colman, R.; Dazlich, D. A.; Del Genio, A. D.; Keup, E.; Lacis, A.; Le Treut, H.; Liang, X.-Z.; McAvaney, B. J.; Mahfouf, J. F.; Meleshko, V. P.; Morcrette, J.-J.; Norris, P. M.; Potter, G. L.; Rikus, L.; Roeckner, E.; Royer, J. F.; Schlese, U.; Sheinin, D. A.; Sokolov, A. P.; Taylor, K. E.; Wetherald, R. T.; Yagai, I.; Zhang, M.-H.

    1994-10-01

    Snow feedbacks produced by 14 atmospheric general circulation models have been analyzed through idealized numerical experiments. Included in the analysis is an investigation of the surface energy budgets of the models. Negative or weak positive snow feedbacks occurred in some of the models, while others produced strong positive snow feedbacks. These feedbacks are due not only to melting snow, but also to increases in boundary temperature, changes in air temperature, changes in water vapor, and changes in cloudiness. As a result, the net response of each model is quite complex. We analyze in detail the responses of one model with a strong positive snow feedback and another with a weak negative snow feedback. Some of the models include a temperature dependence of the snow albedo, and this has significantly affected the results.

  1. The establishment of MELCOR/SNAP model of Chinshan nuclear power plant for Ultimate Response Guideline

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Wen-Sheng, E-mail: wshsu@ess.nthu.edu.tw [Nuclear Science and Technology Development Center, Institute of Nuclear Engineering and Science, National Tsing Hua University, Nuclear and New Energy Education and Research Foundation, No. 101, Section 2, Kuang Fu Rd., HsinChu 30013, Taiwan, ROC (China); Chiang, Yu, E-mail: s101013702@m101.nthu.edu.tw [Nuclear Science and Technology Development Center, Institute of Nuclear Engineering and Science, National Tsing Hua University, Nuclear and New Energy Education and Research Foundation, No. 101, Section 2, Kuang Fu Rd., HsinChu 30013, Taiwan, ROC (China); Wang, Jong-Rong, E-mail: jongrongwang@gmail.com [Nuclear Science and Technology Development Center, Institute of Nuclear Engineering and Science, National Tsing Hua University, Nuclear and New Energy Education and Research Foundation, No. 101, Section 2, Kuang Fu Rd., HsinChu 30013, Taiwan, ROC (China); Wang, Ting-Yi, E-mail: minired1119@gmail.com [Nuclear Science and Technology Development Center, Institute of Nuclear Engineering and Science, National Tsing Hua University, Nuclear and New Energy Education and Research Foundation, No. 101, Section 2, Kuang Fu Rd., HsinChu 30013, Taiwan, ROC (China); Wang, Te-Chuan, E-mail: tcwang@iner.gov.tw [Institute of Nuclear Energy Research Atomic Energy Council, R.O.C., 1000, Wenhua Road Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China); Teng, Jyh-Tong, E-mail: jyhtong@cycu.edu.tw [Department of Mechanical Engineering, Chung Yuan Christian University, 200, Chung Pei Rd, Chung Li 32023, Taiwan, ROC (China); Chen, Shao-Wen, E-mail: chensw@mx.nthu.edu.tw [Nuclear Science and Technology Development Center, Institute of Nuclear Engineering and Science, National Tsing Hua University, Nuclear and New Energy Education and Research Foundation, No. 101, Section 2, Kuang Fu Rd., HsinChu 30013, Taiwan, ROC (China); and others

    2017-01-15

    Highlights: • The establishment of a MELCOR/SNAP model of Chinshan (BWR/4). • MELCOR/SNAP model was used to estimate the effectiveness of URG for Chinshan. • The MELCOR results were compared to MAAP, TRACE and PCTRAN. • URG is a new method to prevent a Fukushima-like accident. • The low raw water (150 GPM) can make the cladding temperature below 1088.7 K. - Abstract: After Fukushima Daiichi disaster, the safety analysis of severe accidents became one of the safety concerns in Taiwan. The Emergency Operating Procedure (EOP) cannot cope with a multiple system failure situation under a severe accident since it is a “Symptom-basis” procedure. To deal with that, Taiwan Power Company built up a new strategy for Fukushima-like accident called Ultimate Response Guideline (URG). It is a simple strategy with three main conditions: loss of regular motor driven injection system, loss of all AC power and tsunami/earthquake warning. If two of three happen, the operating procedure will change from EOP to URG and start the main works by following the strategy. There are three main works in URG: controlled-depressurization, line up low pressure injection water and prepare containment venting. In this study, MELCOR2.1 was used to calculate the cases of URG and checked the goal of the strategy that prevents the accident or not. There were three steps in this research. First, a model of Chinshan nuclear power plant (NPP) was built. Second, one was the case with URG and the other was not by using the above MELCOR model. The results were compared to MAAP5.0, TRACE and PCTRAN. Finally, some sensitivity studies of depressurization and water injection rate were done.

  2. Generalized Chaplygin gas model, supernovae, and cosmic topology

    International Nuclear Information System (INIS)

    Bento, M.C.; Bertolami, O.; Silva, P.T.; Reboucas, M.J.

    2006-01-01

    In this work we study to which extent the knowledge of spatial topology may place constraints on the parameters of the generalized Chaplygin gas (GCG) model for unification of dark energy and dark matter. By using both the Poincare dodecahedral and binary octahedral spaces as the observable spatial topologies, we examine the current type Ia supernovae (SNe Ia) constraints on the GCG model parameters. We show that the knowledge of spatial topology does provide additional constraints on the A s parameter of the GCG model but does not lift the degeneracy of the α parameter

  3. Generalized Roe's numerical scheme for a two-fluid model

    International Nuclear Information System (INIS)

    Toumi, I.; Raymond, P.

    1993-01-01

    This paper is devoted to a mathematical and numerical study of a six equation two-fluid model. We will prove that the model is strictly hyperbolic due to the inclusion of the virtual mass force term in the phasic momentum equations. The two-fluid model is naturally written under a nonconservative form. To solve the nonlinear Riemann problem for this nonconservative hyperbolic system, a generalized Roe's approximate Riemann solver, is used, based on a linearization of the nonconservative terms. A Godunov type numerical scheme is built, using this approximate Riemann solver. 10 refs., 5 figs,

  4. Holographic entanglement entropy in general holographic superconductor models

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yan [School of Mathematics and Computer Science, Shaanxi University of Technology,Hanzhong, Shaanxi 723000 (China); Pan, Qiyuan [Institute of Physics and Department of Physics, Hunan Normal University,Changsha, Hunan 410081 (China)

    2014-06-03

    We study the entanglement entropy of general holographic dual models both in AdS soliton and AdS black hole backgrounds with full backreaction. We find that the entanglement entropy is a good probe to explore the properties of the holographic superconductors and provides richer physics in the phase transition. We obtain the effects of the scalar mass, model parameter and backreaction on the entropy, and argue that the jump of the entanglement entropy may be a quite general feature for the first order phase transition. In strong contrast to the insulator/superconductor system, we note that the backreaction coupled with the scalar mass can not be used to trigger the first order phase transition if the model parameter is below its bottom bound in the metal/superconductor system.

  5. Commensurate Priors for Incorporating Historical Information in Clinical Trials Using General and Generalized Linear Models

    Science.gov (United States)

    Hobbs, Brian P.; Sargent, Daniel J.; Carlin, Bradley P.

    2014-01-01

    Assessing between-study variability in the context of conventional random-effects meta-analysis is notoriously difficult when incorporating data from only a small number of historical studies. In order to borrow strength, historical and current data are often assumed to be fully homogeneous, but this can have drastic consequences for power and Type I error if the historical information is biased. In this paper, we propose empirical and fully Bayesian modifications of the commensurate prior model (Hobbs et al., 2011) extending Pocock (1976), and evaluate their frequentist and Bayesian properties for incorporating patient-level historical data using general and generalized linear mixed regression models. Our proposed commensurate prior models lead to preposterior admissible estimators that facilitate alternative bias-variance trade-offs than those offered by pre-existing methodologies for incorporating historical data from a small number of historical studies. We also provide a sample analysis of a colon cancer trial comparing time-to-disease progression using a Weibull regression model. PMID:24795786

  6. Towards a generalized energy prediction model for machine tools.

    Science.gov (United States)

    Bhinge, Raunak; Park, Jinkyoo; Law, Kincho H; Dornfeld, David A; Helu, Moneer; Rachuri, Sudarsan

    2017-04-01

    Energy prediction of machine tools can deliver many advantages to a manufacturing enterprise, ranging from energy-efficient process planning to machine tool monitoring. Physics-based, energy prediction models have been proposed in the past to understand the energy usage pattern of a machine tool. However, uncertainties in both the machine and the operating environment make it difficult to predict the energy consumption of the target machine reliably. Taking advantage of the opportunity to collect extensive, contextual, energy-consumption data, we discuss a data-driven approach to develop an energy prediction model of a machine tool in this paper. First, we present a methodology that can efficiently and effectively collect and process data extracted from a machine tool and its sensors. We then present a data-driven model that can be used to predict the energy consumption of the machine tool for machining a generic part. Specifically, we use Gaussian Process (GP) Regression, a non-parametric machine-learning technique, to develop the prediction model. The energy prediction model is then generalized over multiple process parameters and operations. Finally, we apply this generalized model with a method to assess uncertainty intervals to predict the energy consumed to machine any part using a Mori Seiki NVD1500 machine tool. Furthermore, the same model can be used during process planning to optimize the energy-efficiency of a machining process.

  7. The Eatwell Guide: Modelling the Health Implications of Incorporating New Sugar and Fibre Guidelines.

    Directory of Open Access Journals (Sweden)

    Linda J Cobiac

    Full Text Available To model population health impacts of dietary changes associated with the redevelopment of the UK food-based dietary guidelines (the 'Eatwell Guide'.Using multi-state lifetable methods, we modelled the impact of dietary changes on cardiovascular disease, diabetes and cancers over the lifetime of the current UK population. From this model, we determined change in life expectancy and disability-adjusted life years (DALYs that could be averted.Changing the average diet to that recommended in the new Eatwell Guide, without increasing total energy intake, could increase average life expectancy by 5.4 months (95% uncertainty interval: 4.7 to 6.2 for men and 4.0 months (3.4 to 4.6 for women; and avert 17.9 million (17.6 to 18.2 DALYs over the lifetime of the current population. A large proportion of the health benefits are from prevention of type 2 diabetes, with 440,000 (400,000 to 480,000 new cases prevented in men and 340,000 (310,000 to 370,000 new cases prevented in women, over the next ten years. Prevention of cardiovascular diseases and colorectal cancer is also large. However, if the diet recommended in the new Eatwell Guide is achieved with an accompanying increase in energy intake (and thus an increase in body mass index, around half the potential improvements in population health will not be realised.The dietary changes required to meet recommendations in the Eatwell Guide, which include eating more fruits and vegetables and less red and processed meats and dairy products, are large. However, the potential population health benefits are substantial.

  8. 2017 publication guidelines for structural modelling of small-angle scattering data from biomolecules in solution: an update.

    Science.gov (United States)

    Trewhella, Jill; Duff, Anthony P; Durand, Dominique; Gabel, Frank; Guss, J Mitchell; Hendrickson, Wayne A; Hura, Greg L; Jacques, David A; Kirby, Nigel M; Kwan, Ann H; Pérez, Javier; Pollack, Lois; Ryan, Timothy M; Sali, Andrej; Schneidman-Duhovny, Dina; Schwede, Torsten; Svergun, Dmitri I; Sugiyama, Masaaki; Tainer, John A; Vachette, Patrice; Westbrook, John; Whitten, Andrew E

    2017-09-01

    In 2012, preliminary guidelines were published addressing sample quality, data acquisition and reduction, presentation of scattering data and validation, and modelling for biomolecular small-angle scattering (SAS) experiments. Biomolecular SAS has since continued to grow and authors have increasingly adopted the preliminary guidelines. In parallel, integrative/hybrid determination of biomolecular structures is a rapidly growing field that is expanding the scope of structural biology. For SAS to contribute maximally to this field, it is essential to ensure open access to the information required for evaluation of the quality of SAS samples and data, as well as the validity of SAS-based structural models. To this end, the preliminary guidelines for data presentation in a publication are reviewed and updated, and the deposition of data and associated models in a public archive is recommended. These guidelines and recommendations have been prepared in consultation with the members of the International Union of Crystallography (IUCr) Small-Angle Scattering and Journals Commissions, the Worldwide Protein Data Bank (wwPDB) Small-Angle Scattering Validation Task Force and additional experts in the field.

  9. Surgery-first accelerated orthognathic surgery: orthodontic guidelines and setup for model surgery.

    Science.gov (United States)

    Liou, Eric J W; Chen, Po-Hsung; Wang, Yu-Chih; Yu, Chung-Chih; Huang, C S; Chen, Yu-Ray

    2011-03-01

    The surgery-first approach indicates that the orthognathic surgery precedes the orthodontic treatment, whereas the orthodontics-first approach indicates that the orthodontic treatment precedes the orthognathic surgery. The conventional approach is an orthodontics-first approach. The purposes of this article are to introduce the concept of the surgery-first approach and to report the guidelines for orthodontic management and model surgery without presurgical orthodontic decompensation. The surgery-first approach treats facial esthetics first and then occlusion, whereas the conventional approach treats occlusion first and then facial esthetics. The surgery-first approach uses osteotomy to solve both skeletal problems and dental compensation, and a "transitional" occlusion is set up postoperatively. Orthodontics in the surgery-first approach is a postoperatively adjunctive treatment to transfigure the transitional occlusion into the solid final occlusion. The advantages of the surgery-first approach are that 1) the patient's chief complaint, dental function, and facial esthetics are achieved and improved in the beginning of the treatment; 2) the entire treatment period is shortened to 1 to 1.5 years or fewer depending on the complexity of orthodontic treatment; and 3) the phenomenon of postoperatively accelerated orthodontic tooth movement reduces the difficulty and treatment time of orthodontic management in the surgery-first approach. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  10. Environmental quality model in centralised radiopharmacy units: Guidelines from French Society of Radiopharmacy

    International Nuclear Information System (INIS)

    Bruel, D.; Duez, C.; Ebel-Lao, S.; Garrigue, H.; Le Meur, C.

    2011-01-01

    The preparation of radiopharmaceutical drugs refers to the assessment of both pharmaceutical drugs and radionuclides preparations regulations. It should avoid microbiological contamination while ensuring staff as well as environmental protection from radioactive exposure. Therefore, in order to warranty sterility of injected doses, the environmental quality, specifically units indoor air quality and surfaces quality must be guaranteed. The aim of this work is to propose guidelines pertaining to environmental quality monitoring in the special field of radiopharmacy. These propositions are based on available guidances, including regulations, treating about methodology to apply for evaluation and control of hospital's environment. Throughout this report, the French College of Radiopharmacy proposals both improve the methodology for control and data analysis (targeted grade of environment, threshold for notification and corrective actions) and ensure follow-up and management of nonconformities. These recommendations represent a model for harmonization of radio-pharmacists practices with regards to frequency of environmental quality controls for facilities and equipments in their centralised radiopharmacy units. (authors)

  11. Generalized Modeling of the Human Lower Limb Assembly

    Science.gov (United States)

    Cofaru, Ioana; Huzu, Iulia

    2014-11-01

    The main reason for creating a generalized assembly of the main bones of the lower human member is to create the premises of realizing a biomechanic assisted study which could be used for the study of the high range of varieties of pathologies that exist at this level. Starting from 3D CAD models of the main bones of the lower human member, which were realized in previous researches, in this study a generalized assembly system was developed, system in which are highlighted both the situation of an healthy subject and the situation of the situation of a subject affected by axial deviations. In order to achieve these purpose reference systems were created, systems that are in accordance with the mechanical axes and the anatomic axes of the lower member, which were later generally assembled in a manner that provides an easy customization option

  12. Attractive Hubbard model with disorder and the generalized Anderson theorem

    International Nuclear Information System (INIS)

    Kuchinskii, E. Z.; Kuleeva, N. A.; Sadovskii, M. V.

    2015-01-01

    Using the generalized DMFT+Σ approach, we study the influence of disorder on single-particle properties of the normal phase and the superconducting transition temperature in the attractive Hubbard model. A wide range of attractive potentials U is studied, from the weak coupling region, where both the instability of the normal phase and superconductivity are well described by the BCS model, to the strong-coupling region, where the superconducting transition is due to Bose-Einstein condensation (BEC) of compact Cooper pairs, formed at temperatures much higher than the superconducting transition temperature. We study two typical models of the conduction band with semi-elliptic and flat densities of states, respectively appropriate for three-dimensional and two-dimensional systems. For the semi-elliptic density of states, the disorder influence on all single-particle properties (e.g., density of states) is universal for an arbitrary strength of electronic correlations and disorder and is due to only the general disorder widening of the conduction band. In the case of a flat density of states, universality is absent in the general case, but still the disorder influence is mainly due to band widening, and the universal behavior is restored for large enough disorder. Using the combination of DMFT+Σ and Nozieres-Schmitt-Rink approximations, we study the disorder influence on the superconducting transition temperature T c for a range of characteristic values of U and disorder, including the BCS-BEC crossover region and the limit of strong-coupling. Disorder can either suppress T c (in the weak-coupling region) or significantly increase T c (in the strong-coupling region). However, in all cases, the generalized Anderson theorem is valid and all changes of the superconducting critical temperature are essentially due to only the general disorder widening of the conduction band

  13. Penalized Estimation in Large-Scale Generalized Linear Array Models

    DEFF Research Database (Denmark)

    Lund, Adam; Vincent, Martin; Hansen, Niels Richard

    2017-01-01

    Large-scale generalized linear array models (GLAMs) can be challenging to fit. Computation and storage of its tensor product design matrix can be impossible due to time and memory constraints, and previously considered design matrix free algorithms do not scale well with the dimension of the para......Large-scale generalized linear array models (GLAMs) can be challenging to fit. Computation and storage of its tensor product design matrix can be impossible due to time and memory constraints, and previously considered design matrix free algorithms do not scale well with the dimension...... of the parameter vector. A new design matrix free algorithm is proposed for computing the penalized maximum likelihood estimate for GLAMs, which, in particular, handles nondifferentiable penalty functions. The proposed algorithm is implemented and available via the R package glamlasso. It combines several ideas...

  14. A Unified Bayesian Inference Framework for Generalized Linear Models

    Science.gov (United States)

    Meng, Xiangming; Wu, Sheng; Zhu, Jiang

    2018-03-01

    In this letter, we present a unified Bayesian inference framework for generalized linear models (GLM) which iteratively reduces the GLM problem to a sequence of standard linear model (SLM) problems. This framework provides new perspectives on some established GLM algorithms derived from SLM ones and also suggests novel extensions for some other SLM algorithms. Specific instances elucidated under such framework are the GLM versions of approximate message passing (AMP), vector AMP (VAMP), and sparse Bayesian learning (SBL). It is proved that the resultant GLM version of AMP is equivalent to the well-known generalized approximate message passing (GAMP). Numerical results for 1-bit quantized compressed sensing (CS) demonstrate the effectiveness of this unified framework.

  15. A Non-Gaussian Spatial Generalized Linear Latent Variable Model

    KAUST Repository

    Irincheeva, Irina

    2012-08-03

    We consider a spatial generalized linear latent variable model with and without normality distributional assumption on the latent variables. When the latent variables are assumed to be multivariate normal, we apply a Laplace approximation. To relax the assumption of marginal normality in favor of a mixture of normals, we construct a multivariate density with Gaussian spatial dependence and given multivariate margins. We use the pairwise likelihood to estimate the corresponding spatial generalized linear latent variable model. The properties of the resulting estimators are explored by simulations. In the analysis of an air pollution data set the proposed methodology uncovers weather conditions to be a more important source of variability than air pollution in explaining all the causes of non-accidental mortality excluding accidents. © 2012 International Biometric Society.

  16. The international endorsement of US distress screening and psychosocial guidelines in oncology: a model for dissemination.

    Science.gov (United States)

    Lazenby, Mark

    2014-02-01

    The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Distress Management have, since 1997, called for routine screening of distress in patients with cancer. Following the example of pain as the fifth vital sign, the case for using the concept of distress as the sixth vital sign was made by leading psycho-oncologists in 2007. Cancer care organizations in Canada and the International Psycho-Oncology Society have adopted the NCCN Guidelines for Distress Management and have named distress screening as the sixth vital sign, thereby encouraging cancer care clinicians to think of screening for distress when they screen for pain and other vital signs. Using the evidence integration triangle, this article explores the dissemination of the notion of distress as the sixth vital sign in an international context. This exploration shows that NCCN and similar organizations can adopt the evidence integration triangle in its next phase of moving toward full implementation of the NCCN Guidelines for Distress Management.

  17. Treatment of cloud radiative effects in general circulation models

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.C.; Dudek, M.P.; Liang, X.Z.; Ding, M. [State Univ. of New York, Albany, NY (United States)] [and others

    1996-04-01

    We participate in the Atmospheric Radiation Measurement (ARM) program with two objectives: (1) to improve the general circulation model (GCM) cloud/radiation treatment with a focus on cloud verticle overlapping and layer cloud optical properties, and (2) to study the effects of cloud/radiation-climate interaction on GCM climate simulations. This report summarizes the project progress since the Fourth ARM Science Team meeting February 28-March 4, 1994, in Charleston, South Carolina.

  18. Generalized isothermal models with strange equation of state

    Indian Academy of Sciences (India)

    intention to study the Einstein–Maxwell system with a linear equation of state with ... It is our intention to model the interior of a dense realistic star with a general ... The definition m(r) = 1. 2. ∫ r. 0 ω2ρ(ω)dω. (14) represents the mass contained within a radius r which is a useful physical quantity. The mass function (14) has ...

  19. Classification images and bubbles images in the generalized linear model.

    Science.gov (United States)

    Murray, Richard F

    2012-07-09

    Classification images and bubbles images are psychophysical tools that use stimulus noise to investigate what features people use to make perceptual decisions. Previous work has shown that classification images can be estimated using the generalized linear model (GLM), and here I show that this is true for bubbles images as well. Expressing the two approaches in terms of a single statistical model clarifies their relationship to one another, makes it possible to measure classification images and bubbles images simultaneously, and allows improvements developed for one method to be used with the other.

  20. Generalized model for Memristor-based Wien family oscillators

    KAUST Repository

    Talukdar, Abdul Hafiz Ibne

    2012-07-23

    In this paper, we report the unconventional characteristics of Memristor in Wien oscillators. Generalized mathematical models are developed to analyze four members of the Wien family using Memristors. Sustained oscillation is reported for all types though oscillating resistance and time dependent poles are present. We have also proposed an analytical model to estimate the desired amplitude of oscillation before the oscillation starts. These Memristor-based oscillation results, presented for the first time, are in good agreement with simulation results. © 2011 Elsevier Ltd.

  1. A generalization of the bond fluctuation model to viscoelastic environments

    International Nuclear Information System (INIS)

    Fritsch, Christian C

    2014-01-01

    A lattice-based simulation method for polymer diffusion in a viscoelastic medium is presented. This method combines the eight-site bond fluctuation model with an algorithm for the simulation of fractional Brownian motion on the lattice. The method applies to unentangled self-avoiding chains and is probed for anomalous diffusion exponents α between 0.7 and 1.0. The simulation results are in very good agreement with the predictions of the generalized Rouse model of a self-avoiding chain polymer in a viscoelastic medium. (paper)

  2. Structural dynamic analysis with generalized damping models analysis

    CERN Document Server

    Adhikari , Sondipon

    2013-01-01

    Since Lord Rayleigh introduced the idea of viscous damping in his classic work ""The Theory of Sound"" in 1877, it has become standard practice to use this approach in dynamics, covering a wide range of applications from aerospace to civil engineering. However, in the majority of practical cases this approach is adopted more for mathematical convenience than for modeling the physics of vibration damping. Over the past decade, extensive research has been undertaken on more general ""non-viscous"" damping models and vibration of non-viscously damped systems. This book, along with a related book

  3. Energy spectra of odd nuclei in the generalized model

    Directory of Open Access Journals (Sweden)

    I. O. Korzh

    2015-04-01

    Full Text Available Based on the generalized nuclear model, energy spectra of the odd nuclei of such elements as 25Mg, 41K, and 65Cu are determined, and the structure of wave functions of these nuclei in the excited and normal states is studied. High quality in determining the energy spectra is possible due to the accurate calculations of all elements of the energy matrix. It is demonstrated that the structure of the wave functions so determined provides the possibility to more accurately select the nuclear model and the method for calculating the nucleon cross-sections of the inelastic scattering of nucleons by odd nuclei.

  4. Regularization Paths for Generalized Linear Models via Coordinate Descent

    Directory of Open Access Journals (Sweden)

    Jerome Friedman

    2010-02-01

    Full Text Available We develop fast algorithms for estimation of generalized linear models with convex penalties. The models include linear regression, two-class logistic regression, and multi- nomial regression problems while the penalties include ℓ1 (the lasso, ℓ2 (ridge regression and mixtures of the two (the elastic net. The algorithms use cyclical coordinate descent, computed along a regularization path. The methods can handle large problems and can also deal efficiently with sparse features. In comparative timings we find that the new algorithms are considerably faster than competing methods.

  5. Pairing correlations in a generalized Hubbard model for the cuprates

    Science.gov (United States)

    Arrachea, Liliana; Aligia, A. A.

    2000-04-01

    Using numerical diagonalization of a 4×4 cluster, we calculate on-site s, extended-s, and dx2-y2 pairing correlation functions (PCF's) in an effective generalized Hubbard model for the cuprates, with nearest-neighbor correlated hopping and next-nearest-neighbor hopping t'. The vertex contributions to the PCF's are significantly enhanced, relative to the t-t'-U model. The behavior of the PCF's and their vertex contributions, and signatures of anomalous flux quantization, indicate superconductivity in the d-wave channel for moderate doping and in the s-wave channel for high doping and small U.

  6. dx2-y2 superconductivity in a generalized Hubbard model

    Science.gov (United States)

    Arrachea, Liliana; Aligia, A. A.

    1999-01-01

    We consider an extended Hubbard model with nearest-neighbor correlated hopping and next-nearest-neighbor hopping t' obtained as an effective model for cuprate superconductors. Using a generalized Hartree-Fock BCS approximation, we find that for high enough t' and doping, antiferromagnetism is destroyed and the system exhibits d-wave superconductivity. Near optimal doping we consider the effect of antiferromagnetic spin fluctuations on the normal self-energy using a phenomenological susceptibility. The resulting superconducting critical temperature as a function of doping is in good agreement with experiment.

  7. Pairing Correlations in a Generalized Hubbard Model for the Cuprates

    OpenAIRE

    Arrachea, L.; Aligia, A.

    1999-01-01

    Using numerical diagonalization of a 4x4 cluster, we calculate on-site s, extended s and d pairing correlation functions (PCF) in an effective generalized Hubbard model for the cuprates, with nearest-neighbor correlated hopping and next nearest-neighbor hopping t'. The vertex contributions (VC) to the PCF are significantly enhanced, relative to the t-t'-U model. The behavior of the PCF and their VC, and signatures of anomalous flux quantization, indicate superconductivity in the d-wave channe...

  8. The linear model and hypothesis a general unifying theory

    CERN Document Server

    Seber, George

    2015-01-01

    This book provides a concise and integrated overview of hypothesis testing in four important subject areas, namely linear and nonlinear models, multivariate analysis, and large sample theory. The approach used is a geometrical one based on the concept of projections and their associated idempotent matrices, thus largely avoiding the need to involve matrix ranks. It is shown that all the hypotheses encountered are either linear or asymptotically linear, and that all the underlying models used are either exactly or asymptotically linear normal models. This equivalence can be used, for example, to extend the concept of orthogonality in the analysis of variance to other models, and to show that the asymptotic equivalence of the likelihood ratio, Wald, and Score (Lagrange Multiplier) hypothesis tests generally applies.

  9. Video-assistiertes Feedback im Praktischen Jahr der Allgemeinmedizin – am Beispiel hausärztlicher Leitlinien [Video-assisted feedback in general practice internships using German general practitioner's guidelines

    Directory of Open Access Journals (Sweden)

    Bölter, Regine

    2012-11-01

    Full Text Available [english] Introduction: The planned modification of the Medical Licenses Act in Germany will strengthen the specialty of general practice. Therefore, medical students should get to know the daily routine of general practitioners during their academic studies. At least 10% of students should get the possibility to spend one quarter of the internship, in the last year of their academic studies, in a practice of family medicine. The demonstrated teaching method aims at giving feedback to the student based on video recordings of patient consultations (student-patient with the help of a checklist. Video-feedback is already successful used in medical teaching in Germany and abroad. This feasibility study aims at assessing the practicability of video-assisted feedback as a teaching method during internship in general practice. Teaching method: First of all, the general practice chooses a guideline as the learning objective. Secondly, a subsequent patient – student – consultation is recorded on video. Afterwards, a video-assisted formative feedback is given by the physician. A checklist with learning objectives (communication, medical examination, a structured case report according to the guideline is used to structure the feedback content. Feasibility: The feasibility was assessed by a semi structured interview in order to gain insight into barriers and challenges for future implementation. The teaching method was performed in one general practice. Afterwards the teaching physician and the trainee intern were interviewed. The following four main categories were identified: feasibility, performance, implementation in daily routine, challenges of the teaching concept.The results of the feasibility study show general practicability of this approach. Installing a video camera in one examination room may solve technical problems. The trainee intern mentioned theoretical and practical benefits using the guideline. The teaching physician noted the

  10. Contextual interactions in a generalized energy model of complex cells.

    Science.gov (United States)

    Dellen, Babette K; Clark, John W; Wessel, Ralf

    2009-01-01

    We propose a generalized energy model of complex cells to describe modulatory contextual influences on the responses of neurons in the primary visual cortex (V1). Many orientation-selective cells in V1 respond to contrast of orientation and motion of stimuli exciting the classical receptive field (CRF) and the non-CRF, or surround. In the proposed model, a central spatiotemporal filter, defining the CRF, is nonlinearly combined with a spatiotemporal filter extending into the non-CRF. These filters are assumed to describe simple-cell responses, while the nonlinear combination of their responses describes the responses of complex cells. This mathematical operation accounts for the inherent nonlinearity of complex cells, such as phase independence and frequency doubling, and for nonlinear interactions between stimuli in the CRF and surround of the cell, including sensitivity to feature contrast. If only the CRF of the generalized complex cell is stimulated by a drifting grating, the model reduces to the standard energy model. The theoretical predictions of the model are supported by computer simulations and compared with experimental data from V1.

  11. Guidelines for seizure management in palliative care: Proposal for an updated clinical practice model based on a systematic literature review.

    Science.gov (United States)

    León Ruiz, M; Rodríguez Sarasa, M L; Sanjuán Rodríguez, L; Pérez Nieves, M T; Ibáñez Estéllez, F; Arce Arce, S; García-Albea Ristol, E; Benito-León, J

    2017-02-27

    Very little has been written on seizure management in palliative care (PC). Given this situation, and considering the forthcoming setting up of the Palliative Care Unit at our neurorehabilitation centre, the Clínica San Vicente, we decided to establish a series of guidelines on the use of antiepileptic drugs (AEDs) for handling seizures in PC. We conducted a literature search in PubMed to identify articles, recent manuals, and clinical practice guidelines on seizure management in PC published by the most relevant scientific societies. Clinical practice guidelines are essential to identify patients eligible for PC, manage seizures adequately, and avoid unnecessary distress to these patients and their families. Given the profile of these patients, we recommend choosing AEDs with a low interaction potential and which can be administered by the parenteral route, preferably intravenously. Diazepam and midazolam appear to be the most suitable AEDs during the acute phase whereas levetiracetam, valproic acid, and lacosamide are recommended for refractory cases and long-term treatment. These guidelines provide general recommendations that must be adapted to each particular clinical case. Nevertheless, we will require further well-designed randomised controlled clinical trials including large samples of patients eligible for PC to draft a consensus document recommending adequate, rational, and effective use of AEDs, based on a high level of evidence, in this highly complex area of medical care. Copyright © 2017 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Border Collision Bifurcations in a Generalized Model of Population Dynamics

    Directory of Open Access Journals (Sweden)

    Lilia M. Ladino

    2016-01-01

    Full Text Available We analyze the dynamics of a generalized discrete time population model of a two-stage species with recruitment and capture. This generalization, which is inspired by other approaches and real data that one can find in literature, consists in considering no restriction for the value of the two key parameters appearing in the model, that is, the natural death rate and the mortality rate due to fishing activity. In the more general case the feasibility of the system has been preserved by posing opportune formulas for the piecewise map defining the model. The resulting two-dimensional nonlinear map is not smooth, though continuous, as its definition changes as any border is crossed in the phase plane. Hence, techniques from the mathematical theory of piecewise smooth dynamical systems must be applied to show that, due to the existence of borders, abrupt changes in the dynamic behavior of population sizes and multistability emerge. The main novelty of the present contribution with respect to the previous ones is that, while using real data, richer dynamics are produced, such as fluctuations and multistability. Such new evidences are of great interest in biology since new strategies to preserve the survival of the species can be suggested.

  13. A general mixture model for sediment laden flows

    Science.gov (United States)

    Liang, Lixin; Yu, Xiping; Bombardelli, Fabián

    2017-09-01

    A mixture model for general description of sediment-laden flows is developed based on an Eulerian-Eulerian two-phase flow theory, with the aim at gaining computational speed in the prediction, but preserving the accuracy of the complete two-fluid model. The basic equations of the model include the mass and momentum conservation equations for the sediment-water mixture, and the mass conservation equation for sediment. However, a newly-obtained expression for the slip velocity between phases allows for the computation of the sediment motion, without the need of solving the momentum equation for sediment. The turbulent motion is represented for both the fluid and the particulate phases. A modified k-ε model is used to describe the fluid turbulence while an algebraic model is adopted for turbulent motion of particles. A two-dimensional finite difference method based on the SMAC scheme was used to numerically solve the mathematical model. The model is validated through simulations of fluid and suspended sediment motion in steady open-channel flows, both in equilibrium and non-equilibrium states, as well as in oscillatory flows. The computed sediment concentrations, horizontal velocity and turbulent kinetic energy of the mixture are all shown to be in good agreement with available experimental data, and importantly, this is done at a fraction of the computational efforts required by the complete two-fluid model.

  14. A general modeling framework for describing spatially structured population dynamics

    Science.gov (United States)

    Sample, Christine; Fryxell, John; Bieri, Joanna; Federico, Paula; Earl, Julia; Wiederholt, Ruscena; Mattsson, Brady; Flockhart, Tyler; Nicol, Sam; Diffendorfer, James E.; Thogmartin, Wayne E.; Erickson, Richard A.; Norris, D. Ryan

    2017-01-01

    Variation in movement across time and space fundamentally shapes the abundance and distribution of populations. Although a variety of approaches model structured population dynamics, they are limited to specific types of spatially structured populations and lack a unifying framework. Here, we propose a unified network-based framework sufficiently novel in its flexibility to capture a wide variety of spatiotemporal processes including metapopulations and a range of migratory patterns. It can accommodate different kinds of age structures, forms of population growth, dispersal, nomadism and migration, and alternative life-history strategies. Our objective was to link three general elements common to all spatially structured populations (space, time and movement) under a single mathematical framework. To do this, we adopt a network modeling approach. The spatial structure of a population is represented by a weighted and directed network. Each node and each edge has a set of attributes which vary through time. The dynamics of our network-based population is modeled with discrete time steps. Using both theoretical and real-world examples, we show how common elements recur across species with disparate movement strategies and how they can be combined under a unified mathematical framework. We illustrate how metapopulations, various migratory patterns, and nomadism can be represented with this modeling approach. We also apply our network-based framework to four organisms spanning a wide range of life histories, movement patterns, and carrying capacities. General computer code to implement our framework is provided, which can be applied to almost any spatially structured population. This framework contributes to our theoretical understanding of population dynamics and has practical management applications, including understanding the impact of perturbations on population size, distribution, and movement patterns. By working within a common framework, there is less chance

  15. A general modeling framework for describing spatially structured population dynamics.

    Science.gov (United States)

    Sample, Christine; Fryxell, John M; Bieri, Joanna A; Federico, Paula; Earl, Julia E; Wiederholt, Ruscena; Mattsson, Brady J; Flockhart, D T Tyler; Nicol, Sam; Diffendorfer, Jay E; Thogmartin, Wayne E; Erickson, Richard A; Norris, D Ryan

    2018-01-01

    Variation in movement across time and space fundamentally shapes the abundance and distribution of populations. Although a variety of approaches model structured population dynamics, they are limited to specific types of spatially structured populations and lack a unifying framework. Here, we propose a unified network-based framework sufficiently novel in its flexibility to capture a wide variety of spatiotemporal processes including metapopulations and a range of migratory patterns. It can accommodate different kinds of age structures, forms of population growth, dispersal, nomadism and migration, and alternative life-history strategies. Our objective was to link three general elements common to all spatially structured populations (space, time and movement) under a single mathematical framework. To do this, we adopt a network modeling approach. The spatial structure of a population is represented by a weighted and directed network. Each node and each edge has a set of attributes which vary through time. The dynamics of our network-based population is modeled with discrete time steps. Using both theoretical and real-world examples, we show how common elements recur across species with disparate movement strategies and how they can be combined under a unified mathematical framework. We illustrate how metapopulations, various migratory patterns, and nomadism can be represented with this modeling approach. We also apply our network-based framework to four organisms spanning a wide range of life histories, movement patterns, and carrying capacities. General computer code to implement our framework is provided, which can be applied to almost any spatially structured population. This framework contributes to our theoretical understanding of population dynamics and has practical management applications, including understanding the impact of perturbations on population size, distribution, and movement patterns. By working within a common framework, there is less chance

  16. The new hypertension guidelines.

    Science.gov (United States)

    Stern, Ralph H

    2013-10-01

    The Canadian Hypertension Education Program (CHEP) has published guidelines annually since 2000. The CHEP guidelines are a model of concise, comprehensive, up-to-date, evidence-rated guidelines for physicians who diagnose and treat hypertension. The guidelines address measurement of blood pressure and the definition of hypertension, secondary hypertension evaluation and treatment, and blood pressure targets and medication choices in patients with and without compelling indications. This review describes CHEP's process for developing guidelines and provides an overview of the 2013 recommendations. ©2013 Wiley Periodicals, Inc.

  17. General

    Indian Academy of Sciences (India)

    Page S20: NMR compound 4i. Page S22: NMR compound 4j. General: Chemicals were purchased from Fluka, Merck and Aldrich Chemical Companies. All the products were characterized by comparison of their IR, 1H NMR and 13C NMR spectroscopic data and their melting points with reported values. General procedure ...

  18. Reshocks, rarefactions, and the generalized Layzer model for hydrodynamic instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Mikaelian, K O

    2008-06-10

    We report numerical simulations and analytic modeling of shock tube experiments on Rayleigh-Taylor and Richtmyer-Meshkov instabilities. We examine single interfaces of the type A/B where the incident shock is initiated in A and the transmitted shock proceeds into B. Examples are He/air and air/He. In addition, we study finite-thickness or double-interface A/B/A configurations like air/SF{sub 6}/air gas-curtain experiments. We first consider conventional shock tubes that have a 'fixed' boundary: A solid endwall which reflects the transmitted shock and reshocks the interface(s). Then we focus on new experiments with a 'free' boundary--a membrane disrupted mechanically or by the transmitted shock, sending back a rarefaction towards the interface(s). Complex acceleration histories are achieved, relevant for Inertial Confinement Fusion implosions. We compare our simulation results with a generalized Layzer model for two fluids with time-dependent densities, and derive a new freeze-out condition whereby accelerating and compressive forces cancel each other out. Except for the recently reported failures of the Layzer model, the generalized Layzer model and hydrocode simulations for reshocks and rarefactions agree well with each other, and remain to be verified experimentally.

  19. Generalized linear mixed model for segregation distortion analysis.

    Science.gov (United States)

    Zhan, Haimao; Xu, Shizhong

    2011-11-11

    Segregation distortion is a phenomenon that the observed genotypic frequencies of a locus fall outside the expected Mendelian segregation ratio. The main cause of segregation distortion is viability selection on linked marker loci. These viability selection loci can be mapped using genome-wide marker information. We developed a generalized linear mixed model (GLMM) under the liability model to jointly map all viability selection loci of the genome. Using a hierarchical generalized linear mixed model, we can handle the number of loci several times larger than the sample size. We used a dataset from an F(2) mouse family derived from the cross of two inbred lines to test the model and detected a major segregation distortion locus contributing 75% of the variance of the underlying liability. Replicated simulation experiments confirm that the power of viability locus detection is high and the false positive rate is low. Not only can the method be used to detect segregation distortion loci, but also used for mapping quantitative trait loci of disease traits using case only data in humans and selected populations in plants and animals.

  20. A generalized and parameterized interference model for cognitive radio networks

    KAUST Repository

    Mahmood, Nurul Huda

    2011-06-01

    For meaningful co-existence of cognitive radios with primary system, it is imperative that the cognitive radio system is aware of how much interference it generates at the primary receivers. This can be done through statistical modeling of the interference as perceived at the primary receivers. In this work, we propose a generalized model for the interference generated by a cognitive radio network, in the presence of small and large scale fading, at a primary receiver located at the origin. We then demonstrate how this model can be used to estimate the impact of cognitive radio transmission on the primary receiver in terms of different outage probabilities. Finally, our analytical findings are validated through some selected computer-based simulations. © 2011 IEEE.

  1. Three General Theoretical Models in Sociology: An Articulated ?(Disunity?

    Directory of Open Access Journals (Sweden)

    Thaís García-Pereiro

    2015-01-01

    Full Text Available After merely a brief, comparative reconstruction of the three most general theoretical models underlying contemporary Sociology (atomic, systemic, and fluid it becomes necessary to review the question about the unity or plurality of Sociology, which is the main objective of this paper. To do so, the basic terms of the question are firstly updated by following the hegemonic trends in current studies of science. Secondly the convergences and divergences among the three models discussed are shown. Following some additional discussion, the conclusion is reached that contemporary Sociology is not unitary, and need not be so. It is plural, but its plurality is limited and articulated by those very models. It may therefore be portrayed as integrated and commensurable, to the extent that a partial and unstable (disunity may be said to exist in Sociology, which is not too far off from what happens in the natural sciences.

  2. Analysis of Robust Quasi-deviances for Generalized Linear Models

    Directory of Open Access Journals (Sweden)

    Eva Cantoni

    2004-04-01

    Full Text Available Generalized linear models (McCullagh and Nelder 1989 are a popular technique for modeling a large variety of continuous and discrete data. They assume that the response variables Yi , for i = 1, . . . , n, come from a distribution belonging to the exponential family, such that E[Yi ] = ?i and V[Yi ] = V (?i , and that ?i = g(?i = xiT?, where ? ? IR p is the vector of parameters, xi ? IR p, and g(. is the link function. The non-robustness of the maximum likelihood and the maximum quasi-likelihood estimators has been studied extensively in the literature. For model selection, the classical analysis-of-deviance approach shares the same bad robustness properties. To cope with this, Cantoni and Ronchetti (2001 propose a robust approach based on robust quasi-deviance functions for estimation and variable selection. We refer to that paper for a deeper discussion and the review of the literature.

  3. Generalized Information Matrix Tests for Detecting Model Misspecification

    Directory of Open Access Journals (Sweden)

    Richard M. Golden

    2016-11-01

    Full Text Available Generalized Information Matrix Tests (GIMTs have recently been used for detecting the presence of misspecification in regression models in both randomized controlled trials and observational studies. In this paper, a unified GIMT framework is developed for the purpose of identifying, classifying, and deriving novel model misspecification tests for finite-dimensional smooth probability models. These GIMTs include previously published as well as newly developed information matrix tests. To illustrate the application of the GIMT framework, we derived and assessed the performance of new GIMTs for binary logistic regression. Although all GIMTs exhibited good level and power performance for the larger sample sizes, GIMT statistics with fewer degrees of freedom and derived using log-likelihood third derivatives exhibited improved level and power performance.

  4. Generalized transport model for phase transition with memory

    International Nuclear Information System (INIS)

    Chen, Chi; Ciucci, Francesco

    2013-01-01

    A general model for phenomenological transport in phase transition is derived, which extends Jäckle and Frisch model of phase transition with memory and the Cahn–Hilliard model. In addition to including interfacial energy to account for the presence of interfaces, we introduce viscosity and relaxation contributions, which result from incorporating memory effect into the driving potential. Our simulation results show that even without interfacial energy term, the viscous term can lead to transient diffuse interfaces. From the phase transition induced hysteresis, we discover different energy dissipation mechanism for the interfacial energy and the viscosity effect. In addition, by combining viscosity and interfacial energy, we find that if the former dominates, then the concentration difference across the phase boundary is reduced; conversely, if the interfacial energy is greater then this difference is enlarged.

  5. Topics in conformal invariance and generalized sigma models

    International Nuclear Information System (INIS)

    Bernardo, L.M.; Lawrence Berkeley National Lab., CA

    1997-05-01

    This thesis consists of two different parts, having in common the fact that in both, conformal invariance plays a central role. In the first part, the author derives conditions for conformal invariance, in the large N limit, and for the existence of an infinite number of commuting classical conserved quantities, in the Generalized Thirring Model. The treatment uses the bosonized version of the model. Two different approaches are used to derive conditions for conformal invariance: the background field method and the Hamiltonian method based on an operator algebra, and the agreement between them is established. The author constructs two infinite sets of non-local conserved charges, by specifying either periodic or open boundary conditions, and he finds the Poisson Bracket algebra satisfied by them. A free field representation of the algebra satisfied by the relevant dynamical variables of the model is also presented, and the structure of the stress tensor in terms of free fields (and free currents) is studied in detail. In the second part, the author proposes a new approach for deriving the string field equations from a general sigma model on the world sheet. This approach leads to an equation which combines some of the attractive features of both the renormalization group method and the covariant beta function treatment of the massless excitations. It has the advantage of being covariant under a very general set of both local and non-local transformations in the field space. The author applies it to the tachyon, massless and first massive level, and shows that the resulting field equations reproduce the correct spectrum of a left-right symmetric closed bosonic string

  6. A generalized formulation of the dynamic Smagorinsky model

    Directory of Open Access Journals (Sweden)

    Urs Schaefer-Rolffs

    2017-04-01

    Full Text Available A generalized formulation of the Dynamic Smagorinsky Model (DSM is proposed as a versatile turbulent momentum diffusion scheme for Large-Eddy Simulations. The difference to previous versions of the DSM is a modified test filter range that can be chosen independently from the resolution scale to separate the impact of the test filter on the simulated flow from the impact of the resolution. The generalized DSM (gDSM in a two-dimensional version is validated in a verification study as a horizontal momentum diffusion scheme with the Kühlungsborn Mechanistic General Circulation Model at high resolution (wavenumber 330 without hyperdiffusion. Three-day averaged results applying three different test filters in the macro-turbulent inertial range are presented and compared with analogous simulations where the standard DSM is used instead. The comparison of the different filters results in all cases in similar globally averaged Smagorinsky parameters cS≃0.35$c_S\\simeq0.35$ and horizontal kinetic energy spectra. Hence, the basic assumption of scale invariance underlying the application of the gDSM to parameterize atmospheric turbulence is justified. In addition, the smallest resolved scales contain less energy when the gDSM is applied, thus increasing the stability of the simulation.

  7. Applications of Skew Models Using Generalized Logistic Distribution

    Directory of Open Access Journals (Sweden)

    Pushpa Narayan Rathie

    2016-04-01

    Full Text Available We use the skew distribution generation procedure proposed by Azzalini [Scand. J. Stat., 1985, 12, 171–178] to create three new probability distribution functions. These models make use of normal, student-t and generalized logistic distribution, see Rathie and Swamee [Technical Research Report No. 07/2006. Department of Statistics, University of Brasilia: Brasilia, Brazil, 2006]. Expressions for the moments about origin are derived. Graphical illustrations are also provided. The distributions derived in this paper can be seen as generalizations of the distributions given by Nadarajah and Kotz [Acta Appl. Math., 2006, 91, 1–37]. Applications with unimodal and bimodal data are given to illustrate the applicability of the results derived in this paper. The applications include the analysis of the following data sets: (a spending on public education in various countries in 2003; (b total expenditure on health in 2009 in various countries and (c waiting time between eruptions of the Old Faithful Geyser in the Yellow Stone National Park, Wyoming, USA. We compare the fit of the distributions introduced in this paper with the distributions given by Nadarajah and Kotz [Acta Appl. Math., 2006, 91, 1–37]. The results show that our distributions, in general, fit better the data sets. The general R codes for fitting the distributions introduced in this paper are given in Appendix A.

  8. Guideline compliance in chronic heart failure patients with multiple comorbid diseases: evaluation of an individualised multidisciplinary model of care.

    Directory of Open Access Journals (Sweden)

    Tam H Ho

    Full Text Available OBJECTIVE: To assess the impact of individualised, reconciled evidence-based recommendations (IRERs and multidisciplinary care in patients with chronic heart failure (CHF on clinical guideline compliance for CHF and common comorbid conditions. DESIGN AND SETTING: A retrospective hospital clinical audit conducted between 1st July 2006 and February 2011. PARTICIPANTS: A total of 255 patients with a diagnosis of CHF who attended the Multidisciplinary Ambulatory Consulting Services (MACS clinics, at the Royal Adelaide Hospital, were included. MAIN OUTCOME MEASURES: Compliance with Australian clinical guideline recommendations for CHF, atrial fibrillation, diabetes mellitus and ischaemic heart disease. RESULTS: Study participants had a median of eight medical conditions (IQR 6-10 and were on an average of 10 (±4 unique medications. Compliance with clinical guideline recommendations for pharmacological therapy for CHF, comorbid atrial fibrillation, diabetes or ischaemic heart disease was high, ranging from 86% for lipid lowering therapy to 98% anti-platelet agents. For all conditions, compliance with lifestyle recommendations was lower than pharmacological therapy, ranging from no podiatry reviews for CHF patients with comorbid diabetes to 75% for heart failure education. Concordance with many guideline recommendations was significantly associated if the patient had IRERs determined, a greater number of recommendations, more clinic visits or if patients participated in a heart failure program. CONCLUSIONS: Despite the high number of comorbid conditions and resulting complexity of the management, high compliance to clinical guideline recommendations was associated with IRER determination in older patients with CHF. Importantly these recommendations need to be communicated to the patient's general practitioner, regularly monitored and adjusted at clinic visits.

  9. A generalized logarithmic image processing model based on the gigavision sensor model.

    Science.gov (United States)

    Deng, Guang

    2012-03-01

    The logarithmic image processing (LIP) model is a mathematical theory providing generalized linear operations for image processing. The gigavision sensor (GVS) is a new imaging device that can be described by a statistical model. In this paper, by studying these two seemingly unrelated models, we develop a generalized LIP (GLIP) model. With the LIP model being its special case, the GLIP model not only provides new insights into the LIP model but also defines new image representations and operations for solving general image processing problems that are not necessarily related to the GVS. A new parametric LIP model is also developed. To illustrate the application of the new scalar multiplication operation, we propose an energy-preserving algorithm for tone mapping, which is a necessary step in image dehazing. By comparing with results using two state-of-the-art algorithms, we show that the new scalar multiplication operation is an effective tool for tone mapping.

  10. Generalized Magnetic Field Effects in Burgers' Nanofluid Model.

    Directory of Open Access Journals (Sweden)

    M M Rashidi

    Full Text Available Analysis has been conducted to present the generalized magnetic field effects on the flow of a Burgers' nanofluid over an inclined wall. Mathematical modelling for hydro-magnetics reveals that the term "[Formula: see text]" is for the Newtonian model whereas the generalized magnetic field term (as mentioned in Eq 4 is for the Burgers' model which is incorporated in the current analysis to get the real insight of the problem for hydro-magnetics. Brownian motion and thermophoresis phenomenon are presented to analyze the nanofluidics for the non-Newtonian fluid. Mathematical analysis is completed in the presence of non-uniform heat generation/absorption. The constructed set of partial differential system is converted into coupled nonlinear ordinary differential system by employing the suitable transformations. Homotopy approach is employed to construct the analytical solutions which are shown graphically for sundr5y parameters including Deborah numbers, magnetic field, thermophoresis, Brownian motion and non-uniform heat generation/absorption. A comparative study is also presented showing the comparison of present results with an already published data.

  11. Generalized martingale model of the uncertainty evolution of streamflow forecasts

    Science.gov (United States)

    Zhao, Tongtiegang; Zhao, Jianshi; Yang, Dawen; Wang, Hao

    2013-07-01

    Streamflow forecasts are dynamically updated in real-time, thus facilitating a process of forecast uncertainty evolution. Forecast uncertainty generally decreases over time and as more hydrologic information becomes available. The process of forecasting and uncertainty updating can be described by the martingale model of forecast evolution (MMFE), which formulates the total forecast uncertainty of a streamflow in one future period as the sum of forecast improvements in the intermediate periods. This study tests the assumptions, i.e., unbiasedness, Gaussianity, temporal independence, and stationarity, of MMFE using real-world streamflow forecast data. The results show that (1) real-world forecasts can be biased and tend to underestimate the actual streamflow, and (2) real-world forecast uncertainty is non-Gaussian and heavy-tailed. Based on these statistical tests, this study proposes a generalized martingale model GMMFE for the simulation of biased and non-Gaussian forecast uncertainties. The new model combines the normal quantile transform (NQT) with MMFE to formulate the uncertainty evolution of real-world streamflow forecasts. Reservoir operations based on a synthetic forecast by GMMFE illustrates that applications of streamflow forecasting facilitate utility improvements and that special attention should be focused on the statistical distribution of forecast uncertainty.

  12. Introducing Charge Hydration Asymmetry into the Generalized Born Model.

    Science.gov (United States)

    Mukhopadhyay, Abhishek; Aguilar, Boris H; Tolokh, Igor S; Onufriev, Alexey V

    2014-04-08

    The effect of charge hydration asymmetry (CHA)-non-invariance of solvation free energy upon solute charge inversion-is missing from the standard linear response continuum electrostatics. The proposed charge hydration asymmetric-generalized Born (CHA-GB) approximation introduces this effect into the popular generalized Born (GB) model. The CHA is added to the GB equation via an analytical correction that quantifies the specific propensity of CHA of a given water model; the latter is determined by the charge distribution within the water model. Significant variations in CHA seen in explicit water (TIP3P, TIP4P-Ew, and TIP5P-E) free energy calculations on charge-inverted "molecular bracelets" are closely reproduced by CHA-GB, with the accuracy similar to models such as SEA and 3D-RISM that go beyond the linear response. Compared against reference explicit (TIP3P) electrostatic solvation free energies, CHA-GB shows about a 40% improvement in accuracy over the canonical GB, tested on a diverse set of 248 rigid small neutral molecules (root mean square error, rmse = 0.88 kcal/mol for CHA-GB vs 1.24 kcal/mol for GB) and 48 conformations of amino acid analogs (rmse = 0.81 kcal/mol vs 1.26 kcal/mol). CHA-GB employs a novel definition of the dielectric boundary that does not subsume the CHA effects into the intrinsic atomic radii. The strategy leads to finding a new set of intrinsic atomic radii optimized for CHA-GB; these radii show physically meaningful variation with the atom type, in contrast to the radii set optimized for GB. Compared to several popular radii sets used with the original GB model, the new radii set shows better transferability between different classes of molecules.

  13. A general relativistic hydrostatic model for a galaxy

    International Nuclear Information System (INIS)

    Hojman, R.; Pena, L.; Zamorano, N.

    1991-08-01

    The existence of huge amounts of mass laying at the center of some galaxies has been inferred by data gathered at different wavelengths. It seems reasonable then, to incorporate general relativity in the study of these objects. A general relativistic hydrostatic model for a galaxy is studied. We assume that the galaxy is dominated by the dark mass except at the nucleus, where the luminous matter prevails. It considers four different concentric spherically symmetric regions, properly matched and with a specific equation of state for each of them. It yields a slowly raising orbital velocity for a test particle moving in the background gravitational field of the dark matter region. In this sense we think of this model as representing a spiral galaxy. The dependence of the mass on the radius in cluster and field spiral galaxies published recently, can be used to fix the size of the inner luminous core. A vanishing pressure at the edge of the galaxy and the assumption of hydrostatic equilibrium everywhere generates a jump in the density and the orbital velocity at the shell enclosing the galaxy. This is a prediction of this model. The ratio between the size core and the shells introduced here are proportional to their densities. In this sense the model is scale invariant. It can be used to reproduce a galaxy or the central region of a galaxy. We have also compared our results with those obtained with the Newtonian isothermal sphere. The luminosity is not included in our model as an extra variable in the determination of the orbital velocity. (author). 29 refs, 10 figs

  14. A generalized methodology to characterize composite materials for pyrolysis models

    Science.gov (United States)

    McKinnon, Mark B.

    The predictive capabilities of computational fire models have improved in recent years such that models have become an integral part of many research efforts. Models improve the understanding of the fire risk of materials and may decrease the number of expensive experiments required to assess the fire hazard of a specific material or designed space. A critical component of a predictive fire model is the pyrolysis sub-model that provides a mathematical representation of the rate of gaseous fuel production from condensed phase fuels given a heat flux incident to the material surface. The modern, comprehensive pyrolysis sub-models that are common today require the definition of many model parameters to accurately represent the physical description of materials that are ubiquitous in the built environment. Coupled with the increase in the number of parameters required to accurately represent the pyrolysis of materials is the increasing prevalence in the built environment of engineered composite materials that have never been measured or modeled. The motivation behind this project is to develop a systematic, generalized methodology to determine the requisite parameters to generate pyrolysis models with predictive capabilities for layered composite materials that are common in industrial and commercial applications. This methodology has been applied to four common composites in this work that exhibit a range of material structures and component materials. The methodology utilizes a multi-scale experimental approach in which each test is designed to isolate and determine a specific subset of the parameters required to define a material in the model. Data collected in simultaneous thermogravimetry and differential scanning calorimetry experiments were analyzed to determine the reaction kinetics, thermodynamic properties, and energetics of decomposition for each component of the composite. Data collected in microscale combustion calorimetry experiments were analyzed to

  15. A GENERALIZATION OF TRADITIONAL KANO MODEL FOR CUSTOMER REQUIREMENTS ANALYSIS

    Directory of Open Access Journals (Sweden)

    Renáta Turisová

    2015-07-01

    Full Text Available Purpose: The theory of attractiveness determines the relationship between the technically achieved and customer perceived quality of product attributes. The most frequently used approach in the theory of attractiveness is the implementation of Kano‘s model. There exist a lot of generalizations of that model which take into consideration various aspects and approaches focused on understanding the customer preferences and identification of his priorities for a selling  product. The aim of this article is to outline another possible generalization of Kano‘s model.Methodology/Approach: The traditional Kano’s model captures the nonlinear relationship between reached attributes of quality and customer requirements. The individual attributes of quality are divided into three main categories: must-be, one-dimensional, attractive quality and into two side categories: indifferent and reverse quality. The well selling product has to contain the must-be attribute. It should contain as many one-dimensional attributes as possible. If there are also supplementary attractive attributes, it means that attractiveness of the entire product, from the viewpoint of the customer, nonlinearly sharply rises what has a direct positive impact on a decision of potential customer when purchasing the product. In this article, we show that inclusion of individual quality attributes of a product to the mentioned categories depends, among other things, also on costs on life cycle of the product, respectively on a price of the product on the market.Findings: In practice, we are often encountering the inclusion of products into different price categories: lower, middle and upper class. For a certain type of products the category is either directly declared by a producer (especially in automotive industry, or is determined by a customer by means of assessment of available market prices. To each of those groups of a products different customer expectations can be assigned

  16. Generalized Laplacian eigenmaps for modeling and tracking human motions.

    Science.gov (United States)

    Martinez-del-Rincon, Jesus; Lewandowski, Michal; Nebel, Jean-Christophe; Makris, Dimitrios

    2014-09-01

    This paper presents generalized Laplacian eigenmaps, a novel dimensionality reduction approach designed to address stylistic variations in time series. It generates compact and coherent continuous spaces whose geometry is data-driven. This paper also introduces graph-based particle filter, a novel methodology conceived for efficient tracking in low dimensional space derived from a spectral dimensionality reduction method. Its strengths are a propagation scheme, which facilitates the prediction in time and style, and a noise model coherent with the manifold, which prevents divergence, and increases robustness. Experiments show that a combination of both techniques achieves state-of-the-art performance for human pose tracking in underconstrained scenarios.

  17. Estimation and variable selection for generalized additive partial linear models

    KAUST Repository

    Wang, Li

    2011-08-01

    We study generalized additive partial linear models, proposing the use of polynomial spline smoothing for estimation of nonparametric functions, and deriving quasi-likelihood based estimators for the linear parameters. We establish asymptotic normality for the estimators of the parametric components. The procedure avoids solving large systems of equations as in kernel-based procedures and thus results in gains in computational simplicity. We further develop a class of variable selection procedures for the linear parameters by employing a nonconcave penalized quasi-likelihood, which is shown to have an asymptotic oracle property. Monte Carlo simulations and an empirical example are presented for illustration. © Institute of Mathematical Statistics, 2011.

  18. Computable general equilibrium model fiscal year 2013 capability development report

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Brian Keith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rivera, Michael Kelly [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boero, Riccardo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-17

    This report documents progress made on continued developments of the National Infrastructure Simulation and Analysis Center (NISAC) Computable General Equilibrium Model (NCGEM), developed in fiscal year 2012. In fiscal year 2013, NISAC the treatment of the labor market and tests performed with the model to examine the properties of the solutions computed by the model. To examine these, developers conducted a series of 20 simulations for 20 U.S. States. Each of these simulations compared an economic baseline simulation with an alternative simulation that assumed a 20-percent reduction in overall factor productivity in the manufacturing industries of each State. Differences in the simulation results between the baseline and alternative simulations capture the economic impact of the reduction in factor productivity. While not every State is affected in precisely the same way, the reduction in manufacturing industry productivity negatively affects the manufacturing industries in each State to an extent proportional to the reduction in overall factor productivity. Moreover, overall economic activity decreases when manufacturing sector productivity is reduced. Developers ran two additional simulations: (1) a version of the model for the State of Michigan, with manufacturing divided into two sub-industries (automobile and other vehicle manufacturing as one sub-industry and the rest of manufacturing as the other subindustry); and (2) a version of the model for the United States, divided into 30 industries. NISAC conducted these simulations to illustrate the flexibility of industry definitions in NCGEM and to examine the simulation properties of in more detail.

  19. Scaling of Precipitation Extremes Modelled by Generalized Pareto Distribution

    Science.gov (United States)

    Rajulapati, C. R.; Mujumdar, P. P.

    2017-12-01

    Precipitation extremes are often modelled with data from annual maximum series or peaks over threshold series. The Generalized Pareto Distribution (GPD) is commonly used to fit the peaks over threshold series. Scaling of precipitation extremes from larger time scales to smaller time scales when the extremes are modelled with the GPD is burdened with difficulties arising from varying thresholds for different durations. In this study, the scale invariance theory is used to develop a disaggregation model for precipitation extremes exceeding specified thresholds. A scaling relationship is developed for a range of thresholds obtained from a set of quantiles of non-zero precipitation of different durations. The GPD parameters and exceedance rate parameters are modelled by the Bayesian approach and the uncertainty in scaling exponent is quantified. A quantile based modification in the scaling relationship is proposed for obtaining the varying thresholds and exceedance rate parameters for shorter durations. The disaggregation model is applied to precipitation datasets of Berlin City, Germany and Bangalore City, India. From both the applications, it is observed that the uncertainty in the scaling exponent has a considerable effect on uncertainty in scaled parameters and return levels of shorter durations.

  20. NLO electroweak corrections in general scalar singlet models

    Science.gov (United States)

    Costa, Raul; Sampaio, Marco O. P.; Santos, Rui

    2017-07-01

    If no new physics signals are found, in the coming years, at the Large Hadron Collider Run-2, an increase in precision of the Higgs couplings measurements will shift the discussion to the effects of higher order corrections. In Beyond the Standard Model (BSM) theories this may become the only tool to probe new physics. Extensions of the Standard Model (SM) with several scalar singlets may address several of its problems, namely to explain dark matter, the matter-antimatter asymmetry, or to improve the stability of the SM up to the Planck scale. In this work we propose a general framework to calculate one loop-corrections to the propagators and to the scalar field vacuum expectation values of BSM models with an arbitrary number of scalar singlets. We then apply our method to a real and to a complex scalar singlet models. We assess the importance of the one-loop radiative corrections first by computing them for a tree level mixing sum constraint, and then for the main Higgs production process gg → H. We conclude that, for the currently allowed parameter space of these models, the corrections can be at most a few percent. Notably, a non-zero correction can survive when dark matter is present, in the SM-like limit of the Higgs couplings to other SM particles.

  1. Detection of Fraudulent Transactions Through a Generalized Mixed Linear Models

    Directory of Open Access Journals (Sweden)

    Jackelyne Gómez–Restrepo

    2012-12-01

    Full Text Available The detection of bank frauds is a topic which many financial sector companieshave invested time and resources into. However, finding patterns inthe methodologies used to commit fraud in banks is a job that primarily involvesintimate knowledge of customer behavior, with the idea of isolatingthose transactions which do not correspond to what the client usually does.Thus, the solutions proposed in literature tend to focus on identifying outliersor groups, but fail to analyse each client or forecast fraud. This paperevaluates the implementation of a generalized linear model to detect fraud.With this model, unlike conventional methods, we consider the heterogeneityof customers. We not only generate a global model, but also a model for eachcustomer which describes the behavior of each one according to their transactionalhistory and previously detected fraudulent transactions. In particular,a mixed logistic model is used to estimate the probability that a transactionis fraudulent, using information that has been taken by the banking systemsin different moments of time.

  2. GENERALIZATION TECHNIQUE FOR 2D+SCALE DHE DATA MODEL

    Directory of Open Access Journals (Sweden)

    H. Karim

    2016-10-01

    Full Text Available Different users or applications need different scale model especially in computer application such as game visualization and GIS modelling. Some issues has been raised on fulfilling GIS requirement of retaining the details while minimizing the redundancy of the scale datasets. Previous researchers suggested and attempted to add another dimension such as scale or/and time into a 3D model, but the implementation of scale dimension faces some problems due to the limitations and availability of data structures and data models. Nowadays, various data structures and data models have been proposed to support variety of applications and dimensionality but lack research works has been conducted in terms of supporting scale dimension. Generally, the Dual Half Edge (DHE data structure was designed to work with any perfect 3D spatial object such as buildings. In this paper, we attempt to expand the capability of the DHE data structure toward integration with scale dimension. The description of the concept and implementation of generating 3D-scale (2D spatial + scale dimension for the DHE data structure forms the major discussion of this paper. We strongly believed some advantages such as local modification and topological element (navigation, query and semantic information in scale dimension could be used for the future 3D-scale applications.

  3. Generalized constraint neural network regression model subject to linear priors.

    Science.gov (United States)

    Qu, Ya-Jun; Hu, Bao-Gang

    2011-12-01

    This paper is reports an extension of our previous investigations on adding transparency to neural networks. We focus on a class of linear priors (LPs), such as symmetry, ranking list, boundary, monotonicity, etc., which represent either linear-equality or linear-inequality priors. A generalized constraint neural network-LPs (GCNN-LPs) model is studied. Unlike other existing modeling approaches, the GCNN-LP model exhibits its advantages. First, any LP is embedded by an explicitly structural mode, which may add a higher degree of transparency than using a pure algorithm mode. Second, a direct elimination and least squares approach is adopted to study the model, which produces better performances in both accuracy and computational cost over the Lagrange multiplier techniques in experiments. Specific attention is paid to both "hard (strictly satisfied)" and "soft (weakly satisfied)" constraints for regression problems. Numerical investigations are made on synthetic examples as well as on the real-world datasets. Simulation results demonstrate the effectiveness of the proposed modeling approach in comparison with other existing approaches.

  4. Consumption of foods and beverages in elementary schools: Results of the implementation of the general guidelines for foods and beverages sales in elementary schools in Mexico, stages II and III.

    Science.gov (United States)

    López-Olmedo, Nancy; Jiménez-Aguilar, Alejandra; Morales-Ruan, María Del Carmen; Hernández-Ávila, Mauricio; Shamah-Levy, Teresa; Rivera-Dommarco, Juan A

    2018-02-01

    The Mexican government developed the General Guidelines for the dispensing or distribution of foods and beverages at food sales in elementary schools (Guidelines). The objective is to evaluate the consumption of food and beverages during school hours, in two different stages of the implementation of the Guidelines: stages II (2011-2012) and stage III (2012-2013) in 565 elementary school students. We constructed three categories of consumption according to the origin of food: Home, food brought from home; School, food purchased at school and Both, food from home and food purchased at school. The main results showed that there are differences in both stages in energy intake according to the foods' origin; the category of School has the lowest energy and macronutrients consumption, as well as the closer compliance with de Guidelines recommendations in both stages, while the category of Both has a higher consumption and the less compliance with the Guidelines. This may be indicating an improvement in school guidelines and it is also reflecting the need to reinforce orientation for a healthy diet with respect to foods brought from home. It is necessary to continue with periodic evaluations to measure fulfillment with the Guidelines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. [Treatment of cloud radiative effects in general circulation models

    International Nuclear Information System (INIS)

    Wang, W.C.

    1993-01-01

    This is a renewal proposal for an on-going project of the Department of Energy (DOE)/Atmospheric Radiation Measurement (ARM) Program. The objective of the ARM Program is to improve the treatment of radiation-cloud in GCMs so that reliable predictions of the timing and magnitude of greenhouse gas-induced global warming and regional responses can be made. The ARM Program supports two research areas: (I) The modeling and analysis of data related to the parameterization of clouds and radiation in general circulation models (GCMs); and (II) the development of advanced instrumentation for both mapping the three-dimensional structure of the atmosphere and high accuracy/precision radiometric observations. The present project conducts research in area (I) and focuses on GCM treatment of cloud life cycle, optical properties, and vertical overlapping. The project has two tasks: (1) Development and Refinement of GCM Radiation-Cloud Treatment Using ARM Data; and (2) Validation of GCM Radiation-Cloud Treatment

  6. A stratiform cloud parameterization for General Circulation Models

    International Nuclear Information System (INIS)

    Ghan, S.J.; Leung, L.R.; Chuang, C.C.; Penner, J.E.; McCaa, J.

    1994-01-01

    The crude treatment of clouds in General Circulation Models (GCMs) is widely recognized as a major limitation in the application of these models to predictions of global climate change. The purpose of this project is to develop a paxameterization for stratiform clouds in GCMs that expresses stratiform clouds in terms of bulk microphysical properties and their subgrid variability. In this parameterization, precipitating cloud species are distinguished from non-precipitating species, and the liquid phase is distinguished from the ice phase. The size of the non-precipitating cloud particles (which influences both the cloud radiative properties and the conversion of non-precipitating cloud species to precipitating species) is determined by predicting both the mass and number concentrations of each species

  7. Convex Relaxations for a Generalized Chan-Vese Model

    KAUST Repository

    Bae, Egil

    2013-01-01

    We revisit the Chan-Vese model of image segmentation with a focus on the encoding with several integer-valued labeling functions. We relate several representations with varying amount of complexity and demonstrate the connection to recent relaxations for product sets and to dual maxflow-based formulations. For some special cases, it can be shown that it is possible to guarantee binary minimizers. While this is not true in general, we show how to derive a convex approximation of the combinatorial problem for more than 4 phases. We also provide a method to avoid overcounting of boundaries in the original Chan-Vese model without departing from the efficient product-set representation. Finally, we derive an algorithm to solve the associated discretized problem, and demonstrate that it allows to obtain good approximations for the segmentation problem with various number of regions. © 2013 Springer-Verlag.

  8. A Chemical Containment Model for the General Purpose Work Station

    Science.gov (United States)

    Flippen, Alexis A.; Schmidt, Gregory K.

    1994-01-01

    Contamination control is a critical safety requirement imposed on experiments flying on board the Spacelab. The General Purpose Work Station, a Spacelab support facility used for life sciences space flight experiments, is designed to remove volatile compounds from its internal airpath and thereby minimize contamination of the Spacelab. This is accomplished through the use of a large, multi-stage filter known as the Trace Contaminant Control System. Many experiments planned for the Spacelab require the use of toxic, volatile fixatives in order to preserve specimens prior to postflight analysis. The NASA-Ames Research Center SLS-2 payload, in particular, necessitated the use of several toxic, volatile compounds in order to accomplish the many inflight experiment objectives of this mission. A model was developed based on earlier theories and calculations which provides conservative predictions of the resultant concentrations of these compounds given various spill scenarios. This paper describes the development and application of this model.

  9. Generalized flux states of the t-J model

    International Nuclear Information System (INIS)

    Nori, F.; Abrahams, E.; Zimanyi, G.T.

    1990-01-01

    We investigate certain generalized flux phases arising in a mean-field approach to the t-J model. First, we establish that the energy of noninteracting electrons moving in a uniform magnetic field has an absolute minimum as a function of the flux at exactly one flux quantum per particle. Using this result, we show that if the hard-core nature of the hole bosons is taken into account, then the slave-boson mean-field approximation for the t-J Hamiltonian allows for a solution where both the spinons and the holons experience an average flux of one flux quantum per particle. This enables them to achieve the lowest possible energy within the manifold of spatially uniform flux states. In the case of the continuum model, this is possible only for certain fractional fillings and we speculate that the system may react to this frustration effect by phase separation

  10. Explicit estimating equations for semiparametric generalized linear latent variable models

    KAUST Repository

    Ma, Yanyuan

    2010-07-05

    We study generalized linear latent variable models without requiring a distributional assumption of the latent variables. Using a geometric approach, we derive consistent semiparametric estimators. We demonstrate that these models have a property which is similar to that of a sufficient complete statistic, which enables us to simplify the estimating procedure and explicitly to formulate the semiparametric estimating equations. We further show that the explicit estimators have the usual root n consistency and asymptotic normality. We explain the computational implementation of our method and illustrate the numerical performance of the estimators in finite sample situations via extensive simulation studies. The advantage of our estimators over the existing likelihood approach is also shown via numerical comparison. We employ the method to analyse a real data example from economics. © 2010 Royal Statistical Society.

  11. A stratiform cloud parameterization for general circulation models

    International Nuclear Information System (INIS)

    Ghan, S.J.; Leung, L.R.; Chuang, C.C.; Penner, J.E.; McCaa, J.

    1994-01-01

    The crude treatment of clouds in general circulation models (GCMs) is widely recognized as a major limitation in applying these models to predictions of global climate change. The purpose of this project is to develop in GCMs a stratiform cloud parameterization that expresses clouds in terms of bulk microphysical properties and their subgrid variability. Various clouds variables and their interactions are summarized. Precipitating cloud species are distinguished from non-precipitating species, and the liquid phase is distinguished from the ice phase. The size of the non-precipitating cloud particles (which influences both the cloud radiative properties and the conversion of non-precipitating cloud species to precipitating species) is determined by predicting both the mass and number concentrations of each species

  12. A more general interacting model of holographic dark energy

    International Nuclear Information System (INIS)

    Yu Fei; Zhang Jingfei; Lu Jianbo; Wang Wei; Gui Yuanxing

    2010-01-01

    So far, there have been no theories or observational data that deny the presence of interaction between dark energy and dark matter. We extend naturally the holographic dark energy (HDE) model, proposed by Granda and Oliveros, in which the dark energy density includes not only the square of the Hubble scale, but also the time derivative of the Hubble scale to the case with interaction and the analytic forms for the cosmic parameters are obtained under the specific boundary conditions. The various behaviors concerning the cosmic expansion depend on the introduced numerical parameters which are also constrained. The more general interacting model inherits the features of the previous ones of HDE, keeping the consistency of the theory.

  13. Author Guidelines

    Directory of Open Access Journals (Sweden)

    Yunisrina Qismullah Yusuf

    2014-09-01

    Full Text Available Guidelines for Article Submission   SiELE journal accepts articles on research and development in the field of teaching and learning of English, linguistics, educational development, policy and cultural studies in education. To be considered for publication, the article should be presented in the following system: First page: include a title page with the full title of the paper (must not exceed 16 words, the author(s’ name(s, affiliation(s, phone number(s and e-mail address of the corresponding author. A brief bio-data of the author(s (maximum of 100 words is provided in this page. Second page and subsequent page: Submissions should be between 4000-6000 (including abstract, table(s, figure(s and references in A4 size paper with margins as the following: top 3 cm, bottom 3 cm, right 2.5 cm and left 4 cm. The font is Times New Roman, size 12 and single spaced. The article should generally consist of the following sections: introduction, review of literature, method, findings, discussion and conclusion. Headings and subheadings should be presented as follows (provide a space between the headings and sub-headings. 1         INTRODUCTION 1.1      Subheading of the content  1.1.1   Subheading of the content  For Tables, the title size is 12 and the content size is 10. Please number the tables subsequently throughout your article and the title is written above the table. For Figures, the title size is 12 and the content size (if any is 10. Please number the figures subsequently throughout your article and the title is written below the figure. The reference list should be arranged alphabetically following the guidelines of the Publication Manual of the American Psychological Association (5th ed.. See the following examples:   Book: Ellis, R. (2003. Task-based language learning and teaching. Oxford: Oxford University Press. Internet source: Andrewes, S. (2003. Group work v. whole-class activities. Retrieved October 1, 2012 from

  14. Author Guidelines

    Directory of Open Access Journals (Sweden)

    Yunisrina Qismullah Yusuf

    2016-03-01

    Full Text Available Guidelines for Article Submission SiELE journal accepts articles on research and development in the field of teaching and learning of English, linguistics, educational development, policy and cultural studies in education. To be considered for publication, the article should be presented in the following system: First page: include a title page with the full title of the paper (must not exceed 16 words, the author(s’ name(s, affiliation(s, phone number(s and e-mail address of the corresponding author. A brief bio-data of the author(s (maximum of 100 words is provided in this page. Second p age and subsequent page: Submissions should be between 4000-6000 (including abstract, table(s, figure(s and references in A4 size paper with margins as the following: top 3 cm, bottom 3 cm, right 2.5 cm and left 4 cm. The font is Times New Roman, size 12 and single spaced. The article should generally consist of the following sections: introduction, review of literature, method, findings, discussion and conclusion. Headings and subheadings should be presented as follows (provide a space between the headings and sub-headings. 1 INTRODUCTION 1.1 Subheading of the Content 1.1.1 Subheading of the Content For Tables, the title size is 12 and the content size is 10. Please number the tables subsequently throughout your article and the title is written above the table. For Figures, the title size is 12 and the content size (if any is 10. Please number the figures subsequently throughout your article and the title is written below the figure. The reference list should be arranged alphabetically following the guidelines of the Publication Manual of the American Psychological Association (5th ed.. See the following examples:   Book: Ellis, R. (2003. Task-based language learning and teaching. Oxford: Oxford University Press. Internet source: Andrewes, S. (2003. Group work v. whole-class activities. Retrieved October 1, 2012 from http://www.teachingenglish.org

  15. Author Guidelines

    Directory of Open Access Journals (Sweden)

    Yunisrina Qismullah Yusuf

    2015-10-01

    Full Text Available Guidelines for Article Submission   SiELE journal accepts articles on research and development in the field of teaching and learning of English, linguistics, educational development, policy and cultural studies in education. To be considered for publication, the article should be presented in the following system: First page: include a title page with the full title of the paper (must not exceed 16 words, the author(s’ name(s, affiliation(s, phone number(s and e-mail address of the corresponding author. A brief bio-data of the author(s (maximum of 100 words is provided in this page. Second page and subsequent page: Submissions should be between 4000-6000 (including abstract, table(s, figure(s and references in A4 size paper with margins as the following: top 3 cm, bottom 3 cm, right 2.5 cm and left 4 cm. The font is Times New Roman, size 12 and single spaced. The article should generally consist of the following sections: introduction, review of literature, method, findings, discussion and conclusion. Headings and subheadings should be presented as follows (provide a space between the headings and sub-headings. 1         INTRODUCTION 1.1      Subheading of the Content  1.1.1   Subheading of the Content  For Tables, the title size is 12 and the content size is 10. Please number the tables subsequently throughout your article and the title is written above the table. For Figures, the title size is 12 and the content size (if any is 10. Please number the figures subsequently throughout your article and the title is written below the figure. The reference list should be arranged alphabetically following the guidelines of the Publication Manual of the American Psychological Association (5th ed.. See the following examples:   Book: Ellis, R. (2003. Task-based language learning and teaching. Oxford: Oxford University Press. Internet source: Andrewes, S. (2003. Group work v. whole-class activities. Retrieved October 1, 2012 from

  16. Author Guidelines

    Directory of Open Access Journals (Sweden)

    Yunisrina Qismullah Yusuf

    2015-03-01

    Full Text Available Guidelines for Article Submission SiELE journal accepts articles on research and development in the field of teaching and learning of English, linguistics, educational development, policy and cultural studies in education. To be considered for publication, the article should be presented in the following system: First page: include a title page with the full title of the paper (must not exceed 16 words, the author(s’ name(s, affiliation(s, phone number(s and e-mail address of the corresponding author. A brief bio-data of the author(s (maximum of 100 words is provided in this page. Second page and subsequent page: Submissions should be between 4000-6000 (including abstract, table(s, figure(s and references in A4 size paper with margins as the following: top 3 cm, bottom 3 cm, right 2.5 cm and left 4 cm. The font is Times New Roman, size 12 and single spaced. The article should generally consist of the following sections: introduction, review of literature, method, findings, discussion and conclusion. Headings and subheadings should be presented as follows (provide a space between the headings and sub-headings. 1 INTRODUCTION 1.1 Subheading of the content 1.1.1 Subheading of the content For Tables, the title size is 12 and the content size is 10. Please number the tables subsequently throughout your article and the title is written above the table. For Figures, the title size is 12 and the content size (if any is 10. Please number the figures subsequently throughout your article and the title is written below the figure. The reference list should be arranged alphabetically following the guidelines of the Publication Manual of the American Psychological Association (5th ed.. See the following examples: Back Matter| 79 80 | STUDIES IN ENGLISH LANGUAGE AND EDUCATION, Volume 1, Number 1, March 2014 Book: Ellis, R. (2003. Task-based language learning and teaching. Oxford: Oxford University Press. Internet source: Andrewes, S. (2003. Group work v

  17. Author Guidelines

    Directory of Open Access Journals (Sweden)

    Yunisrina Qismullah Yusuf

    2014-03-01

    Full Text Available Guidelines for Article Submission   SiELE journal accepts articles on research and development in the field of teaching and learning of English, linguistics, educational development, policy and cultural studies in education. To be considered for publication, the article should be presented in the following system: First page: include a title page with the full title of the paper (must not exceed 16 words, the author(s’ name(s, affiliation(s, phone number(s and e-mail address of the corresponding author. A brief bio-data of the author(s (maximum of 100 words is provided in this page. Second page and subsequent page: Submissions should be between 4000-6000 (including abstract, table(s, figure(s and references in A4 size paper with margins as the following: top 3 cm, bottom 3 cm, right 2.5 cm and left 4 cm. The font is Times New Roman, size 12 and single spaced. The article should generally consist of the following sections: introduction, review of literature, method, findings, discussion and conclusion. Headings and subheadings should be presented as follows (provide a space between the headings and sub-headings. 1         INTRODUCTION 1.1      Subheading of the content  1.1.1   Subheading of the content  For Tables, the title size is 12 and the content size is 10. Please number the tables subsequently throughout your article and the title is written above the table. For Figures, the title size is 12 and the content size (if any is 10. Please number the figures subsequently throughout your article and the title is written below the figure. The reference list should be arranged alphabetically following the guidelines of the Publication Manual of the American Psychological Association (5th ed.. See the following examples:   Book: Ellis, R. (2003. Task-based language learning and teaching. Oxford: Oxford University Press. Internet source: Andrewes, S. (2003. Group work v. whole-class activities. Retrieved October 1, 2012 from

  18. Evidence in dentistry guidelines

    Directory of Open Access Journals (Sweden)

    Cristiane Rufino Macedo

    Full Text Available CONTEXT AND OBJECTIVE: Guidelines are suggestions for clinical practice based on the best available scientific evidence. Nevertheless, in drafting such guidelines, existing systematic reviews are often ignored and are replaced by general consensuses. This ends up compromising the quality of the instructions through bias. Our objective was to investigate whether Cochrane systematic reviews were present among the bibliographic references of prevention and treatment guidelines for dentistry that have been published in databases. DESIGN AND SETTING: This retrospective, observational study was conducted at the Brazilian Cochrane Center. METHODS: The databases were searched for guidelines. Any guidelines obtained were then checked to find whether Cochrane systematic reviews were present in the bibliographic references of the guidelines. In their absence, we checked whether such reviews had not been included because no reviews existed yet, or because such reviews had not been consulted despite already existing. RESULTS: 223 studies were initially selected; of these, 77 were excluded. Of the 146 guidelines included, 46 could have made reference to existing systematic reviews, but only 13 studies did so. Among these 13 studies, eight were systematic reviews following Cochrane methodology. Thirty-three guidelines had not been drafted using published systematic reviews as references, and 100 guidelines had been unable to use Cochrane references because no reviews existed yet. CONCLUSION: It is necessary to increase awareness of the importance of using systematic reviews in drafting dentistry guidelines. Likewise, it is necessary to develop systematic reviews that answer questions on the various topics that remain unanswered.

  19. A Conceptual Model for Detecting Interactions among Medical Recommendations in Clinical Guidelines

    NARCIS (Netherlands)

    Carretta Zamborlini, Veruska; Da Silveira, Marcos; Pruski, Cedric; Hoekstra, Rinke; ten Teije, Annette; van Harmelen, Frank

    2014-01-01

    Representation of clinical knowledge is still an open research topic. In particular, classical languages designed for representing clinical guidelines, which were meant for producing diagnostic and treatment plans, present limitations such as for re-using, combining, and reasoning over existing

  20. The role of model checking in critiquing based on clinical guidelines

    NARCIS (Netherlands)

    Groot, Perry; Hommersom, Arjen; Lucas, Peter; Serban, Radu; Ten Teije, Annette; Van Harmelen, Frank

    2007-01-01

    Medical critiquing systems criticise clinical actions performed by a physician. In order to provide useful feedback, an important task is to find differences between the actual actions and a set of 'ideal' actions as described by a clinical guideline. In case differences exist, insight to which

  1. Use of the FAO AquaCrop model in developing sowing guidelines ...

    African Journals Online (AJOL)

    2014-03-03

    Mar 3, 2014 ... sowing guidelines for rainfed maize in Zimbabwe. Teddious Mhizha1*, Sam Geerts2, Eline ... from intensification of production in rainfed farming sys- tems. Rockström et al. (2003) showed that it is ...... case, the degree of shading indicates the order of preference for sowing periods. For late sowing, short ...

  2. General analysis of dark radiation in sequestered string models

    Energy Technology Data Exchange (ETDEWEB)

    Cicoli, Michele [ICTP,Strada Costiera 11, Trieste 34014 (Italy); Dipartimento di Fisica e Astronomia, Università di Bologna,via Irnerio 46, 40126 Bologna (Italy); INFN, Sezione di Bologna,via Irnerio 46, 40126 Bologna (Italy); Muia, Francesco [Dipartimento di Fisica e Astronomia, Università di Bologna,via Irnerio 46, 40126 Bologna (Italy); INFN, Sezione di Bologna,via Irnerio 46, 40126 Bologna (Italy)

    2015-12-22

    We perform a general analysis of axionic dark radiation produced from the decay of the lightest modulus in the sequestered LARGE Volume Scenario. We discuss several cases depending on the form of the Kähler metric for visible sector matter fields and the mechanism responsible for achieving a de Sitter vacuum. The leading decay channels which determine dark radiation predictions are to hidden sector axions, visible sector Higgses and SUSY scalars depending on their mass. We show that in most of the parameter space of split SUSY-like models squarks and sleptons are heavier than the lightest modulus. Hence dark radiation predictions previously obtained for MSSM-like cases hold more generally also for split SUSY-like cases since the decay channel to SUSY scalars is kinematically forbidden. However the inclusion of string loop corrections to the Kähler potential gives rise to a parameter space region where the decay channel to SUSY scalars opens up, leading to a significant reduction of dark radiation production. In this case, the simplest model with a shift-symmetric Higgs sector can suppress the excess of dark radiation ΔN{sub eff} to values as small as 0.14, in perfect agreement with current experimental bounds. Depending on the exact mass of the SUSY scalars all values in the range 0.14≲ΔN{sub eff}≲1.6 are allowed. Interestingly dark radiation overproduction can be avoided also in the absence of a Giudice-Masiero coupling.

  3. Modeling containment of large wildfires using generalized linear mixed-model analysis

    Science.gov (United States)

    Mark Finney; Isaac C. Grenfell; Charles W. McHugh

    2009-01-01

    Billions of dollars are spent annually in the United States to contain large wildland fires, but the factors contributing to suppression success remain poorly understood. We used a regression model (generalized linear mixed-model) to model containment probability of individual fires, assuming that containment was a repeated-measures problem (fixed effect) and...

  4. Concept Note General Guidelines - English

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

    NCDP

    Estimated Expenses. Personnel. Consultants. Evaluation. Equipment. International travel. Research expenses. Indirect project costs (maximum 13%). Total ... IDRC may pay the replacement cost (release me for academics) of principal ... In such cases, IDRC will only cover the payroll cost of the replacement (usually a lower.

  5. Diabatic models with transferrable parameters for generalized chemical reactions

    Science.gov (United States)

    Reimers, Jeffrey R.; McKemmish, Laura K.; McKenzie, Ross H.; Hush, Noel S.

    2017-05-01

    Diabatic models applied to adiabatic electron-transfer theory yield many equations involving just a few parameters that connect ground-state geometries and vibration frequencies to excited-state transition energies and vibration frequencies to the rate constants for electron-transfer reactions, utilizing properties of the conical-intersection seam linking the ground and excited states through the Pseudo Jahn-Teller effect. We review how such simplicity in basic understanding can also be obtained for general chemical reactions. The key feature that must be recognized is that electron-transfer (or hole transfer) processes typically involve one electron (hole) moving between two orbitals, whereas general reactions typically involve two electrons or even four electrons for processes in aromatic molecules. Each additional moving electron leads to new high-energy but interrelated conical-intersection seams that distort the shape of the critical lowest-energy seam. Recognizing this feature shows how conical-intersection descriptors can be transferred between systems, and how general chemical reactions can be compared using the same set of simple parameters. Mathematical relationships are presented depicting how different conical-intersection seams relate to each other, showing that complex problems can be reduced into an effective interaction between the ground-state and a critical excited state to provide the first semi-quantitative implementation of Shaik’s “twin state” concept. Applications are made (i) demonstrating why the chemistry of the first-row elements is qualitatively so different to that of the second and later rows, (ii) deducing the bond-length alternation in hypothetical cyclohexatriene from the observed UV spectroscopy of benzene, (iii) demonstrating that commonly used procedures for modelling surface hopping based on inclusion of only the first-derivative correction to the Born-Oppenheimer approximation are valid in no region of the chemical

  6. Generalized Potential Energy Finite Elements for Modeling Molecular Nanostructures.

    Science.gov (United States)

    Chatzieleftheriou, Stavros; Adendorff, Matthew R; Lagaros, Nikos D

    2016-10-24

    The potential energy of molecules and nanostructures is commonly calculated in the molecular mechanics formalism by superimposing bonded and nonbonded atomic energy terms, i.e. bonds between two atoms, bond angles involving three atoms, dihedral angles involving four atoms, nonbonded terms expressing the Coulomb and Lennard-Jones interactions, etc. In this work a new, generalized numerical simulation is presented for studying the mechanical behavior of three-dimensional nanostructures at the atomic scale. The energy gradient and Hessian matrix of such assemblies are usually computed numerically; a potential energy finite element model is proposed herein where these two components are expressed analytically. In particular, generalized finite elements are developed that express the interactions among atoms in a manner equivalent to that invoked in simulations performed based on the molecular dynamics method. Thus, the global tangent stiffness matrix for any nanostructure is formed as an assembly of the generalized finite elements and is directly equivalent to the Hessian matrix of the potential energy. The advantages of the proposed model are identified in terms of both accuracy and computational efficiency. In the case of popular force fields (e.g., CHARMM), the computation of the Hessian matrix by implementing the proposed method is of the same order as that of the gradient. This analysis can be used to minimize the potential energy of molecular systems under nodal loads in order to derive constitutive laws for molecular systems where the entropy and solvent effects are neglected and can be approximated as solids, such as double stranded DNA nanostructures. In this context, the sequence dependent stretch modulus for some typical base pairs step is calculated.

  7. Designing a Wien Filter Model with General Particle Tracer

    Science.gov (United States)

    Mitchell, John; Hofler, Alicia

    2017-09-01

    The Continuous Electron Beam Accelerator Facility injector employs a beamline component called a Wien filter which is typically used to select charged particles of a certain velocity. The Wien filter is also used to rotate the polarization of a beam for parity violation experiments. The Wien filter consists of perpendicular electric and magnetic fields. The electric field changes the spin orientation, but also imposes a transverse kick which is compensated for by the magnetic field. The focus of this project was to create a simulation of the Wien filter using General Particle Tracer. The results from these simulations were vetted against machine data to analyze the accuracy of the Wien model. Due to the close agreement between simulation and experiment, the data suggest that the Wien filter model is accurate. The model allows a user to input either the desired electric or magnetic field of the Wien filter along with the beam energy as parameters, and is able to calculate the perpendicular field strength required to keep the beam on axis. The updated model will aid in future diagnostic tests of any beamline component downstream of the Wien filter, and allow users to easily calculate the electric and magnetic fields needed for the filter to function properly. Funding support provided by DOE Office of Science's Student Undergraduate Laboratory Internship program.

  8. Singular solitons of generalized Camassa-Holm models

    International Nuclear Information System (INIS)

    Tian Lixin; Sun Lu

    2007-01-01

    Two generalizations of the Camassa-Holm system associated with the singular analysis are proposed for Painleve integrability properties and the extensions of already known analytic solitons. A remarkable feature of the physical model is that it has peakon solution which has peak form. An alternative WTC test which allowed the identifying of such models directly if formulated in terms of inserting a formed ansatz into these models. For the two models have Painleve property, Painleve-Baecklund systems can be constructed through the expansion of solitons about the singularity manifold. By the implementations of Maple, plentiful new type solitonic structures and some kink waves, which are affected by the variation of energy, are explored. If the energy is infinite in finite time, there will be a collapse in soliton systems by direct numerical simulations. Particularly, there are two collapses coexisting in our regular solitons, which occurred around its central regions. Simulation shows that in the bottom of periodic waves arises the non-zero parts of compactons and anti-compactons. We also get floating solitary waves whose amplitude is infinite. In contrary to which a finite-amplitude blow-up soliton is obtained. Periodic blow-ups are found too. Special kinks which have periodic cuspons are derived

  9. General Description of Fission Observables - JEFF Report 24. GEF Model

    International Nuclear Information System (INIS)

    Schmidt, Karl-Heinz; Jurado, Beatriz; Amouroux, Charlotte

    2014-06-01

    The Joint Evaluated Fission and Fusion (JEFF) Project is a collaborative effort among the member countries of the OECD Nuclear Energy Agency (NEA) Data Bank to develop a reference nuclear data library. The JEFF library contains sets of evaluated nuclear data, mainly for fission and fusion applications; it contains a number of different data types, including neutron and proton interaction data, radioactive decay data, fission yield data and thermal scattering law data. The General fission (GEF) model is based on novel theoretical concepts and ideas developed to model low energy nuclear fission. The GEF code calculates fission-fragment yields and associated quantities (e.g. prompt neutron and gamma) for a large range of nuclei and excitation energy. This opens up the possibility of a qualitative step forward to improve further the JEFF fission yields sub-library. This report describes the GEF model which explains the complex appearance of fission observables by universal principles of theoretical models and considerations on the basis of fundamental laws of physics and mathematics. The approach reveals a high degree of regularity and provides a considerable insight into the physics of the fission process. Fission observables can be calculated with a precision that comply with the needs for applications in nuclear technology. The relevance of the approach for examining the consistency of experimental results and for evaluating nuclear data is demonstrated. (authors)

  10. Generalized PSF modeling for optimized quantitation in PET imaging

    Science.gov (United States)

    Ashrafinia, Saeed; Mohy-ud-Din, Hassan; Karakatsanis, Nicolas A.; Jha, Abhinav K.; Casey, Michael E.; Kadrmas, Dan J.; Rahmim, Arman

    2017-06-01

    modeling does not offer optimized PET quantitation, and that PSF overestimation may provide enhanced SUV quantitation. Furthermore, generalized PSF modeling may provide a valuable approach for quantitative tasks such as treatment-response assessment and prognostication.

  11. Complex Environmental Data Modelling Using Adaptive General Regression Neural Networks

    Science.gov (United States)

    Kanevski, Mikhail

    2015-04-01

    The research deals with an adaptation and application of Adaptive General Regression Neural Networks (GRNN) to high dimensional environmental data. GRNN [1,2,3] are efficient modelling tools both for spatial and temporal data and are based on nonparametric kernel methods closely related to classical Nadaraya-Watson estimator. Adaptive GRNN, using anisotropic kernels, can be also applied for features selection tasks when working with high dimensional data [1,3]. In the present research Adaptive GRNN are used to study geospatial data predictability and relevant feature selection using both simulated and real data case studies. The original raw data were either three dimensional monthly precipitation data or monthly wind speeds embedded into 13 dimensional space constructed by geographical coordinates and geo-features calculated from digital elevation model. GRNN were applied in two different ways: 1) adaptive GRNN with the resulting list of features ordered according to their relevancy; and 2) adaptive GRNN applied to evaluate all possible models N [in case of wind fields N=(2^13 -1)=8191] and rank them according to the cross-validation error. In both cases training were carried out applying leave-one-out procedure. An important result of the study is that the set of the most relevant features depends on the month (strong seasonal effect) and year. The predictabilities of precipitation and wind field patterns, estimated using the cross-validation and testing errors of raw and shuffled data, were studied in detail. The results of both approaches were qualitatively and quantitatively compared. In conclusion, Adaptive GRNN with their ability to select features and efficient modelling of complex high dimensional data can be widely used in automatic/on-line mapping and as an integrated part of environmental decision support systems. 1. Kanevski M., Pozdnoukhov A., Timonin V. Machine Learning for Spatial Environmental Data. Theory, applications and software. EPFL Press

  12. General Description of Fission Observables: GEF Model Code

    Science.gov (United States)

    Schmidt, K.-H.; Jurado, B.; Amouroux, C.; Schmitt, C.

    2016-01-01

    The GEF ("GEneral description of Fission observables") model code is documented. It describes the observables for spontaneous fission, neutron-induced fission and, more generally, for fission of a compound nucleus from any other entrance channel, with given excitation energy and angular momentum. The GEF model is applicable for a wide range of isotopes from Z = 80 to Z = 112 and beyond, up to excitation energies of about 100 MeV. The results of the GEF model are compared with fission barriers, fission probabilities, fission-fragment mass- and nuclide distributions, isomeric ratios, total kinetic energies, and prompt-neutron and prompt-gamma yields and energy spectra from neutron-induced and spontaneous fission. Derived properties of delayed neutrons and decay heat are also considered. The GEF model is based on a general approach to nuclear fission that explains a great part of the complex appearance of fission observables on the basis of fundamental laws of physics and general properties of microscopic systems and mathematical objects. The topographic theorem is used to estimate the fission-barrier heights from theoretical macroscopic saddle-point and ground-state masses and experimental ground-state masses. Motivated by the theoretically predicted early localisation of nucleonic wave functions in a necked-in shape, the properties of the relevant fragment shells are extracted. These are used to determine the depths and the widths of the fission valleys corresponding to the different fission channels and to describe the fission-fragment distributions and deformations at scission by a statistical approach. A modified composite nuclear-level-density formula is proposed. It respects some features in the superfluid regime that are in accordance with new experimental findings and with theoretical expectations. These are a constant-temperature behaviour that is consistent with a considerably increased heat capacity and an increased pairing condensation energy that is

  13. A general formulation for a mathematical PEM fuel cell model

    Science.gov (United States)

    Baschuk, J. J.; Li, Xianguo

    A general formulation for a comprehensive fuel cell model, based on the conservation principle is presented. The model formulation includes the electro-chemical reactions, proton migration, and the mass transport of the gaseous reactants and liquid water. Additionally, the model formulation can be applied to all regions of the PEM fuel cell: the bipolar plates, gas flow channels, electrode backing, catalyst, and polymer electrolyte layers. The model considers the PEM fuel cell to be composed of three phases: reactant gas, liquid water, and solid. These three phases can co-exist within the gas flow channels, electrode backing, catalyst, and polymer electrolyte layers. The conservation of mass, momentum, species, and energy are applied to each phase, with the technique of volume averaging being used to incorporate the interactions between the phases as interfacial source terms. In order to avoid problems arising from phase discontinuities, the gas and liquid phases are considered as a mixture. The momentum interactions between the fluid and solid phases are modeled by the Darcy-Forchheimer term. The electro-oxidation of H and CO, the reduction of O, and the heterogeneous oxidation of H and CO are considered in the catalyst layers. Due to the small pore size of the polymer electrolyte layer, the generalized Stefan-Maxwell equations, with the polymer considered as a diffusing species, are used to describe species transport. One consequence of considering the gas and liquid phases as a mixture is that expressions for the velocity of the individual phases relative to the mixture must be developed. In the gas flow channels, the flow is assumed homogeneous, while the Darcy and Schlögl equations are used to describe liquid water transport in the electrode backing and polymer electrolyte layers. Thus, two sets of equations, one for the mixture and another for the solid phase, can be developed to describe the processes occurring within a PEM fuel cell. These equations are in

  14. Extending the linear model with R generalized linear, mixed effects and nonparametric regression models

    CERN Document Server

    Faraway, Julian J

    2005-01-01

    Linear models are central to the practice of statistics and form the foundation of a vast range of statistical methodologies. Julian J. Faraway''s critically acclaimed Linear Models with R examined regression and analysis of variance, demonstrated the different methods available, and showed in which situations each one applies. Following in those footsteps, Extending the Linear Model with R surveys the techniques that grow from the regression model, presenting three extensions to that framework: generalized linear models (GLMs), mixed effect models, and nonparametric regression models. The author''s treatment is thoroughly modern and covers topics that include GLM diagnostics, generalized linear mixed models, trees, and even the use of neural networks in statistics. To demonstrate the interplay of theory and practice, throughout the book the author weaves the use of the R software environment to analyze the data of real examples, providing all of the R commands necessary to reproduce the analyses. All of the ...

  15. Generalized multiplicative error models: Asymptotic inference and empirical analysis

    Science.gov (United States)

    Li, Qian

    This dissertation consists of two parts. The first part focuses on extended Multiplicative Error Models (MEM) that include two extreme cases for nonnegative series. These extreme cases are common phenomena in high-frequency financial time series. The Location MEM(p,q) model incorporates a location parameter so that the series are required to have positive lower bounds. The estimator for the location parameter turns out to be the minimum of all the observations and is shown to be consistent. The second case captures the nontrivial fraction of zero outcomes feature in a series and combines a so-called Zero-Augmented general F distribution with linear MEM(p,q). Under certain strict stationary and moment conditions, we establish a consistency and asymptotic normality of the semiparametric estimation for these two new models. The second part of this dissertation examines the differences and similarities between trades in the home market and trades in the foreign market of cross-listed stocks. We exploit the multiplicative framework to model trading duration, volume per trade and price volatility for Canadian shares that are cross-listed in the New York Stock Exchange (NYSE) and the Toronto Stock Exchange (TSX). We explore the clustering effect, interaction between trading variables, and the time needed for price equilibrium after a perturbation for each market. The clustering effect is studied through the use of univariate MEM(1,1) on each variable, while the interactions among duration, volume and price volatility are captured by a multivariate system of MEM(p,q). After estimating these models by a standard QMLE procedure, we exploit the Impulse Response function to compute the calendar time for a perturbation in these variables to be absorbed into price variance, and use common statistical tests to identify the difference between the two markets in each aspect. These differences are of considerable interest to traders, stock exchanges and policy makers.

  16. A Pacific Ocean general circulation model for satellite data assimilation

    Science.gov (United States)

    Chao, Y.; Halpern, D.; Mechoso, C. R.

    1991-01-01

    A tropical Pacific Ocean General Circulation Model (OGCM) to be used in satellite data assimilation studies is described. The transfer of the OGCM from a CYBER-205 at NOAA's Geophysical Fluid Dynamics Laboratory to a CRAY-2 at NASA's Ames Research Center is documented. Two 3-year model integrations from identical initial conditions but performed on those two computers are compared. The model simulations are very similar to each other, as expected, but the simulations performed with the higher-precision CRAY-2 is smoother than that with the lower-precision CYBER-205. The CYBER-205 and CRAY-2 use 32 and 64-bit mantissa arithmetic, respectively. The major features of the oceanic circulation in the tropical Pacific, namely the North Equatorial Current, the North Equatorial Countercurrent, the South Equatorial Current, and the Equatorial Undercurrent, are realistically produced and their seasonal cycles are described. The OGCM provides a powerful tool for study of tropical oceans and for the assimilation of satellite altimetry data.

  17. General relativity cosmological models without the big bang

    International Nuclear Information System (INIS)

    Rosen, N.

    1985-01-01

    Attention is given to the so-called standard model of the universe in the framework of the general theory of relativity. This model is taken to be homogeneous and isotropic and filled with an ideal fluid characterized by a density and a pressure. Taking into consideration, however, the assumption that the universe began in a singular state, it is found hard to understand why the universe is so nearly homogeneous and isotropic at present for a singularity represents a breakdown of physical laws, and the initial singularity cannot, therefore, predetermine the subsequent symmetries of the universe. The present investigation has the objective to find a way of avoiding this initial singularity, i.e., to look for a cosmological model without the big bang. The idea is proposed that there exists a limiting density of matter of the order of magnitude of the Planck density, and that this was the density of matter at the moment at which the universe began to expand

  18. A generalized model for estimating the energy density of invertebrates

    Science.gov (United States)

    James, Daniel A.; Csargo, Isak J.; Von Eschen, Aaron; Thul, Megan D.; Baker, James M.; Hayer, Cari-Ann; Howell, Jessica; Krause, Jacob; Letvin, Alex; Chipps, Steven R.

    2012-01-01

    Invertebrate energy density (ED) values are traditionally measured using bomb calorimetry. However, many researchers rely on a few published literature sources to obtain ED values because of time and sampling constraints on measuring ED with bomb calorimetry. Literature values often do not account for spatial or temporal variability associated with invertebrate ED. Thus, these values can be unreliable for use in models and other ecological applications. We evaluated the generality of the relationship between invertebrate ED and proportion of dry-to-wet mass (pDM). We then developed and tested a regression model to predict ED from pDM based on a taxonomically, spatially, and temporally diverse sample of invertebrates representing 28 orders in aquatic (freshwater, estuarine, and marine) and terrestrial (temperate and arid) habitats from 4 continents and 2 oceans. Samples included invertebrates collected in all seasons over the last 19 y. Evaluation of these data revealed a significant relationship between ED and pDM (r2  =  0.96, p cost savings compared to traditional bomb calorimetry approaches. This model should prove useful for a wide range of ecological studies because it is unaffected by taxonomic, seasonal, or spatial variability.

  19. Application of conditional moment tests to model checking for generalized linear models.

    Science.gov (United States)

    Pan, Wei

    2002-06-01

    Generalized linear models (GLMs) are increasingly being used in daily data analysis. However, model checking for GLMs with correlated discrete response data remains difficult. In this paper, through a case study on marginal logistic regression using a real data set, we illustrate the flexibility and effectiveness of using conditional moment tests (CMTs), along with other graphical methods, to do model checking for generalized estimation equation (GEE) analyses. Although CMTs provide an array of powerful diagnostic tests for model checking, they were originally proposed in the econometrics literature and, to our knowledge, have never been applied to GEE analyses. CMTs cover many existing tests, including the (generalized) score test for an omitted covariate, as special cases. In summary, we believe that CMTs provide a class of useful model checking tools.

  20. Spin squeezing in a generalized one-axis twisting model

    Science.gov (United States)

    Jin, Guang-Ri; Liu, Yong-Chun; Liu, Wu-Ming

    2009-07-01

    We investigate the dependence of spin squeezing on the polar angle of the initial coherent spin state |θ0, phi0rang in a generalized one-axis twisting model, where the detuning δ is taken into account. We show explicitly that regardless of δ and phi0, previous results of the ideal one-axis twisting are recovered as long as θ0=π/2. For a small departure of θ0 from π/2, however, the achievable variance (V -)min ~N2/3, which is larger than the ideal case N1/3. We also find that the maximal squeezing time tmin scales as N-5/6. Analytic expressions of (V-)min and tmin are presented and they agree with numerical simulations.

  1. dglars: An R Package to Estimate Sparse Generalized Linear Models

    Directory of Open Access Journals (Sweden)

    Luigi Augugliaro

    2014-09-01

    Full Text Available dglars is a publicly available R package that implements the method proposed in Augugliaro, Mineo, and Wit (2013, developed to study the sparse structure of a generalized linear model. This method, called dgLARS, is based on a differential geometrical extension of the least angle regression method proposed in Efron, Hastie, Johnstone, and Tibshirani (2004. The core of the dglars package consists of two algorithms implemented in Fortran 90 to efficiently compute the solution curve: a predictor-corrector algorithm, proposed in Augugliaro et al. (2013, and a cyclic coordinate descent algorithm, proposed in Augugliaro, Mineo, and Wit (2012. The latter algorithm, as shown here, is significantly faster than the predictor-corrector algorithm. For comparison purposes, we have implemented both algorithms.

  2. A general Bayes weibull inference model for accelerated life testing

    International Nuclear Information System (INIS)

    Dorp, J. Rene van; Mazzuchi, Thomas A.

    2005-01-01

    This article presents the development of a general Bayes inference model for accelerated life testing. The failure times at a constant stress level are assumed to belong to a Weibull distribution, but the specification of strict adherence to a parametric time-transformation function is not required. Rather, prior information is used to indirectly define a multivariate prior distribution for the scale parameters at the various stress levels and the common shape parameter. Using the approach, Bayes point estimates as well as probability statements for use-stress (and accelerated) life parameters may be inferred from a host of testing scenarios. The inference procedure accommodates both the interval data sampling strategy and type I censored sampling strategy for the collection of ALT test data. The inference procedure uses the well-known MCMC (Markov Chain Monte Carlo) methods to derive posterior approximations. The approach is illustrated with an example

  3. Generalized Swept Mid-structure for Polygonal Models

    KAUST Repository

    Martin, Tobias

    2012-05-01

    We introduce a novel mid-structure called the generalized swept mid-structure (GSM) of a closed polygonal shape, and a framework to compute it. The GSM contains both curve and surface elements and has consistent sheet-by-sheet topology, versus triangle-by-triangle topology produced by other mid-structure methods. To obtain this structure, a harmonic function, defined on the volume that is enclosed by the surface, is used to decompose the volume into a set of slices. A technique for computing the 1D mid-structures of these slices is introduced. The mid-structures of adjacent slices are then iteratively matched through a boundary similarity computation and triangulated to form the GSM. This structure respects the topology of the input surface model is a hybrid mid-structure representation. The construction and topology of the GSM allows for local and global simplification, used in further applications such as parameterization, volumetric mesh generation and medical applications.

  4. Modelling the likely impact of healthy eating guidelines on agriculture in England and Wales

    OpenAIRE

    Arnoult, Matthieu H.; Jones, Philip J.; Tranter, Richard B.; Tiffin, J. Richard; Traill, W. Bruce

    2008-01-01

    Household food consumption data is used to estimate likely changes in diet under healthy eating guidelines, and the consequences this would have on the agricultural sector in England and Wales. The first step entails imposing nutrient restrictions on food consumption following dietary recommendations. The resulting diet is then used as a proxy for demand in agricultural commodities, to test the impact of such a scenario on agricultural land use and production. Results of the diet optimisation...

  5. Cannabinoid Hyperemesis Syndrome: Public Health Implications and a Novel Model Treatment Guideline

    Directory of Open Access Journals (Sweden)

    Seth Meyer

    2017-11-01

    Full Text Available Introduction: Cannabinoid hyperemesis syndrome (CHS is an entity associated with cannabinoid overuse. CHS typically presents with cyclical vomiting, diffuse abdominal pain, and relief with hot showers. Patients often present to the emergency department (ED repeatedly and undergo extensive evaluations including laboratory examination, advanced imaging, and in some cases unnecessary procedures. They are exposed to an array of pharmacologic interventions including opioids that not only lack evidence, but may also be harmful. This paper presents a novel treatment guideline that highlights the identification and diagnosis of CHS and summarizes treatment strategies aimed at resolution of symptoms, avoidance of unnecessary opioids, and ensuring patient safety. Methods: The San Diego Emergency Medicine Oversight Commission in collaboration with the County of San Diego Health and Human Services Agency and San Diego Kaiser Permanente Division of Medical Toxicology created an expert consensus panel to establish a guideline to unite the ED community in the treatment of CHS. Results: Per the consensus guideline, treatment should focus on symptom relief and education on the need for cannabis cessation. Capsaicin is a readily available topical preparation that is reasonable to use as first-line treatment. Antipsychotics including haloperidol and olanzapine have been reported to provide complete symptom relief in limited case studies. Conventional antiemetics including antihistamines, serotonin antagonists, dopamine antagonists and benzodiazepines may have limited effectiveness. Emergency physicians should avoid opioids if the diagnosis of CHS is certain and educate patients that cannabis cessation is the only intervention that will provide complete symptom relief. Conclusion: An expert consensus treatment guideline is provided to assist with diagnosis and appropriate treatment of CHS. Clinicians and public health officials should identity and treat CHS

  6. Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

    International Nuclear Information System (INIS)

    Simmons, C.S.; Cole, C.R.

    1985-05-01

    This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds. An executive summary, published separately, gives managers and site operators an overview of the main guideline report. This volume includes specific recommendations for decision-making managers and site operators on how to use these guidelines. The more detailed discussions about the code selection approach are provided. 242 refs., 6 figs

  7. A markov model approach assessing the cost of illness of generalized anxiety disorder in Canada.

    Science.gov (United States)

    Bereza, Basil G; Machado, Márcio; Papadimitropoulos, Manny; Sproule, Beth; Ravindran, Arun V; Einarson, Thomas R

    2012-12-01

    Generalized anxiety disorder (GAD) is a chronic disease with waxing and waning of symptoms. This is the first comprehensive economic model developed to reflect the nature and course of GAD. An incidence-based probabilistic Markov model was developed reflecting nine GAD health states (HS): clinical assessments (three HS), maintenance therapies (four HS), discontinuation (one HS), and death (one HS). A probability curve of the GAD onset (ages 18-80) determined entry into the model and assumed patients retained the diagnoses until death. Canadian Psychiatric Association (CPA) guidelines determined pharmacotherapy, with revisions/validation by an expert panel. Direct costs (clinician, pharmacotherapy, hospitalization) were retrieved from government publications. Remission was based on pooled-analysis of CPA-cited evidence. Remaining clinical rates, absenteeism, and hospitalization were retrieved from the literature. Direct costs were attributed throughout the model except for the discontinuation and death HS. Indirect costs (wage rate) were retrieved from government publications and the literature (absenteeism), and were attributed to patients with GAD ≤65 years of age. Results were discounted at 5% and results expressed in 2008 Canadian dollars. The mean lifetime cost of illness (COI) was estimated to be $31,213 (SD $9,100) per patient. The cost of absenteeism accounted for 96% of the mean COI. The mean age of onset was 31 years and approximately 19% did not respond to pharmacotherapy. Over 85% of patients discontinued treatment by the fourth cycle (2nd year of therapy). Over the course of the model, a mean of 53% of patients relapsed, with an average rate of 0.79 relapses per patient. On average and over a lifetime, the disorder went unmanaged over a period of 14 (SD 9) years. The model was most sensitive to absenteeism. GAD is a costly disease with a lifetime COI <$32k/patient, with absenteeism exerting a significant impact.

  8. A summary of hazard datasets and guidelines supported by the Global Earthquake Model during the first implementation phase

    Directory of Open Access Journals (Sweden)

    Marco Pagani

    2015-04-01

    Full Text Available The Global Earthquake Model (GEM initiative promotes open, transparent and collaborative science aimed at the assessment of earthquake risk and its reduction worldwide. During the first implementation phase (2009-2014 GEM sponsored five projects aimed at the creation of global datasets and guidelines toward the creation of open, transparent and, as far as possible, homogeneous hazard input models. These projects concentrated on the following global databases and models: an instrumental catalogue, a historical earthquake archive and catalogue, a geodetic strain rate model, a database of active faults, and set of ground motion prediction equations. This paper describes the main outcomes of these projects illustrating some initial applications as well as challenges in the creation of hazard models.

  9. A generalized methodology for identification of threshold for HRU delineation in SWAT model

    Science.gov (United States)

    M, J.; Sudheer, K.; Chaubey, I.; Raj, C.

    2016-12-01

    The distributed hydrological model, Soil and Water Assessment Tool (SWAT) is a comprehensive hydrologic model widely used for making various decisions. The simulation accuracy of the distributed hydrological model differs due to the mechanism involved in the subdivision of the watershed. Soil and Water Assessment Tool (SWAT) considers sub-dividing the watershed and the sub-basins into small computing units known as 'hydrologic response units (HRU). The delineation of HRU is done based on unique combinations of land use, soil types, and slope within the sub-watersheds, which are not spatially defined. The computations in SWAT are done at HRU level and are then aggregated up to the sub-basin outlet, which is routed through the stream system. Generally, the HRUs are delineated by considering a threshold percentage of land use, soil and slope are to be given by the modeler to decrease the computation time of the model. The thresholds constrain the minimum area for constructing an HRU. In the current HRU delineation practice in SWAT, the land use, soil and slope of the watershed within a sub-basin, which is less than the predefined threshold, will be surpassed by the dominating land use, soil and slope, and introduce some level of ambiguity in the process simulations in terms of inappropriate representation of the area. But the loss of information due to variation in the threshold values depends highly on the purpose of the study. Therefore this research studies the effects of threshold values of HRU delineation on the hydrological modeling of SWAT on sediment simulations and suggests guidelines for selecting the appropriate threshold values considering the sediment simulation accuracy. The preliminary study was done on Illinois watershed by assigning different thresholds for land use and soil. A general methodology was proposed for identifying an appropriate threshold for HRU delineation in SWAT model that considered computational time and accuracy of the simulation

  10. [The practice guideline 'Lower urinary-tract symptoms in middle-aged and elderly men' (second revision) from the Dutch College of General Practitioners; a response from the perspective of urology

    NARCIS (Netherlands)

    Gils, M.P. van; Mulders, P.F.A.

    2005-01-01

    New insights in the fields of terminology, diagnosis and treatment have been successfully implemented in the second revision of the practice guideline 'Lower urinary-tract symptoms in middle-aged and elderly men' from the Dutch College of General Practitioners. The result is a coherent, lucid and

  11. The Internal/External Frame of Reference Model Revisited: Incorporating General Cognitive Ability and General Academic Self-Concept.

    Science.gov (United States)

    Brunner, Martin; Lüdtke, Oliver; Trautwein, Ulrich

    2008-01-01

    The internal/external frame of reference model (I/E model; Marsh, 1986 ) is a highly influential model of self-concept formation, which predicts that domain-specific abilities have positive effects on academic self-concepts in the corresponding domain and negative effects across domains. Investigations of the I/E model do not typically incorporate general cognitive ability or general academic self-concept. This article investigates alternative measurement models for domain-specific and domain-general cognitive abilities and academic self-concepts within an extended I/E model framework using representative data from 25,301 9th-grade students. Empirical support was found for the external validity of a new measurement model for academic self-concepts with respect to key student characteristics (gender, school satisfaction, educational aspirations, domain-specific interests, grades). Moreover, the basic predictions of the I/E model were confirmed, and the new extension of the traditional I/E model permitted meaningful relations to be drawn between domain-general cognitive ability and domain-general academic self-concept as well as between the domain-specific elements of the model.

  12. Digital terrain model generalization incorporating scale, semantic and cognitive constraints

    Science.gov (United States)

    Partsinevelos, Panagiotis; Papadogiorgaki, Maria

    2014-05-01

    Cartographic generalization is a well-known process accommodating spatial data compression, visualization and comprehension under various scales. In the last few years, there are several international attempts to construct tangible GIS systems, forming real 3D surfaces using a vast number of mechanical parts along a matrix formation (i.e., bars, pistons, vacuums). Usually, moving bars upon a structured grid push a stretching membrane resulting in a smooth visualization for a given surface. Most of these attempts suffer either in their cost, accuracy, resolution and/or speed. Under this perspective, the present study proposes a surface generalization process that incorporates intrinsic constrains of tangible GIS systems including robotic-motor movement and surface stretching limitations. The main objective is to provide optimized visualizations of 3D digital terrain models with minimum loss of information. That is, to minimize the number of pixels in a raster dataset used to define a DTM, while reserving the surface information. This neighborhood type of pixel relations adheres to the basics of Self Organizing Map (SOM) artificial neural networks, which are often used for information abstraction since they are indicative of intrinsic statistical features contained in the input patterns and provide concise and characteristic representations. Nevertheless, SOM remains more like a black box procedure not capable to cope with possible particularities and semantics of the application at hand. E.g. for coastal monitoring applications, the near - coast areas, surrounding mountains and lakes are more important than other features and generalization should be "biased"-stratified to fulfill this requirement. Moreover, according to the application objectives, we extend the SOM algorithm to incorporate special types of information generalization by differentiating the underlying strategy based on topologic information of the objects included in the application. The final

  13. Structural Modeling of Measurement Error in Generalized Linear Models with Rasch Measures as Covariates

    Science.gov (United States)

    Battauz, Michela; Bellio, Ruggero

    2011-01-01

    This paper proposes a structural analysis for generalized linear models when some explanatory variables are measured with error and the measurement error variance is a function of the true variables. The focus is on latent variables investigated on the basis of questionnaires and estimated using item response theory models. Latent variable…

  14. To transform or not to transform: using generalized linear mixed models to analyse reaction time data

    Science.gov (United States)

    Lo, Steson; Andrews, Sally

    2015-01-01

    Linear mixed-effect models (LMMs) are being increasingly widely used in psychology to analyse multi-level research designs. This feature allows LMMs to address some of the problems identified by Speelman and McGann (2013) about the use of mean data, because they do not average across individual responses. However, recent guidelines for using LMM to analyse skewed reaction time (RT) data collected in many cognitive psychological studies recommend the application of non-linear transformations to satisfy assumptions of normality. Uncritical adoption of this recommendation has important theoretical implications which can yield misleading conclusions. For example, Balota et al. (2013) showed that analyses of raw RT produced additive effects of word frequency and stimulus quality on word identification, which conflicted with the interactive effects observed in analyses of transformed RT. Generalized linear mixed-effect models (GLMM) provide a solution to this problem by satisfying normality assumptions without the need for transformation. This allows differences between individuals to be properly assessed, using the metric most appropriate to the researcher's theoretical context. We outline the major theoretical decisions involved in specifying a GLMM, and illustrate them by reanalysing Balota et al.'s datasets. We then consider the broader benefits of using GLMM to investigate individual differences. PMID:26300841

  15. A Comparison of Generalized Hyperbolic Distribution Models for Equity Returns

    Directory of Open Access Journals (Sweden)

    Virginie Konlack Socgnia

    2014-01-01

    Full Text Available We discuss the calibration of the univariate and multivariate generalized hyperbolic distributions, as well as their hyperbolic, variance gamma, normal inverse Gaussian, and skew Student’s t-distribution subclasses for the daily log-returns of seven of the most liquid mining stocks listed on the Johannesburg Stocks Exchange. To estimate the model parameters from historic distributions, we use an expectation maximization based algorithm for the univariate case and a multicycle expectation conditional maximization estimation algorithm for the multivariate case. We assess the goodness of fit statistics using the log-likelihood, the Akaike information criterion, and the Kolmogorov-Smirnov distance. Finally, we inspect the temporal stability of parameters and note implications as criteria for distinguishing between models. To better understand the dependence structure of the stocks, we fit the MGHD and subclasses to both the stock returns and the two leading principal components derived from the price data. While the MGHD could fit both data subsets, we observed that the multivariate normality of the stock return residuals, computed by removing shared components, suggests that the departure from normality can be explained by the structure in the common factors.

  16. Prognostic cloud water in the Los Alamos general circulation model

    International Nuclear Information System (INIS)

    Kristjansson, J.E.; Kao, C.Y.J.

    1993-01-01

    Most of today's general circulation models (GCMS) have a greatly simplified treatment of condensation and clouds. Recent observational studies of the earth's radiation budget have suggested cloud-related feedback mechanisms to be of tremendous importance for the issue of global change. Thus, there has arisen an urgent need for improvements in the treatment of clouds in GCMS, especially as the clouds relate to radiation. In the present paper, we investigate the effects of introducing pregnostic cloud water into the Los Alamos GCM. The cloud water field, produced by both stratiform and convective condensation, is subject to 3-dimensional advection and vertical diffusion. The cloud water enters the radiation calculations through the long wave emissivity calculations. Results from several sensitivity simulations show that realistic cloud water and precipitation fields can be obtained with the applied method. Comparisons with observations show that the most realistic results are obtained when more sophisticated schemes for moist convection are introduced at the same time. The model's cold bias is reduced and the zonal winds become stronger, due to more realistic tropical convection

  17. General Model for Light Curves of Chromospherically Active Binary Stars

    Science.gov (United States)

    Jetsu, L.; Henry, G. W.; Lehtinen, J.

    2017-04-01

    The starspots on the surface of many chromospherically active binary stars concentrate on long-lived active longitudes separated by 180°. Shifts in activity between these two longitudes, the “flip-flop” events, have been observed in single stars like FK Comae and binary stars like σ Geminorum. Recently, interferometry has revealed that ellipticity may at least partly explain the flip-flop events in σ Geminorum. This idea was supported by the double-peaked shape of the long-term mean light curve of this star. Here we show that the long-term mean light curves of 14 chromospherically active binaries follow a general model that explains the connection between orbital motion, changes in starspot distribution, ellipticity, and flip-flop events. Surface differential rotation is probably weak in these stars, because the interference of two constant period waves may explain the observed light curve changes. These two constant periods are the active longitude period ({P}{act}) and the orbital period ({P}{orb}). We also show how to apply the same model to single stars, where only the value of P act is known. Finally, we present a tentative interference hypothesis about the origin of magnetic fields in all spectral types of stars. The CPS results are available electronically at the Vizier database.

  18. A general method for modeling population dynamics and its applications.

    Science.gov (United States)

    Shestopaloff, Yuri K

    2013-12-01

    Studying populations, be it a microbe colony or mankind, is important for understanding how complex systems evolve and exist. Such knowledge also often provides insights into evolution, history and different aspects of human life. By and large, populations' prosperity and decline is about transformation of certain resources into quantity and other characteristics of populations through growth, replication, expansion and acquisition of resources. We introduce a general model of population change, applicable to different types of populations, which interconnects numerous factors influencing population dynamics, such as nutrient influx and nutrient consumption, reproduction period, reproduction rate, etc. It is also possible to take into account specific growth features of individual organisms. We considered two recently discovered distinct growth scenarios: first, when organisms do not change their grown mass regardless of nutrients availability, and the second when organisms can reduce their grown mass by several times in a nutritionally poor environment. We found that nutrient supply and reproduction period are two major factors influencing the shape of population growth curves. There is also a difference in population dynamics between these two groups. Organisms belonging to the second group are significantly more adaptive to reduction of nutrients and far more resistant to extinction. Also, such organisms have substantially more frequent and lesser in amplitude fluctuations of population quantity for the same periodic nutrient supply (compared to the first group). Proposed model allows adequately describing virtually any possible growth scenario, including complex ones with periodic and irregular nutrient supply and other changing parameters, which present approaches cannot do.

  19. Bayes estimation of the general hazard rate model

    International Nuclear Information System (INIS)

    Sarhan, A.

    1999-01-01

    In reliability theory and life testing models, the life time distributions are often specified by choosing a relevant hazard rate function. Here a general hazard rate function h(t)=a+bt c-1 , where c, a, b are constants greater than zero, is considered. The parameter c is assumed to be known. The Bayes estimators of (a,b) based on the data of type II/item-censored testing without replacement are obtained. A large simulation study using Monte Carlo Method is done to compare the performance of Bayes with regression estimators of (a,b). The criterion for comparison is made based on the Bayes risk associated with the respective estimator. Also, the influence of the number of failed items on the accuracy of the estimators (Bayes and regression) is investigated. Estimations for the parameters (a,b) of the linearly increasing hazard rate model h(t)=a+bt, where a, b are greater than zero, can be obtained as the special case, letting c=2

  20. Generalized Functional Linear Models With Semiparametric Single-Index Interactions

    KAUST Repository

    Li, Yehua

    2010-06-01

    We introduce a new class of functional generalized linear models, where the response is a scalar and some of the covariates are functional. We assume that the response depends on multiple covariates, a finite number of latent features in the functional predictor, and interaction between the two. To achieve parsimony, the interaction between the multiple covariates and the functional predictor is modeled semiparametrically with a single-index structure. We propose a two step estimation procedure based on local estimating equations, and investigate two situations: (a) when the basis functions are pre-determined, e.g., Fourier or wavelet basis functions and the functional features of interest are known; and (b) when the basis functions are data driven, such as with functional principal components. Asymptotic properties are developed. Notably, we show that when the functional features are data driven, the parameter estimates have an increased asymptotic variance, due to the estimation error of the basis functions. Our methods are illustrated with a simulation study and applied to an empirical data set, where a previously unknown interaction is detected. Technical proofs of our theoretical results are provided in the online supplemental materials.

  1. Critical rotation of general-relativistic polytropic models revisited

    Science.gov (United States)

    Geroyannis, V.; Karageorgopoulos, V.

    2013-09-01

    We develop a perturbation method for computing the critical rotational parameter as a function of the equatorial radius of a rigidly rotating polytropic model in the "post-Newtonia approximation" (PNA). We treat our models as "initial value problems" (IVP) of ordinary differential equations in the complex plane. The computations are carried out by the code dcrkf54.f95 (Geroyannis and Valvi 2012 [P1]; modified Runge-Kutta-Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane). Such a complex-plane treatment removes the syndromes appearing in this particular family of IVPs (see e.g. P1, Sec. 3) and allows continuation of the numerical integrations beyond the surface of the star. Thus all the required values of the Lane-Emden function(s) in the post-Newtonian approximation are calculated by interpolation (so avoiding any extrapolation). An interesting point is that, in our computations, we take into account the complete correction due to the gravitational term, and this issue is a remarkable difference compared to the classical PNA. We solve the generalized density as a function of the equatorial radius and find the critical rotational parameter. Our computations are extended to certain other physical characteristics (like mass, angular momentum, rotational kinetic energy, etc). We find that our method yields results comparable with those of other reliable methods. REFERENCE: V.S. Geroyannis and F.N. Valvi 2012, International Journal of Modern Physics C, 23, No 5, 1250038:1-15.

  2. Cognitive performance modeling based on general systems performance theory.

    Science.gov (United States)

    Kondraske, George V

    2010-01-01

    General Systems Performance Theory (GSPT) was initially motivated by problems associated with quantifying different aspects of human performance. It has proved to be invaluable for measurement development and understanding quantitative relationships between human subsystem capacities and performance in complex tasks. It is now desired to bring focus to the application of GSPT to modeling of cognitive system performance. Previous studies involving two complex tasks (i.e., driving and performing laparoscopic surgery) and incorporating measures that are clearly related to cognitive performance (information processing speed and short-term memory capacity) were revisited. A GSPT-derived method of task analysis and performance prediction termed Nonlinear Causal Resource Analysis (NCRA) was employed to determine the demand on basic cognitive performance resources required to support different levels of complex task performance. This approach is presented as a means to determine a cognitive workload profile and the subsequent computation of a single number measure of cognitive workload (CW). Computation of CW may be a viable alternative to measuring it. Various possible "more basic" performance resources that contribute to cognitive system performance are discussed. It is concluded from this preliminary exploration that a GSPT-based approach can contribute to defining cognitive performance models that are useful for both individual subjects and specific groups (e.g., military pilots).

  3. Prognostic cloud water in the Los Alamos general circulation model

    International Nuclear Information System (INIS)

    Kristjansson, J.E.; Kao, C.Y.J.

    1994-01-01

    Most of today's general circulation models (GCMs) have a greatly simplified treatment of condensation and clouds. Recent observational studies of the earth's radiation budget have suggested cloud-related feedback mechanisms to be of tremendous importance for the issue of global change. Thus, an urgent need for improvements in the treatment of clouds in GCMs has arisen, especially as the clouds relate to radiation. In this paper, we investigate the effects of introducing prognostic cloud water into the Los Alamos GCM. The cloud water field, produced by both stratiform and convective condensation, is subject to 3-dimensional advection and vertical diffusion. The cloud water enters the radiation calculations through the longwave emissivity calculations. Results from several sensitivity simulations show that realistic water and precipitation fields can be obtained with the applied method. Comparisons with observations show that the most realistic results are obtained when more sophisticated schemes for moist convection are introduced at the same time. The model's cold bias is reduced and the zonal winds becomes stronger because of more realistic tropical convection

  4. Care Model Design for E-Health: Integration of Point-of-Care Testing at Dutch General Practices

    Directory of Open Access Journals (Sweden)

    Bart Verhees

    2017-12-01

    Full Text Available Point-of-care testing (POCT—laboratory tests performed with new mobile devices and online technologies outside of the central laboratory—is rapidly outpacing the traditional laboratory test market, growing at a rate of 12 to 15% each year. POCT impacts the diagnostic process of care providers by yielding high efficiency benefits in terms of turnaround time and related quality improvements in the reduction of errors. However, the implementation of this disruptive eHealth technology requires the integration and transformation of diagnostic services across the boundaries of healthcare organizations. Research has revealed both advantages and barriers of POCT implementations, yet to date, there is no business model for the integration of POCT within general practice. The aim of this article is to contribute with a design for a care model that enables the integration of POCT in primary healthcare. In this research, we used a design modelling toolkit for data collection at five general practices. Through an iterative design process, we modelled the actors and value transactions, and designed an optimized care model for the dynamic integration of POCTs into the GP’s network of care delivery. The care model design will have a direct bearing on improving the integration of POCT through the connectivity and norm guidelines between the general practice, the POC technology, and the diagnostic centre.

  5. Care Model Design for E-Health: Integration of Point-of-Care Testing at Dutch General Practices.

    Science.gov (United States)

    Verhees, Bart; van Kuijk, Kees; Simonse, Lianne

    2017-12-21

    Point-of-care testing (POCT)-laboratory tests performed with new mobile devices and online technologies outside of the central laboratory-is rapidly outpacing the traditional laboratory test market, growing at a rate of 12 to 15% each year. POCT impacts the diagnostic process of care providers by yielding high efficiency benefits in terms of turnaround time and related quality improvements in the reduction of errors. However, the implementation of this disruptive eHealth technology requires the integration and transformation of diagnostic services across the boundaries of healthcare organizations. Research has revealed both advantages and barriers of POCT implementations, yet to date, there is no business model for the integration of POCT within general practice. The aim of this article is to contribute with a design for a care model that enables the integration of POCT in primary healthcare. In this research, we used a design modelling toolkit for data collection at five general practices. Through an iterative design process, we modelled the actors and value transactions, and designed an optimized care model for the dynamic integration of POCTs into the GP's network of care delivery. The care model design will have a direct bearing on improving the integration of POCT through the connectivity and norm guidelines between the general practice, the POC technology, and the diagnostic centre.

  6. Design and implementation of a generalized laboratory data model

    Directory of Open Access Journals (Sweden)

    Nhan Mike

    2007-09-01

    Full Text Available Abstract Background Investigators in the biological sciences continue to exploit laboratory automation methods and have dramatically increased the rates at which they can generate data. In many environments, the methods themselves also evolve in a rapid and fluid manner. These observations point to the importance of robust information management systems in the modern laboratory. Designing and implementing such systems is non-trivial and it appears that in many cases a database project ultimately proves unserviceable. Results We describe a general modeling framework for laboratory data and its implementation as an information management system. The model utilizes several abstraction techniques, focusing especially on the concepts of inheritance and meta-data. Traditional approaches commingle event-oriented data with regular entity data in ad hoc ways. Instead, we define distinct regular entity and event schemas, but fully integrate these via a standardized interface. The design allows straightforward definition of a "processing pipeline" as a sequence of events, obviating the need for separate workflow management systems. A layer above the event-oriented schema integrates events into a workflow by defining "processing directives", which act as automated project managers of items in the system. Directives can be added or modified in an almost trivial fashion, i.e., without the need for schema modification or re-certification of applications. Association between regular entities and events is managed via simple "many-to-many" relationships. We describe the programming interface, as well as techniques for handling input/output, process control, and state transitions. Conclusion The implementation described here has served as the Washington University Genome Sequencing Center's primary information system for several years. It handles all transactions underlying a throughput rate of about 9 million sequencing reactions of various kinds per month and

  7. Log-normal frailty models fitted as Poisson generalized linear mixed models.

    Science.gov (United States)

    Hirsch, Katharina; Wienke, Andreas; Kuss, Oliver

    2016-12-01

    The equivalence of a survival model with a piecewise constant baseline hazard function and a Poisson regression model has been known since decades. As shown in recent studies, this equivalence carries over to clustered survival data: A frailty model with a log-normal frailty term can be interpreted and estimated as a generalized linear mixed model with a binary response, a Poisson likelihood, and a specific offset. Proceeding this way, statistical theory and software for generalized linear mixed models are readily available for fitting frailty models. This gain in flexibility comes at the small price of (1) having to fix the number of pieces for the baseline hazard in advance and (2) having to "explode" the data set by the number of pieces. In this paper we extend the simulations of former studies by using a more realistic baseline hazard (Gompertz) and by comparing the model under consideration with competing models. Furthermore, the SAS macro %PCFrailty is introduced to apply the Poisson generalized linear mixed approach to frailty models. The simulations show good results for the shared frailty model. Our new %PCFrailty macro provides proper estimates, especially in case of 4 events per piece. The suggested Poisson generalized linear mixed approach for log-normal frailty models based on the %PCFrailty macro provides several advantages in the analysis of clustered survival data with respect to more flexible modelling of fixed and random effects, exact (in the sense of non-approximate) maximum likelihood estimation, and standard errors and different types of confidence intervals for all variance parameters. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Centering, Scale Indeterminacy, and Differential Item Functioning Detection in Hierarchical Generalized Linear and Generalized Linear Mixed Models

    Science.gov (United States)

    Cheong, Yuk Fai; Kamata, Akihito

    2013-01-01

    In this article, we discuss and illustrate two centering and anchoring options available in differential item functioning (DIF) detection studies based on the hierarchical generalized linear and generalized linear mixed modeling frameworks. We compared and contrasted the assumptions of the two options, and examined the properties of their DIF…

  9. Generalized equilibrium modeling: the methodology of the SRI-Gulf energy model. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gazalet, E.G.

    1977-05-01

    The report provides documentation of the generalized equilibrium modeling methodology underlying the SRI-Gulf Energy Model and focuses entirely on the philosophical, mathematical, and computational aspects of the methodology. The model is a highly detailed regional and dynamic model of the supply and demand for energy in the US. The introduction emphasized the need to focus modeling efforts on decisions and the coordinated decomposition of complex decision problems using iterative methods. The conceptual framework is followed by a description of the structure of the current SRI-Gulf model and a detailed development of the process relations that comprise the model. The network iteration algorithm used to compute a solution to the model is described and the overall methodology is compared with other modeling methodologies. 26 references.

  10. Maximum Likelihood in a Generalized Linear Finite Mixture Model by Using the EM Algorithm

    NARCIS (Netherlands)

    Jansen, R.C.

    A generalized linear finite mixture model and an EM algorithm to fit the model to data are described. By this approach the finite mixture model is embedded within the general framework of generalized linear models (GLMs). Implementation of the proposed EM algorithm can be readily done in statistical

  11. Explicit prediction of ice clouds in general circulation models

    Science.gov (United States)

    Kohler, Martin

    1999-11-01

    Although clouds play extremely important roles in the radiation budget and hydrological cycle of the Earth, there are large quantitative uncertainties in our understanding of their generation, maintenance and decay mechanisms, representing major obstacles in the development of reliable prognostic cloud water schemes for General Circulation Models (GCMs). Recognizing their relative neglect in the past, both observationally and theoretically, this work places special focus on ice clouds. A recent version of the UCLA - University of Utah Cloud Resolving Model (CRM) that includes interactive radiation is used to perform idealized experiments to study ice cloud maintenance and decay mechanisms under various conditions in term of: (1) background static stability, (2) background relative humidity, (3) rate of cloud ice addition over a fixed initial time-period and (4) radiation: daytime, nighttime and no-radiation. Radiation is found to have major effects on the life-time of layer-clouds. Optically thick ice clouds decay significantly slower than expected from pure microphysical crystal fall-out (taucld = 0.9--1.4 h as opposed to no-motion taumicro = 0.5--0.7 h). This is explained by the upward turbulent fluxes of water induced by IR destabilization, which partially balance the downward transport of water by snowfall. Solar radiation further slows the ice-water decay by destruction of the inversion above cloud-top and the resulting upward transport of water. Optically thin ice clouds, on the other hand, may exhibit even longer life-times (>1 day) in the presence of radiational cooling. The resulting saturation mixing ratio reduction provides for a constant cloud ice source. These CRM results are used to develop a prognostic cloud water scheme for the UCLA-GCM. The framework is based on the bulk water phase model of Ose (1993). The model predicts cloud liquid water and cloud ice separately, and which is extended to split the ice phase into suspended cloud ice (predicted

  12. Multi-year predictability in a coupled general circulation model

    Energy Technology Data Exchange (ETDEWEB)

    Power, Scott; Colman, Rob [Bureau of Meteorology Research Centre, Melbourne, VIC (Australia)

    2006-02-01

    Multi-year to decadal variability in a 100-year integration of a BMRC coupled atmosphere-ocean general circulation model (CGCM) is examined. The fractional contribution made by the decadal component generally increases with depth and latitude away from surface waters in the equatorial Indo-Pacific Ocean. The relative importance of decadal variability is enhanced in off-equatorial ''wings'' in the subtropical eastern Pacific. The model and observations exhibit ''ENSO-like'' decadal patterns. Analytic results are derived, which show that the patterns can, in theory, occur in the absence of any predictability beyond ENSO time-scales. In practice, however, modification to this stochastic view is needed to account for robust differences between ENSO-like decadal patterns and their interannual counterparts. An analysis of variability in the CGCM, a wind-forced shallow water model, and a simple mixed layer model together with existing and new theoretical results are used to improve upon this stochastic paradigm and to provide a new theory for the origin of decadal ENSO-like patterns like the Interdecadal Pacific Oscillation and Pacific Decadal Oscillation. In this theory, ENSO-driven wind-stress variability forces internal equatorially-trapped Kelvin waves that propagate towards the eastern boundary. Kelvin waves can excite reflected internal westward propagating equatorially-trapped Rossby waves (RWs) and coastally-trapped waves (CTWs). CTWs have no impact on the off-equatorial sub-surface ocean outside the coastal wave guide, whereas the RWs do. If the frequency of the incident wave is too high, then only CTWs are excited. At lower frequencies, both CTWs and RWs can be excited. The lower the frequency, the greater the fraction of energy transmitted to RWs. This lowers the characteristic frequency of variability off the equator relative to its equatorial counterpart. Both the eastern boundary interactions and the accumulation of

  13. R(D(*)) in a general two Higgs doublet model

    Science.gov (United States)

    Iguro, Syuhei; Tobe, Kazuhiro

    2017-12-01

    Motivated by an anomaly in R (D (*)) = BR (B bar →D (*)τ- ν bar) / BR (B bar →D (*)l- ν bar) reported by BaBar, Belle and LHCb, we study R (D (*)) in a general two Higgs doublet model (2HDM). Although it has been suggested that it is difficult for the 2HDM to explain the current world average for R (D (*)), it would be important to clarify how large deviations from the standard model predictions for R (D (*)) are possible in the 2HDM. We investigate possible corrections to R (D (*)) in the 2HDM by taking into account various flavor physics constraints (such as Bc- →τ- ν bar , b → sγ, b → sl+l-, Δm Bd,s, Bs →μ+μ- and τ+τ-, and B- →τ- ν bar), and find that it would be possible (impossible) to accommodate the 1σ region suggested by the Belle's result when we adopt a constraint BR (Bc- →τ- ν bar) ≤ 30% (BR (Bc- →τ- ν bar) ≤ 10%). We also study productions and decays of heavy neutral and charged Higgs bosons at the Large Hadron Collider (LHC) experiment and discuss the constraints and implications at the LHC. We show that in addition to well-studied production modes bg → tH- and gg → H / A, exotic productions of heavy Higgs bosons such as cg → bH+ , t + H / A and c b bar →H+ would be significantly large, and the search for their exotic decay modes such as H / A → t c bar + c t bar , μ±τ∓ and H+ → c b bar as well as H / A →τ+τ- and H+ →τ+ ν would be important to probe the interesting parameter regions for R (D (*)).

  14. Proton radioactivity within a generalized liquid drop model

    Science.gov (United States)

    Dong, J. M.; Zhang, H. F.; Royer, G.

    2009-05-01

    The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of protons are determined in the quasimolecular shape path within a generalized liquid drop model (GLDM) including the proximity effects between nuclei in a neck and the mass and charge asymmetry. The penetrability is calculated with the WKB approximation. The spectroscopic factor has been taken into account in half-life calculation, which is obtained by employing the relativistic mean field (RMF) theory combined with the BCS method with the force NL3. The half-lives within the GLDM are compared with the experimental data and other theoretical values. The GLDM works quite well for spherical proton emitters when the spectroscopic factors are considered, indicating the necessity of introducing the spectroscopic factor and the success of the GLDM for proton emission. Finally, we present two formulas for proton emission half-life calculation similar to the Viola-Seaborg formulas and Royer's formulas of α decay.

  15. The Extended Generalized Cost Concept and its Application in Freight Transport and General Equilibrium Modeling

    NARCIS (Netherlands)

    Tavasszy, L.; Davydenko, I.; Ruijgrok, K.

    2009-01-01

    The integration of Spatial Equilibrium models and Freight transport network models is important to produce consistent scenarios for future freight transport demand. At various spatial scales, we see the changes in production, trade, logistics networking and transportation, being driven by

  16. An update of comprehensive evidence-based guidelines for interventional techniques in chronic spinal pain. Part I: introduction and general considerations.

    Science.gov (United States)

    Manchikanti, Laxmaiah; Falco, Frank J E; Singh, Vijay; Benyamin, Ramsin M; Racz, Gabor B; Helm, Standiford; Caraway, David L; Calodney, Aaron K; Snook, Lee T; Smith, Howard S; Gupta, Sanjeeva; Ward, Stephen P; Grider, Jay S; Hirsch, Joshua A

    2013-04-01

    In 2011, the Institute of Medicine (IOM) re-engineered its definition of clinical guidelines as follows: "clinical practice guidelines are statements that include recommendations intended to optimize patient care that are informed by a systematic review of evidence and an assessment of the benefit and harms of alternative care options." This new definition departs from a 2-decade old definition from a 1990 IOM report that defined guidelines as "systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances." The revised definition clearly distinguishes between the term "clinical practice guideline" and other forms of clinical guidance derived from widely disparate development processes, such as consensus statements, expert advice, and appropriate use criteria. The IOM committee acknowledged that for many clinical domains, high quality evidence was lacking or even nonexistent. Even though the guidelines are important decision-making tools, along with expert clinical judgment and patient preference, their value and impact remains variable due to numerous factors. Some of the many factors that impede the development of clinical practice guidelines include bias due to a variety of conflicts of interest, inappropriate and poor methodological quality, poor writing and ambiguous presentation, projecting a view that these are not applicable to individual patients or too restrictive with elimination of clinician autonomy, and overzealous and inappropriate recommendations, either positive, negative, or non-committal. Consequently, a knowledgeable, multidisciplinary panel of experts must develop guidelines based on a systematic review of the existing evidence, as recently recommended by the IOM. Chronic pain is a complex and multifactorial phenomenon associated with significant economic, social, and health outcomes. Interventional pain management is an emerging specialty facing a

  17. Strategies for the introduction and implementation of a guideline for the treatment of type 2 diabetics by general practitioners (GPs of the Lazio region of Italy (IMPLEMEG study: Protocol for a cluster randomised controlled trial [ISRCTN80116232

    Directory of Open Access Journals (Sweden)

    Perria Carla

    2004-06-01

    Full Text Available Abstract Background Despite broad agreement on the necessity to improve quality of diabetic care through implementation of clinical guidelines, in Italy many people with diabetes still lack adequate care in general practice. In addition there is little evidence to support the choice of implementation strategies, especially in the Lazio region (central Italy, where comparative studies among general practitioners (GPs are uncommon. The primary objective of the study is to assess the effectiveness of different strategies for the implementation of an evidence-based guideline for the management of non-complicated type 2 diabetes mellitus (DM among GPs of the Lazio region. Methods/Design Three-arm cluster-randomised trial (C-RCT. 252 GPs were randomised either to arm 1 (comprising a training module and administration of the guideline, or to arm 2 (administration of guideline without training, or to arm 3 (control arm, continuing current practice. Arm 1 participants attended a two-day course with CME credits. Data collection will be performed using current information systems. Patients' health data was also collected to describe diabetic populations cared for by GP participants. Process outcomes will be measured at the patient level and at the cluster level one year after the intervention. We will assess GPs' adherence to guideline recommendations for diabetes management relative to: 1 pharmacological management of diabetes; 2 pharmacological management of cardiovascular risk factors (hypertension and dislypidaemia; 3 measurement of glycosilated haemoglobin as the principal indicator of glycaemic control; 4 micro- and macrovascular complications assessment tests. Outcomes will be expressed as proportions of patients cared for by GPs who will have prescriptions of drugs, requests for tests and for outpatient appointment visits. To estimate the efficiency of resource use associated with the intervention a cost-effectiveness analysis will be carried out

  18. Economic Evaluation of Active Implementation versus Guideline Dissemination for Evidence-Based Care of Acute Low-Back Pain in a General Practice Setting

    Science.gov (United States)

    Mortimer, Duncan; French, Simon D.; McKenzie, Joanne E.; O′Connor, Denise A.; Green, Sally E.

    2013-01-01

    Introduction The development and publication of clinical practice guidelines for acute low-back pain has resulted in evidence-based recommendations that have the potential to improve the quality and safety of care for acute low-back pain. Development and dissemination of guidelines may not, however, be sufficient to produce improvements in clinical practice; further investment in active implementation of guideline recommendations may be required. Further research is required to quantify the trade-off between the additional upfront cost of active implementation of guideline recommendations for low-back pain and any resulting improvements in clinical practice. Methods Cost-effectiveness analysis alongside the IMPLEMENT trial from a health sector perspective to compare active implementation of guideline recommendations via the IMPLEMENT intervention (plus standard dissemination) against standard dissemination alone. Results The base-case analysis suggests that delivery of the IMPLEMENT intervention dominates standard dissemination (less costly and more effective), yielding savings of $135 per x-ray referral avoided (-$462.93/3.43). However, confidence intervals around point estimates for the primary outcome suggest that – irrespective of willingness to pay (WTP) – we cannot be at least 95% confident that the IMPLEMENT intervention differs in value from standard dissemination. Conclusions Our findings demonstrate that moving beyond development and dissemination to active implementation entails a significant additional upfront investment that may not be offset by health gains and/or reductions in health service utilization of sufficient magnitude to render active implementation cost-effective. PMID:24146767

  19. The DSM-5 dimensional trait model and five-factor models of general personality.

    Science.gov (United States)

    Gore, Whitney L; Widiger, Thomas A

    2013-08-01

    The current study tests empirically the relationship of the dimensional trait model proposed for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) with five-factor models of general personality. The DSM-5 maladaptive trait dimensional model proposal included 25 traits organized within five broad domains (i.e., negative affectivity, detachment, antagonism, disinhibition, and psychoticism). Consistent with the authors of the proposal, it was predicted that negative affectivity would align with five-factor model (FFM) neuroticism, detachment with FFM introversion, antagonism with FFM antagonism, disinhibition with low FFM conscientiousness and, contrary to the proposal; psychoticism would align with FFM openness. Three measures of alternative five-factor models of general personality were administered to 445 undergraduates along with the Personality Inventory for DSM-5. The results provided support for the hypothesis that all five domains of the DSM-5 dimensional trait model are maladaptive variants of general personality structure, including the domain of psychoticism. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  20. Generalized Network Psychometrics : Combining Network and Latent Variable Models

    NARCIS (Netherlands)

    Epskamp, S.; Rhemtulla, M.; Borsboom, D.

    2017-01-01

    We introduce the network model as a formal psychometric model, conceptualizing the covariance between psychometric indicators as resulting from pairwise interactions between observable variables in a network structure. This contrasts with standard psychometric models, in which the covariance between

  1. Generalized versus non-generalized neural network model for multi-lead inflow forecasting at Aswan High Dam

    Directory of Open Access Journals (Sweden)

    A. El-Shafie

    2011-03-01

    Full Text Available Artificial neural networks (ANN have been found efficient, particularly in problems where characteristics of the processes are stochastic and difficult to describe using explicit mathematical models. However, time series prediction based on ANN algorithms is fundamentally difficult and faces problems. One of the major shortcomings is the search for the optimal input pattern in order to enhance the forecasting capabilities for the output. The second challenge is the over-fitting problem during the training procedure and this occurs when ANN loses its generalization. In this research, autocorrelation and cross correlation analyses are suggested as a method for searching the optimal input pattern. On the other hand, two generalized methods namely, Regularized Neural Network (RNN and Ensemble Neural Network (ENN models are developed to overcome the drawbacks of classical ANN models. Using Generalized Neural Network (GNN helped avoid over-fitting of training data which was observed as a limitation of classical ANN models. Real inflow data collected over the last 130 years at Lake Nasser was used to train, test and validate the proposed model. Results show that the proposed GNN model outperforms non-generalized neural network and conventional auto-regressive models and it could provide accurate inflow forecasting.

  2. Global Imaging referral guidelines

    International Nuclear Information System (INIS)

    Kawooya, M.; Perez, M.; Lau, L.; Reeed, M.

    2010-01-01

    The medical imaging specialists called for global referral guidelines which would be made available to referring doctors. These referral guidelines should be:- Applicable in different health care settings, including resource-poor settings; Inclusive in terms of the range of clinical conditions; User-friendly and accessible (format/media); Acceptable to stakeholders, in particular to the referrers as the main target audience. To conceive evidence-based medicine as an integration of best research evidence with clinical expertise and patient values. The Direct recipients of the Referral Guidelines would be:- Referrers: general practitioners / family doctors; paediatricians; emergency department doctors; other specialists and health workers. Providers (medical imaging practitioners): radiologists; nuclear medicine physicians; radiographers; other appropriately qualified practitioners providing diagnostic imaging services. For the Referral Guidelines to be effective there need to be: Credibility evidence-based Practicality end user involvement Context local resources, disease profiles Endorsement, opinion leaders Implementation- policy, education, CPOE - Monitoring of the use clinical audit, report feedback. The aim of the Referral Guidelines Project was to: Produce global referral guidelines that are evidence-based, cost effective and appropriate for the local setting, and include consideration of available equipment and expertise (RGWG; SIGs); Include supporting information about radiation doses, potential risks, protection of children and pregnant women (introductory chapter); Facilitate the implementation of the guidelines through guidance and tools (e.g. implementation guides, checklists, capacity building tools, guides on stakeholders engagement, audit support criteria); Conduct pilot testing in different clinical settings from each of the six WHO regions; Promote the inclusion of the referral guidelines in the curricula of medical schools; Develop and implement

  3. Generalized Degrees of Freedom and Adaptive Model Selection in Linear Mixed-Effects Models.

    Science.gov (United States)

    Zhang, Bo; Shen, Xiaotong; Mumford, Sunni L

    2012-03-01

    Linear mixed-effects models involve fixed effects, random effects and covariance structure, which require model selection to simplify a model and to enhance its interpretability and predictability. In this article, we develop, in the context of linear mixed-effects models, the generalized degrees of freedom and an adaptive model selection procedure defined by a data-driven model complexity penalty. Numerically, the procedure performs well against its competitors not only in selecting fixed effects but in selecting random effects and covariance structure as well. Theoretically, asymptotic optimality of the proposed methodology is established over a class of information criteria. The proposed methodology is applied to the BioCycle study, to determine predictors of hormone levels among premenopausal women and to assess variation in hormone levels both between and within women across the menstrual cycle.

  4. Hydraulic fracturing model based on the discrete fracture model and the generalized J integral

    Science.gov (United States)

    Liu, Z. Q.; Liu, Z. F.; Wang, X. H.; Zeng, B.

    2016-08-01

    The hydraulic fracturing technique is an effective stimulation for low permeability reservoirs. In fracturing models, one key point is to accurately calculate the flux across the fracture surface and the stress intensity factor. To achieve high precision, the discrete fracture model is recommended to calculate the flux. Using the generalized J integral, the present work obtains an accurate simulation of the stress intensity factor. Based on the above factors, an alternative hydraulic fracturing model is presented. Examples are included to demonstrate the reliability of the proposed model and its ability to model the fracture propagation. Subsequently, the model is used to describe the relationship between the geometry of the fracture and the fracturing equipment parameters. The numerical results indicate that the working pressure and the pump power will significantly influence the fracturing process.

  5. [Guidelines for the management of dyslipidemia].

    Science.gov (United States)

    Díaz Rodríguez, Ángel

    2014-09-01

    The AHA/ACC 2013 guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular disease (ASCVD) in adults contains major differences with the previous ESC/EAS 2011 guidelines and the remaining international guidelines, which has generated major controversies. The AHA/ACC document has developed a new model for estimating cardiovascular risk for primary prevention which is not comparable with the SCORE recommended in the European guidelines. This guideline does not establish a fixed target for low-density lipoprotein cholesterol (LDLc). Instead, it identifies 4 major statin benefit groups at risk for the development ASCVD, who should receive low-, moderate-, and high-intensity statin therapy to reduce LCLc. In contrast, the European guidelines maintain LDLc as the main treatment target and non-high-density lipoprotein cholesterol as a secondary treatment target. The document recommends calculating cardiovascular risk for the overall treatment of patients with dyslipidemia according to 4 risk levels (low, moderate, high, and very high), establishes LDLc treatment targets, and recommends a statin-based therapeutic strategy and other, lipid-lowering strategies, aimed at achieving these targets. The American guidelines cannot be extrapolated to the European population. Target-based treatment, as recommended in the EAS/ESC guidelines, is the best strategy for Europe. In Spain, the Primary Care Guidelines of the Spanish Society of Family and Community Medicine (semFYC) and the Spanish Society of Primary Care Physicians (SEMERGEN) are based on the European recommendations. Finally, the Spanish Society of Arteriosclerosis (SEA), SEMERGEN, semFYC and the Spanish Society of General Medicine (SEMG) are reaching a consensus on the approach and management of patients with atherogenic dyslipidemia in primary care. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Medicina Rural y Generalista (SEMERGEN). All rights reserved.

  6. Optimal Scaling of Interaction Effects in Generalized Linear Models

    Science.gov (United States)

    van Rosmalen, Joost; Koning, Alex J.; Groenen, Patrick J. F.

    2009-01-01

    Multiplicative interaction models, such as Goodman's (1981) RC(M) association models, can be a useful tool for analyzing the content of interaction effects. However, most models for interaction effects are suitable only for data sets with two or three predictor variables. Here, we discuss an optimal scaling model for analyzing the content of…

  7. Model-Based Methods for Fault Diagnosis: Some Guide-Lines

    DEFF Research Database (Denmark)

    Patton, R.J.; Chen, J.; Nielsen, S.B.

    1995-01-01

    This paper provides a review of model-based fault diagnosis techniques. Starting from basic principles, the properties.......This paper provides a review of model-based fault diagnosis techniques. Starting from basic principles, the properties....

  8. Modelling and simulation of human factors in aviation : Methods and guidelines

    NARCIS (Netherlands)

    Diggelen, J. van; Janssen, J.; Mioch, T.

    2011-01-01

    Modeling and Simulation (M&S) is the use of (computer-) simulated models to develop data as a basis for making managerial or technical decisions. Applications of M&S are wide spread, ranging from system simulation in early design stages, atmosphere modeling for weather forecasting, graphical

  9. Ultra-wideband miniaturized microstrip patch antennas for wireless communications: Design guidelines and modeling

    Science.gov (United States)

    Dandu, Varun Kumar

    The number of wireless communication applications continue to increase steadily, leading to competition for currently allocated frequency bands. Capacity issues in form of data rate and latency have always been a bottleneck for broadband wireless-communication usage. New communication systems like ultra-wideband (UWB) require larger bandwidth than what is normally utilized with traditional antenna techniques. The interest for compact consumer electronics is growing in the meantime, creating a demand on efficient and low profile antennas which can be integrated on a printed circuit board. The main objective of this thesis is to study, design, analyze and implement UWB low profile microstrip patch antenna that satisfy UWB technology requirements. Some methods to extend the bandwidth and other antenna parameters associated with wideband usages are studied. Several techniques are used for optimal UWB bandwidth performance of the UWB microstrip patch antenna. The performance parameters such as VSWR, Gain and radiation pattern of the UWB microstrip patch antenna is extensively investigated with simulations using FEKO. A set of simple design guidelines is proposed to provide approximate rules that result in optimum "first-pass" designs of probe-fed, miniaturized, low profile, microstrip UWB antennas using different bandwidth-enhancement techniques to satisfy UWB bandwidth that require minimal tuning.

  10. Guidelines for the Establishment of a Model Neighborhood Electric Vehicle (NEV) Fleet

    Energy Technology Data Exchange (ETDEWEB)

    Roberta Brayer; Donald Karner; Kevin Morrow; James Francfort

    2006-06-01

    The U.S. Department of Energy’s Advanced Vehicle Testing Activity tests neighborhood electric vehicles (NEVs) in both track and fleet testing environments. NEVs, which are also known as low speed vehicles, are light-duty vehicles with top speeds of between 20 and 25 mph, and total gross vehicle weights of approximately 2,000 pounds or less. NEVs have been found to be very viable alternatives to internal combustion engine vehicles based on their low operating costs. However, special charging infrastructure is usually necessary for successful NEV fleet deployment. Maintenance requirements are also unique to NEVs, especially if flooded lead acid batteries are used as they have watering requirements that require training, personnel protection equipment, and adherence to maintenance schedules. This report provides guidelines for fleet managers to follow in order to successfully introduce and operate NEVs in fleet environments. This report is based on the NEV testing and operational experience of personnel from the Advanced Vehicle Testing Activity, Electric Transportation Applications, and the Idaho National Laboratory.

  11. Hierarchical shrinkage priors and model fitting for high-dimensional generalized linear models.

    Science.gov (United States)

    Yi, Nengjun; Ma, Shuangge

    2012-11-26

    Abstract Genetic and other scientific studies routinely generate very many predictor variables, which can be naturally grouped, with predictors in the same groups being highly correlated. It is desirable to incorporate the hierarchical structure of the predictor variables into generalized linear models for simultaneous variable selection and coefficient estimation. We propose two prior distributions: hierarchical Cauchy and double-exponential distributions, on coefficients in generalized linear models. The hierarchical priors include both variable-specific and group-specific tuning parameters, thereby not only adopting different shrinkage for different coefficients and different groups but also providing a way to pool the information within groups. We fit generalized linear models with the proposed hierarchical priors by incorporating flexible expectation-maximization (EM) algorithms into the standard iteratively weighted least squares as implemented in the general statistical package R. The methods are illustrated with data from an experiment to identify genetic polymorphisms for survival of mice following infection with Listeria monocytogenes. The performance of the proposed procedures is further assessed via simulation studies. The methods are implemented in a freely available R package BhGLM (http://www.ssg.uab.edu/bhglm/).

  12. Drogodependencias en el lugar de trabajo: Pautas generales de intervención desde la medicina del trabajo Illicit drugs in the Workplace: General guidelines of intervention from the Occupational Health

    Directory of Open Access Journals (Sweden)

    Carmen Otero Dorrego

    2011-01-01

    último, facilitará la rehabilitación laboral (Prevención Terciaria favoreciendo la reincorporación laboral del trabajador con garantías de seguridad.Drug abuse is an important problem of public health, as well as a serious labor problem in industrialized countries. The serious labor consequences (smaller yield, increase of the number of accidents, etc. and the possibility of successfully approaching the problem from Occupational Health Services of companies, make the creation of politics and programs of intervention necessary. The overall goal of all these programs is to obtain the personal and labor rehabilitation of the affected workers. Other secondary targets are to improve the indices of absenteeism and accidentability, to establish general guidelines of performance of occupational health doctors to take part in the situations of drug abuse in the work place, as well as to favor the suitable labor restoration of workers who have followed a therapy program. In this article we make a revision of epidemiologic data, labor, personal and social consequences, different norms and international and national recommendations, as well as of specific programs of national and foreign companies in the different sectors from production. Finally, the general guidelines of intervention from Occupational Health Physicians are described. The performances of Occupational Health Physicians in the scope of Primary Prevention will be directed towards the detection of risk factors at work (evaluation of psycho-social risks and facility of access to drugs at work, among others and individual factors (early detection of specially sensible workers, applying correction measures (training courses, job adaptations, etc. Occupational Health Physicians will also make early diagnosis (Secondary Prevention for detox through the National Health System. Finally, they will facilitate labor rehabilitation (Tertiary Prevention favoring labor restoration of the worker with security guarantees.

  13. A general lexicographic model for a typological variety of ...

    African Journals Online (AJOL)

    eXtensible Markup Language/Web Ontology Language) representation model. This article follows another route in describing a model based on entities and relations between them; MySQL (usually referred to as: Structured Query Language) ...

  14. A generalized exponential time series regression model for electricity prices

    DEFF Research Database (Denmark)

    Haldrup, Niels; Knapik, Oskar; Proietti, Tomasso

    on the estimated model, the best linear predictor is constructed. Our modeling approach provides good fit within sample and outperforms competing benchmark predictors in terms of forecasting accuracy. We also find that building separate models for each hour of the day and averaging the forecasts is a better...

  15. Developing a Dynamic Stochastic General Equilibrium Model for the ...

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

    A range of applied economic tools, such as time series models or econometric models that build on simple statistical properties, have been used to provide these types of analyses. However, there is now an increasing body of economic literature that attempts to build economic models based on a more comprehensive and ...

  16. Poisson-generalized gamma empirical Bayes model for disease ...

    African Journals Online (AJOL)

    In spatial disease mapping, the use of Bayesian models of estimation technique is becoming popular for smoothing relative risks estimates for disease mapping. The most common Bayesian conjugate model for disease mapping is the Poisson-Gamma Model (PG). To explore further the activity of smoothing of relative risk ...

  17. Exact solution of generalized Schulz-Shastry type models

    International Nuclear Information System (INIS)

    Osterloh, Andreas; Amico, Luigi; Eckern, Ulrich

    2000-01-01

    A class of integrable one-dimensional models presented by Shastry and Schulz is consequently extended to the whole class of one-dimensional Hubbard- or XXZ-type models with correlated gauge-like hopping. A complete characterization concerning solvability by coordinate Bethe ansatz of this class of models is found

  18. Optimal Scaling of Interaction Effects in Generalized Linear Models

    NARCIS (Netherlands)

    J.M. van Rosmalen (Joost); A.J. Koning (Alex); P.J.F. Groenen (Patrick)

    2007-01-01

    textabstractMultiplicative interaction models, such as Goodman's RC(M) association models, can be a useful tool for analyzing the content of interaction effects. However, most models for interaction effects are only suitable for data sets with two or three predictor variables. Here, we discuss an

  19. Quantum mechanics vs. general covariance in gravity and string models

    International Nuclear Information System (INIS)

    Martinec, E.J.

    1984-01-01

    Quantization of simple low-dimensional systems embodying general covariance is studied. Functional methods are employed in the calculation of effective actions for fermionic strings and 1 + 1 dimensional gravity. The author finds that regularization breaks apparent symmetries of the theory, providing new dynamics for the string and non-trivial dynamics for 1 + 1 gravity. The author moves on to consider the quantization of some generally covariant systems with a finite number of physical degrees of freedom, assuming the existence of an invariant cutoff. The author finds that the wavefunction of the universe in these cases is given by the solution to simple quantum mechanics problems

  20. Generalized Heteroskedasticity ACF for Moving Average Models in Explicit Forms

    OpenAIRE

    Samir Khaled Safi

    2014-01-01

    The autocorrelation function (ACF) measures the correlation between observations at different   distances apart. We derive explicit equations for generalized heteroskedasticity ACF for moving average of order q, MA(q). We consider two cases: Firstly: when the disturbance term follow the general covariance matrix structure Cov(wi, wj)=S with si,j ¹ 0 " i¹j . Secondly: when the diagonal elements of S are not all identical but sij = 0 " i¹j, i.e. S=diag(s11, s22,&hellip...

  1. OSART guidelines

    International Nuclear Information System (INIS)

    1988-02-01

    The IAEA Operational Safety Review Team (OSART) programme provides advice and assistance to Member States to enhance the operational safety of nuclear power plants. These OSART Guidelines provide overall guidance for the experts to ensure the consistency and comprehensiveness of the operational safety review. Specific guidelines are provided as guide for the systematic review in the following areas important to operational safety: management, organization and administration, training and qualification, operations, maintenance, technical support, radiation protection, chemistry, emergency planning and preparedness

  2. Generalized isothermal models with strange equation of state

    Indian Academy of Sciences (India)

    Sri Lanka. *Corresponding author. E-mail: maharaj@ukzn.ac.za. MS received 30 October 2008; revised 5 December 2008; accepted 16 December 2008. Abstract. We consider the linear equation of state for matter distributions that may be applied to strange stars with quark matter. In our general approach the compact.

  3. Model-free adaptive sliding mode controller design for generalized ...

    Indian Academy of Sciences (India)

    To solve the difficulties from the little knowledge about the master–slave system and to overcome the bad effects of the external disturbances on the generalized projective synchronization, the radial basis function neural networks are used to approach the packaged unknown master system and the packaged unknown ...

  4. Nutrition counselling in general practice: the stages of change model

    NARCIS (Netherlands)

    Verheijden, M.W.

    2004-01-01

    Healthy lifestyles in the prevention of cardiovascular diseases are of utmost importance for people with non insulin-dependent diabetes mellitus, hypertension, and/or dyslipidemia. Because of their continuous contact with almost all segments of the population, general practitioners can play an

  5. Bianchi type IX string cosmological model in general relativity

    Indian Academy of Sciences (India)

    Cosmic strings arise during phase transitions after the big-bang explosion as the temperature goes down below some critical temperature [1–3]. These strings have stress energy and couple in a simple way to the gravitational field. The general relativistic formalism of cosmic strings is due to Letelier [4,5]. Stachel [6] has ...

  6. Setting Generality of Peer Modeling in Children with Autism.

    Science.gov (United States)

    Carr, Edward G.; Darcy, Michael

    1990-01-01

    Four preschool children with autism played "Follow-the-Leader," in which a normal peer demonstrated and physically prompted a variety of actions and object manipulations that defined the activity. Following training, all four subjects generalized their imitative skill to a new setting involving new actions and object manipulations. (Author/JDD)

  7. General model and control of an n rotor helicopter

    International Nuclear Information System (INIS)

    Sidea, A G; Brogaard, R Yding; Andersen, N A; Ravn, O

    2014-01-01

    The purpose of this study was to create a dynamic, nonlinear mathematical model of a multirotor that would be valid for different numbers of rotors. Furthermore, a set of Single Input Single Output (SISO) controllers were implemented for attitude control. Both model and controllers were tested experimentally on a quadcopter. Using the combined model and controllers, simple system simulation and control is possible, by replacing the physical values for the individual systems

  8. General model and control of an n rotor helicopter

    Science.gov (United States)

    Sidea, A. G.; Yding Brogaard, R.; Andersen, N. A.; Ravn, O.

    2014-12-01

    The purpose of this study was to create a dynamic, nonlinear mathematical model of a multirotor that would be valid for different numbers of rotors. Furthermore, a set of Single Input Single Output (SISO) controllers were implemented for attitude control. Both model and controllers were tested experimentally on a quadcopter. Using the combined model and controllers, simple system simulation and control is possible, by replacing the physical values for the individual systems.

  9. Generalized linear longitudinal mixed models with linear covariance structure and multiplicative random effects

    DEFF Research Database (Denmark)

    Holst, René; Jørgensen, Bent

    2015-01-01

    The paper proposes a versatile class of multiplicative generalized linear longitudinal mixed models (GLLMM) with additive dispersion components, based on explicit modelling of the covariance structure. The class incorporates a longitudinal structure into the random effects models and retains...

  10. Measuring and Examining General Self-Efficacy among Community College Students: A Structural Equation Modeling Approach

    Science.gov (United States)

    Chen, Yu; Starobin, Soko S.

    2018-01-01

    This study examined a psychosocial mechanism of how general self-efficacy interacts with other key factors and influences degree aspiration for students enrolled in an urban diverse community college. Using general self-efficacy scales, the authors hypothesized the General Self-efficacy model for Community College students (the GSE-CC model). A…

  11. Phase transitions in self-dual generalizations of the Baxter-Wu model

    NARCIS (Netherlands)

    Deng, Y.; Guo, W.; Heringa, J.R.; Blöte, H.W.J.; Nienhuis, B.

    2010-01-01

    We study two types of generalized Baxter-Wu models, by means of transfer-matrix and Monte Carlo techniques. The first generalization allows for different couplings in the up- and down-triangles, and the second generalization is to a q-state spin model with three-spin interactions. Both

  12. Modelo de Alfabetizacion: A Poblacion Urbana y Rural. Documento General (Literacy Model: Urban and Rural Populations. General Document).

    Science.gov (United States)

    Instituto Nacional para la Educacion de los Adultos, Mexico City (Mexico).

    This document describes literacy models for urban and rural populations in Mexico. It contains four sections. The first two sections (generalizations about the population and considerations about the teaching of adults) discuss the environment that creates illiterate adults and also describe some of the conditions under which learning takes place…

  13. Generalized height-diameter models for Populus tremula L. stands

    African Journals Online (AJOL)

    USER

    2010-07-12

    Jul 12, 2010 ... Using permanent sample plot data, selected tree height and diameter functions were evaluated for their predictive abilities for Populus tremula stands in Turkey. Two sets of models were evaluated. The first set included five models for estimating height as a function of individual tree diameter; the second set.

  14. General Dynamic Equivalent Modeling of Microgrid Based on Physical Background

    Directory of Open Access Journals (Sweden)

    Changchun Cai

    2015-11-01

    Full Text Available Microgrid is a new power system concept consisting of small-scale distributed energy resources; storage devices and loads. It is necessary to employ a simplified model of microgrid in the simulation of a distribution network integrating large-scale microgrids. Based on the detailed model of the components, an equivalent model of microgrid is proposed in this paper. The equivalent model comprises two parts: namely, equivalent machine component and equivalent static component. Equivalent machine component describes the dynamics of synchronous generator, asynchronous wind turbine and induction motor, equivalent static component describes the dynamics of photovoltaic, storage and static load. The trajectory sensitivities of the equivalent model parameters with respect to the output variables are analyzed. The key parameters that play important roles in the dynamics of the output variables of the equivalent model are identified and included in further parameter estimation. Particle Swarm Optimization (PSO is improved for the parameter estimation of the equivalent model. Simulations are performed in different microgrid operation conditions to evaluate the effectiveness of the equivalent model of microgrid.

  15. Generalized Constitutive Model for Stabilized Quick Clay | Bujulu ...

    African Journals Online (AJOL)

    An experimentally-based two yield surface constitutive model for cemented quick clay has been developed at NTNU, Norway, to reproduce the mechanical behavior of the stabilized quick clay in the triaxial p'-q stress space. The model takes into account the actual mechanical properties of the stabilized material, such as ...

  16. A Boundary Layer Parameterization for a General Model.

    Science.gov (United States)

    1984-03-01

    evaluation of grassland evapotrans- piration. Agric. Meteor., 11, 373-383. O’Neill, P., L. Pochop and J. Borrelli , 1979: Urban lawn evapotranspiration...model development in this report is original in nature. The software logistics of the combination of these models is described in the User’s Manual

  17. General model and control of an n rotor helicopter

    DEFF Research Database (Denmark)

    Sidea, Adriana-Gabriela; Brogaard, Rune Yding; Andersen, Nils Axel

    2015-01-01

    The purpose of this study was to create a dynamic, nonlinear mathematical model ofa multirotor that would be valid for different numbers of rotors. Furthermore, a set of SingleInput Single Output (SISO) controllers were implemented for attitude control. Both model andcontrollers were tested...

  18. A generalized regional design storm rainfall model for Botswana ...

    African Journals Online (AJOL)

    Design of drainage and dam structures involves a full understanding of the duration, magnitude and volume of peak flood flows anticipated. For gauged catchments a number of established flood frequency models and rainfall-runoff models are used widely. However, most planned developments for bridge or dam or any ...

  19. Developing a Dynamic Stochastic General Equilibrium Model for the ...

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

    NCAER is planning the project in two phases: -Phase 1: Researchers will develop a model for India based on a review of the relevant literature and consultations. They will develop a database for estimating purposes. -Phase 2: Researchers will estimate the model, operationalize it, and validate it through alternative sets of ...

  20. Guidelines for Applying the Capability Maturity Model Analysis to Connected and Automated Vehicle Deployment

    Science.gov (United States)

    2017-11-23

    The Federal Highway Administration (FHWA) has adapted the Transportation Systems Management and Operations (TSMO) Capability Maturity Model (CMM) to describe the operational maturity of Infrastructure Owner-Operator (IOO) agencies across a range of i...