WorldWideScience

Sample records for modeling techniques results

  1. Numerical modelling of radon-222 entry into houses: An outline of techniques and results

    DEFF Research Database (Denmark)

    Andersen, C.E.

    2001-01-01

    Numerical modelling is a powerful tool for studies of soil gas and radon-222 entry into houses. It is the purpose of this paper to review some main techniques and results. In the past, modelling has focused on Darcy flow of soil gas (driven by indoor–outdoor pressure differences) and combined...... diffusive and advective transport of radon. Models of different complexity have been used. The simpler ones are finite-difference models with one or two spatial dimensions. The more complex models allow for full three-dimensional and time dependency. Advanced features include: soil heterogeneity, anisotropy......, fractures, moisture, non-uniform soil temperature, non-Darcy flow of gas, and flow caused by changes in the atmospheric pressure. Numerical models can be used to estimate the importance of specific factors for radon entry. Models are also helpful when results obtained in special laboratory or test structure...

  2. Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques -- Preliminary Modeling Results Emphasizing Integration among Techniques

    International Nuclear Information System (INIS)

    Tobin, S.J.; Fensin, M.L.; Ludewigt, B.A.; Menlove, H.O.; Quiter, B.J.; Sandoval, N.P.; Swinhoe, M.T.; Thompson, S.J.

    2009-01-01

    There are a variety of motivations for quantifying Pu in spent (used) fuel assemblies by means of nondestructive assay (NDA) including the following: strengthen the capabilities of the International Atomic Energy Agencies to safeguards nuclear facilities, quantifying shipper/receiver difference, determining the input accountability value at reprocessing facilities and providing quantitative input to burnup credit determination for repositories. For the purpose of determining the Pu mass in spent fuel assemblies, twelve NDA techniques were identified that provide information about the composition of an assembly. A key point motivating the present research path is the realization that none of these techniques, in isolation, is capable of both (1) quantifying the elemental Pu mass of an assembly and (2) detecting the diversion of a significant number of pins. As such, the focus of this work is determining how to best integrate 2 or 3 techniques into a system that can quantify elemental Pu and to assess how well this system can detect material diversion. Furthermore, it is important economically to down-select among the various techniques before advancing to the experimental phase. In order to achieve this dual goal of integration and down-selection, a Monte Carlo library of PWR assemblies was created and is described in another paper at Global 2009 (Fensin et al.). The research presented here emphasizes integration among techniques. An overview of a five year research plan starting in 2009 is given. Preliminary modeling results for the Monte Carlo assembly library are presented for 3 NDA techniques: Delayed Neutrons, Differential Die-Away, and Nuclear Resonance Fluorescence. As part of the focus on integration, the concept of 'Pu isotopic correlation' is discussed and the role of cooling time determination.

  3. Evaluation of data assimilation techniques for a mesoscale meteorological model and their effects on air quality model results

    Energy Technology Data Exchange (ETDEWEB)

    Amicarelli, A; Pelliccioni, A [ISPESL - Dipartimento Insediamenti Produttivi e Interazione con l' Ambiente, Via Fontana Candida, 1 00040 Monteporzio Catone (RM) Italy (Italy); Finardi, S; Silibello, C [ARIANET, via Gilino 9, 20128 Milano (Italy); Gariazzo, C

    2008-05-01

    Data assimilation techniques are methods to limit the growth of errors in a dynamical model by allowing observations distributed in space and time to force (nudge) model solutions. They have become common for meteorological model applications in recent years, especially to enhance weather forecast and to support air-quality studies. In order to investigate the influence of different data assimilation techniques on the meteorological fields produced by RAMS model, and to evaluate their effects on the ozone and PM{sub 10} concentrations predicted by FARM model, several numeric experiments were conducted over the urban area of Rome, Italy, during a summer episode.

  4. Evaluation of data assimilation techniques for a mesoscale meteorological model and their effects on air quality model results

    Science.gov (United States)

    Amicarelli, A.; Gariazzo, C.; Finardi, S.; Pelliccioni, A.; Silibello, C.

    2008-05-01

    Data assimilation techniques are methods to limit the growth of errors in a dynamical model by allowing observations distributed in space and time to force (nudge) model solutions. They have become common for meteorological model applications in recent years, especially to enhance weather forecast and to support air-quality studies. In order to investigate the influence of different data assimilation techniques on the meteorological fields produced by RAMS model, and to evaluate their effects on the ozone and PM10 concentrations predicted by FARM model, several numeric experiments were conducted over the urban area of Rome, Italy, during a summer episode.

  5. Evaluation of data assimilation techniques for a mesoscale meteorological model and their effects on air quality model results

    International Nuclear Information System (INIS)

    Amicarelli, A; Pelliccioni, A; Finardi, S; Silibello, C; Gariazzo, C

    2008-01-01

    Data assimilation techniques are methods to limit the growth of errors in a dynamical model by allowing observations distributed in space and time to force (nudge) model solutions. They have become common for meteorological model applications in recent years, especially to enhance weather forecast and to support air-quality studies. In order to investigate the influence of different data assimilation techniques on the meteorological fields produced by RAMS model, and to evaluate their effects on the ozone and PM 10 concentrations predicted by FARM model, several numeric experiments were conducted over the urban area of Rome, Italy, during a summer episode

  6. An Animal Model of Abdominal Aortic Aneurysm Created with Peritoneal Patch: Technique and Initial Results

    International Nuclear Information System (INIS)

    Maynar, Manuel; Qian Zhong; Hernandez, Javier; Sun Fei; Miguel, Carmen de; Crisostomo, Veronica; Uson, Jesus; Pineda, Luis-Fernando; Espinoza, Carmen G.; Castaneda, Wilfrido R.

    2003-01-01

    The purpose of this study was to develop an abdominal aortic aneurysm model that more closely resembles themorphology of human aneurysms with potential for further growth of the sac. An infrarenal abdominal aortic aneurysm (AAA) model was created with a double-layered peritoneal patch in 27 domestic swine. The patch,measuring in average from 6 to 12 cm in length and from 2 to 3 cm in width, was sutured to the edge of an aortotomy. Pre- and postsurgical digital subtraction aortograms (DSA) were obtained to document the appearance and dimensions of the aneurysm. All animals were followed with DSA for up to 5 months. Laparoscopic examination enhanced by the use of laparoscopic ultrasound was also carried out in 2 animals to assess the aneurysm at 30 and 60 days following surgery. Histological examination was performed on 4 animals. All the animals that underwent the surgical creation of the AAA survived the surgical procedure.Postsurgical DSA demonstrated the presence of the AAA in all animals,defined as more than 50% increase in diameter. The aneurysmal mean diameter increased from the baseline of 10.27 ± 1.24 to 16.69± 2.29 mm immediately after surgery, to 27.6 ± 6.59 mm at 14 days, 32.45 ± 8.76 mm at 30 days (p <0.01), and subsequently decreased to 25.98 ± 3.75 mm at 60 days. A total of 15 animals died of aneurysmal rupture that occurred more frequently in the long aneurysms (≥6 cm in length) than the short aneurysms (<6 cm in length) during the first 2 weeks after surgery(p < 0.05). No rupture occurred beyond 16 days after surgery. Four animals survived and underwent 60-day angiographic follow-up. Laparoscopic follow-up showed strong pulses, a reddish external appearance and undetectable suture lines on the aneurysmal wall. On pathology, the patches were well incorporated into the aortic wall, the luminal wall appeared almost completely endothelialized, and cellular and matrix proliferation were noted in the aneurysmal wall. A reproducible technique for the

  7. Numerical models: Detailing and simulation techniques aimed at comparison with experimental data, support to test result interpretation

    International Nuclear Information System (INIS)

    Lin Chiwen

    2001-01-01

    This part of the presentation discusses the modelling details required and the simulation techniques available for analyses, facilitating the comparison with the experimental data and providing support for interpretation of the test results. It is organised to cover the following topics: analysis inputs; basic modelling requirements for reactor coolant system; method applicable for reactor cooling system; consideration of damping values and integration time steps; typical analytic models used for analysis of reactor pressure vessel and internals; hydrodynamic mass and fluid damping for the internal analysis; impact elements for fuel analysis; and PEI theorem and its applications. The intention of these topics is to identify the key parameters associated with models of analysis and analytical methods. This should provide proper basis for useful comparison with the test results

  8. Nondestructive determination of plutonium mass in spent fuel: preliminary modeling results using the passive neutron Albedo reactivity technique

    International Nuclear Information System (INIS)

    Evans, Louise G.; Tobin, Stephen J.; Schear, Melissa A.; Menlove, Howard O.; Lee, Sang Y.; Swinhoe, Martyn T.

    2009-01-01

    There are a variety of motivations for quantifying plutonium (Pu) in spent fuel assemblies by means of nondestructive assay (NDA) including the following: strengthening the capability of the International Atomic Energy Agency (LAEA) to safeguard nuclear facilities, quantifying shipper/receiver difference, determining the input accountability value at pyrochemical processing facilities, providing quantitative input to burnup credit and final safeguards measurements at a long-term repository. In order to determine Pu mass in spent fuel assemblies, thirteen NDA techniques were identified that provide information about the composition of an assembly. A key motivation of the present research is the realization that none of these techniques, in isolation, is capable of both (1) quantifying the Pu mass of an assembly and (2) detecting the diversion of a significant number of rods. It is therefore anticipated that a combination of techniques will be required. A 5 year effort funded by the Next Generation Safeguards Initiative (NGSI) of the U.S. DOE was recently started in pursuit of these goals. The first two years involves researching all thirteen techniques using Monte Carlo modeling while the final three years involves fabricating hardware and measuring spent fuel. Here, we present the work in two main parts: (1) an overview of this NGSI effort describing the motivations and approach being taken; (2) The preliminary results for one of the NDA techniques - Passive Neutron Albedo Reactivity (PNAR). The PNAR technique functions by using the intrinsic neutron emission of the fuel (primarily from the spontaneous fission of curium) to self-interrogate any fissile material present. Two separate measurements of the spent fuel are made, both with and without cadmium (Cd) present. The ratios of the Singles, Doubles and Triples count rates obtained in each case are analyzed; known as the Cd ratio. The primary differences between the two measurements are the neutron energy spectrum

  9. Acquisition War-Gaming Technique for Acquiring Future Complex Systems: Modeling and Simulation Results for Cost Plus Incentive Fee Contract

    Directory of Open Access Journals (Sweden)

    Tien M. Nguyen

    2018-03-01

    Full Text Available This paper provides a high-level discussion and propositions of frameworks and models for acquisition strategy of complex systems. In particular, it presents an innovative system engineering approach to model the Department of Defense (DoD acquisition process and offers several optimization modules including simulation models using game theory and war-gaming concepts. Our frameworks employ Advanced Game-based Mathematical Framework (AGMF and Unified Game-based Acquisition Framework (UGAF, and related advanced simulation and mathematical models that include a set of War-Gaming Engines (WGEs implemented in MATLAB statistical optimization models. WGEs are defined as a set of algorithms, characterizing the Program and Technical Baseline (PTB, technology enablers, architectural solutions, contract type, contract parameters and associated incentives, and industry bidding position. As a proof of concept, Aerospace, in collaboration with the North Carolina State University (NCSU and University of Hawaii (UH, successfully applied and extended the proposed frameworks and decision models to determine the optimum contract parameters and incentives for a Cost Plus Incentive Fee (CPIF contract. As a result, we can suggest a set of acquisition strategies that ensure the optimization of the PTB.

  10. Validation Techniques of network harmonic models based on switching of a series linear component and measuring resultant harmonic increments

    DEFF Research Database (Denmark)

    Wiechowski, Wojciech Tomasz; Lykkegaard, Jan; Bak, Claus Leth

    2007-01-01

    In this paper two methods of validation of transmission network harmonic models are introduced. The methods were developed as a result of the work presented in [1]. The first method allows calculating the transfer harmonic impedance between two nodes of a network. Switching a linear, series network......, as for example a transmission line. Both methods require that harmonic measurements performed at two ends of the disconnected element are precisely synchronized....... are used for calculation of the transfer harmonic impedance between the nodes. The determined transfer harmonic impedance can be used to validate a computer model of the network. The second method is an extension of the fist one. It allows switching a series element that contains a shunt branch...

  11. Techniques for sensitivity analysis of SYVAC results

    International Nuclear Information System (INIS)

    Prust, J.O.

    1985-05-01

    Sensitivity analysis techniques may be required to examine the sensitivity of SYVAC model predictions to the input parameter values, the subjective probability distributions assigned to the input parameters and to the relationship between dose and the probability of fatal cancers plus serious hereditary disease in the first two generations of offspring of a member of the critical group. This report mainly considers techniques for determining the sensitivity of dose and risk to the variable input parameters. The performance of a sensitivity analysis technique may be improved by decomposing the model and data into subsets for analysis, making use of existing information on sensitivity and concentrating sampling in regions the parameter space that generates high doses or risks. A number of sensitivity analysis techniques are reviewed for their application to the SYVAC model including four techniques tested in an earlier study by CAP Scientific for the SYVAC project. This report recommends the development now of a method for evaluating the derivative of dose and parameter value and extending the Kruskal-Wallis technique to test for interactions between parameters. It is also recommended that the sensitivity of the output of each sub-model of SYVAC to input parameter values should be examined. (author)

  12. Advanced Atmospheric Ensemble Modeling Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Chiswell, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kurzeja, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Maze, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Viner, B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Werth, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-29

    Ensemble modeling (EM), the creation of multiple atmospheric simulations for a given time period, has become an essential tool for characterizing uncertainties in model predictions. We explore two novel ensemble modeling techniques: (1) perturbation of model parameters (Adaptive Programming, AP), and (2) data assimilation (Ensemble Kalman Filter, EnKF). The current research is an extension to work from last year and examines transport on a small spatial scale (<100 km) in complex terrain, for more rigorous testing of the ensemble technique. Two different release cases were studied, a coastal release (SF6) and an inland release (Freon) which consisted of two release times. Observations of tracer concentration and meteorology are used to judge the ensemble results. In addition, adaptive grid techniques have been developed to reduce required computing resources for transport calculations. Using a 20- member ensemble, the standard approach generated downwind transport that was quantitatively good for both releases; however, the EnKF method produced additional improvement for the coastal release where the spatial and temporal differences due to interior valley heating lead to the inland movement of the plume. The AP technique showed improvements for both release cases, with more improvement shown in the inland release. This research demonstrated that transport accuracy can be improved when models are adapted to a particular location/time or when important local data is assimilated into the simulation and enhances SRNL’s capability in atmospheric transport modeling in support of its current customer base and local site missions, as well as our ability to attract new customers within the intelligence community.

  13. Mathematical modelling techniques

    CERN Document Server

    Aris, Rutherford

    1995-01-01

    ""Engaging, elegantly written."" - Applied Mathematical ModellingMathematical modelling is a highly useful methodology designed to enable mathematicians, physicists and other scientists to formulate equations from a given nonmathematical situation. In this elegantly written volume, a distinguished theoretical chemist and engineer sets down helpful rules not only for setting up models but also for solving the mathematical problems they pose and for evaluating models.The author begins with a discussion of the term ""model,"" followed by clearly presented examples of the different types of mode

  14. Multi-scale model of the ionosphere from the combination of modern space-geodetic satellite techniques - project status and first results

    Science.gov (United States)

    Schmidt, M.; Hugentobler, U.; Jakowski, N.; Dettmering, D.; Liang, W.; Limberger, M.; Wilken, V.; Gerzen, T.; Hoque, M.; Berdermann, J.

    2012-04-01

    Near real-time high resolution and high precision ionosphere models are needed for a large number of applications, e.g. in navigation, positioning, telecommunications or astronautics. Today these ionosphere models are mostly empirical, i.e., based purely on mathematical approaches. In the DFG project 'Multi-scale model of the ionosphere from the combination of modern space-geodetic satellite techniques (MuSIK)' the complex phenomena within the ionosphere are described vertically by combining the Chapman electron density profile with a plasmasphere layer. In order to consider the horizontal and temporal behaviour the fundamental target parameters of this physics-motivated approach are modelled by series expansions in terms of tensor products of localizing B-spline functions depending on longitude, latitude and time. For testing the procedure the model will be applied to an appropriate region in South America, which covers relevant ionospheric processes and phenomena such as the Equatorial Anomaly. The project connects the expertise of the three project partners, namely Deutsches Geodätisches Forschungsinstitut (DGFI) Munich, the Institute of Astronomical and Physical Geodesy (IAPG) of the Technical University Munich (TUM) and the German Aerospace Center (DLR), Neustrelitz. In this presentation we focus on the current status of the project. In the first year of the project we studied the behaviour of the ionosphere in the test region, we setup appropriate test periods covering high and low solar activity as well as winter and summer and started the data collection, analysis, pre-processing and archiving. We developed partly the mathematical-physical modelling approach and performed first computations based on simulated input data. Here we present information on the data coverage for the area and the time periods of our investigations and we outline challenges of the multi-dimensional mathematical-physical modelling approach. We show first results, discuss problems

  15. Boundary representation modelling techniques

    CERN Document Server

    2006-01-01

    Provides the most complete presentation of boundary representation solid modelling yet publishedOffers basic reference information for software developers, application developers and users Includes a historical perspective as well as giving a background for modern research.

  16. Atmospheric Deposition Modeling Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides data on model results for dry and total deposition of sulfur, nitrogen and base cation species. Components include deposition velocities, dry...

  17. New techniques for subdivision modelling

    OpenAIRE

    BEETS, Koen

    2006-01-01

    In this dissertation, several tools and techniques for modelling with subdivision surfaces are presented. Based on the huge amount of theoretical knowledge about subdivision surfaces, we present techniques to facilitate practical 3D modelling which make subdivision surfaces even more useful. Subdivision surfaces have reclaimed attention several years ago after their application in full-featured 3D animation movies, such as Toy Story. Since then and due to their attractive properties an ever i...

  18. Survey of semantic modeling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.L.

    1975-07-01

    The analysis of the semantics of programing languages was attempted with numerous modeling techniques. By providing a brief survey of these techniques together with an analysis of their applicability for answering semantic issues, this report attempts to illuminate the state-of-the-art in this area. The intent is to be illustrative rather than thorough in the coverage of semantic models. A bibliography is included for the reader who is interested in pursuing this area of research in more detail.

  19. Saturation of superstorms and finite compressibility of the magnetosphere: Results of the magnetogram inversion technique and global PPMLR-MHD model

    Science.gov (United States)

    Mishin, V. V.; Mishin, V. M.; Karavaev, Yu.; Han, J. P.; Wang, C.

    2016-07-01

    We report on novel features of the saturation process of the polar cap magnetic flux and Poynting flux into the magnetosphere from the solar wind during three superstorms. In addition to the well-known effect of the interplanetary electric (Esw) and southward magnetic (interplanetary magnetic field (IMF) Bz) fields, we found that the saturation depends also on the solar wind ram pressure Pd. By means of the magnetogram inversion technique and a global MHD numerical model Piecewise Parabolic Method with a Lagrangian Remap, we explore the dependence of the magnetopause standoff distance on ram pressure and the southward IMF. Unlike earlier studies, in the considered superstorms both Pd and Bz achieve extreme values. As a result, we show that the compression rate of the dayside magnetosphere decreases with increasing Pd and the southward Bz, approaching very small values for extreme Pd ≥ 15 nPa and Bz ≤ -40 nT. This dependence suggests that finite compressibility of the magnetosphere controls saturation of superstorms.

  20. Investigations of auroral dynamics: techniques and results

    International Nuclear Information System (INIS)

    Steen, Aa.

    1988-10-01

    This study is an experimental investigation of the dynamics of the aurora, describing both the systems developed for the optical measurements and the results obtained. It is found that during a auroral arc deformation, a fold travelling eastward along the arc is associated with an enhanced F-region ion temperature of 2700 K, measured by EISCAT, indicative of enhanced ionspheric electric fields. It is shown that for an auroral break-up, the large-scale westward travelling surge (WTS) is the last developed spiral in a sequence of spiral formations. It is proposed that the Kelvin-Helmholtz instability is the responsible process. In another event it is shown that large-amplitude long-lasting pulsations, observed both in ground-based magnetic field and photometer recordings, correspond to strong modulations of the particle intensity at the equatorial orbit (6.6 Re). In this event a gradual transition occurs between pulses classified as Ps6/auroral torches toward pulses with characteristics of substorms. The observations are explained by the Kelvin-Helmholtz instability in a magnetospheric boundary layer. The meridional neutral wind, at about 240 km altitude, is found to be reduced prior to or at the onset of auroral activity. These findings are suggestive of large-scale reconfigurations of the ionspheric electric fields prior to auroral onsets. A new real time triangulation technique developed to determine the altitude of auroral arcs is presented, and an alternative method to analyze incoherent scatter data is discussed. (With 46 refs.) (author)

  1. Verification of Orthogrid Finite Element Modeling Techniques

    Science.gov (United States)

    Steeve, B. E.

    1996-01-01

    The stress analysis of orthogrid structures, specifically with I-beam sections, is regularly performed using finite elements. Various modeling techniques are often used to simplify the modeling process but still adequately capture the actual hardware behavior. The accuracy of such 'Oshort cutso' is sometimes in question. This report compares three modeling techniques to actual test results from a loaded orthogrid panel. The finite element models include a beam, shell, and mixed beam and shell element model. Results show that the shell element model performs the best, but that the simpler beam and beam and shell element models provide reasonable to conservative results for a stress analysis. When deflection and stiffness is critical, it is important to capture the effect of the orthogrid nodes in the model.

  2. MR arthrography: Basics, technique, and first results

    International Nuclear Information System (INIS)

    Hajek, P.C.; Engel, A.; Kramer, J.; Imhof, H.

    1988-01-01

    Following evidence that intraarticular Gd-DTPA does not induce synovitis and is not stored in normal or chondropathic joint cartilage, the authors injected various concentrations of Gd-DTPA into 40 cadaveric and 40 in vivo knees. All in vivo knees underwent total prosthetic knee replacement, followed by a histologic workup. Results showed that MR arthrography greatly enhances the visibility of normal and pathologic structures and is a safe procedure. Moreover, MR arthrography seems to allow correct assessment and staging of various types of chondropathies

  3. Robotic presacral neurectomy - technique and results.

    Science.gov (United States)

    Kapetanakis, Vasilis; Jacob, Kristina; Klauschie, Jennifer; Kho, Rosanne; Magrina, Javier

    2012-03-01

    The feasibility, safety and outcomes of robotic presacral neurectomy were evaluated. A retrospective analysis was performed of 33 patients with midline chronic pelvic pain, who underwent robotic presacral neurectomy. Data were collected during the period March 2004-March 2010. All patients underwent robotic presacral neurectomy and additional robotic procedures. Mean operating time for robotic presacral neurectomy was 5.8 (range 4.4-6.9) min. Mean blood loss, including concomitant procedures, was 39 (range 15-150) ml. Most patients were discharged the same day (60%) and mean hospital stay was 0.39 (range 0-2) days. There were no conversions or intra-operative complications. There were two postoperative complications: one pelvic abscess and one Clostridium difficile colitis. Pain improvement was reported by 73% (22/30) of patients. Robotic presacral neurectomy is safe and feasible, resulting in improvement of pelvic pain in selected patients. Copyright © 2011 John Wiley & Sons, Ltd.

  4. Mandibular distraction in neonates: indications, technique, results

    Directory of Open Access Journals (Sweden)

    Sesenna Enrico

    2012-02-01

    Full Text Available Abstract Background The Pierre Robin Sequence features were first described by Robin in 1923 and include micrognathia, glossoptosis and respiratory distress with an incidence estimated as 1:8,500 to 1:20,000 newborns. Upper airway obstruction and feeding difficulties are the main concerns related to the pathology. Mandibular distraction should be considered a treatment option (when other treatments result inadequate. Patiants and methods Ten patients between the ages of 1 month and 2 years with severe micrognathia and airway obstruction were treated with Mandibular Distraction Osteogenesis (MDO. All patients underwent fibroscopic examination of the upper airway and a radiographic imaging and/or computed tomography scans to detect malformations and to confirm that the obstruction was caused by posterior tongue displacement. All patients were evaluated by a multidisciplinary team. Indications for surgery included frequent apneic episodes with severe desaturation (70%. Gavage therapy was employed in all patients since oral feeding was not possible. The two tracheotomy patients were 5 months and 2 years old respectively, and the distraction procedure was performed to remove the tracheotomy tube. All patients were treated with bilateral mandibular distraction: two cases with an external multivector distraction device, six cases with an internal non-resorbable device and two cases with an internal resorbable device. In one case, the patient with Goldenhar's Syndrome, the procedure was repeated. Results The resolution of symptoms was obtained in all patients, and, when present, tracheotomy was removed without complications. Of the two patients with pre-existing tracheotomies, in the younger patient (5 months old the tracheotomy was removed 7 days postoperatively. In the Goldenhar's syndrome case (2 years old a Montgomery device was necessary for 6 months due to the presence of tracheotomy-inducted tracheomalacia. Patients were discharged when the

  5. A Comparative of business process modelling techniques

    Science.gov (United States)

    Tangkawarow, I. R. H. T.; Waworuntu, J.

    2016-04-01

    In this era, there is a lot of business process modeling techniques. This article is the research about differences of business process modeling techniques. For each technique will explain about the definition and the structure. This paper presents a comparative analysis of some popular business process modelling techniques. The comparative framework is based on 2 criteria: notation and how it works when implemented in Somerleyton Animal Park. Each technique will end with the advantages and disadvantages. The final conclusion will give recommend of business process modeling techniques that easy to use and serve the basis for evaluating further modelling techniques.

  6. Ice911 Research: A Reversible Localized Geo-Engineering Technique to Mitigate Climate Change Effects: Field Testing, Instrumentation and Climate Modeling Results

    Science.gov (United States)

    Field, L. A.; Sholtz, A.; Chetty, S.; Manzara, A.; Johnson, D.; Christodoulou, E.; Decca, R.; Walter, P.; Katuri, K.; Bhattacharyya, S.; Ivanova, D.; Mlaker, V.; Perovich, D. K.

    2017-12-01

    This work uses ecologically benign surface treatment of silica-based materials in carefully selected, limited areas to reduce polar ice melt by reflecting energy from summertime polar sun to attempt to slow ice loss due to the Ice-Albedo Feedback Effect. Application of Ice911's materials can be accomplished within a season, at a comparatively low cost, and with far less secondary environmental impact than many other proposed geo-engineering solutions. Field testing, instrumentation, safety testing, data-handling and modeling results will be presented. The albedo modification has been tested over a number of melt seasons with an evolving array of instrumentation, at multiple sites and on progressively larger scales, most recently in a small artificial pond in Minnesota and in a lake in Barrow, Alaska's BEO (Barrow Experimental Observatory) area. The test data show that the glass bubbles can provide an effective material for increasing albedo, significantly reducing the melting rate of ice. Using NCAR's CESM package the environmental impact of the approach of surface albedo modification was studied. During two separate runs, region-wide Arctic albedo modification as well as more targeted localized treatments were modeled and compared. The parameters of a surface snow layer are used as a proxy to simulate Ice911's high-albedo materials, and the modification is started in January over selected ice/snow regions in the Arctic. Preliminary results show promising possibilities of enhancements in surface albedo, sea ice area and sea-ice concentration, as well as temperature reductions of .5 to 3 degree Kelvin in the Arctic, and global average temperature reductions of .5 to 1 degrees.

  7. Technique Development Results for the Study of a Novel Dexamethasone Impregnated Bandage Contact Lens in a Rabbit Model After Photorefractive Keratectomy

    Science.gov (United States)

    2017-10-22

    PRK Inflammation in a Rabbit Model Timothy A. Soekenl, Michael Merkley!, Wesley Brundridgel, Gary Legaultl, Matthew Caldwelll, Joseph Ciolino2...7 .0 Dexamethasone Impregnated Contact Lenses in the Treatment of Post- PRK Inflammation · in a Rabbit Model Timothy A. Soeken 1, Michael Merkley1

  8. Performability Modelling Tools, Evaluation Techniques and Applications

    NARCIS (Netherlands)

    Haverkort, Boudewijn R.H.M.

    1990-01-01

    This thesis deals with three aspects of quantitative evaluation of fault-tolerant and distributed computer and communication systems: performability evaluation techniques, performability modelling tools, and performability modelling applications. Performability modelling is a relatively new

  9. PND fuel handling decontamination program: specialized techniques and results

    International Nuclear Information System (INIS)

    Pan, R.; Hobbs, K.; Minnis, M.; Graham, K.

    1995-01-01

    The use of various decontamination techniques and equipment has become a critical part of Fuel Handling maintenance work at the Pickering Nuclear Station, an eight unit CANDU station located about 30 km east of Toronto. This paper presents an overview of the set up and techniques used for cleaning in the PND Fuel Handling Maintenance Facility, and the results achieved. (author)

  10. The Common Technique for Analyzing the Financial Results Report

    Directory of Open Access Journals (Sweden)

    Pasternak Maria M.

    2017-04-01

    Full Text Available The article is aimed at generalizing the theoretical approaches to the structure and elements of the technique for analysis of the Financial results report (Cumulative income report and providing suggestions for its improvement. The current methods have been analyzed, relevance of the application of a common technique for such analysis has been substantiated. A common technique for analyzing the Financial results report has been proposed, which includes definition of the objectives and tasks of analysis, subjects and objects of analysis, sources of its information. Stages of such an analysis were allocated and described. The findings of the article can be used to theoretically substantiate and to practically develop a technique for analyzing the Financial results report in the branches of Ukrainian economy.

  11. Probabilistic evaluation of process model matching techniques

    NARCIS (Netherlands)

    Kuss, Elena; Leopold, Henrik; van der Aa, Han; Stuckenschmidt, Heiner; Reijers, Hajo A.

    2016-01-01

    Process model matching refers to the automatic identification of corresponding activities between two process models. It represents the basis for many advanced process model analysis techniques such as the identification of similar process parts or process model search. A central problem is how to

  12. Model Checking Markov Chains: Techniques and Tools

    NARCIS (Netherlands)

    Zapreev, I.S.

    2008-01-01

    This dissertation deals with four important aspects of model checking Markov chains: the development of efficient model-checking tools, the improvement of model-checking algorithms, the efficiency of the state-space reduction techniques, and the development of simulation-based model-checking

  13. National Alliance of Business Sales Techniques and Results (STAR).

    Science.gov (United States)

    Golightly, Steven J.

    This paper presents an overview of the Sales Techniques and Results (STAR) training program developed by the National Alliance of Business in conjunction with IBM. The STAR training program can be used to help vocational directors, teachers, and counselors to be better salespersons for cooperative education or job placement programs. The paper…

  14. Advanced structural equation modeling issues and techniques

    CERN Document Server

    Marcoulides, George A

    2013-01-01

    By focusing primarily on the application of structural equation modeling (SEM) techniques in example cases and situations, this book provides an understanding and working knowledge of advanced SEM techniques with a minimum of mathematical derivations. The book was written for a broad audience crossing many disciplines, assumes an understanding of graduate level multivariate statistics, including an introduction to SEM.

  15. VLBI FOR GRAVITY PROBE B. IV. A NEW ASTROMETRIC ANALYSIS TECHNIQUE AND A COMPARISON WITH RESULTS FROM OTHER TECHNIQUES

    International Nuclear Information System (INIS)

    Lebach, D. E.; Ratner, M. I.; Shapiro, I. I.; Bartel, N.; Bietenholz, M. F.; Lederman, J. I.; Ransom, R. R.; Campbell, R. M.; Gordon, D.; Lestrade, J.-F.

    2012-01-01

    When very long baseline interferometry (VLBI) observations are used to determine the position or motion of a radio source relative to reference sources nearby on the sky, the astrometric information is usually obtained via (1) phase-referenced maps or (2) parametric model fits to measured fringe phases or multiband delays. In this paper, we describe a 'merged' analysis technique which combines some of the most important advantages of these other two approaches. In particular, our merged technique combines the superior model-correction capabilities of parametric model fits with the ability of phase-referenced maps to yield astrometric measurements of sources that are too weak to be used in parametric model fits. We compare the results from this merged technique with the results from phase-referenced maps and from parametric model fits in the analysis of astrometric VLBI observations of the radio-bright star IM Pegasi (HR 8703) and the radio source B2252+172 nearby on the sky. In these studies we use central-core components of radio sources 3C 454.3 and B2250+194 as our positional references. We obtain astrometric results for IM Peg with our merged technique even when the source is too weak to be used in parametric model fits, and we find that our merged technique yields astrometric results superior to the phase-referenced mapping technique. We used our merged technique to estimate the proper motion and other astrometric parameters of IM Peg in support of the NASA/Stanford Gravity Probe B mission.

  16. Percutaneous radiofrequency ablation of osteoid osteomas. Technique and results

    International Nuclear Information System (INIS)

    Bruners, P.; Penzkofer, T.; Guenther, R. W.; Mahnken, A.

    2009-01-01

    Purpose: Osteoid osteoma is a benign primary bone tumor that typically occurs in children and young adults. Besides local pain, which is often worse at night, prompt relief due to medication with acetylsalicylic acid (ASS) is characteristic for this bone lesion. Because long-term medication with ASS does not represent an alternative treatment strategy due to its potentially severe side effects, different minimally invasive image-guided techniques for the therapy of osteoid osteoma have been developed. In this context radiofrequency (RF) ablation in particular has become part of the clinical routine. The technique and results of image-guided RF ablation are compared to alternative treatment strategies. Materials and Methods: Using this technique, an often needle-shaped RF applicator is percutaneously placed into the tumor under image guidance. Then a high-frequency alternating current is applied by the tip of the applicator which leads to ionic motion within the tissue resulting in local heat development and thus in thermal destruction of the surrounding tissue including the tumor. Results: The published primary and secondary success rates of this technique are 87 and 83%, respectively. Surgical resection and open curettage show comparable success rates but are associated with higher complication rates. In addition image-guided RF ablation of osteoid osteomas is associated with low costs. (orig.)

  17. New quantitative safety standards: different techniques, different results?

    International Nuclear Information System (INIS)

    Rouvroye, J.L.; Brombacher, A.C.

    1999-01-01

    Safety Instrumented Systems (SIS) are used in the process industry to perform safety functions. Many factors can influence the safety of a SIS like system layout, diagnostics, testing and repair. In standards like the German DIN no quantitative analysis is demanded (DIN V 19250 Grundlegende Sicherheitsbetrachtungen fuer MSR-Schutzeinrichtungen, Berlin, 1994; DIN/VDE 0801 Grundsaetze fuer Rechner in Systemen mit Sicherheitsaufgaben, Berlin, 1990). The analysis according to these standards is based on expert opinion and qualitative analysis techniques. New standards like the IEC 61508 (IEC 61508 Functional safety of electrical/electronic/programmable electronic safety-related systems, IEC, Geneve, 1997) and the ISA-S84.01 (ISA-S84.01.1996 Application of Safety Instrumented Systems for the Process Industries, Instrument Society of America, Research Triangle Park, 1996) require quantitative risk analysis but do not prescribe how to perform the analysis. Earlier publications of the authors (Rouvroye et al., Uncertainty in safety, new techniques for the assessment and optimisation of safety in process industry, D W. Pyatt (ed), SERA-Vol. 4, Safety engineering and risk analysis, ASME, New York 1995; Rouvroye et al., A comparison study of qualitative and quantitative analysis techniques for the assessment of safety in industry, P.C. Cacciabue, I.A. Papazoglou (eds), Proceedings PSAM III conference, Crete, Greece, June 1996) have shown that different analysis techniques cover different aspects of system behaviour. This paper shows by means of a case study, that different (quantitative) analysis techniques may lead to different results. The consequence is that the application of the standards to practical systems will not always lead to unambiguous results. The authors therefore propose a technique to overcome this major disadvantage

  18. Recent applications of nuclear medicine techniques and results in Vietnam

    International Nuclear Information System (INIS)

    Phan Sy An

    2008-01-01

    The author presented recent applications of nuclear medicine techniques and results in Vietnam. The author concentrated some valuable and helpful studies such as functional tests, myocardial perfusion scintigraphy, bone, thyroid, lung, kidney and gastrointestinal tract scintigraphy for diagnosis. The results of RIA and IRMA concerning with thyroid diseases, cancer, microalbuminuria and TSH in blood spot on paper for screening of congenital hypothyroidism in new born babies were also given. The report also mentioned results of liver cancer and palliative bone metastasis treatments in Vietnam. A new technique using gamma probe in surgery for breast cancer was presented. The author introduced some modern teleradiotherapeutic modalities such as cyberknif, gamma knife, gamma rotating systeme and linac recently installed in Vietnam. (author)

  19. A Strategy Modelling Technique for Financial Services

    OpenAIRE

    Heinrich, Bernd; Winter, Robert

    2004-01-01

    Strategy planning processes often suffer from a lack of conceptual models that can be used to represent business strategies in a structured and standardized form. If natural language is replaced by an at least semi-formal model, the completeness, consistency, and clarity of strategy descriptions can be drastically improved. A strategy modelling technique is proposed that is based on an analysis of modelling requirements, a discussion of related work and a critical analysis of generic approach...

  20. Model techniques for testing heated concrete structures

    International Nuclear Information System (INIS)

    Stefanou, G.D.

    1983-01-01

    Experimental techniques are described which may be used in the laboratory to measure strains of model concrete structures representing to scale actual structures of any shape or geometry, operating at elevated temperatures, for which time-dependent creep and shrinkage strains are dominant. These strains could be used to assess the distribution of stress in the scaled structure and hence to predict the actual behaviour of concrete structures used in nuclear power stations. Similar techniques have been employed in an investigation to measure elastic, thermal, creep and shrinkage strains in heated concrete models representing to scale parts of prestressed concrete pressure vessels for nuclear reactors. (author)

  1. Improved modeling techniques for turbomachinery flow fields

    Energy Technology Data Exchange (ETDEWEB)

    Lakshminarayana, B. [Pennsylvania State Univ., University Park, PA (United States); Fagan, J.R. Jr. [Allison Engine Company, Indianapolis, IN (United States)

    1995-10-01

    This program has the objective of developing an improved methodology for modeling turbomachinery flow fields, including the prediction of losses and efficiency. Specifically, the program addresses the treatment of the mixing stress tensor terms attributed to deterministic flow field mechanisms required in steady-state Computational Fluid Dynamic (CFD) models for turbo-machinery flow fields. These mixing stress tensors arise due to spatial and temporal fluctuations (in an absolute frame of reference) caused by rotor-stator interaction due to various blade rows and by blade-to-blade variation of flow properties. These tasks include the acquisition of previously unavailable experimental data in a high-speed turbomachinery environment, the use of advanced techniques to analyze the data, and the development of a methodology to treat the deterministic component of the mixing stress tensor. Penn State will lead the effort to make direct measurements of the momentum and thermal mixing stress tensors in high-speed multistage compressor flow field in the turbomachinery laboratory at Penn State. They will also process the data by both conventional and conditional spectrum analysis to derive momentum and thermal mixing stress tensors due to blade-to-blade periodic and aperiodic components, revolution periodic and aperiodic components arising from various blade rows and non-deterministic (which includes random components) correlations. The modeling results from this program will be publicly available and generally applicable to steady-state Navier-Stokes solvers used for turbomachinery component (compressor or turbine) flow field predictions. These models will lead to improved methodology, including loss and efficiency prediction, for the design of high-efficiency turbomachinery and drastically reduce the time required for the design and development cycle of turbomachinery.

  2. Numerical modeling techniques for flood analysis

    Science.gov (United States)

    Anees, Mohd Talha; Abdullah, K.; Nawawi, M. N. M.; Ab Rahman, Nik Norulaini Nik; Piah, Abd. Rahni Mt.; Zakaria, Nor Azazi; Syakir, M. I.; Mohd. Omar, A. K.

    2016-12-01

    Topographic and climatic changes are the main causes of abrupt flooding in tropical areas. It is the need to find out exact causes and effects of these changes. Numerical modeling techniques plays a vital role for such studies due to their use of hydrological parameters which are strongly linked with topographic changes. In this review, some of the widely used models utilizing hydrological and river modeling parameters and their estimation in data sparse region are discussed. Shortcomings of 1D and 2D numerical models and the possible improvements over these models through 3D modeling are also discussed. It is found that the HEC-RAS and FLO 2D model are best in terms of economical and accurate flood analysis for river and floodplain modeling respectively. Limitations of FLO 2D in floodplain modeling mainly such as floodplain elevation differences and its vertical roughness in grids were found which can be improve through 3D model. Therefore, 3D model was found to be more suitable than 1D and 2D models in terms of vertical accuracy in grid cells. It was also found that 3D models for open channel flows already developed recently but not for floodplain. Hence, it was suggested that a 3D model for floodplain should be developed by considering all hydrological and high resolution topographic parameter's models, discussed in this review, to enhance the findings of causes and effects of flooding.

  3. Results of arthrospine assisted percutaneous technique for lumbar discectomy

    Directory of Open Access Journals (Sweden)

    Mohinder Kaushal

    2016-01-01

    Full Text Available Background: Avaialable minimal invasive arthro/endoscopic techniques are not compatible with 30 degree arthroscope which orthopedic surgeons uses in knee and shoulder arthroscopy. Minimally invasive “Arthrospine assisted percutaneous technique for lumbar discectomy” is an attempt to allow standard familiar microsurgical discectomy and decompression to be performed using 30° arthroscope used in knee and shoulder arthroscopy with conventional micro discectomy instruments. Materials and Methods: 150 patients suffering from lumbar disc herniations were operated between January 2004 and December 2012 by indiginously designed Arthrospine system and were evaluated retrospectively. In lumbar discectomy group, there were 85 males and 65 females aged between 18 and 72 years (mean, 38.4 years. The delay between onset of symptoms to surgery was between 3 months to 7 years. Levels operated upon included L1-L2 (n = 3, L2-L3 (n = 2, L3-L4 (n = 8, L4-L5 (n = 90, and L5-S1 (n = 47. Ninety patients had radiculopathy on right side and 60 on left side. There were 22 central, 88 paracentral, 12 contained, 3 extraforaminal, and 25 sequestrated herniations. Standard protocol of preoperative blood tests, x-ray LS Spine and pre operative MRI and pre anaesthetic evaluation for anaesthesia was done in all cases. Technique comprised localization of symptomatic level followed by percutaneous dilatation and insertion of a newly devised arthrospine system devise over a dilator through a 15 mm skin and fascial incision. Arthro/endoscopic discectomy was then carried out by 30° arthroscope and conventional disc surgery instruments. Results: Based on modified Macnab's criteria, of 150 patients operated for lumbar discectomy, 136 (90% patients had excellent to good, 12 (8% had fair, and 2 patients (1.3% had poor results. The complications observed were discitis in 3 patients (2%, dural tear in 4 patients (2.6%, and nerve root injury in 2 patients (1.3%. About 90% patients

  4. Hydroponic cultivation techniques: good results with Eg system

    Energy Technology Data Exchange (ETDEWEB)

    Mimiola, G; Sigliuzzo, C [Tecnagro, Valenzano (Italy)

    1988-12-01

    This report describes results obtained at the Tecnagro agronomic institute (Valenzano, Italy) in which research is being carried out on the use of the Eg hydroponic system developed in Israel. The research program examined the following: composition of nutritive solutions for ornamental plants and vegetables, methods of application of nutritive substances, breeding densities for ornamental plants and vegetables. Successful nutritive formulas were obtained which resulted, in the case of ornamental plants, in increases in plant height (from 30 to 50%), foliage area (50%), as well as, in shortened growth cycles. For vegetables, shortened growth cycles were developed along with a greater and more consistant production. From the economics point of view, tomatoes proved to be the best choice of vegetable for cultivation with the Eg technique.

  5. Labia Majora Augmentation with Hyaluronic Acid Filler: Technique and Results.

    Science.gov (United States)

    Fasola, Elena; Gazzola, Riccardo

    2016-11-01

    External female genitalia lose elasticity and volume with age. In the literature several techniques address the redundancy of the labia minora, but only few reports describe the augmentation of labia majora with fat grafting. At present, no studies describe the augmentation of the labia majora with hyaluronic acid. This study aims to present our technique of infiltration of hyaluronic acid filler, analyzing effectiveness, patient satisfaction, and complications. We retrospectively analyzed 54 patients affected by hypotrophy of the labia majora; they were treated with hyaluronic acid filler between November 2010 and December 2014. The Global Aesthetic Improvement Scale (GAIS) filled out by the doctor and the patients was used to evaluate the results 12 months after the infiltration. Complications were recorded. A total of 31 patients affected by mild to moderate labia majora hypotrophy were treated with 19 mg/mL HA filler; 23 patients affected by severe labia majora hypotrophy were treated with 21 mg/mL HA filler. Among the first group of patients, one underwent a second infiltration 6 months later with 19 mg/mL HA filler (maximum 1 mL). A significant improvement (P labia majora is able to provide a significant rejuvenation with a simple outpatient procedure. We achieved significant improvements with one infiltration in all cases. The treatment is repeatable, has virtually no complications and it is reversible. 4 Therapeutic. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  6. Comparative data compression techniques and multi-compression results

    International Nuclear Information System (INIS)

    Hasan, M R; Ibrahimy, M I; Motakabber, S M A; Ferdaus, M M; Khan, M N H

    2013-01-01

    Data compression is very necessary in business data processing, because of the cost savings that it offers and the large volume of data manipulated in many business applications. It is a method or system for transmitting a digital image (i.e., an array of pixels) from a digital data source to a digital data receiver. More the size of the data be smaller, it provides better transmission speed and saves time. In this communication, we always want to transmit data efficiently and noise freely. This paper will provide some compression techniques for lossless text type data compression and comparative result of multiple and single compression, that will help to find out better compression output and to develop compression algorithms

  7. Technique and results of femoral bifurcation endarterectomy by eversion.

    Science.gov (United States)

    Dufranc, Julie; Palcau, Laura; Heyndrickx, Maxime; Gouicem, Djelloul; Coffin, Olivier; Felisaz, Aurélien; Berger, Ludovic

    2015-03-01

    This study evaluated, in a contemporary prospective series, the safety and efficacy of femoral endarterectomy using the eversion technique and compared our results with results obtained in the literature for the standard endarterectomy with patch closure. Between 2010 and 2012, 121 patients (76% male; mean age, 68.7 years; diabetes, 28%; renal insufficiency, 20%) underwent 147 consecutive femoral bifurcation endarterectomies using the eversion technique, associating or not inflow or outflow concomitant revascularization. The indications were claudication in 89 procedures (60%) and critical limb ischemia in 58 (40%). Primary, primary assisted, and secondary patency of the femoral bifurcation, clinical improvement, limb salvage, and survival were assessed using Kaplan-Meier life-table analysis. Factors associated with those primary end-points were evaluated with univariate analysis. The technical success of eversion was of 93.2%. The 30-day mortality was 0%, and the complication rate was 8.2%; of which, half were local and benign. Median follow-up was 16 months (range, 1.6-31.2 months). Primary, primary assisted, and secondary patencies were, respectively, 93.2%, 97.2%, and 98.6% at 2 years. Primary, primary assisted, and secondary maintenance of clinical improvement were, respectively, 79.9%, 94.6%, and 98.6% at 2 years. The predictive factors for clinical degradation were clinical stage (Rutherford category 5 or 6, P = .024), platelet aggregation inhibitor treatment other than clopidogrel (P = .005), malnutrition (P = .025), and bad tibial runoff (P = .0016). A reintervention was necessary in 18.3% of limbs at 2 years: 2% involving femoral bifurcation, 6.1% inflow improvement, and 9.5% outflow improvement. The risk factors of reintervention were platelet aggregation inhibitor (other than clopidogrel, P = .049) and cancer (P = .011). Limb preservation at 2 years was 100% in the claudicant population. Limb salvage was 88.6% in the critical limb ischemia population

  8. Structural Modeling Using "Scanning and Mapping" Technique

    Science.gov (United States)

    Amos, Courtney L.; Dash, Gerald S.; Shen, J. Y.; Ferguson, Frederick; Noga, Donald F. (Technical Monitor)

    2000-01-01

    Supported by NASA Glenn Center, we are in the process developing a structural damage diagnostic and monitoring system for rocket engines, which consists of five modules: Structural Modeling, Measurement Data Pre-Processor, Structural System Identification, Damage Detection Criterion, and Computer Visualization. The function of the system is to detect damage as it is incurred by the engine structures. The scientific principle to identify damage is to utilize the changes in the vibrational properties between the pre-damaged and post-damaged structures. The vibrational properties of the pre-damaged structure can be obtained based on an analytic computer model of the structure. Thus, as the first stage of the whole research plan, we currently focus on the first module - Structural Modeling. Three computer software packages are selected, and will be integrated for this purpose. They are PhotoModeler-Pro, AutoCAD-R14, and MSC/NASTRAN. AutoCAD is the most popular PC-CAD system currently available in the market. For our purpose, it plays like an interface to generate structural models of any particular engine parts or assembly, which is then passed to MSC/NASTRAN for extracting structural dynamic properties. Although AutoCAD is a powerful structural modeling tool, the complexity of engine components requires a further improvement in structural modeling techniques. We are working on a so-called "scanning and mapping" technique, which is a relatively new technique. The basic idea is to producing a full and accurate 3D structural model by tracing on multiple overlapping photographs taken from different angles. There is no need to input point positions, angles, distances or axes. Photographs can be taken by any types of cameras with different lenses. With the integration of such a modeling technique, the capability of structural modeling will be enhanced. The prototypes of any complex structural components will be produced by PhotoModeler first based on existing similar

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

    Directory of Open Access Journals (Sweden)

    Gofrit ON

    2014-10-01

    Full Text Available Ofer N Gofrit,1 Amos Shapiro,1 Ran Katz,1 Mordechai Duvdevani,1 Vladimir Yutkin,1 Ezekiel H Landau,1 Kevin C Zorn,2 Guy Hidas,1 Dov Pode1 1Department of Urology, Hadassah Hebrew University Hospital, Jerusalem, Israel; 2Department of Surgery, Section of Urology, Montreal, Canada Background: Partial cystectomy provides oncological results comparable with those of radical cystectomy in selected patients with invasive bladder cancer without the morbidity associated with radical cystectomy and urinary diversion. We describe a novel technique of partial cystectomy that allows accurate identification of tumor margins while minimizing damage to the rest of the bladder. Methods: During the study period, 30 patients underwent partial cystectomy for invasive high-grade cancer. In 19 patients, the traditional method of tumor identification was used, ie, identifying the tumor by palpation and cystotomy. In eleven patients, after mobilization of the bladder, flexible cystoscopy was done and the light of the cystoscope was pointed toward one edge of the planned resected ellipse around the tumor, thus avoiding cystotomy. Results: Patients who underwent partial cystectomy using the novel method were similar in all characteristics to patients operated on using the traditional technique except for tumor diameter which was significantly larger in patients operated on using the novel method (4.3±1.5 cm versus 3.11±1.18 cm, P=0.032. Complications were rare in both types of surgery. The 5-year local recurrence-free survival was marginally superior using the novel method (0.8 versus 0.426, P=0.088. Overall, disease-specific and disease-free survival rates were similar. Conclusion: The use of a flexible cystoscope during partial cystectomy is a simple, low-cost maneuver that assists in planning the bladder incision and minimizes injury to the remaining bladder by avoiding the midline cystotomy. Initial oncological results show a trend toward a lower rate of local

  10. Transcorporeal cervical foraminotomy: description of technique and results

    Directory of Open Access Journals (Sweden)

    Guilherme Pereira Corrêa Meyer

    2014-09-01

    Full Text Available OBJECTIVE: Retrospective analyses of 216 patients undergoing foraminal decompression with transcorporeal approach and review of the surgical technique. METHOD: 216 patients with minimum follow-up of 2 years and an average of 41.8 months were included in the study. The clinical records of these patients were reviewed for complications, NDI (neck disability index and VAS (visual analogue scale. Pre and post-operative radiographs were used to evaluate the disc height. RESULTS: At the end of follow-up patients had significant clinical improvement with reduction of NDI of 88.3% and 86.5% and 68.3% of the VAS for neck and upper limb, respectively (p<0.05. A reduction of 8.8% of the disc height was observed without other complications associated (p<0.05. CONCLUSION: Radicular decompression through a transcorporeal approach is an alternative that provides good clinical results without the need for a fusion and with few complications.

  11. Childhood familial pheochromocytoma. Conflicting results of localization techniques

    International Nuclear Information System (INIS)

    Turner, M.C.; DeQuattro, V.; Falk, R.; Ansari, A.; Lieberman, E.

    1986-01-01

    Childhood familial pheochromocytoma was investigated in four patients by abdominal computed tomographic scan, [ 131 I]metaiodobenzylguanidine scan, and vena caval catecholamine sampling. Results conflicted with surgical findings. Computed tomographic scan identified all four adrenal tumors but missed two midline tumors in one patient. [ 131 I]metaiodobenzylguanidine scan identified two of three adrenal tumors but also suggested extra-adrenal tumors not confirmed at operation in two of three patients. Vena caval sampling for catecholamines confirmed all adrenal tumors but suggested additional tumors not verified at operation in two of three patients. All patients are asymptomatic and have normal urinary catecholamines 15 to 51 months after operation. Because of the frequency of multiple tumors in familial pheochromocytoma, different diagnostic techniques were employed. False-positive results were more frequent with [ 131 I]metaiodobenzylguanidine and vena caval sampling. Reinterpretation of the [ 131 I]metaiodobenzylguanidine scans at a later date led to less false-positive interpretation, although the false-negative rate remained unchanged. More pediatric experience with [ 131 I]metaiodobenzylguanidine scans and vena caval sampling in familial pheochromocytoma is needed. Confirmation of tumor and its localization rest with meticulous surgical exploration

  12. Field results of antifouling techniques for optical instruments

    Science.gov (United States)

    Strahle, W.J.; Hotchkiss, F.S.; Martini, Marinna A.

    1998-01-01

    An anti-fouling technique is developed for the protection of optical instruments from biofouling which leaches a bromide compound into a sample chamber and pumps new water into the chamber prior to measurement. The primary advantage of using bromide is that it is less toxic than the metal-based antifoulants. The drawback of the bromide technique is also discussed.

  13. Respirometry techniques and activated sludge models

    NARCIS (Netherlands)

    Benes, O.; Spanjers, H.; Holba, M.

    2002-01-01

    This paper aims to explain results of respirometry experiments using Activated Sludge Model No. 1. In cases of insufficient fit of ASM No. 1, further modifications to the model were carried out and the so-called "Enzymatic model" was developed. The best-fit method was used to determine the effect of

  14. Percutaneous debridement of complex pyogenic liver abscesses: technique and results

    International Nuclear Information System (INIS)

    Morettin, L.B.

    1992-01-01

    The author's approach and technique in the treatment of complex liver abscesses that persisted or recurred following percutaneous drainage are described. Six patients were treated by percutaneous debridement utilizing an instrument specifically constructed for that purpose. Four patients were chronically ill but stable. Two patients were septic, hypotensive and considered life threatened. All patients had primary pyogenic abscesses. Four had demonstrated mixed bacterial flora consisting of E. coli, Klebsiella, Proteus and gram-positive cocci and two were caused by E. coli only. In all cases a contrast-enhanced CT of the abdomen revealed multiloculated or septated abscesses containing large central debris and peripheral shell or halo of compromised hepatic parenchyma. Debridement was successful in all cases resulting in complete healing in 4-12 days. Follow-up for periods of between 1 and 4.5 years revealed no recurrences. Three cases of infected tumors of the liver were referred for treatment. CT findings in these cases demonstrated a well-developed external capsule and internal septations and the absence of a surrounding halo of compromised parenchyma distinguishes them from primary abscesses. This preliminary experience allows the conclusion that percutaneous debridement of pyogenic liver abscesses can be safely performed, can be curative in selected patients with chronic abscesses and may be life-safing in critically ill and life-threatened patients. (orig.)

  15. [Pseudo-continent perineal colostomy. Results and techniques].

    Science.gov (United States)

    Lasser, P; Dubé, P; Guillot, J M; Elias, D

    1997-09-01

    This prospective study was conducted to assess functional results obtained after pseudo-continent perineal colostomy using the Schmidt procedure. Functional outcome was assessed in 40 patients who had undergone amputation of the rectum for cancer and pseudo-continent perineal colostomy reconstruction between 1989 and 1995 in our institution. The cancer pathology, operative procedure and post-operative care were noted. Morbidity, functional outcome and degree of patient satisfaction were recorded. Mean follow-up was 45 months (18-87) in 100% of the patients. There were no operative deaths. Twenty patients had post-operative complications and 2 patients required early conversion to definitive abdominal colostomy due to severe perineal complications. Function outcome showed normal continence in 4 patients, air incontinence in 23, occasional minimal leakage in 9 and incontinence requiring iliac colostomy in 2. Eighty-six percent of the patients were highly satisfied or satisfied with their continence capacity. Pseudo-continent perineal colostomy is a reliable technique which can be proposed as an alternative to left iliac colostomy after amputation of the rectum for cancer if a rigorous procedure is applied: careful patient selection, informed consent, rigorous surgical procedure, daily life-long irrigation of the colon.

  16. Modeling techniques for quantum cascade lasers

    Energy Technology Data Exchange (ETDEWEB)

    Jirauschek, Christian [Institute for Nanoelectronics, Technische Universität München, D-80333 Munich (Germany); Kubis, Tillmann [Network for Computational Nanotechnology, Purdue University, 207 S Martin Jischke Drive, West Lafayette, Indiana 47907 (United States)

    2014-03-15

    Quantum cascade lasers are unipolar semiconductor lasers covering a wide range of the infrared and terahertz spectrum. Lasing action is achieved by using optical intersubband transitions between quantized states in specifically designed multiple-quantum-well heterostructures. A systematic improvement of quantum cascade lasers with respect to operating temperature, efficiency, and spectral range requires detailed modeling of the underlying physical processes in these structures. Moreover, the quantum cascade laser constitutes a versatile model device for the development and improvement of simulation techniques in nano- and optoelectronics. This review provides a comprehensive survey and discussion of the modeling techniques used for the simulation of quantum cascade lasers. The main focus is on the modeling of carrier transport in the nanostructured gain medium, while the simulation of the optical cavity is covered at a more basic level. Specifically, the transfer matrix and finite difference methods for solving the one-dimensional Schrödinger equation and Schrödinger-Poisson system are discussed, providing the quantized states in the multiple-quantum-well active region. The modeling of the optical cavity is covered with a focus on basic waveguide resonator structures. Furthermore, various carrier transport simulation methods are discussed, ranging from basic empirical approaches to advanced self-consistent techniques. The methods include empirical rate equation and related Maxwell-Bloch equation approaches, self-consistent rate equation and ensemble Monte Carlo methods, as well as quantum transport approaches, in particular the density matrix and non-equilibrium Green's function formalism. The derived scattering rates and self-energies are generally valid for n-type devices based on one-dimensional quantum confinement, such as quantum well structures.

  17. Modeling techniques for quantum cascade lasers

    Science.gov (United States)

    Jirauschek, Christian; Kubis, Tillmann

    2014-03-01

    Quantum cascade lasers are unipolar semiconductor lasers covering a wide range of the infrared and terahertz spectrum. Lasing action is achieved by using optical intersubband transitions between quantized states in specifically designed multiple-quantum-well heterostructures. A systematic improvement of quantum cascade lasers with respect to operating temperature, efficiency, and spectral range requires detailed modeling of the underlying physical processes in these structures. Moreover, the quantum cascade laser constitutes a versatile model device for the development and improvement of simulation techniques in nano- and optoelectronics. This review provides a comprehensive survey and discussion of the modeling techniques used for the simulation of quantum cascade lasers. The main focus is on the modeling of carrier transport in the nanostructured gain medium, while the simulation of the optical cavity is covered at a more basic level. Specifically, the transfer matrix and finite difference methods for solving the one-dimensional Schrödinger equation and Schrödinger-Poisson system are discussed, providing the quantized states in the multiple-quantum-well active region. The modeling of the optical cavity is covered with a focus on basic waveguide resonator structures. Furthermore, various carrier transport simulation methods are discussed, ranging from basic empirical approaches to advanced self-consistent techniques. The methods include empirical rate equation and related Maxwell-Bloch equation approaches, self-consistent rate equation and ensemble Monte Carlo methods, as well as quantum transport approaches, in particular the density matrix and non-equilibrium Green's function formalism. The derived scattering rates and self-energies are generally valid for n-type devices based on one-dimensional quantum confinement, such as quantum well structures.

  18. Results and techniques of multi-loop calculations

    International Nuclear Information System (INIS)

    Steinhauser, M.

    2002-01-01

    In this review some recent multi-loop results obtained in the framework of perturbative quantum chromodynamics (QCD) and quantum electrodynamics (QED) are discussed. After reviewing the most advanced techniques used for the computation of renormalization group functions, we consider the decoupling of heavy quarks. In particular, an effective method for the evaluation of the decoupling constants is presented and explicit results are given. Furthermore the connection to observables involving a scalar Higgs boson is worked out in detail. An all-order low energy v theorem is derived which establishes a relation between the coefficient functions in the hadronic Higgs decay and the decoupling constants. We review the radiative corrections of a Higgs boson into gluons and quarks and present explicit results up to order α s 4 and α s 3 , respectively. In this review special emphasis is put on the applications of asymptotic expansions. A method is described which combines expansion terms of different kinematical regions with the help of conformal mapping and Pade approximation. This method allows us to proceed beyond the present scope of exact multi-loop calculations. As far as physical processes are concerned, we review the computation of three-loop current correlators in QCD taking into account the full mass-dependence. In particular, we concentrate on the evaluation of the total cross section for the production of hadrons in e + e - annihilation. The knowledge of the complete mass dependence at order α s 2 has triggered a bunch of theory-driven analyses of the hadronic contribution to the electromagnetic coupling evaluated at high energy scales. The status is summarized in this review. In a further application four-loop diagrams are considered which contribute to the order α 2 QED corrections to the μ decay. Its relevance for the determination of the Fermi constant G F is discussed. Finally the calculation of the three-loop relation between the anti M anti S and on

  19. Rabbit tissue model (RTM) harvesting technique.

    Science.gov (United States)

    Medina, Marelyn

    2002-01-01

    A method for creating a tissue model using a female rabbit for laparoscopic simulation exercises is described. The specimen is called a Rabbit Tissue Model (RTM). Dissection techniques are described for transforming the rabbit carcass into a small, compact unit that can be used for multiple training sessions. Preservation is accomplished by using saline and refrigeration. Only the animal trunk is used, with the rest of the animal carcass being discarded. Practice exercises are provided for using the preserved organs. Basic surgical skills, such as dissection, suturing, and knot tying, can be practiced on this model. In addition, the RTM can be used with any pelvic trainer that permits placement of larger practice specimens within its confines.

  20. Microendoscopic lumbar discectomy: Technique and results of 188 cases

    Directory of Open Access Journals (Sweden)

    Arvind G Kulkarni

    2014-01-01

    Full Text Available Background: Discectomy performed open or with an operating microscope remains the standard surgical management. Tubular retractor system is being increasingly used. Potential benefits include less muscle and local damage, better cosmesis, decreased pain and operative time and faster recovery after surgery. We have evaluated the outcome of micro endoscopic discectomy (MED utilizing tubular retractors in terms of safety and efficacy of the technique. Materials and Methods: 188 consecutive patients who underwent surgery for herniated disc using the tubular retractors between April 2007 and April 2012 are reported. All patients had a preoperative MRI (Magnetic Resonance Imaging and were operated by a single surgeon with the METRx system (Medtronic, Sofamor-Danek, Memphis, TN using 18 and 16 mm ports. All patients were mobilized as soon as pain subsided and discharged within 24-48 hours post surgery. The results were evaluated by using VAS (Visual Analog Scale 0-5 for back and leg pain and ODI (Oswestry Disability Index. Patients were followed up at intervals of 1 week, 6 weeks, 3 months, 6 months, 12 months and 2 years. Results: The mean age of patients was 46 years (range 16-78 years and the sex ratio was 1.5 males to 1 female. The mean followup was 22 months (range 8-69 months. The mean VAS scale for leg pain improved from 4.14 to 0.76 ( P < 0.05 and the mean VAS scale for back pain improved from 4.1 to 0.9 ( P < 0.05. The mean ODI changed from 59.5 to 22.6 ( P < 0.05. The mean operative time per level was about 50 minutes (range 20-90 minutes. Dural punctures occurred in 11 (5% cases. Average blood loss was 30 ml (range 10-500 ml. A wrong level was identified and later corrected in a case of revision discectomy. Four patients with residual disc-herniation had revision MED and three patients with recurrent disc herniation later underwent fusion. One patient had wound infection which needed a debridement. Conclusion: MED for herniated discs

  1. Engineering model cryocooler test results

    International Nuclear Information System (INIS)

    Skimko, M.A.; Stacy, W.D.; McCormick, J.A.

    1992-01-01

    This paper reports that recent testing of diaphragm-defined, Stirling-cycle machines and components has demonstrated cooling performance potential, validated the design code, and confirmed several critical operating characteristics. A breadboard cryocooler was rebuilt and tested from cryogenic to near-ambient cold end temperatures. There was a significant increase in capacity at cryogenic temperatures and the performance results compared will with code predictions at all temperatures. Further testing on a breadboard diaphragm compressor validated the calculated requirement for a minimum axial clearance between diaphragms and mating heads

  2. UAV State Estimation Modeling Techniques in AHRS

    Science.gov (United States)

    Razali, Shikin; Zhahir, Amzari

    2017-11-01

    Autonomous unmanned aerial vehicle (UAV) system is depending on state estimation feedback to control flight operation. Estimation on the correct state improves navigation accuracy and achieves flight mission safely. One of the sensors configuration used in UAV state is Attitude Heading and Reference System (AHRS) with application of Extended Kalman Filter (EKF) or feedback controller. The results of these two different techniques in estimating UAV states in AHRS configuration are displayed through position and attitude graphs.

  3. BIOMEHANICAL MODEL OF THE GOLF SWING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Milan Čoh

    2011-08-01

    Full Text Available Golf is an extremely complex game which depends on a number of interconnected factors. One of the most important elements is undoubtedly the golf swing technique. High performance of the golf swing technique is generated by: the level of motor abilities, high degree of movement control, the level of movement structure stabilisation, morphological characteristics, inter- and intro-muscular coordination, motivation, and concentration. The golf swing technique was investigated using the biomechanical analysis method. Kinematic parameters were registered using two synchronised high-speed cameras at a frequency of 2,000 Hz. The sample of subjects consisted of three professional golf players. The study results showed a relatively high variability of the swing technique. The maximum velocity of the ball after a wood swing ranged from 233 to 227 km/h. The velocity of the ball after an iron swing was lower by 10 km/h on average. The elevation angle of the ball ranged from 11.7 to 15.3 degrees. In the final phase of the golf swing, i.e. downswing, the trunk rotators play the key role.

  4. Modern techniques in galaxy kinematics : Results from planetary nebula spectroscopy

    NARCIS (Netherlands)

    Romanowsky, AJ; Douglas, NG; Kuijken, K; Arnaboldi, M; Gerssen, J; Merrifield, MR; Kwok, S; Dopita, M; Sutherland, R

    2003-01-01

    We have observed planetary nebulae (PNe) in several early-type galaxies using new techniques on 4- to 8-meter-class telescopes. We obtain the first large data sets (greater than or similar to 100 velocities each) of PN kinematics in galaxies at greater than or similar to 15 Mpc, and present some

  5. Numerical model updating technique for structures using firefly algorithm

    Science.gov (United States)

    Sai Kubair, K.; Mohan, S. C.

    2018-03-01

    Numerical model updating is a technique used for updating the existing experimental models for any structures related to civil, mechanical, automobiles, marine, aerospace engineering, etc. The basic concept behind this technique is updating the numerical models to closely match with experimental data obtained from real or prototype test structures. The present work involves the development of numerical model using MATLAB as a computational tool and with mathematical equations that define the experimental model. Firefly algorithm is used as an optimization tool in this study. In this updating process a response parameter of the structure has to be chosen, which helps to correlate the numerical model developed with the experimental results obtained. The variables for the updating can be either material or geometrical properties of the model or both. In this study, to verify the proposed technique, a cantilever beam is analyzed for its tip deflection and a space frame has been analyzed for its natural frequencies. Both the models are updated with their respective response values obtained from experimental results. The numerical results after updating show that there is a close relationship that can be brought between the experimental and the numerical models.

  6. Transabdominal midline reconstruction by minimally invasive surgery: technique and results.

    Science.gov (United States)

    Costa, T N; Abdalla, R Z; Santo, M A; Tavares, R R F M; Abdalla, B M Z; Cecconello, I

    2016-04-01

    cases through four ports; the number of incisional hernias was 3 ± 2, with a mean maximum width of 3.75 cm (range 2.1-9) and maximum length of 14 cm (7.5-20.5). The mean surgical time was 114.3 min (range 85-170), and the median hospital stay was 1.4 days. No intra-operative or immediate post-operative complication or death occurred. One patient had a seroma treated conservatively 1 week after surgery and another had a retro-muscular infection treated with percutaneous drainage. CT-Scans made before and after the procedure, showed total closure of the defect. QOL questionnaire showed satisfaction, acceptance, and no complaints. Although the study involved a small number of patients, it has proved the technique to be feasible, easy to perform, and have the combined benefits of laparoscopic and open surgery. The results, shown by CT-scan, peri-operative, and QOL findings, were good.

  7. Translaminar screw fixation in the lumbar spine: technique, indications, results

    OpenAIRE

    Grob, D.; Humke, T.

    1998-01-01

    Translaminar screw fixation of the lumbar spine represents a simple and effective technique for short segment fusion in the degenerative spine. Clinical experience with 173 patients who underwent translaminar screw fixation revealed a fusion rate of 94%. The indications for translaminar screw fixation as a primary fixation procedure are: segmental dysfunction, lumbar spinal stenosis with painful degenerative changes, segmental revision surgery after discectomies, and painful disc-related synd...

  8. Immersive visualization of dynamic CFD model results

    International Nuclear Information System (INIS)

    Comparato, J.R.; Ringel, K.L.; Heath, D.J.

    2004-01-01

    With immersive visualization the engineer has the means for vividly understanding problem causes and discovering opportunities to improve design. Software can generate an interactive world in which collaborators experience the results of complex mathematical simulations such as computational fluid dynamic (CFD) modeling. Such software, while providing unique benefits over traditional visualization techniques, presents special development challenges. The visualization of large quantities of data interactively requires both significant computational power and shrewd data management. On the computational front, commodity hardware is outperforming large workstations in graphical quality and frame rates. Also, 64-bit commodity computing shows promise in enabling interactive visualization of large datasets. Initial interactive transient visualization methods and examples are presented, as well as development trends in commodity hardware and clustering. Interactive, immersive visualization relies on relevant data being stored in active memory for fast response to user requests. For large or transient datasets, data management becomes a key issue. Techniques for dynamic data loading and data reduction are presented as means to increase visualization performance. (author)

  9. Defining Malaysian Knowledge Society: Results from the Delphi Technique

    Science.gov (United States)

    Hamid, Norsiah Abdul; Zaman, Halimah Badioze

    This paper outlines the findings of research where the central idea is to define the term Knowledge Society (KS) in Malaysian context. The research focuses on three important dimensions, namely knowledge, ICT and human capital. This study adopts a modified Delphi technique to seek the important dimensions that can contribute to the development of Malaysian's KS. The Delphi technique involved ten experts in a five-round iterative and controlled feedback procedure to obtain consensus on the important dimensions and to verify the proposed definition of KS. The finding shows that all three dimensions proposed initially scored high and moderate consensus. Round One (R1) proposed an initial definition of KS and required comments and inputs from the panel. These inputs were then used to develop items for a R2 questionnaire. In R2, 56 out of 73 items scored high consensus and in R3, 63 out of 90 items scored high. R4 was conducted to re-rate the new items, in which 8 out of 17 items scored high. Other items scored moderate consensus and no item scored low or no consensus in all rounds. The final round (R5) was employed to verify the final definition of KS. Findings and discovery of this study are significant to the definition of KS and the development of a framework in the Malaysian context.

  10. Calibration techniques and results for the Portsmouth Cf shuffler

    International Nuclear Information System (INIS)

    Gross, J.C.; Wines, K.M.

    1993-01-01

    As environmental concerns over radioactive waste disposal continue to rise, the importance of Californium shufflers as a versatile waste monitoring and segregation instrument also continue to increase. The extent to which different amounts and types of materials can be measured by the shuffler is directly related to the extent of its calibration. As shufflers become more common place and their waste management uses also rise, the importance of a wide ranging and thorough calibration becomes critical. This paper presents the techniques used at the Portsmouth Gaseous Diffusion Plant for calibrating the shuffler to detect levels of U-235 in radioactive waste. While the calibration techniques are similar to those used by Los Alamos, the standards that were used were constructed somewhat differently so that geometric effects are maximized. Also presented are shuffler transmission measurements that are used to determine the matrix type and the corresponding calibration. A discussion of the calibration data is given. This discussion includes specific aspects of the calibration such as overall range, high end limits, and poly shielding range and usefulness

  11. Modeling with data tools and techniques for scientific computing

    CERN Document Server

    Klemens, Ben

    2009-01-01

    Modeling with Data fully explains how to execute computationally intensive analyses on very large data sets, showing readers how to determine the best methods for solving a variety of different problems, how to create and debug statistical models, and how to run an analysis and evaluate the results. Ben Klemens introduces a set of open and unlimited tools, and uses them to demonstrate data management, analysis, and simulation techniques essential for dealing with large data sets and computationally intensive procedures. He then demonstrates how to easily apply these tools to the many threads of statistical technique, including classical, Bayesian, maximum likelihood, and Monte Carlo methods

  12. FY-87 packing fabrication techniques (commercial waste form) results

    International Nuclear Information System (INIS)

    Werry, E.V.; Gates, T.E.; Cabbage, K.S.; Eklund, J.D.

    1988-04-01

    This report covers the investigation of fabrication techniques associated with the development of suitable materials and methods to provide a prefabricated packing for waste packages for the Basalt Waste Isolation Project (BWIP). The principal functions of the packing are to minimize container corrosion during the 300 to 1000 years following repository closure and provide long-term control of the release of radionuclides from the waste package. The investigative work, discussed in this report, was specifically conceived to develop the design criteria for production of full-scale prototypical packing rings. The investigative work included the preparation of procedures, the preparation of fabrication materials, physical properties, and the determination of the engineering properties. The principal activities were the preparation of the materials and the determination of the physical properties. 21 refs., 20 figs., 14 tabs

  13. Percutaneous peritoneovenous shunt positioning: technique and preliminary results

    International Nuclear Information System (INIS)

    Orsi, Franco; Grasso, Rosario Francesco; Bonomo, Guido; Marinucci, Irene; Monti, Cinzia; Bellomi, Massimo

    2002-01-01

    Nine peritoneovenous shunts were positioned by percutaneous technique in seven patients with advanced malignancy causing severe refractory ascites, and in two patients with hepatic cirrhosis (one with hepatocarcinoma). In all patients the shunts were percutaneously placed through the subclavian vein in the angiographic suite under digital fluoroscopic guide. No complications directly related to the procedure occurred. The shunt was successfully positioned in all patients in 60 min average time. No patient showed symptoms related to pulmonary overload or to disseminated intravascular coagulation. All patients had a significant improvement of the objective symptoms related to ascites such as respiratory symptoms, dyspepsia, and functional impairment to evacuation describing an improvement of their quality of life. Maximum shunt patency was 273 days. Percutaneous placement of peritoneovenous shunt is a safe, fast, and inexpensive procedure, extremely useful in resolution of refractory ascites, reducing symptoms, and allowing effective palliation, with a great improvement in quality of life. (orig.)

  14. Percutaneous peritoneovenous shunt positioning: technique and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Orsi, Franco; Grasso, Rosario Francesco; Bonomo, Guido; Marinucci, Irene [Division of Radiology, European Institute of Oncology, Milan (Italy); Monti, Cinzia [Institute of Radiology, University of Milan (Italy); Bellomi, Massimo [Division of Radiology, European Institute of Oncology, Milan (Italy); Institute of Radiology, University of Milan (Italy)

    2002-05-01

    Nine peritoneovenous shunts were positioned by percutaneous technique in seven patients with advanced malignancy causing severe refractory ascites, and in two patients with hepatic cirrhosis (one with hepatocarcinoma). In all patients the shunts were percutaneously placed through the subclavian vein in the angiographic suite under digital fluoroscopic guide. No complications directly related to the procedure occurred. The shunt was successfully positioned in all patients in 60 min average time. No patient showed symptoms related to pulmonary overload or to disseminated intravascular coagulation. All patients had a significant improvement of the objective symptoms related to ascites such as respiratory symptoms, dyspepsia, and functional impairment to evacuation describing an improvement of their quality of life. Maximum shunt patency was 273 days. Percutaneous placement of peritoneovenous shunt is a safe, fast, and inexpensive procedure, extremely useful in resolution of refractory ascites, reducing symptoms, and allowing effective palliation, with a great improvement in quality of life. (orig.)

  15. Sensitivity analysis technique for application to deterministic models

    International Nuclear Information System (INIS)

    Ishigami, T.; Cazzoli, E.; Khatib-Rahbar, M.; Unwin, S.D.

    1987-01-01

    The characterization of sever accident source terms for light water reactors should include consideration of uncertainties. An important element of any uncertainty analysis is an evaluation of the sensitivity of the output probability distributions reflecting source term uncertainties to assumptions regarding the input probability distributions. Historically, response surface methods (RSMs) were developed to replace physical models using, for example, regression techniques, with simplified models for example, regression techniques, with simplified models for extensive calculations. The purpose of this paper is to present a new method for sensitivity analysis that does not utilize RSM, but instead relies directly on the results obtained from the original computer code calculations. The merits of this approach are demonstrated by application of the proposed method to the suppression pool aerosol removal code (SPARC), and the results are compared with those obtained by sensitivity analysis with (a) the code itself, (b) a regression model, and (c) Iman's method

  16. Selection of productivity improvement techniques via mathematical modeling

    Directory of Open Access Journals (Sweden)

    Mahassan M. Khater

    2011-07-01

    Full Text Available This paper presents a new mathematical model to select an optimal combination of productivity improvement techniques. The proposed model of this paper considers four-stage cycle productivity and the productivity is assumed to be a linear function of fifty four improvement techniques. The proposed model of this paper is implemented for a real-world case study of manufacturing plant. The resulted problem is formulated as a mixed integer programming which can be solved for optimality using traditional methods. The preliminary results of the implementation of the proposed model of this paper indicate that the productivity can be improved through a change on equipments and it can be easily applied for both manufacturing and service industries.

  17. Materials and techniques for model construction

    Science.gov (United States)

    Wigley, D. A.

    1985-01-01

    The problems confronting the designer of models for cryogenic wind tunnel models are discussed with particular reference to the difficulties in obtaining appropriate data on the mechanical and physical properties of candidate materials and their fabrication technologies. The relationship between strength and toughness of alloys is discussed in the context of maximizing both and avoiding the problem of dimensional and microstructural instability. All major classes of materials used in model construction are considered in some detail and in the Appendix selected numerical data is given for the most relevant materials. The stepped-specimen program to investigate stress-induced dimensional changes in alloys is discussed in detail together with interpretation of the initial results. The methods used to bond model components are considered with particular reference to the selection of filler alloys and temperature cycles to avoid microstructural degradation and loss of mechanical properties.

  18. A Method to Test Model Calibration Techniques: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Judkoff, Ron; Polly, Ben; Neymark, Joel

    2016-09-01

    This paper describes a method for testing model calibration techniques. Calibration is commonly used in conjunction with energy retrofit audit models. An audit is conducted to gather information about the building needed to assemble an input file for a building energy modeling tool. A calibration technique is used to reconcile model predictions with utility data, and then the 'calibrated model' is used to predict energy savings from a variety of retrofit measures and combinations thereof. Current standards and guidelines such as BPI-2400 and ASHRAE-14 set criteria for 'goodness of fit' and assume that if the criteria are met, then the calibration technique is acceptable. While it is logical to use the actual performance data of the building to tune the model, it is not certain that a good fit will result in a model that better predicts post-retrofit energy savings. Therefore, the basic idea here is that the simulation program (intended for use with the calibration technique) is used to generate surrogate utility bill data and retrofit energy savings data against which the calibration technique can be tested. This provides three figures of merit for testing a calibration technique, 1) accuracy of the post-retrofit energy savings prediction, 2) closure on the 'true' input parameter values, and 3) goodness of fit to the utility bill data. The paper will also discuss the pros and cons of using this synthetic surrogate data approach versus trying to use real data sets of actual buildings.

  19. Carotid angioplasty and stenting under protection. Techniques, results and limitations.

    Science.gov (United States)

    Henry, M; Polydorou, A; Henry, I; Anagnostopoulou, I S; Polydorou, I A; Hugel, M

    2006-10-01

    A carotid stenosis is responsible for about 30% of strokes occurring. Carotid endarterectomy (CEA) is considered to be the gold standard treatment of a carotid stenosis. Carotid angioplasty and stenting (CAS) is emerging as a new alternative treatment for a carotid artery stenosis, but the risk of neurological complications and brain embolism remains the major drawback to this procedure. Therefore, in order to reduce the risks, we need: 1) good indications, good patient and lesion selection; 2) correct techniques; 3) brain protection devices (cerebral protection devices should be routinely used and are mandatory for any procedure); 4) 3 types of protection devices are available, but filters are the most commonly used (all protection devices have limitations and cannot prevent from all embolic events; however, neurological complications can be reduced by 60%); 5) a good choice of the stent and correct implantation (all stents are not equivalent and have different geometrical effects); 6) pharmacological adjuncts; 7) a good team. Recent studies have shown that CAS has superior short-term outcomes than CEA in high surgical risk patients, but there are enough reported data to conclude that CAS is also not inferior to CEA in low-risk patients. CAS under protection is the standard of care and is maybe becoming the gold standard treatment of a carotid stenosis at least in some subgroups of patients.

  20. SLR and GPS spatial techniques in ITRF. Argentine results.

    Science.gov (United States)

    Actis, Eloy Vicente; Huang, Dongping; Márquez, Raúl; Adarvez, Sonia; Flores, Matías; Brizuela, Diego; Nievas, Jesica; Podestá, Ricardo; Pacheco, Ana M.; Rojas, Hernán Alvis; Yin, Zhiqiang; Li, Jinzeng; Han, Yanben; Liu, Weidong; Wang, Rui

    2012-08-01

    Along the late 30 years spatial geodetic techniques enable us to measure horizontal and vertical deformations of the Earth’s surface with a very high precision. Performing this task we made Satellite Laser Ranging (SLR), and Global Positioning System (GPS) observations in South America ILRS 7406 Station placed at Observatorio Astronómico Félix Aguilar (OAFA) in San Juan, Argentina, accomplishing a Cooperation Agreement between CAS - NAOC and OAFA - UNSJ. Trough LAGEOS II Satellite observations we obtain rectangular coordinates of San Juan ILRS Station in the Terrestrial Reference Frame (ITR 2000), standing out that Argentine Station data were included in the late arrangements ITRF given by International Earth Rotation and Reference System Service (IERS). Spatial and temporary variations of the epoch 2010 - 2011 were evaluated finding out remarkable displacements, of about a half meter, related with seismic events on the region. We confirm these deformations by means of GP S determinations referred to Permanent GPS Station placed nearby the SLR Station.

  1. Models and Techniques for Proving Data Structure Lower Bounds

    DEFF Research Database (Denmark)

    Larsen, Kasper Green

    In this dissertation, we present a number of new techniques and tools for proving lower bounds on the operational time of data structures. These techniques provide new lines of attack for proving lower bounds in both the cell probe model, the group model, the pointer machine model and the I...... bound of tutq = (lgd􀀀1 n). For ball range searching, we get a lower bound of tutq = (n1􀀀1=d). The highest previous lower bound proved in the group model does not exceed ((lg n= lg lg n)2) on the maximum of tu and tq. Finally, we present a new technique for proving lower bounds....../O-model. In all cases, we push the frontiers further by proving lower bounds higher than what could possibly be proved using previously known techniques. For the cell probe model, our results have the following consequences: The rst (lg n) query time lower bound for linear space static data structures...

  2. EFFECT OF FLEXIBILITY ON THE RESULTS OF DOLPHIN SWIMMING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Slađana Tošić

    2011-09-01

    Full Text Available In order to determine the impact of flexibility on the results in swimming, we conducted a study on a sample of 50 female patients aged 11-14 years of age who are in the training process in the swimming clubs „Nis 2005“ and „Sveti Nikola“ in Nis. The study is applied to 14 measuring instruments that were divided into three groups: Measuring instruments for the assessment of flexibility (11; Measuring instruments for assessing the results of swimming (1; Measuring instruments for evaluation of morphological characteristics (2. The regression analysis determined the impact of flexibility on the results in swimming. The regression analysis didn't confirmed the assumption that there is a statistically significant effect of flexibility variables on results in swimming for female swimmers

  3. New diagnostic technique for Zeeman-compensated atomic beam slowing: technique and results

    OpenAIRE

    Molenaar, P.A.; Straten, P. van der; Heideman, H.G.M.; Metcalf, H.

    1997-01-01

    We have developed a new diagnostic tool for the study of Zeeman-compensated slowing of an alkali atomic beam. Our time-of-flight technique measures the longitudinal veloc- ity distribution of the slowed atoms with a resolution below the Doppler limit of 30 cm/s. Furthermore, it can map the position and velocity distribution of atoms in either ground hyperfine level inside the solenoid without any devices inside the solenoid. The technique reveals the optical pumping ef- fects, and shows in de...

  4. Arthroscopic management of posterior instability: evolution of technique and results.

    Science.gov (United States)

    Savoie, Felix H; Holt, M Shaun; Field, Larry D; Ramsey, J Randall

    2008-04-01

    , and its attached superior glenohumeral ligament, the coracohumeral ligament, the inferior glenohumeral ligament complex, and the infraspinatus, in addition to the posterior labrum and capsule, allows excellent outcomes to be achieved with arthroscopic posterior reconstruction techniques. Level IV, therapeutic case series.

  5. New diagnostic technique for Zeeman-compensated atomic beam slowing: technique and results

    NARCIS (Netherlands)

    Molenaar, P.A.; Straten, P. van der; Heideman, H.G.M.; Metcalf, H.

    1997-01-01

    We have developed a new diagnostic tool for the study of Zeeman-compensated slowing of an alkali atomic beam. Our time-of-flight technique measures the longitudinal veloc- ity distribution of the slowed atoms with a resolution below the Doppler limit of 30 cm/s. Furthermore, it can map

  6. Survey on result promotion of the atomic force technique

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Masato; Okuno, Yumiko [Nikkei Research Inst. of Industry and Markets, Tokyo (Japan)

    1998-02-01

    By change of environment around research and development of atomic force, investigation has been recently executed not only on a theme directing a specific aim, but also on technical development considering some applications to the other field reflected by social needs. Therefore, an effective procedure and program capable of reflecting and promoting results of the atomic fore development to other industrial field were necessary. In this study, methods of evaluation and industrialization on study results of the atomic force were investigated. As a result, in order to promote the study results to other field, it was found to be important that some free reasons and concept engineering to mediate between developing and applying sides were to be present. In addition, it was suggested by some searches that a new atomic industry has a probability to be created by using potential energies such as heat, radiation, pulse, and so on. In this paper, evaluation on industrialization of the atomic force technical resources, and establishment of the industrialization program were described. (G.K.)

  7. Constructing canine carotid artery stenosis model by endovascular technique

    International Nuclear Information System (INIS)

    Cheng Guangsen; Liu Yizhi

    2005-01-01

    Objective: To establish a carotid artery stenosis model by endovascular technique suitable for neuro-interventional therapy. Methods: Twelve dogs were anesthetized, the unilateral segments of the carotid arteries' tunica media and intima were damaged by a corneous guiding wire of home made. Twenty-four carotid artery stenosis models were thus created. DSA examination was performed on postprocedural weeks 2, 4, 8, 10 to estimate the changes of those stenotic carotid arteries. Results: Twenty-four carotid artery stenosis models were successfully created in twelve dogs. Conclusions: Canine carotid artery stenosis models can be created with the endovascular method having variation of pathologic characters and hemodynamic changes similar to human being. It is useful for further research involving the new technique and new material for interventional treatment. (authors)

  8. Ear surgery techniques results on hearing threshold improvement

    Directory of Open Access Journals (Sweden)

    Farhad Mokhtarinejad

    2013-01-01

    Full Text Available Background: Bone conduction (BC threshold depression is not always by means of sensory neural hearing loss and sometimes it is an artifact caused by middle ear pathologies and ossicular chain problems. In this research, the influences of ear surgeries on bone conduction were evaluated. Materials and Methods: This study was conducted as a clinical trial study. The ear surgery performed on 83 patients classified in four categories: Stapedectomy, tympanomastoid surgery and ossicular reconstruction partially or totally; Partial Ossicular Replacement Prosthesis (PORP and Total Ossicular Replacement Prosthesis (TORP. Bone conduction thresholds assessed in frequencies of 250, 500, 1000, 2000 and 4000 Hz pre and post the surgery. Results: In stapedectomy group, the average of BC threshold in all frequencies improved approximately 6 dB in frequency of 2000 Hz. In tympanomastoid group, BC threshold in the frequency of 500, 1000 and 2000 Hz changed 4 dB (P-value < 0.05. Moreover, In the PORP group, 5 dB enhancement was seen in 1000 and 2000 Hz. In TORP group, the results confirmed that BC threshold improved in all frequencies especially at 4000 Hz about 6.5 dB. Conclusion: In according to results of this study, BC threshold shift was seen after several ear surgeries such as stapedectomy, tympanoplasty, PORP and TORP. The average of BC improvement was approximately 5 dB. It must be considered that BC depression might happen because of ossicular chain problems. Therefore; by resolving middle ear pathologies, the better BC threshold was obtained, the less hearing problems would be faced.

  9. Variances in the projections, resulting from CLIMEX, Boosted Regression Trees and Random Forests techniques

    Science.gov (United States)

    Shabani, Farzin; Kumar, Lalit; Solhjouy-fard, Samaneh

    2017-08-01

    The aim of this study was to have a comparative investigation and evaluation of the capabilities of correlative and mechanistic modeling processes, applied to the projection of future distributions of date palm in novel environments and to establish a method of minimizing uncertainty in the projections of differing techniques. The location of this study on a global scale is in Middle Eastern Countries. We compared the mechanistic model CLIMEX (CL) with the correlative models MaxEnt (MX), Boosted Regression Trees (BRT), and Random Forests (RF) to project current and future distributions of date palm ( Phoenix dactylifera L.). The Global Climate Model (GCM), the CSIRO-Mk3.0 (CS) using the A2 emissions scenario, was selected for making projections. Both indigenous and alien distribution data of the species were utilized in the modeling process. The common areas predicted by MX, BRT, RF, and CL from the CS GCM were extracted and compared to ascertain projection uncertainty levels of each individual technique. The common areas identified by all four modeling techniques were used to produce a map indicating suitable and unsuitable areas for date palm cultivation for Middle Eastern countries, for the present and the year 2100. The four different modeling approaches predict fairly different distributions. Projections from CL were more conservative than from MX. The BRT and RF were the most conservative methods in terms of projections for the current time. The combination of the final CL and MX projections for the present and 2100 provide higher certainty concerning those areas that will become highly suitable for future date palm cultivation. According to the four models, cold, hot, and wet stress, with differences on a regional basis, appears to be the major restrictions on future date palm distribution. The results demonstrate variances in the projections, resulting from different techniques. The assessment and interpretation of model projections requires reservations

  10. Transluminal coronary angioplasty (TCA) techniques, indications and results

    International Nuclear Information System (INIS)

    Kober, G.; Lang, H.; Vallbracht, C.; Bussmann, W.D.; Hopf, R.; Kunkel, B.; Kaltenbach, M.

    1985-01-01

    Transluminal coronary angioplasty (TCA) was introduced in 1977 for dilatation of coronary stenoses. From October 1977 to December 1984 1087 procedures have been performed in Frankfurt. The mean success rate was 77% with an increase from 58% to 84% since 1977. Recurrences were seen within the first year in 15% of the patients, which could be treated successfully in a high percentage with a second TCA. Emergency bypass operations were necessary in 5.2%. Four patients (fatality rate 0.37%) died as the consequence of the intervention. Within few years TCA has become an established procedure for myocardial revascularisation, with a high success rate. Major progress has been possible in the last few years due to technical developments, which are still going on. They may lead to further improvement of the results and enlargement of the indication for TCA. (orig.) [de

  11. New results and techniques in space radio astronomy.

    Science.gov (United States)

    Alexander, J. K.

    1971-01-01

    The methods and results of early space radioastronomy experiments are reviewed, with emphasis on the RAE 1 spacecraft which was designed specifically and exclusively for radio astronomical studies. The RAE 1 carries two gravity-gradient-stabilized 229-m traveling-wave V-antennas, a 37-m dipole antenna, and a number of radiometer systems to provide measurements over the 0.2 to 9.2 MHz frequency range with a time resolution of 0.5 sec and an absolute accuracy of plus or minus 25%. Observations of solar bursts at frequencies down to 0.2 MHz provide new information on the density, plasma velocity, and dynamics of coronal streamers out to distances greater than 50 solar radii. New information on the distribution of the ionized component of the interstellar medium is being obtained from galactic continuum background maps at frequencies around 4 MHz. Cosmic noise background spectra measured down to 0.5 MHz produce new estimates on the interstellar flux of cosmic rays, on magnetic fields in the galactic halo, and on distant extragalactic radio sources.

  12. Comparison of neptunium sorption results using batch and column techniques

    International Nuclear Information System (INIS)

    Triay, I.R.; Furlano, A.C.; Weaver, S.C.; Chipera, S.J.; Bish, D.L.

    1996-08-01

    We used crushed-rock columns to study the sorption retardation of neptunium by zeolitic, devitrified, and vitric tuffs typical of those at the site of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. We used two sodium bicarbonate waters (groundwater from Well J-13 at the site and water prepared to simulate groundwater from Well UE-25p No. 1) under oxidizing conditions. It was found that values of the sorption distribution coefficient, Kd, obtained from these column experiments under flowing conditions, regardless of the water or the water velocity used, agreed well with those obtained earlier from batch sorption experiments under static conditions. The batch sorption distribution coefficient can be used to predict the arrival time for neptunium eluted through the columns. On the other hand, the elution curves showed dispersivity, which implies that neptunium sorption in these tuffs may be nonlinear, irreversible, or noninstantaneous. As a result, use of a batch sorption distribution coefficient to calculate neptunium transport through Yucca Mountain tuffs would yield conservative values for neptunium release from the site. We also noted that neptunium (present as the anionic neptunyl carbonate complex) never eluted prior to tritiated water, which implies that charge exclusion does not appear to exclude neptunium from the tuff pores. The column experiments corroborated the trends observed in batch sorption experiments: neptunium sorption onto devitrified and vitric tuffs is minimal and sorption onto zeolitic tuffs decreases as the amount of sodium and bicarbonate/carbonate in the water increases

  13. Automated Techniques for the Qualitative Analysis of Ecological Models: Continuous Models

    Directory of Open Access Journals (Sweden)

    Lynn van Coller

    1997-06-01

    Full Text Available The mathematics required for a detailed analysis of the behavior of a model can be formidable. In this paper, I demonstrate how various computer packages can aid qualitative analyses by implementing techniques from dynamical systems theory. Because computer software is used to obtain the results, the techniques can be used by nonmathematicians as well as mathematicians. In-depth analyses of complicated models that were previously very difficult to study can now be done. Because the paper is intended as an introduction to applying the techniques to ecological models, I have included an appendix describing some of the ideas and terminology. A second appendix shows how the techniques can be applied to a fairly simple predator-prey model and establishes the reliability of the computer software. The main body of the paper discusses a ratio-dependent model. The new techniques highlight some limitations of isocline analyses in this three-dimensional setting and show that the model is structurally unstable. Another appendix describes a larger model of a sheep-pasture-hyrax-lynx system. Dynamical systems techniques are compared with a traditional sensitivity analysis and are found to give more information. As a result, an incomplete relationship in the model is highlighted. I also discuss the resilience of these models to both parameter and population perturbations.

  14. AN OVERVIEW OF REDUCED ORDER MODELING TECHNIQUES FOR SAFETY APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Mandelli, D.; Alfonsi, A.; Talbot, P.; Wang, C.; Maljovec, D.; Smith, C.; Rabiti, C.; Cogliati, J.

    2016-10-01

    The RISMC project is developing new advanced simulation-based tools to perform Computational Risk Analysis (CRA) for the existing fleet of U.S. nuclear power plants (NPPs). These tools numerically model not only the thermal-hydraulic behavior of the reactors primary and secondary systems, but also external event temporal evolution and component/system ageing. Thus, this is not only a multi-physics problem being addressed, but also a multi-scale problem (both spatial, µm-mm-m, and temporal, seconds-hours-years). As part of the RISMC CRA approach, a large amount of computationally-expensive simulation runs may be required. An important aspect is that even though computational power is growing, the overall computational cost of a RISMC analysis using brute-force methods may be not viable for certain cases. A solution that is being evaluated to assist the computational issue is the use of reduced order modeling techniques. During the FY2015, we investigated and applied reduced order modeling techniques to decrease the RISMC analysis computational cost by decreasing the number of simulation runs; for this analysis improvement we used surrogate models instead of the actual simulation codes. This article focuses on the use of reduced order modeling techniques that can be applied to RISMC analyses in order to generate, analyze, and visualize data. In particular, we focus on surrogate models that approximate the simulation results but in a much faster time (microseconds instead of hours/days).

  15. Structural modeling techniques by finite element method

    International Nuclear Information System (INIS)

    Kang, Yeong Jin; Kim, Geung Hwan; Ju, Gwan Jeong

    1991-01-01

    This book includes introduction table of contents chapter 1 finite element idealization introduction summary of the finite element method equilibrium and compatibility in the finite element solution degrees of freedom symmetry and anti symmetry modeling guidelines local analysis example references chapter 2 static analysis structural geometry finite element models analysis procedure modeling guidelines references chapter 3 dynamic analysis models for dynamic analysis dynamic analysis procedures modeling guidelines and modeling guidelines.

  16. Results of the naive quark model

    International Nuclear Information System (INIS)

    Gignoux, C.

    1987-10-01

    The hypotheses and limits of the naive quark model are recalled and results on nucleon-nucleon scattering and possible multiquark states are presented. Results show that with this model, ropers do not come. For hadron-hadron interactions, the model predicts Van der Waals forces that the resonance group method does not allow. Known many-body forces are not found in the model. The lack of mesons shows up in the absence of a far reaching force. However, the model does have strengths. It is free from spuriousness of center of mass, and allows a democratic handling of flavor. It has few parameters, and its predictions are very good [fr

  17. Skin fluorescence model based on the Monte Carlo technique

    Science.gov (United States)

    Churmakov, Dmitry Y.; Meglinski, Igor V.; Piletsky, Sergey A.; Greenhalgh, Douglas A.

    2003-10-01

    The novel Monte Carlo technique of simulation of spatial fluorescence distribution within the human skin is presented. The computational model of skin takes into account spatial distribution of fluorophores following the collagen fibers packing, whereas in epidermis and stratum corneum the distribution of fluorophores assumed to be homogeneous. The results of simulation suggest that distribution of auto-fluorescence is significantly suppressed in the NIR spectral region, while fluorescence of sensor layer embedded in epidermis is localized at the adjusted depth. The model is also able to simulate the skin fluorescence spectra.

  18. Application of object modeling technique to medical image retrieval system

    International Nuclear Information System (INIS)

    Teshima, Fumiaki; Abe, Takeshi

    1993-01-01

    This report describes the results of discussions on the object-oriented analysis methodology, which is one of the object-oriented paradigms. In particular, we considered application of the object modeling technique (OMT) to the analysis of a medical image retrieval system. The object-oriented methodology places emphasis on the construction of an abstract model from real-world entities. The effectiveness of and future improvements to OMT are discussed from the standpoint of the system's expandability. These discussions have elucidated that the methodology is sufficiently well-organized and practical to be applied to commercial products, provided that it is applied to the appropriate problem domain. (author)

  19. Construct canine intracranial aneurysm model by endovascular technique

    International Nuclear Information System (INIS)

    Liang Xiaodong; Liu Yizhi; Ni Caifang; Ding Yi

    2004-01-01

    Objective: To construct canine bifurcation aneurysms suitable for evaluating the exploration of endovascular devices for interventional therapy by endovascular technique. Methods: The right common carotid artery of six dogs was expanded with a pliable balloon by means of endovascular technique, then embolization with detached balloon was taken at their originations DAS examination were performed on 1, 2, 3 d after the procedurse. Results: 6 aneurysm models were created in six dogs successfully with the mean width and height of the aneurysms decreasing in 3 days. Conclusions: This canine aneurysm model presents the virtue in the size and shape of human cerebral bifurcation saccular aneurysms on DSA image, suitable for developing the exploration of endovascular devices for aneurismal therapy. The procedure is quick, reliable and reproducible. (authors)

  20. Interpreting Results from the Multinomial Logit Model

    DEFF Research Database (Denmark)

    Wulff, Jesper

    2015-01-01

    This article provides guidelines and illustrates practical steps necessary for an analysis of results from the multinomial logit model (MLM). The MLM is a popular model in the strategy literature because it allows researchers to examine strategic choices with multiple outcomes. However, there see...... suitable for both interpretation and communication of results. The pratical steps are illustrated through an application of the MLM to the choice of foreign market entry mode.......This article provides guidelines and illustrates practical steps necessary for an analysis of results from the multinomial logit model (MLM). The MLM is a popular model in the strategy literature because it allows researchers to examine strategic choices with multiple outcomes. However, there seem...... to be systematic issues with regard to how researchers interpret their results when using the MLM. In this study, I present a set of guidelines critical to analyzing and interpreting results from the MLM. The procedure involves intuitive graphical representations of predicted probabilities and marginal effects...

  1. Prediction of high level vibration test results by use of available inelastic analysis techniques

    International Nuclear Information System (INIS)

    Hofmayer, C.H.; Park, Y.J.; Costello, J.F.

    1991-01-01

    As part of a cooperative study between the United States and Japan, the US Nuclear Regulatory Commission and the Ministry of International Trade and Industry of Japan agreed to perform a test program that would subject a large scale piping model to significant plastic strains under excitation conditions much greater than the design condition for nuclear power plants. The objective was to compare the results of the tests with state-of-the-art analyses. Comparisons were done at different excitation levels from elastic to elastic-plastic to levels where cracking was induced in the test model. The program was called the high Level Vibration Test (HLVT). The HLVT was performed on the seismic table at the Tadotsu Engineering Laboratory of Nuclear Power Engineering Test Center in Japan. The test model was constructed by modifying the 1/2.5 scale model of one loop of a PWR primary coolant system which was previously tested by NUPEC as part of their seismic proving test program. A comparison of various analysis techniques with test results shows a higher prediction error in the detailed strain values than in the overall response values. This prediction error is magnified as the plasticity in the test model increases. There is no significant difference in the peak responses between the simplified and the detailed analyses. A comparison between various detailed finite element model runs indicates that the material properties and plasticity modeling have a significant impact on the plastic strain responses under dynamic loading reversals. 5 refs., 12 figs

  2. Modeling Techniques for a Computational Efficient Dynamic Turbofan Engine Model

    Directory of Open Access Journals (Sweden)

    Rory A. Roberts

    2014-01-01

    Full Text Available A transient two-stream engine model has been developed. Individual component models developed exclusively in MATLAB/Simulink including the fan, high pressure compressor, combustor, high pressure turbine, low pressure turbine, plenum volumes, and exit nozzle have been combined to investigate the behavior of a turbofan two-stream engine. Special attention has been paid to the development of transient capabilities throughout the model, increasing physics model, eliminating algebraic constraints, and reducing simulation time through enabling the use of advanced numerical solvers. The lessening of computation time is paramount for conducting future aircraft system-level design trade studies and optimization. The new engine model is simulated for a fuel perturbation and a specified mission while tracking critical parameters. These results, as well as the simulation times, are presented. The new approach significantly reduces the simulation time.

  3. Level-set techniques for facies identification in reservoir modeling

    Science.gov (United States)

    Iglesias, Marco A.; McLaughlin, Dennis

    2011-03-01

    In this paper we investigate the application of level-set techniques for facies identification in reservoir models. The identification of facies is a geometrical inverse ill-posed problem that we formulate in terms of shape optimization. The goal is to find a region (a geologic facies) that minimizes the misfit between predicted and measured data from an oil-water reservoir. In order to address the shape optimization problem, we present a novel application of the level-set iterative framework developed by Burger in (2002 Interfaces Free Bound. 5 301-29 2004 Inverse Problems 20 259-82) for inverse obstacle problems. The optimization is constrained by (the reservoir model) a nonlinear large-scale system of PDEs that describes the reservoir dynamics. We reformulate this reservoir model in a weak (integral) form whose shape derivative can be formally computed from standard results of shape calculus. At each iteration of the scheme, the current estimate of the shape derivative is utilized to define a velocity in the level-set equation. The proper selection of this velocity ensures that the new shape decreases the cost functional. We present results of facies identification where the velocity is computed with the gradient-based (GB) approach of Burger (2002) and the Levenberg-Marquardt (LM) technique of Burger (2004). While an adjoint formulation allows the straightforward application of the GB approach, the LM technique requires the computation of the large-scale Karush-Kuhn-Tucker system that arises at each iteration of the scheme. We efficiently solve this system by means of the representer method. We present some synthetic experiments to show and compare the capabilities and limitations of the proposed implementations of level-set techniques for the identification of geologic facies.

  4. Level-set techniques for facies identification in reservoir modeling

    International Nuclear Information System (INIS)

    Iglesias, Marco A; McLaughlin, Dennis

    2011-01-01

    In this paper we investigate the application of level-set techniques for facies identification in reservoir models. The identification of facies is a geometrical inverse ill-posed problem that we formulate in terms of shape optimization. The goal is to find a region (a geologic facies) that minimizes the misfit between predicted and measured data from an oil–water reservoir. In order to address the shape optimization problem, we present a novel application of the level-set iterative framework developed by Burger in (2002 Interfaces Free Bound. 5 301–29; 2004 Inverse Problems 20 259–82) for inverse obstacle problems. The optimization is constrained by (the reservoir model) a nonlinear large-scale system of PDEs that describes the reservoir dynamics. We reformulate this reservoir model in a weak (integral) form whose shape derivative can be formally computed from standard results of shape calculus. At each iteration of the scheme, the current estimate of the shape derivative is utilized to define a velocity in the level-set equation. The proper selection of this velocity ensures that the new shape decreases the cost functional. We present results of facies identification where the velocity is computed with the gradient-based (GB) approach of Burger (2002) and the Levenberg–Marquardt (LM) technique of Burger (2004). While an adjoint formulation allows the straightforward application of the GB approach, the LM technique requires the computation of the large-scale Karush–Kuhn–Tucker system that arises at each iteration of the scheme. We efficiently solve this system by means of the representer method. We present some synthetic experiments to show and compare the capabilities and limitations of the proposed implementations of level-set techniques for the identification of geologic facies

  5. Moving objects management models, techniques and applications

    CERN Document Server

    Meng, Xiaofeng; Xu, Jiajie

    2014-01-01

    This book describes the topics of moving objects modeling and location tracking, indexing and querying, clustering, location uncertainty, traffic aware navigation and privacy issues as well as the application to intelligent transportation systems.

  6. Enhancing photogrammetric 3d city models with procedural modeling techniques for urban planning support

    International Nuclear Information System (INIS)

    Schubiger-Banz, S; Arisona, S M; Zhong, C

    2014-01-01

    This paper presents a workflow to increase the level of detail of reality-based 3D urban models. It combines the established workflows from photogrammetry and procedural modeling in order to exploit distinct advantages of both approaches. The combination has advantages over purely automatic acquisition in terms of visual quality, accuracy and model semantics. Compared to manual modeling, procedural techniques can be much more time effective while maintaining the qualitative properties of the modeled environment. In addition, our method includes processes for procedurally adding additional features such as road and rail networks. The resulting models meet the increasing needs in urban environments for planning, inventory, and analysis

  7. Results of hip arthroplasty using Paavilainen technique in patients with congenitally dislocated hip

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2014-01-01

    Full Text Available The purpose of the study was to analyze the medium- and long-term results of hip arthroplasty using Paavilainen technique in patients with the congenitally dislocated hip. Methods: From 2001 to 2012 180 operations were carried out were using the Paavilainen technique in 140 patients with high dislocation of the hip (Crowe IV. All patients were clinically evaluated using the Harris Hip Score (HHS, VAS and radiography. Statistical analysis was performed using the Pearson correlation coefficients, multiple regression analysis and classification trees analysis. Results: The average Harris score improved from preoperative 41.6 (40,3-43,5 to 79.3 (77,9-82,7 at final follow-up, and the difference was significant. Early complications were 9% (the most frequent were fractures of the proximal femur, later - 16.7% (pseudoarthrosis of the greater trochanter, 13.9%; disclocations-1,1%, aseptic loosening of the components - 1.7%, reoperation performed in 8.3% of cases. Such factors as age and limb length has statistically significant effect on functional outcomes. Established predictive model allows to get the best possible functional outcome in such patients with severe dysplasia. Conclusions: Total Hip arthroplasty using the Paavilainen technique is an effective method of surgical treatment in patients with the congenitally dislocated hip, but it is technically difficult operation with a high incidence of complications in comparison with standard primary total hip replacement.

  8. Results of steel containment vessel model test

    International Nuclear Information System (INIS)

    Luk, V.K.; Ludwigsen, J.S.; Hessheimer, M.F.; Komine, Kuniaki; Matsumoto, Tomoyuki; Costello, J.F.

    1998-05-01

    A series of static overpressurization tests of scale models of nuclear containment structures is being conducted by Sandia National Laboratories for the Nuclear Power Engineering Corporation of Japan and the US Nuclear Regulatory Commission. Two tests are being conducted: (1) a test of a model of a steel containment vessel (SCV) and (2) a test of a model of a prestressed concrete containment vessel (PCCV). This paper summarizes the conduct of the high pressure pneumatic test of the SCV model and the results of that test. Results of this test are summarized and are compared with pretest predictions performed by the sponsoring organizations and others who participated in a blind pretest prediction effort. Questions raised by this comparison are identified and plans for posttest analysis are discussed

  9. Model measurements for new accelerating techniques

    International Nuclear Information System (INIS)

    Aronson, S.; Haseroth, H.; Knott, J.; Willis, W.

    1988-06-01

    We summarize the work carried out for the past two years, concerning some different ways for achieving high-field gradients, particularly in view of future linear lepton colliders. These studies and measurements on low power models concern the switched power principle and multifrequency excitation of resonant cavities. 15 refs., 12 figs

  10. Numerical and modeling techniques used in the EPIC code

    International Nuclear Information System (INIS)

    Pizzica, P.A.; Abramson, P.B.

    1977-01-01

    EPIC models fuel and coolant motion which result from internal fuel pin pressure (from fission gas or fuel vapor) and/or from the generation of sodium vapor pressures in the coolant channel subsequent to pin failure in an LMFBR. The modeling includes the ejection of molten fuel from the pin into a coolant channel with any amount of voiding through a clad rip which may be of any length or which may expand with time. One-dimensional Eulerian hydrodynamics is used to model both the motion of fuel and fission gas inside a molten fuel cavity and the mixture of two-phase sodium and fission gas in the channel. Motion of molten fuel particles in the coolant channel is tracked with a particle-in-cell technique

  11. Soft computing techniques toward modeling the water supplies of Cyprus.

    Science.gov (United States)

    Iliadis, L; Maris, F; Tachos, S

    2011-10-01

    This research effort aims in the application of soft computing techniques toward water resources management. More specifically, the target is the development of reliable soft computing models capable of estimating the water supply for the case of "Germasogeia" mountainous watersheds in Cyprus. Initially, ε-Regression Support Vector Machines (ε-RSVM) and fuzzy weighted ε-RSVMR models have been developed that accept five input parameters. At the same time, reliable artificial neural networks have been developed to perform the same job. The 5-fold cross validation approach has been employed in order to eliminate bad local behaviors and to produce a more representative training data set. Thus, the fuzzy weighted Support Vector Regression (SVR) combined with the fuzzy partition has been employed in an effort to enhance the quality of the results. Several rational and reliable models have been produced that can enhance the efficiency of water policy designers. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. [Hierarchy structuring for mammography technique by interpretive structural modeling method].

    Science.gov (United States)

    Kudo, Nozomi; Kurowarabi, Kunio; Terashita, Takayoshi; Nishimoto, Naoki; Ogasawara, Katsuhiko

    2009-10-20

    Participation in screening mammography is currently desired in Japan because of the increase in breast cancer morbidity. However, the pain and discomfort of mammography is recognized as a significant deterrent for women considering this examination. Thus quick procedures, sufficient experience, and advanced skills are required for radiologic technologists. The aim of this study was to make the point of imaging techniques explicit and to help understand the complicated procedure. We interviewed 3 technologists who were highly skilled in mammography, and 14 factors were retrieved by using brainstorming and the KJ method. We then applied Interpretive Structural Modeling (ISM) to the factors and developed a hierarchical concept structure. The result showed a six-layer hierarchy whose top node was explanation of the entire procedure on mammography. Male technologists were related to as a negative factor. Factors concerned with explanation were at the upper node. We gave attention to X-ray techniques and considerations. The findings will help beginners improve their skills.

  13. The EURAD model: Design and first results

    International Nuclear Information System (INIS)

    1989-01-01

    The contributions are abridged versions of lectures delivered on the occasion of the presentation meeting of the EURAD project on the 20th and 21st of February 1989 in Cologne. EURAD stands for European Acid Deposition Model. The project takes one of the possible and necessary ways to search for scientific answers to the questions which the modifications of the atmosphere caused by anthropogenic influence raise. One of the objectives is to develop a realistic numeric model of long-distance transport of harmful substances in the troposphere over Europe and to use this model for the investigation of pollutant distribution but also for the support of their experimental study. The EURAD Model consists of two parts: a meteorologic mesoscale model and a chemical transport model. In the first part of the presentation, these parts are introduced and questions concerning the implementation of the entire model on the computer system CRAY X-MP/22 discussed. Afterwards it is reported upon the results of the test calculations for the cases 'Chernobyl' and 'Alpex'. Thereafter selected problems concerning the treatments of meteorological and air-chemistry processes as well as the parametrization of subscale processes within the model are discussed. The conclusion is made by two lectures upon emission evaluations and emission scenarios. (orig./KW) [de

  14. A new cerebral vasospasm model established with endovascular puncture technique

    International Nuclear Information System (INIS)

    Tu Jianfei; Liu Yizhi; Ji Jiansong; Zhao Zhongwei

    2011-01-01

    Objective: To investigate the method of establishing cerebral vasospasm (CVS) models in rabbits by using endovascular puncture technique. Methods: Endovascular puncture procedure was performed in 78 New Zealand white rabbits to produce subarachnoid hemorrhage (SAH). The survival rabbits were randomly divided into seven groups (3 h, 12 h, 1 d, 2 d, 3 d, 7 d and 14 d), with five rabbits in each group for both study group (SAH group) and control group. Cerebral CT scanning was carried out in all rabbits both before and after the operation. The inner diameter and the thickness of vascular wall of both posterior communicating artery (PcoA) and basilar artery (BA) were determined after the animals were sacrificed, and the results were analyzed. Results: Of 78 experimental rabbits, CVS model was successfully established in 45, including 35 of SAH group and 10 control subgroup. The technical success rate was 57.7%. Twelve hours after the procedure, the inner diameter of PcoA and BA in SAH group was decreased by 45.6% and 52.3%, respectively, when compared with these in control group. The vascular narrowing showed biphasic changes, the inner diameter markedly decreased again at the 7th day when the decrease reached its peak to 31.2% and 48.6%, respectively. Conclusion: Endovascular puncture technique is an effective method to establish CVS models in rabbits. The death rate of experimental animals can be decreased if new interventional material is used and the manipulation is carefully performed. (authors)

  15. A physiological production model for cacao : results of model simulations

    NARCIS (Netherlands)

    Zuidema, P.A.; Leffelaar, P.A.

    2002-01-01

    CASE2 is a physiological model for cocoa (Theobroma cacao L.) growth and yield. This report introduces the CAcao Simulation Engine for water-limited production in a non-technical way and presents simulation results obtained with the model.

  16. A probabilistic evaluation procedure for process model matching techniques

    NARCIS (Netherlands)

    Kuss, Elena; Leopold, Henrik; van der Aa, Han; Stuckenschmidt, Heiner; Reijers, Hajo A.

    2018-01-01

    Process model matching refers to the automatic identification of corresponding activities between two process models. It represents the basis for many advanced process model analysis techniques such as the identification of similar process parts or process model search. A central problem is how to

  17. Modelling rainfall erosion resulting from climate change

    Science.gov (United States)

    Kinnell, Peter

    2016-04-01

    It is well known that soil erosion leads to agricultural productivity decline and contributes to water quality decline. The current widely used models for determining soil erosion for management purposes in agriculture focus on long term (~20 years) average annual soil loss and are not well suited to determining variations that occur over short timespans and as a result of climate change. Soil loss resulting from rainfall erosion is directly dependent on the product of runoff and sediment concentration both of which are likely to be influenced by climate change. This presentation demonstrates the capacity of models like the USLE, USLE-M and WEPP to predict variations in runoff and erosion associated with rainfall events eroding bare fallow plots in the USA with a view to modelling rainfall erosion in areas subject to climate change.

  18. INTRAVAL test case 1b - modelling results

    International Nuclear Information System (INIS)

    Jakob, A.; Hadermann, J.

    1991-07-01

    This report presents results obtained within Phase I of the INTRAVAL study. Six different models are fitted to the results of four infiltration experiments with 233 U tracer on small samples of crystalline bore cores originating from deep drillings in Northern Switzerland. Four of these are dual porosity media models taking into account advection and dispersion in water conducting zones (either tubelike veins or planar fractures), matrix diffusion out of these into pores of the solid phase, and either non-linear or linear sorption of the tracer onto inner surfaces. The remaining two are equivalent porous media models (excluding matrix diffusion) including either non-linear sorption onto surfaces of a single fissure family or linear sorption onto surfaces of several different fissure families. The fits to the experimental data have been carried out by Marquardt-Levenberg procedure yielding error estimates of the parameters, correlation coefficients and also, as a measure for the goodness of the fits, the minimum values of the χ 2 merit function. The effects of different upstream boundary conditions are demonstrated and the penetration depth for matrix diffusion is discussed briefly for both alternative flow path scenarios. The calculations show that the dual porosity media models are significantly more appropriate to the experimental data than the single porosity media concepts. Moreover, it is matrix diffusion rather than the non-linearity of the sorption isotherm which is responsible for the tailing part of the break-through curves. The extracted parameter values for some models for both the linear and non-linear (Freundlich) sorption isotherms are consistent with the results of independent static batch sorption experiments. From the fits, it is generally not possible to discriminate between the two alternative flow path geometries. On the basis of the modelling results, some proposals for further experiments are presented. (author) 15 refs., 23 figs., 7 tabs

  19. Model order reduction techniques with applications in finite element analysis

    CERN Document Server

    Qu, Zu-Qing

    2004-01-01

    Despite the continued rapid advance in computing speed and memory the increase in the complexity of models used by engineers persists in outpacing them. Even where there is access to the latest hardware, simulations are often extremely computationally intensive and time-consuming when full-blown models are under consideration. The need to reduce the computational cost involved when dealing with high-order/many-degree-of-freedom models can be offset by adroit computation. In this light, model-reduction methods have become a major goal of simulation and modeling research. Model reduction can also ameliorate problems in the correlation of widely used finite-element analyses and test analysis models produced by excessive system complexity. Model Order Reduction Techniques explains and compares such methods focusing mainly on recent work in dynamic condensation techniques: - Compares the effectiveness of static, exact, dynamic, SEREP and iterative-dynamic condensation techniques in producing valid reduced-order mo...

  20. Use of advanced modeling techniques to optimize thermal packaging designs.

    Science.gov (United States)

    Formato, Richard M; Potami, Raffaele; Ahmed, Iftekhar

    2010-01-01

    Through a detailed case study the authors demonstrate, for the first time, the capability of using advanced modeling techniques to correctly simulate the transient temperature response of a convective flow-based thermal shipper design. The objective of this case study was to demonstrate that simulation could be utilized to design a 2-inch-wall polyurethane (PUR) shipper to hold its product box temperature between 2 and 8 °C over the prescribed 96-h summer profile (product box is the portion of the shipper that is occupied by the payload). Results obtained from numerical simulation are in excellent agreement with empirical chamber data (within ±1 °C at all times), and geometrical locations of simulation maximum and minimum temperature match well with the corresponding chamber temperature measurements. Furthermore, a control simulation test case was run (results taken from identical product box locations) to compare the coupled conduction-convection model with a conduction-only model, which to date has been the state-of-the-art method. For the conduction-only simulation, all fluid elements were replaced with "solid" elements of identical size and assigned thermal properties of air. While results from the coupled thermal/fluid model closely correlated with the empirical data (±1 °C), the conduction-only model was unable to correctly capture the payload temperature trends, showing a sizeable error compared to empirical values (ΔT > 6 °C). A modeling technique capable of correctly capturing the thermal behavior of passively refrigerated shippers can be used to quickly evaluate and optimize new packaging designs. Such a capability provides a means to reduce the cost and required design time of shippers while simultaneously improving their performance. Another advantage comes from using thermal modeling (assuming a validated model is available) to predict the temperature distribution in a shipper that is exposed to ambient temperatures which were not bracketed

  1. Transvaginal Cystocele Repair by Purse-String Technique Reinforced with Three Simple Sutures: Surgical Technique and Results

    Directory of Open Access Journals (Sweden)

    Ho-Sook Song

    2012-09-01

    Full Text Available Purpose Different techniques for cystocele repair including the conventional anterior colporrhaphy and mesh technique are known. Our goal was to evaluate the anatomical success and safety of our method of transvaginal anterior vaginal wall repair by the purse-string technique reinforced with three simple additional sutures in the repair of cystocele over a 4-year follow-up period. Methods This was a retrospective review of 69 consecutive patients (grades 2 to 4 who underwent the above operations between 2001 and 2011, including their success rates as assessed by use of the Baden-Walker halfway classification system. Results Of the patients, 62 patients (98% were completely cured of cystocele and 1 patient showed grade 2 cystocele recurrence that required no further treatment. Two patients with grade 4 cystocele were completely cured. There was no vaginal erosion related to the cystocele repair. Conclusions Transvaginal anterior colporrhaphy by a purse-string technique reinforced with simple additive sutures appears to be a simple, safe, and easily performed approach in cystocele repair. There is no need for other material for reinforcement, even in high-grade cystocele, which is an advantage of our technique.

  2. EXCHANGE-RATES FORECASTING: EXPONENTIAL SMOOTHING TECHNIQUES AND ARIMA MODELS

    Directory of Open Access Journals (Sweden)

    Dezsi Eva

    2011-07-01

    Full Text Available Exchange rates forecasting is, and has been a challenging task in finance. Statistical and econometrical models are widely used in analysis and forecasting of foreign exchange rates. This paper investigates the behavior of daily exchange rates of the Romanian Leu against the Euro, United States Dollar, British Pound, Japanese Yen, Chinese Renminbi and the Russian Ruble. Smoothing techniques are generated and compared with each other. These models include the Simple Exponential Smoothing technique, as the Double Exponential Smoothing technique, the Simple Holt-Winters, the Additive Holt-Winters, namely the Autoregressive Integrated Moving Average model.

  3. On a Graphical Technique for Evaluating Some Rational Expectations Models

    DEFF Research Database (Denmark)

    Johansen, Søren; Swensen, Anders R.

    2011-01-01

    Campbell and Shiller (1987) proposed a graphical technique for the present value model, which consists of plotting estimates of the spread and theoretical spread as calculated from the cointegrated vector autoregressive model without imposing the restrictions implied by the present value model....... In addition to getting a visual impression of the fit of the model, the purpose is to see if the two spreads are nevertheless similar as measured by correlation, variance ratio, and noise ratio. We extend these techniques to a number of rational expectation models and give a general definition of spread...

  4. ADVANCED TECHNIQUES FOR RESERVOIR SIMULATION AND MODELING OF NONCONVENTIONAL WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Louis J. Durlofsky; Khalid Aziz

    2004-08-20

    in the wellbore); and (3) accurate approaches to account for the effects of reservoir heterogeneity and for the optimization of nonconventional well deployment. An overview of our progress in each of these main areas is as follows. A general purpose object-oriented research simulator (GPRS) was developed under this project. The GPRS code is managed using modern software management techniques and has been deployed to many companies and research institutions. The simulator includes general black-oil and compositional modeling modules. The formulation is general in that it allows for the selection of a wide variety of primary and secondary variables and accommodates varying degrees of solution implicitness. Specifically, we developed and implemented an IMPSAT procedure (implicit in pressure and saturation, explicit in all other variables) for compositional modeling as well as an adaptive implicit procedure. Both of these capabilities allow for efficiency gains through selective implicitness. The code treats cell connections through a general connection list, which allows it to accommodate both structured and unstructured grids. The GPRS code was written to be easily extendable so new modeling techniques can be readily incorporated. Along these lines, we developed a new dual porosity module compatible with the GPRS framework, as well as a new discrete fracture model applicable for fractured or faulted reservoirs. Both of these methods display substantial advantages over previous implementations. Further, we assessed the performance of different preconditioners in an attempt to improve the efficiency of the linear solver. As a result of this investigation, substantial improvements in solver performance were achieved.

  5. Virtual 3d City Modeling: Techniques and Applications

    Science.gov (United States)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2013-08-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as Building, Tree, Vegetation, and some manmade feature belonging to urban area. There are various terms used for 3D city models such as "Cybertown", "Cybercity", "Virtual City", or "Digital City". 3D city models are basically a computerized or digital model of a city contains the graphic representation of buildings and other objects in 2.5 or 3D. Generally three main Geomatics approach are using for Virtual 3-D City models generation, in first approach, researcher are using Conventional techniques such as Vector Map data, DEM, Aerial images, second approach are based on High resolution satellite images with LASER scanning, In third method, many researcher are using Terrestrial images by using Close Range Photogrammetry with DSM & Texture mapping. We start this paper from the introduction of various Geomatics techniques for 3D City modeling. These techniques divided in to two main categories: one is based on Automation (Automatic, Semi-automatic and Manual methods), and another is Based on Data input techniques (one is Photogrammetry, another is Laser Techniques). After details study of this, finally in short, we are trying to give the conclusions of this study. In the last, we are trying to give the conclusions of this research paper and also giving a short view for justification and analysis, and present trend for 3D City modeling. This paper gives an overview about the Techniques related with "Generation of Virtual 3-D City models using Geomatics Techniques" and the Applications of Virtual 3D City models. Photogrammetry, (Close range, Aerial, Satellite), Lasergrammetry, GPS, or combination of these modern Geomatics techniques play a major role to create a virtual 3-D City model. Each and every techniques and method has some advantages and some drawbacks. Point cloud model is a modern trend for virtual 3-D city model. Photo-realistic, Scalable, Geo-referenced virtual 3

  6. Discussion of gas trade model (GTM) results

    International Nuclear Information System (INIS)

    Manne, A.

    1989-01-01

    This is in response to your invitation to comment on the structure of GTM and also upon the differences between its results and those of other models participating in EMF9. First a word upon the structure. GTM was originally designed to provide both regional and sectoral detail within the North American market for natural gas at a single point in time, e.g. the year 2000. It is a spatial equilibrium model in which a solution is obtained by maximizing a nonlinear function, the sum of consumers and producers surplus. Since transport costs are included in producers cost, this formulation automatically ensures that geographical price differentials will not differ by more than transport costs. For purposes of EMF9, GTM was modified to allow for resource development and depletion over time

  7. The Danish national passenger modelModel specification and results

    DEFF Research Database (Denmark)

    Rich, Jeppe; Hansen, Christian Overgaard

    2016-01-01

    The paper describes the structure of the new Danish National Passenger model and provides on this basis a general discussion of large-scale model design, cost-damping and model validation. The paper aims at providing three main contributions to the existing literature. Firstly, at the general level......, the paper provides a description of a large-scale forecast model with a discussion of the linkage between population synthesis, demand and assignment. Secondly, the paper gives specific attention to model specification and in particular choice of functional form and cost-damping. Specifically we suggest...... a family of logarithmic spline functions and illustrate how it is applied in the model. Thirdly and finally, we evaluate model sensitivity and performance by evaluating the distance distribution and elasticities. In the paper we present results where the spline-function is compared with more traditional...

  8. Superconducting solenoid model magnet test results

    Energy Technology Data Exchange (ETDEWEB)

    Carcagno, R.; Dimarco, J.; Feher, S.; Ginsburg, C.M.; Hess, C.; Kashikhin, V.V.; Orris, D.F.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.A.; Terechkine, I.; /Fermilab

    2006-08-01

    Superconducting solenoid magnets suitable for the room temperature front end of the Fermilab High Intensity Neutrino Source (formerly known as Proton Driver), an 8 GeV superconducting H- linac, have been designed and fabricated at Fermilab, and tested in the Fermilab Magnet Test Facility. We report here results of studies on the first model magnets in this program, including the mechanical properties during fabrication and testing in liquid helium at 4.2 K, quench performance, and magnetic field measurements. We also describe new test facility systems and instrumentation that have been developed to accomplish these tests.

  9. Superconducting solenoid model magnet test results

    International Nuclear Information System (INIS)

    Carcagno, R.; Dimarco, J.; Feher, S.; Ginsburg, C.M.; Hess, C.; Kashikhin, V.V.; Orris, D.F.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.A.; Terechkine, I.; Tompkins, J.C.; Wokas, T.; Fermilab

    2006-01-01

    Superconducting solenoid magnets suitable for the room temperature front end of the Fermilab High Intensity Neutrino Source (formerly known as Proton Driver), an 8 GeV superconducting H- linac, have been designed and fabricated at Fermilab, and tested in the Fermilab Magnet Test Facility. We report here results of studies on the first model magnets in this program, including the mechanical properties during fabrication and testing in liquid helium at 4.2 K, quench performance, and magnetic field measurements. We also describe new test facility systems and instrumentation that have been developed to accomplish these tests

  10. Circuit oriented electromagnetic modeling using the PEEC techniques

    CERN Document Server

    Ruehli, Albert; Jiang, Lijun

    2017-01-01

    This book provides intuitive solutions to electromagnetic problems by using the Partial Eelement Eequivalent Ccircuit (PEEC) method. This book begins with an introduction to circuit analysis techniques, laws, and frequency and time domain analyses. The authors also treat Maxwell's equations, capacitance computations, and inductance computations through the lens of the PEEC method. Next, readers learn to build PEEC models in various forms: equivalent circuit models, non orthogonal PEEC models, skin-effect models, PEEC models for dielectrics, incident and radiate field models, and scattering PEEC models. The book concludes by considering issues like such as stability and passivity, and includes five appendices some with formulas for partial elements.

  11. Results and Error Estimates from GRACE Forward Modeling over Antarctica

    Science.gov (United States)

    Bonin, Jennifer; Chambers, Don

    2013-04-01

    Forward modeling using a weighted least squares technique allows GRACE information to be projected onto a pre-determined collection of local basins. This decreases the impact of spatial leakage, allowing estimates of mass change to be better localized. The technique is especially valuable where models of current-day mass change are poor, such as over Antarctica. However when tested previously, the least squares technique has required constraints in the form of added process noise in order to be reliable. Poor choice of local basin layout has also adversely affected results, as has the choice of spatial smoothing used with GRACE. To develop design parameters which will result in correct high-resolution mass detection and to estimate the systematic errors of the method over Antarctica, we use a "truth" simulation of the Antarctic signal. We apply the optimal parameters found from the simulation to RL05 GRACE data across Antarctica and the surrounding ocean. We particularly focus on separating the Antarctic peninsula's mass signal from that of the rest of western Antarctica. Additionally, we characterize how well the technique works for removing land leakage signal from the nearby ocean, particularly that near the Drake Passage.

  12. [Intestinal lengthening techniques: an experimental model in dogs].

    Science.gov (United States)

    Garibay González, Francisco; Díaz Martínez, Daniel Alberto; Valencia Flores, Alejandro; González Hernández, Miguel Angel

    2005-01-01

    To compare two intestinal lengthening procedures in an experimental dog model. Intestinal lengthening is one of the methods for gastrointestinal reconstruction used for treatment of short bowel syndrome. The modification to the Bianchi's technique is an alternative. The modified technique decreases the number of anastomoses to a single one, thus reducing the risk of leaks and strictures. To our knowledge there is not any clinical or experimental report that studied both techniques, so we realized the present report. Twelve creole dogs were operated with the Bianchi technique for intestinal lengthening (group A) and other 12 creole dogs from the same race and weight were operated by the modified technique (Group B). Both groups were compared in relation to operating time, difficulties in technique, cost, intestinal lengthening and anastomoses diameter. There were no statistical difference in the anastomoses diameter (A = 9.0 mm vs. B = 8.5 mm, p = 0.3846). Operating time (142 min vs. 63 min) cost and technique difficulties were lower in group B (p anastomoses (of Group B) and intestinal segments had good blood supply and were patent along their full length. Bianchi technique and the modified technique offer two good reliable alternatives for the treatment of short bowel syndrome. The modified technique improved operating time, cost and technical issues.

  13. Mechanical Properties of Nanostructured Materials Determined Through Molecular Modeling Techniques

    Science.gov (United States)

    Clancy, Thomas C.; Gates, Thomas S.

    2005-01-01

    The potential for gains in material properties over conventional materials has motivated an effort to develop novel nanostructured materials for aerospace applications. These novel materials typically consist of a polymer matrix reinforced with particles on the nanometer length scale. In this study, molecular modeling is used to construct fully atomistic models of a carbon nanotube embedded in an epoxy polymer matrix. Functionalization of the nanotube which consists of the introduction of direct chemical bonding between the polymer matrix and the nanotube, hence providing a load transfer mechanism, is systematically varied. The relative effectiveness of functionalization in a nanostructured material may depend on a variety of factors related to the details of the chemical bonding and the polymer structure at the nanotube-polymer interface. The objective of this modeling is to determine what influence the details of functionalization of the carbon nanotube with the polymer matrix has on the resulting mechanical properties. By considering a range of degree of functionalization, the structure-property relationships of these materials is examined and mechanical properties of these models are calculated using standard techniques.

  14. Modelling Technique for Demonstrating Gravity Collapse Structures in Jointed Rock.

    Science.gov (United States)

    Stimpson, B.

    1979-01-01

    Described is a base-friction modeling technique for studying the development of collapse structures in jointed rocks. A moving belt beneath weak material is designed to simulate gravity. A description is given of the model frame construction. (Author/SA)

  15. VLF surface-impedance modelling techniques for coal exploration

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.; Thiel, D.; O' Keefe, S. [Central Queensland University, Rockhampton, Qld. (Australia). Faculty of Engineering and Physical Systems

    2000-10-01

    New and efficient computational techniques are required for geophysical investigations of coal. This will allow automated inverse analysis procedures to be used for interpretation of field data. In this paper, a number of methods of modelling electromagnetic surface impedance measurements are reviewed, particularly as applied to typical coal seam geology found in the Bowen Basin. At present, the Impedance method and the finite-difference time-domain (FDTD) method appear to offer viable solutions although both have problems. The Impedance method is currently slightly inaccurate, and the FDTD method has large computational demands. In this paper both methods are described and results are presented for a number of geological targets. 17 refs., 14 figs.

  16. A pilot modeling technique for handling-qualities research

    Science.gov (United States)

    Hess, R. A.

    1980-01-01

    A brief survey of the more dominant analysis techniques used in closed-loop handling-qualities research is presented. These techniques are shown to rely on so-called classical and modern analytical models of the human pilot which have their foundation in the analysis and design principles of feedback control. The optimal control model of the human pilot is discussed in some detail and a novel approach to the a priori selection of pertinent model parameters is discussed. Frequency domain and tracking performance data from 10 pilot-in-the-loop simulation experiments involving 3 different tasks are used to demonstrate the parameter selection technique. Finally, the utility of this modeling approach in handling-qualities research is discussed.

  17. Summary on several key techniques in 3D geological modeling.

    Science.gov (United States)

    Mei, Gang

    2014-01-01

    Several key techniques in 3D geological modeling including planar mesh generation, spatial interpolation, and surface intersection are summarized in this paper. Note that these techniques are generic and widely used in various applications but play a key role in 3D geological modeling. There are two essential procedures in 3D geological modeling: the first is the simulation of geological interfaces using geometric surfaces and the second is the building of geological objects by means of various geometric computations such as the intersection of surfaces. Discrete geometric surfaces that represent geological interfaces can be generated by creating planar meshes first and then spatially interpolating; those surfaces intersect and then form volumes that represent three-dimensional geological objects such as rock bodies. In this paper, the most commonly used algorithms of the key techniques in 3D geological modeling are summarized.

  18. In vivo dosimetry for total body irradiation: five‐year results and technique comparison

    Science.gov (United States)

    Warry, Alison J.; Eaton, David J.; Collis, Christopher H.; Rosenberg, Ivan

    2014-01-01

    The aim of this work is to establish if the new CT‐based total body irradiation (TBI) planning techniques used at University College London Hospital (UCLH) and Royal Free Hospital (RFH) are comparable to the previous technique at the Middlesex Hospital (MXH) by analyzing predicted and measured diode results. TBI aims to deliver a homogeneous dose to the entire body, typically using extended SSD fields with beam modulation to limit doses to organs at risk. In vivo dosimetry is used to verify the accuracy of delivered doses. In 2005, when the Middlesex Hospital was decommissioned and merged with UCLH, both UCLH and the RFH introduced updated CT‐planned TBI techniques, based on the old MXH technique. More CT slices and in vivo measurement points were used by both; UCLH introduced a beam modulation technique using MLC segments, while RFH updated to a combination of lead compensators and bolus. Semiconductor diodes were used to measure entrance and exit doses in several anatomical locations along the entire body. Diode results from both centers for over five years of treatments were analyzed and compared to the previous MXH technique for accuracy and precision of delivered doses. The most stable location was the field center with standard deviations of 4.1% (MXH), 3.7% (UCLH), and 1.7% (RFH). The least stable position was the ankles. Mean variation with fraction number was within 1.5% for all three techniques. In vivo dosimetry can be used to verify complex modulated CT‐planned TBI, and demonstrate improvements and limitations in techniques. The results show that the new UCLH technique is no worse than the previous MXH one and comparable to the current RFH technique. PACS numbers: 87.55.Qr, 87.56.N‐ PMID:25207423

  19. Scale Model Thruster Acoustic Measurement Results

    Science.gov (United States)

    Vargas, Magda; Kenny, R. Jeremy

    2013-01-01

    The Space Launch System (SLS) Scale Model Acoustic Test (SMAT) is a 5% scale representation of the SLS vehicle, mobile launcher, tower, and launch pad trench. The SLS launch propulsion system will be comprised of the Rocket Assisted Take-Off (RATO) motors representing the solid boosters and 4 Gas Hydrogen (GH2) thrusters representing the core engines. The GH2 thrusters were tested in a horizontal configuration in order to characterize their performance. In Phase 1, a single thruster was fired to determine the engine performance parameters necessary for scaling a single engine. A cluster configuration, consisting of the 4 thrusters, was tested in Phase 2 to integrate the system and determine their combined performance. Acoustic and overpressure data was collected during both test phases in order to characterize the system's acoustic performance. The results from the single thruster and 4- thuster system are discussed and compared.

  20. CMS standard model Higgs boson results

    Directory of Open Access Journals (Sweden)

    Garcia-Abia Pablo

    2013-11-01

    Full Text Available In July 2012 CMS announced the discovery of a new boson with properties resembling those of the long-sought Higgs boson. The analysis of the proton-proton collision data recorded by the CMS detector at the LHC, corresponding to integrated luminosities of 5.1 fb−1 at √s = 7 TeV and 19.6 fb−1 at √s = 8 TeV, confirm the Higgs-like nature of the new boson, with a signal strength associated with vector bosons and fermions consistent with the expectations for a standard model (SM Higgs boson, and spin-parity clearly favouring the scalar nature of the new boson. In this note I review the updated results of the CMS experiment.

  1. Modelling Extortion Racket Systems: Preliminary Results

    Science.gov (United States)

    Nardin, Luis G.; Andrighetto, Giulia; Székely, Áron; Conte, Rosaria

    Mafias are highly powerful and deeply entrenched organised criminal groups that cause both economic and social damage. Overcoming, or at least limiting, their harmful effects is a societally beneficial objective, which renders its dynamics understanding an objective of both scientific and political interests. We propose an agent-based simulation model aimed at understanding how independent and combined effects of legal and social norm-based processes help to counter mafias. Our results show that legal processes are effective in directly countering mafias by reducing their activities and changing the behaviour of the rest of population, yet they are not able to change people's mind-set that renders the change fragile. When combined with social norm-based processes, however, people's mind-set shifts towards a culture of legality rendering the observed behaviour resilient to change.

  2. New results in the Dual Parton Model

    International Nuclear Information System (INIS)

    Van, J.T.T.; Capella, A.

    1984-01-01

    In this paper, the similarity between the x distribution for particle production and the fragmentation functions are observed in e+e- collisions and in deep inelastic scattering are presented. Based on the observation, the authors develop a complete approach to multiparticle production which incorporates the most important features and concepts learned about high energy collisions. 1. Topological expansion : the dominant diagram at high energy corresponds to the simplest topology. 2. Unitarity : diagrams of various topology contribute to the cross sections in a way that unitary is preserved. 3. Regge behaviour and Duality. 4. Partonic structure of hadrons. These general theoretical ideas, result from many joint experimental and theoretical efforts on the study of soft hadron physics. The dual parton model is able to explain all the experimental features from FNAL to SPS collider energies. It has all the properties of an S-matrix theory and provides a unified description of hadron-hadron, hadron-nucleus and nucleus-nucleus collisions

  3. 3D Modeling Techniques for Print and Digital Media

    Science.gov (United States)

    Stephens, Megan Ashley

    In developing my thesis, I looked to gain skills using ZBrush to create 3D models, 3D scanning, and 3D printing. The models created compared the hearts of several vertebrates and were intended for students attending Comparative Vertebrate Anatomy. I used several resources to create a model of the human heart and was able to work from life while creating heart models from other vertebrates. I successfully learned ZBrush and 3D scanning, and successfully printed 3D heart models. ZBrush allowed me to create several intricate models for use in both animation and print media. The 3D scanning technique did not fit my needs for the project, but may be of use for later projects. I was able to 3D print using two different techniques as well.

  4. Model assessment using a multi-metric ranking technique

    Science.gov (United States)

    Fitzpatrick, P. J.; Lau, Y.; Alaka, G.; Marks, F.

    2017-12-01

    Validation comparisons of multiple models presents challenges when skill levels are similar, especially in regimes dominated by the climatological mean. Assessing skill separation will require advanced validation metrics and identifying adeptness in extreme events, but maintain simplicity for management decisions. Flexibility for operations is also an asset. This work postulates a weighted tally and consolidation technique which ranks results by multiple types of metrics. Variables include absolute error, bias, acceptable absolute error percentages, outlier metrics, model efficiency, Pearson correlation, Kendall's Tau, reliability Index, multiplicative gross error, and root mean squared differences. Other metrics, such as root mean square difference and rank correlation were also explored, but removed when the information was discovered to be generally duplicative to other metrics. While equal weights are applied, weights could be altered depending for preferred metrics. Two examples are shown comparing ocean models' currents and tropical cyclone products, including experimental products. The importance of using magnitude and direction for tropical cyclone track forecasts instead of distance, along-track, and cross-track are discussed. Tropical cyclone intensity and structure prediction are also assessed. Vector correlations are not included in the ranking process, but found useful in an independent context, and will be briefly reported.

  5. A New ABCD Technique to Analyze Business Models & Concepts

    OpenAIRE

    Aithal P. S.; Shailasri V. T.; Suresh Kumar P. M.

    2015-01-01

    Various techniques are used to analyze individual characteristics or organizational effectiveness like SWOT analysis, SWOC analysis, PEST analysis etc. These techniques provide an easy and systematic way of identifying various issues affecting a system and provides an opportunity for further development. Whereas these provide a broad-based assessment of individual institutions and systems, it suffers limitations while applying to business context. The success of any business model depends on ...

  6. Nurse Practitioners' Use of Communication Techniques: Results of a Maryland Oral Health Literacy Survey.

    Science.gov (United States)

    Koo, Laura W; Horowitz, Alice M; Radice, Sarah D; Wang, Min Q; Kleinman, Dushanka V

    2016-01-01

    We examined nurse practitioners' use and opinions of recommended communication techniques for the promotion of oral health as part of a Maryland state-wide oral health literacy assessment. Use of recommended health-literate and patient-centered communication techniques have demonstrated improved health outcomes. A 27-item self-report survey, containing 17 communication technique items, across 5 domains, was mailed to 1,410 licensed nurse practitioners (NPs) in Maryland in 2010. Use of communication techniques and opinions about their effectiveness were analyzed using descriptive statistics. General linear models explored provider and practice characteristics to predict differences in the total number and the mean number of communication techniques routinely used in a week. More than 80% of NPs (N = 194) routinely used 3 of the 7 basic communication techniques: simple language, limiting teaching to 2-3 concepts, and speaking slowly. More than 75% of respondents believed that 6 of the 7 basic communication techniques are effective. Sociodemographic provider characteristics and practice characteristics were not significant predictors of the mean number or the total number of communication techniques routinely used by NPs in a week. Potential predictors for using more of the 7 basic communication techniques, demonstrating significance in one general linear model each, were: assessing the office for user-friendliness and ever taking a communication course in addition to nursing school. NPs in Maryland self-reported routinely using some recommended health-literate communication techniques, with belief in their effectiveness. Our findings suggest that NPs who had assessed the office for patient-friendliness or who had taken a communication course beyond their initial education may be predictors for using more of the 7 basic communication techniques. These self-reported findings should be validated with observational studies. Graduate and continuing education for NPs

  7. Characterising and modelling regolith stratigraphy using multiple geophysical techniques

    Science.gov (United States)

    Thomas, M.; Cremasco, D.; Fotheringham, T.; Hatch, M. A.; Triantifillis, J.; Wilford, J.

    2013-12-01

    -registration, depth correction, etc.) each geophysical profile was evaluated by matching the core data. Applying traditional geophysical techniques, the best profiles were inverted using the core data creating two-dimensional (2-D) stratigraphic regolith models for each transect, and evaluated using independent validation. Next, in a test of an alternative method borrowed from digital soil mapping, the best preprocessed geophysical profiles were co-registered and stratigraphic models for each property created using multivariate environmental correlation. After independent validation, the qualities of the latest models were compared to the traditionally derived 2-D inverted models. Finally, the best overall stratigraphic models were used in conjunction with local environmental data (e.g. geology, geochemistry, terrain, soils) to create conceptual regolith hillslope models for each transect highlighting important features and processes, e.g. morphology, hydropedology and weathering characteristics. Results are presented with recommendations regarding the use of geophysics in modelling regolith stratigraphy at fine scales.

  8. Plasticity models of material variability based on uncertainty quantification techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Reese E. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Rizzi, Francesco [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Boyce, Brad [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Templeton, Jeremy Alan [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Ostien, Jakob [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-11-01

    The advent of fabrication techniques like additive manufacturing has focused attention on the considerable variability of material response due to defects and other micro-structural aspects. This variability motivates the development of an enhanced design methodology that incorporates inherent material variability to provide robust predictions of performance. In this work, we develop plasticity models capable of representing the distribution of mechanical responses observed in experiments using traditional plasticity models of the mean response and recently developed uncertainty quantification (UQ) techniques. Lastly, we demonstrate that the new method provides predictive realizations that are superior to more traditional ones, and how these UQ techniques can be used in model selection and assessing the quality of calibrated physical parameters.

  9. Reactivity change measurements on plutonium-uranium fuel elements in hector experimental techniques and results

    International Nuclear Information System (INIS)

    Tattersall, R.B.; Small, V.G.; MacBean, I.J.; Howe, W.D.

    1964-08-01

    The techniques used in making reactivity change measurements on HECTOR are described and discussed. Pile period measurements were used in the majority of oases, though the pile oscillator technique was used occasionally. These two methods are compared. Flux determinations were made in the vicinity of the fuel element samples using manganese foils, and the techniques used are described and an error assessment made. Results of both reactivity change and flux measurements on 1.2 in. diameter uranium and plutonium-uranium alloy fuel elements are presented, these measurements being carried out in a variety of graphite moderated lattices at temperatures up to 450 deg. C. (author)

  10. Finiteness results for Abelian tree models

    NARCIS (Netherlands)

    Draisma, J.; Eggermont, R.H.

    2015-01-01

    Equivariant tree models are statistical models used in the reconstruction of phylogenetic trees from genetic data. Here equivariant refers to a symmetry group imposed on the root distribution and on the transition matrices in the model. We prove that if that symmetry group is Abelian, then the

  11. Finiteness results for Abelian tree models

    NARCIS (Netherlands)

    Draisma, J.; Eggermont, R.H.

    2012-01-01

    Equivariant tree models are statistical models used in the reconstruction of phylogenetic trees from genetic data. Here equivariant refers to a symmetry group imposed on the root distribution and on the transition matrices in the model. We prove that if that symmetry group is Abelian, then the

  12. Finiteness results for Abelian tree models

    NARCIS (Netherlands)

    Draisma, J.; Eggermont, R.H.

    2015-01-01

    Equivariant tree models are statistical models used in the reconstruction of phylogenetic trees from genetic data. Here equivariant§ refers to a symmetry group imposed on the root distribution and on the transition matrices in the model. We prove that if that symmetry group is Abelian, then the

  13. Liver metastases: interventional therapeutic techniques and results, state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, T.J.; Mueller, P.K.; Mack, M.G.; Straub, R.; Engelmann, K. [Dept. of Radiology, Univ. of Frankfurt (Germany); Neuhaus, P. [Dept. of Surgery, Humboldt University of Berlin (Germany)

    1999-05-01

    The liver is the most common site of metastatic tumour deposits. Hepatic metastases are the major cause of morbidity and mortality in patients with gastrointestinal carcinomas and other malignant tumours. The rationale and results for interventional therapeutic techniques in the treatment of liver metastases are presented. For the treatment of patients with irresectable liver metastases, alternative local ablative therapeutic modalities have been developed. Technique and results of local interventional therapies are presented such as microwave-, radiofrequency (RF)- and ultrasound ablation, and laser-induced interstitial therapy (LITT), cryotherapy and local drug administration such as alcohol injection, endotumoral chemotherapy and regional chemoembolisation. In addition to cryotherapy, all ablative techniques can be performed percutaneously with low morbidity and mortality. Cryotherapy is an effective and precise technique for inducing tumour necrosis, but it is currently performed via laparotomy. Percutaneous local alcohol injection results in an inhomogeneous distribution in liver metastases with unreliable control rates. Local chemotherapeutic drug instillation and regional chemoembolisation produces relevant but non-reproducible lesions. Laser-induced interstitial thermotherapy (LITT) performed under MRI guidance results in precise and reproducible areas of induced necrosis with a local control of 94 %, and with an improved survival rate. Interventional therapeutic techniques of liver metastases do result in a remarkable local tumour control rate with improved survival results. (orig.) With 5 figs., 1 tab., 43 refs.

  14. Liver metastases: interventional therapeutic techniques and results, state of the art

    International Nuclear Information System (INIS)

    Vogl, T.J.; Mueller, P.K.; Mack, M.G.; Straub, R.; Engelmann, K.; Neuhaus, P.

    1999-01-01

    The liver is the most common site of metastatic tumour deposits. Hepatic metastases are the major cause of morbidity and mortality in patients with gastrointestinal carcinomas and other malignant tumours. The rationale and results for interventional therapeutic techniques in the treatment of liver metastases are presented. For the treatment of patients with irresectable liver metastases, alternative local ablative therapeutic modalities have been developed. Technique and results of local interventional therapies are presented such as microwave-, radiofrequency (RF)- and ultrasound ablation, and laser-induced interstitial therapy (LITT), cryotherapy and local drug administration such as alcohol injection, endotumoral chemotherapy and regional chemoembolisation. In addition to cryotherapy, all ablative techniques can be performed percutaneously with low morbidity and mortality. Cryotherapy is an effective and precise technique for inducing tumour necrosis, but it is currently performed via laparotomy. Percutaneous local alcohol injection results in an inhomogeneous distribution in liver metastases with unreliable control rates. Local chemotherapeutic drug instillation and regional chemoembolisation produces relevant but non-reproducible lesions. Laser-induced interstitial thermotherapy (LITT) performed under MRI guidance results in precise and reproducible areas of induced necrosis with a local control of 94 %, and with an improved survival rate. Interventional therapeutic techniques of liver metastases do result in a remarkable local tumour control rate with improved survival results. (orig.)

  15. Radiation therapy for retinoblastoma: comparison of results with lens-sparing versus lateral beam techniques

    International Nuclear Information System (INIS)

    McCormick, B.; Ellsworth, R.; Abramson, D.; Haik, B.; Tome, M.; Grabowski, E.; LoSasso, T.

    1988-01-01

    From 1979 through 1986, 170 children were seen at our institution diagnosed with retinoblastoma. Sixty-six of the children with involvement of 121 eyes, were referred for definitive external beam radiation to one or both eyes. During the study period, two distinct radiation techniques were used. From 1980 through mid-1984, a lens-sparing technique included an anterior electron beam with a contact lens mounted lead shield, combined with a lateral field, was used. Since mid-1984, a modified lateral beam technique has been used, mixing lateral electrons and superior and inferior lateral oblique split beam wedged photons. Doses prescribed were similar for both techniques, ranging from 3,850 to 5,000 cGy in 4 to 5 weeks. The lens-sparing and the modified lateral techniques are compared for local control. For eyes with Group I through III disease, the lens-sparing technique resulted in local control in 33% of the eyes treated, where the modified lateral technique controlled 83% of the eyes treated (p = .006). Mean time to relapse was identical in both groups, that is 24 and 26 months respectively. Most relapses were successfully treated with further local therapy, including laser or cryosurgery, or 60Co plaques. Five eyes required enucleation following initial treatment with the lens-sparing technique, but none thus far with the lateral beam technique. For eyes with Group IV and V disease, no significant differences were found between the two techniques in terms of local control or eventual need for enucleation. With a mean follow-up time of 33 months for the entire group, the 4-year survival is 93%. Two of the 4 deaths are due to second primary tumor, and all 4 have occurred in the lens-sparing group. Because follow-up time is more limited in the lateral beam group, this is not statistically significant and direct survival comparisons are premature

  16. Linkage of PRA models. Phase 1, Results

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.L.; Knudsen, J.K.; Kelly, D.L.

    1995-12-01

    The goal of the Phase I work of the ``Linkage of PRA Models`` project was to postulate methods of providing guidance for US Nuclear Regulator Commission (NRC) personnel on the selection and usage of probabilistic risk assessment (PRA) models that are best suited to the analysis they are performing. In particular, methods and associated features are provided for (a) the selection of an appropriate PRA model for a particular analysis, (b) complementary evaluation tools for the analysis, and (c) a PRA model cross-referencing method. As part of this work, three areas adjoining ``linking`` analyses to PRA models were investigated: (a) the PRA models that are currently available, (b) the various types of analyses that are performed within the NRC, and (c) the difficulty in trying to provide a ``generic`` classification scheme to groups plants based upon a particular plant attribute.

  17. Linkage of PRA models. Phase 1, Results

    International Nuclear Information System (INIS)

    Smith, C.L.; Knudsen, J.K.; Kelly, D.L.

    1995-12-01

    The goal of the Phase I work of the ''Linkage of PRA Models'' project was to postulate methods of providing guidance for US Nuclear Regulator Commission (NRC) personnel on the selection and usage of probabilistic risk assessment (PRA) models that are best suited to the analysis they are performing. In particular, methods and associated features are provided for (a) the selection of an appropriate PRA model for a particular analysis, (b) complementary evaluation tools for the analysis, and (c) a PRA model cross-referencing method. As part of this work, three areas adjoining ''linking'' analyses to PRA models were investigated: (a) the PRA models that are currently available, (b) the various types of analyses that are performed within the NRC, and (c) the difficulty in trying to provide a ''generic'' classification scheme to groups plants based upon a particular plant attribute

  18. Engineering Glass Passivation Layers -Model Results

    Energy Technology Data Exchange (ETDEWEB)

    Skorski, Daniel C.; Ryan, Joseph V.; Strachan, Denis M.; Lepry, William C.

    2011-08-08

    The immobilization of radioactive waste into glass waste forms is a baseline process of nuclear waste management not only in the United States, but worldwide. The rate of radionuclide release from these glasses is a critical measure of the quality of the waste form. Over long-term tests and using extrapolations of ancient analogues, it has been shown that well designed glasses exhibit a dissolution rate that quickly decreases to a slow residual rate for the lifetime of the glass. The mechanistic cause of this decreased corrosion rate is a subject of debate, with one of the major theories suggesting that the decrease is caused by the formation of corrosion products in such a manner as to present a diffusion barrier on the surface of the glass. Although there is much evidence of this type of mechanism, there has been no attempt to engineer the effect to maximize the passivating qualities of the corrosion products. This study represents the first attempt to engineer the creation of passivating phases on the surface of glasses. Our approach utilizes interactions between the dissolving glass and elements from the disposal environment to create impermeable capping layers. By drawing from other corrosion studies in areas where passivation layers have been successfully engineered to protect the bulk material, we present here a report on mineral phases that are likely have a morphological tendency to encrust the surface of the glass. Our modeling has focused on using the AFCI glass system in a carbonate, sulfate, and phosphate rich environment. We evaluate the minerals predicted to form to determine the likelihood of the formation of a protective layer on the surface of the glass. We have also modeled individual ions in solutions vs. pH and the addition of aluminum and silicon. These results allow us to understand the pH and ion concentration dependence of mineral formation. We have determined that iron minerals are likely to form a complete incrustation layer and we plan

  19. CIEMAT model results for Esthwaite Water

    International Nuclear Information System (INIS)

    Aguero, A.; Garcia-Olivares, A.

    2000-01-01

    This study used the transfer model PRYMA-LO, developed by CIEMAT-IMA, Madrid, Spain, to simulate the transfer of Cs-137 in watershed scenarios. The main processes considered by the model include: transfer of the fallout to the ground, incorporation of the fallout radioisotopes into the water flow, and their removal from the system. The model was tested against observation data obtained in water and sediments of Esthwaite Water, Lake District, UK. This comparison made it possible to calibrate the parameters of the model to the specific scenario

  20. Plants status monitor: Modelling techniques and inherent benefits

    International Nuclear Information System (INIS)

    Breeding, R.J.; Lainoff, S.M.; Rees, D.C.; Prather, W.A.; Fickiessen, K.O.E.

    1987-01-01

    The Plant Status Monitor (PSM) is designed to provide plant personnel with information on the operational status of the plant and compliance with the plant technical specifications. The PSM software evaluates system models using a 'distributed processing' technique in which detailed models of individual systems are processed rather than by evaluating a single, plant-level model. In addition, development of the system models for PSM provides inherent benefits to the plant by forcing detailed reviews of the technical specifications, system design and operating procedures, and plant documentation. (orig.)

  1. Modeling and Simulation Techniques for Large-Scale Communications Modeling

    National Research Council Canada - National Science Library

    Webb, Steve

    1997-01-01

    .... Tests of random number generators were also developed and applied to CECOM models. It was found that synchronization of random number strings in simulations is easy to implement and can provide significant savings for making comparative studies. If synchronization is in place, then statistical experiment design can be used to provide information on the sensitivity of the output to input parameters. The report concludes with recommendations and an implementation plan.

  2. Modeling and design techniques for RF power amplifiers

    CERN Document Server

    Raghavan, Arvind; Laskar, Joy

    2008-01-01

    The book covers RF power amplifier design, from device and modeling considerations to advanced circuit design architectures and techniques. It focuses on recent developments and advanced topics in this area, including numerous practical designs to back the theoretical considerations. It presents the challenges in designing power amplifiers in silicon and helps the reader improve the efficiency of linear power amplifiers, and design more accurate compact device models, with faster extraction routines, to create cost effective and reliable circuits.

  3. Techniques for discrimination-free predictive models (Chapter 12)

    NARCIS (Netherlands)

    Kamiran, F.; Calders, T.G.K.; Pechenizkiy, M.; Custers, B.H.M.; Calders, T.G.K.; Schermer, B.W.; Zarsky, T.Z.

    2013-01-01

    In this chapter, we give an overview of the techniques developed ourselves for constructing discrimination-free classifiers. In discrimination-free classification the goal is to learn a predictive model that classifies future data objects as accurately as possible, yet the predicted labels should be

  4. Using of Structural Equation Modeling Techniques in Cognitive Levels Validation

    Directory of Open Access Journals (Sweden)

    Natalija Curkovic

    2012-10-01

    Full Text Available When constructing knowledge tests, cognitive level is usually one of the dimensions comprising the test specifications with each item assigned to measure a particular level. Recently used taxonomies of the cognitive levels most often represent some modification of the original Bloom’s taxonomy. There are many concerns in current literature about existence of predefined cognitive levels. The aim of this article is to investigate can structural equation modeling techniques confirm existence of different cognitive levels. For the purpose of the research, a Croatian final high-school Mathematics exam was used (N = 9626. Confirmatory factor analysis and structural regression modeling were used to test three different models. Structural equation modeling techniques did not support existence of different cognitive levels in this case. There is more than one possible explanation for that finding. Some other techniques that take into account nonlinear behaviour of the items as well as qualitative techniques might be more useful for the purpose of the cognitive levels validation. Furthermore, it seems that cognitive levels were not efficient descriptors of the items and so improvements are needed in describing the cognitive skills measured by items.

  5. NMR and modelling techniques in structural and conformation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, R J [Liverpool Univ. (United Kingdom)

    1994-12-31

    The use of Lanthanide Induced Shifts (L.I.S.) and modelling techniques in conformational analysis is presented. The use of Co{sup III} porphyrins as shift reagents is discussed, with examples of their use in the conformational analysis of some heterocyclic amines. (author) 13 refs., 9 figs.

  6. Air quality modelling using chemometric techniques | Azid | Journal ...

    African Journals Online (AJOL)

    This study presents that the chemometric techniques and modelling become an excellent tool in API assessment, air pollution source identification, apportionment and can be setbacks in designing an API monitoring network for effective air pollution resources management. Keywords: air pollutant index; chemometric; ANN; ...

  7. Flying Training Capacity Model: Initial Results

    National Research Council Canada - National Science Library

    Lynch, Susan

    2005-01-01

    OBJECTIVE: (1) Determine the flying training capacity for 6 bases: * Sheppard AFB * Randolph AFB * Moody AFB * Columbus AFB * Laughlin AFB * Vance AFB * (2) Develop versatile flying training capacity simulation model for AETC...

  8. The phase field technique for modeling multiphase materials

    Science.gov (United States)

    Singer-Loginova, I.; Singer, H. M.

    2008-10-01

    This paper reviews methods and applications of the phase field technique, one of the fastest growing areas in computational materials science. The phase field method is used as a theory and computational tool for predictions of the evolution of arbitrarily shaped morphologies and complex microstructures in materials. In this method, the interface between two phases (e.g. solid and liquid) is treated as a region of finite width having a gradual variation of different physical quantities, i.e. it is a diffuse interface model. An auxiliary variable, the phase field or order parameter \\phi(\\vec{x}) , is introduced, which distinguishes one phase from the other. Interfaces are identified by the variation of the phase field. We begin with presenting the physical background of the phase field method and give a detailed thermodynamical derivation of the phase field equations. We demonstrate how equilibrium and non-equilibrium physical phenomena at the phase interface are incorporated into the phase field methods. Then we address in detail dendritic and directional solidification of pure and multicomponent alloys, effects of natural convection and forced flow, grain growth, nucleation, solid-solid phase transformation and highlight other applications of the phase field methods. In particular, we review the novel phase field crystal model, which combines atomistic length scales with diffusive time scales. We also discuss aspects of quantitative phase field modeling such as thin interface asymptotic analysis and coupling to thermodynamic databases. The phase field methods result in a set of partial differential equations, whose solutions require time-consuming large-scale computations and often limit the applicability of the method. Subsequently, we review numerical approaches to solve the phase field equations and present a finite difference discretization of the anisotropic Laplacian operator.

  9. TAPP - Stuttgart technique and result of a large single center series

    Directory of Open Access Journals (Sweden)

    Bittner R

    2006-01-01

    Full Text Available Laparoscopic hernioplasty is assessed as a difficult operation. Operative technique determines the frequency of complications, the time of recovery and the rate of recurrences. A proper technique is absolutely necessary to achieve results that are superior to open hernia surgery. Technique: The key points in our technique are 1 use of nondisposable instruments; 2 use of blunt trocars, consisting of expanding and non-incisive cone-shaped tips; 3 spacious and curved opening to the peritoneum, high above all possible hernia openings; 4 meticulous dissection of the entire pelvic floor; 5 complete reduction of the hernial sac; 6 wide parietalization of the peritoneal sac, at least down to the mid of psoas muscle; 7 implantation of a large mesh, at least 10 cm x 15 cm; 8 fixation of the mesh by clip to Cooper′s ligament, to the rectus muscle and lateral to the epigastric vessels, high above the ileopubic tract; 9 the use of glue allows fixation also to the latero-caudial region; and 10 closure of the peritoneum by running suture. Results: With this technique in 12,678 hernia repairs, the following results could be achieved: operating time - 40 min; morbidity - 2.9%; recurrence rate - 0.7%; disability of work - 14 days. In all types of hernias (recurrence after previous open surgery, recurrence after previous preperitoneal operation, scrotal hernia, hernia in patients after transabdominal prostate resection, similar results could be achieved. Summary: Laparoscopic hernia repair can be performed successfully in clinical practice even by surgeons in training. Precondition for the success is a strictly standardized operative technique and a well-structured educational program.

  10. New techniques and results for worldline simulations of lattice field theories

    Science.gov (United States)

    Giuliani, Mario; Orasch, Oliver; Gattringer, Christof

    2018-03-01

    We use the complex ø4 field at finite density as a model system for developing further techniques based on worldline formulations of lattice field theories. More specifically we: 1) Discuss new variants of the worm algorithm for updating the ø4 theory and related systems with site weights. 2) Explore the possibility of canonical simulations in the worldline formulation. 3) Study the connection of 2-particle condensation at low temperature to scattering parameters of the theory.

  11. Spatial Modeling of Geometallurgical Properties: Techniques and a Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, Jared L., E-mail: jdeutsch@ualberta.ca [University of Alberta, School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering (Canada); Palmer, Kevin [Teck Resources Limited (Canada); Deutsch, Clayton V.; Szymanski, Jozef [University of Alberta, School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering (Canada); Etsell, Thomas H. [University of Alberta, Department of Chemical and Materials Engineering (Canada)

    2016-06-15

    High-resolution spatial numerical models of metallurgical properties constrained by geological controls and more extensively by measured grade and geomechanical properties constitute an important part of geometallurgy. Geostatistical and other numerical techniques are adapted and developed to construct these high-resolution models accounting for all available data. Important issues that must be addressed include unequal sampling of the metallurgical properties versus grade assays, measurements at different scale, and complex nonlinear averaging of many metallurgical parameters. This paper establishes techniques to address each of these issues with the required implementation details and also demonstrates geometallurgical mineral deposit characterization for a copper–molybdenum deposit in South America. High-resolution models of grades and comminution indices are constructed, checked, and are rigorously validated. The workflow demonstrated in this case study is applicable to many other deposit types.

  12. A fermionic molecular dynamics technique to model nuclear matter

    International Nuclear Information System (INIS)

    Vantournhout, K.; Jachowicz, N.; Ryckebusch, J.

    2009-01-01

    Full text: At sub-nuclear densities of about 10 14 g/cm 3 , nuclear matter arranges itself in a variety of complex shapes. This can be the case in the crust of neutron stars and in core-collapse supernovae. These slab like and rod like structures, designated as nuclear pasta, have been modelled with classical molecular dynamics techniques. We present a technique, based on fermionic molecular dynamics, to model nuclear matter at sub-nuclear densities in a semi classical framework. The dynamical evolution of an antisymmetric ground state is described making the assumption of periodic boundary conditions. Adding the concepts of antisymmetry, spin and probability distributions to classical molecular dynamics, brings the dynamical description of nuclear matter to a quantum mechanical level. Applications of this model vary from investigation of macroscopic observables and the equation of state to the study of fundamental interactions on the microscopic structure of the matter. (author)

  13. Variability and trends in the Arctic Sea ice cover: Results from different techniques

    Science.gov (United States)

    Comiso, Josefino C.; Meier, Walter N.; Gersten, Robert

    2017-08-01

    this study, a comparison of results from four different techniques that are frequently used shows significant disagreements in the characterization of the distribution of the sea ice cover primarily in areas that have a large fraction of new ice cover or significant amount of surface melt. However, the actual changes in the ice cover are consistently depicted and the trends in sea ice extent and ice area from the different data sets are practically the same providing strong confidence that satellite data are interpreted consistently by different scientists independently and confirming that the ice extent of the Arctic perennial ice is indeed declining at the rate of about 11% per decade. The results provide useful information for modelers, policy makers, and the general scientific public.

  14. Model technique for aerodynamic study of boiler furnace

    Energy Technology Data Exchange (ETDEWEB)

    1966-02-01

    The help of the Division was recently sought to improve the heat transfer and reduce the exit gas temperature in a pulverized-fuel-fired boiler at an Australian power station. One approach adopted was to construct from Perspex a 1:20 scale cold-air model of the boiler furnace and to use a flow-visualization technique to study the aerodynamic patterns established when air was introduced through the p.f. burners of the model. The work established good correlations between the behaviour of the model and of the boiler furnace.

  15. Line impedance estimation using model based identification technique

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai; Agelidis, Vassilios; Teodorescu, Remus

    2011-01-01

    The estimation of the line impedance can be used by the control of numerous grid-connected systems, such as active filters, islanding detection techniques, non-linear current controllers, detection of the on/off grid operation mode. Therefore, estimating the line impedance can add extra functions...... into the operation of the grid-connected power converters. This paper describes a quasi passive method for estimating the line impedance of the distribution electricity network. The method uses the model based identification technique to obtain the resistive and inductive parts of the line impedance. The quasi...

  16. Graphical interpretation of numerical model results

    International Nuclear Information System (INIS)

    Drewes, D.R.

    1979-01-01

    Computer software has been developed to produce high quality graphical displays of data from a numerical grid model. The code uses an existing graphical display package (DISSPLA) and overcomes some of the problems of both line-printer output and traditional graphics. The software has been designed to be flexible enough to handle arbitrarily placed computation grids and a variety of display requirements

  17. Model-checking techniques based on cumulative residuals.

    Science.gov (United States)

    Lin, D Y; Wei, L J; Ying, Z

    2002-03-01

    Residuals have long been used for graphical and numerical examinations of the adequacy of regression models. Conventional residual analysis based on the plots of raw residuals or their smoothed curves is highly subjective, whereas most numerical goodness-of-fit tests provide little information about the nature of model misspecification. In this paper, we develop objective and informative model-checking techniques by taking the cumulative sums of residuals over certain coordinates (e.g., covariates or fitted values) or by considering some related aggregates of residuals, such as moving sums and moving averages. For a variety of statistical models and data structures, including generalized linear models with independent or dependent observations, the distributions of these stochastic processes tinder the assumed model can be approximated by the distributions of certain zero-mean Gaussian processes whose realizations can be easily generated by computer simulation. Each observed process can then be compared, both graphically and numerically, with a number of realizations from the Gaussian process. Such comparisons enable one to assess objectively whether a trend seen in a residual plot reflects model misspecification or natural variation. The proposed techniques are particularly useful in checking the functional form of a covariate and the link function. Illustrations with several medical studies are provided.

  18. Endovascular Aortic Aneurysm Repair with Chimney and Snorkel Grafts: Indications, Techniques and Results

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Rakesh P., E-mail: rpatel9@nhs.net [Northwick Park Hospital, Department of Vascular Radiology (United Kingdom); Katsargyris, Athanasios, E-mail: kthanassos@yahoo.com; Verhoeven, Eric L. G., E-mail: Eric.Verhoeven@klinikum-nuernberg.de [Klinikum Nuernberg, Department of Vascular and Endovascular Surgery (Germany); Adam, Donald J., E-mail: donald.adam@tiscali.co.uk [Heartlands Hospital, Department of Vascular Surgery (United Kingdom); Hardman, John A., E-mail: johnhardman@doctors.org.uk [Royal United Hospital Bath, Department of Vascular Radiology (United Kingdom)

    2013-12-15

    The chimney technique in endovascular aortic aneurysm repair (Ch-EVAR) involves placement of a stent or stent-graft parallel to the main aortic stent-graft to extend the proximal or distal sealing zone while maintaining side branch patency. Ch-EVAR can facilitate endovascular repair of juxtarenal and aortic arch pathology using available standard aortic stent-grafts, therefore, eliminating the manufacturing delays required for customised fenestrated and branched stent-grafts. Several case series have demonstrated the feasibility of Ch-EVAR both in acute and elective cases with good early results. This review discusses indications, technique, and the current available clinical data on Ch-EVAR.

  19. Abnormal urinalysis results are common, regardless of specimen collection technique, in women without urinary tract infections.

    Science.gov (United States)

    Frazee, Bradley W; Enriquez, Kayla; Ng, Valerie; Alter, Harrison

    2015-06-01

    Voided urinalysis to test for urinary tract infection (UTI) is prone to false-positive results for a number of reasons. Specimens are often collected at triage from women with any abdominal complaint, creating a low UTI prevalence population. Improper collection technique by the patient may affect the result. At least four indices, if positive, can indicate UTI. We examine the impact of voided specimen collection technique on urinalysis indicators of UTI and on urine culture contamination in disease-free women. In this crossover design, 40 menstrual-age female emergency department staff without UTI symptoms collected urine two ways: directly in a cup ("non-clean") and midstream clean catch ("ideal"). Samples underwent standard automated urinalysis and culture. Urinalysis indices and culture contamination were compared. The proportion of abnormal results from samples collected by "non-clean" vs. "ideal" technique, respectively, were: leukocyte esterase (>trace) 50%, 35% (95% confidence interval for difference -6% to 36%); nitrites (any) 2.5%, 2.5% (difference -2.5 to 2.5%); white blood cells (>5/high-powered field [HPF]) 50%, 27.5% (difference 4 to 41%); bacteria (any/HPF) 77.5%, 62.5%, (difference -7 to 37%); epithelial cells (>few) 65%, 30% (difference 13 to 56%); culture contamination (>1000 colony-forming units of commensal or >2 species) 77%, 63% (difference -5 to 35%). No urinalysis index was positively correlated with culture contamination. Contemporary automated urinalysis indices were often abnormal in a disease-free population of women, even using ideal collection technique. In clinical practice, such false-positive results could lead to false-positive UTI diagnosis. Only urine nitrite showed a high specificity. Culture contamination was common regardless of collection technique and was not predicted by urinalysis results. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Adaptive subdomain modeling: A multi-analysis technique for ocean circulation models

    Science.gov (United States)

    Altuntas, Alper; Baugh, John

    2017-07-01

    Many coastal and ocean processes of interest operate over large temporal and geographical scales and require a substantial amount of computational resources, particularly when engineering design and failure scenarios are also considered. This study presents an adaptive multi-analysis technique that improves the efficiency of these computations when multiple alternatives are being simulated. The technique, called adaptive subdomain modeling, concurrently analyzes any number of child domains, with each instance corresponding to a unique design or failure scenario, in addition to a full-scale parent domain providing the boundary conditions for its children. To contain the altered hydrodynamics originating from the modifications, the spatial extent of each child domain is adaptively adjusted during runtime depending on the response of the model. The technique is incorporated in ADCIRC++, a re-implementation of the popular ADCIRC ocean circulation model with an updated software architecture designed to facilitate this adaptive behavior and to utilize concurrent executions of multiple domains. The results of our case studies confirm that the method substantially reduces computational effort while maintaining accuracy.

  1. Space Geodetic Technique Co-location in Space: Simulation Results for the GRASP Mission

    Science.gov (United States)

    Kuzmicz-Cieslak, M.; Pavlis, E. C.

    2011-12-01

    The Global Geodetic Observing System-GGOS, places very stringent requirements in the accuracy and stability of future realizations of the International Terrestrial Reference Frame (ITRF): an origin definition at 1 mm or better at epoch and a temporal stability on the order of 0.1 mm/y, with similar numbers for the scale (0.1 ppb) and orientation components. These goals were derived from the requirements of Earth science problems that are currently the international community's highest priority. None of the geodetic positioning techniques can achieve this goal alone. This is due in part to the non-observability of certain attributes from a single technique. Another limitation is imposed from the extent and uniformity of the tracking network and the schedule of observational availability and number of suitable targets. The final limitation derives from the difficulty to "tie" the reference points of each technique at the same site, to an accuracy that will support the GGOS goals. The future GGOS network will address decisively the ground segment and to certain extent the space segment requirements. The JPL-proposed multi-technique mission GRASP (Geodetic Reference Antenna in Space) attempts to resolve the accurate tie between techniques, using their co-location in space, onboard a well-designed spacecraft equipped with GNSS receivers, a SLR retroreflector array, a VLBI beacon and a DORIS system. Using the anticipated system performance for all four techniques at the time the GGOS network is completed (ca 2020), we generated a number of simulated data sets for the development of a TRF. Our simulation studies examine the degree to which GRASP can improve the inter-technique "tie" issue compared to the classical approach, and the likely modus operandi for such a mission. The success of the examined scenarios is judged by the quality of the origin and scale definition of the resulting TRF.

  2. Therapeutic Results of Radiotherapy in Rectal Carcinoma -Comparison of Sandwich Technique Radiotherapy with Postoperative Radiotherapy

    International Nuclear Information System (INIS)

    Huh, Gil Cha; Suh, Hyun Suk; Lee, Hyuk Sang; Kim, Re Hwe; Kim, Chul Soo; Kim, Hong Yong; Kim, Sung Rok

    1996-01-01

    Purpose : To evaluate the potential advantage for 'sandwich' technique radiotherapy compared to postoperative radiotherapy in respectable rectal cancer. Between January 1989 and May 1994, 60 patients with respectable rectal cancer were treated at Inje University Seoul and Sanggye Paik Hospital.Fifty one patients were available for analysis : 20 patients were treated with sandwich technique radiotherapy and 31 patients were treated with postoperative radiotherapy. In sandwich technique radiotherapy(RT), patients were treated with preoperative RT 1500 cGy/5fx followed by immediate curative resection. Patients staged as Astler-Coller B2, C were considered for postoperative RT with 2500-4500 cGy. In postoperative RT, total radiation dose of 4500-6120 cGy, 180 cGy daily at 4-6 weeks was delivered. Patients were followed for median period of 25 months. Results : The overall 5-year survival rates for sandwich technique RT group and postoperative RT group were 60% and 71%, respectively(p>0.05). The 5-year disease free survival rates for each group were 63%. There was no difference in local failure rate between two groups(11% versus 7%). Incidence of distant metastasis was 11%(2/20) in the sandwich technique RT group and 20%(6/31) in the postoperative RT group(p>0.05). The frequencies of acute and chronic complications were comparable in both groups. Conclusion : The sandwich technique radiotherapy group shows local recurrence and survival similar to those of postoperative RT alone group but reduced distant metastasis compared to postoperative RT group. But long term follow-up and large number of patients is needed to make an any firm conclusion regarding the value of this sandwich technique RT

  3. Ignalina NPP Safety Analysis: Models and Results

    International Nuclear Information System (INIS)

    Uspuras, E.

    1999-01-01

    Research directions, linked to safety assessment of the Ignalina NPP, of the scientific safety analysis group are presented: Thermal-hydraulic analysis of accidents and operational transients; Thermal-hydraulic assessment of Ignalina NPP Accident Localization System and other compartments; Structural analysis of plant components, piping and other parts of Main Circulation Circuit; Assessment of RBMK-1500 reactor core and other. Models and main works carried out last year are described. (author)

  4. The Effect of Learning Based on Technology Model and Assessment Technique toward Thermodynamic Learning Achievement

    Science.gov (United States)

    Makahinda, T.

    2018-02-01

    The purpose of this research is to find out the effect of learning model based on technology and assessment technique toward thermodynamic achievement by controlling students intelligence. This research is an experimental research. The sample is taken through cluster random sampling with the total respondent of 80 students. The result of the research shows that the result of learning of thermodynamics of students who taught the learning model of environmental utilization is higher than the learning result of student thermodynamics taught by simulation animation, after controlling student intelligence. There is influence of student interaction, and the subject between models of technology-based learning with assessment technique to student learning result of Thermodynamics, after controlling student intelligence. Based on the finding in the lecture then should be used a thermodynamic model of the learning environment with the use of project assessment technique.

  5. Monosomy 3 by FISH in uveal melanoma: variability in techniques and results.

    Science.gov (United States)

    Aronow, Mary; Sun, Yang; Saunthararajah, Yogen; Biscotti, Charles; Tubbs, Raymond; Triozzi, Pierre; Singh, Arun D

    2012-09-01

    Tumor monosomy 3 confers a poor prognosis in patients with uveal melanoma. We critically review the techniques used for fluorescence in situ hybridization (FISH) detection of monosomy 3 in order to assess variability in practice patterns and to explain differences in results. Significant variability that has likely affected reported results was found in tissue sampling methods, selection of FISH probes, number of cells counted, and the cut-off point used to determine monosomy 3 status. Clinical parameters and specific techniques employed to report FISH results should be specified so as to allow meta-analysis of published studies. FISH-based detection of monosomy 3 in uveal melanoma has not been performed in a standardized manner, which limits conclusions regarding its clinical utility. FISH is a widely available, versatile technology, and when performed optimally has the potential to be a valuable tool for determining the prognosis of uveal melanoma. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Use of hydrological modelling and isotope techniques in Guvenc basin

    International Nuclear Information System (INIS)

    Altinbilek, D.

    1991-07-01

    The study covers the work performed under Project No. 335-RC-TUR-5145 entitled ''Use of Hydrologic Modelling and Isotope Techniques in Guvenc Basin'' and is an initial part of a program for estimating runoff from Central Anatolia Watersheds. The study presented herein consists of mainly three parts: 1) the acquisition of a library of rainfall excess, direct runoff and isotope data for Guvenc basin; 2) the modification of SCS model to be applied to Guvenc basin first and then to other basins of Central Anatolia for predicting the surface runoff from gaged and ungaged watersheds; and 3) the use of environmental isotope technique in order to define the basin components of streamflow of Guvenc basin. 31 refs, figs and tabs

  7. Microplasticity of MMC. Experimental results and modelling

    International Nuclear Information System (INIS)

    Maire, E.; Lormand, G.; Gobin, P.F.; Fougeres, R.

    1993-01-01

    The microplastic behavior of several MMC is investigated by means of tension and compression tests. This behavior is assymetric : the proportional limit is higher in tension than in compression but the work hardening rate is higher in compression. These differences are analysed in terms of maxium of the Tresca's shear stress at the interface (proportional limit) and of the emission of dislocation loops during the cooling (work hardening rate). On another hand, a model is proposed to calculate the value of the yield stress, describing the composite as a material composed of three phases : inclusion, unaffected matrix and matrix surrounding the inclusion having a gradient in the density of the thermally induced dilocations. (orig.)

  8. Microplasticity of MMC. Experimental results and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Maire, E. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Lormand, G. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Gobin, P.F. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France)); Fougeres, R. (Groupe d' Etude de Metallurgie Physique et de Physique des Materiaux, INSA, 69 Villeurbanne (France))

    1993-11-01

    The microplastic behavior of several MMC is investigated by means of tension and compression tests. This behavior is assymetric : the proportional limit is higher in tension than in compression but the work hardening rate is higher in compression. These differences are analysed in terms of maxium of the Tresca's shear stress at the interface (proportional limit) and of the emission of dislocation loops during the cooling (work hardening rate). On another hand, a model is proposed to calculate the value of the yield stress, describing the composite as a material composed of three phases : inclusion, unaffected matrix and matrix surrounding the inclusion having a gradient in the density of the thermally induced dilocations. (orig.).

  9. Towards Model Validation and Verification with SAT Techniques

    OpenAIRE

    Gogolla, Martin

    2010-01-01

    After sketching how system development and the UML (Unified Modeling Language) and the OCL (Object Constraint Language) are related, validation and verification with the tool USE (UML-based Specification Environment) is demonstrated. As a more efficient alternative for verification tasks, two approaches using SAT-based techniques are put forward: First, a direct encoding of UML and OCL with Boolean variables and propositional formulas, and second, an encoding employing an...

  10. [Preparation of simulate craniocerebral models via three dimensional printing technique].

    Science.gov (United States)

    Lan, Q; Chen, A L; Zhang, T; Zhu, Q; Xu, T

    2016-08-09

    Three dimensional (3D) printing technique was used to prepare the simulate craniocerebral models, which were applied to preoperative planning and surgical simulation. The image data was collected from PACS system. Image data of skull bone, brain tissue and tumors, cerebral arteries and aneurysms, and functional regions and relative neural tracts of the brain were extracted from thin slice scan (slice thickness 0.5 mm) of computed tomography (CT), magnetic resonance imaging (MRI, slice thickness 1mm), computed tomography angiography (CTA), and functional magnetic resonance imaging (fMRI) data, respectively. MIMICS software was applied to reconstruct colored virtual models by identifying and differentiating tissues according to their gray scales. Then the colored virtual models were submitted to 3D printer which produced life-sized craniocerebral models for surgical planning and surgical simulation. 3D printing craniocerebral models allowed neurosurgeons to perform complex procedures in specific clinical cases though detailed surgical planning. It offered great convenience for evaluating the size of spatial fissure of sellar region before surgery, which helped to optimize surgical approach planning. These 3D models also provided detailed information about the location of aneurysms and their parent arteries, which helped surgeons to choose appropriate aneurismal clips, as well as perform surgical simulation. The models further gave clear indications of depth and extent of tumors and their relationship to eloquent cortical areas and adjacent neural tracts, which were able to avoid surgical damaging of important neural structures. As a novel and promising technique, the application of 3D printing craniocerebral models could improve the surgical planning by converting virtual visualization into real life-sized models.It also contributes to functional anatomy study.

  11. Meteorological uncertainty of atmospheric dispersion model results (MUD)

    Energy Technology Data Exchange (ETDEWEB)

    Havskov Soerensen, J.; Amstrup, B.; Feddersen, H. [Danish Meteorological Institute, Copenhagen (Denmark)] [and others

    2013-08-15

    The MUD project addresses assessment of uncertainties of atmospheric dispersion model predictions, as well as possibilities for optimum presentation to decision makers. Previously, it has not been possible to estimate such uncertainties quantitatively, but merely to calculate the 'most likely' dispersion scenario. However, recent developments in numerical weather prediction (NWP) include probabilistic forecasting techniques, which can be utilised also for long-range atmospheric dispersion models. The ensemble statistical methods developed and applied to NWP models aim at describing the inherent uncertainties of the meteorological model results. These uncertainties stem from e.g. limits in meteorological observations used to initialise meteorological forecast series. By perturbing e.g. the initial state of an NWP model run in agreement with the available observational data, an ensemble of meteorological forecasts is produced from which uncertainties in the various meteorological parameters are estimated, e.g. probabilities for rain. Corresponding ensembles of atmospheric dispersion can now be computed from which uncertainties of predicted radionuclide concentration and deposition patterns can be derived. (Author)

  12. Meteorological uncertainty of atmospheric dispersion model results (MUD)

    International Nuclear Information System (INIS)

    Havskov Soerensen, J.; Amstrup, B.; Feddersen, H.

    2013-08-01

    The MUD project addresses assessment of uncertainties of atmospheric dispersion model predictions, as well as possibilities for optimum presentation to decision makers. Previously, it has not been possible to estimate such uncertainties quantitatively, but merely to calculate the 'most likely' dispersion scenario. However, recent developments in numerical weather prediction (NWP) include probabilistic forecasting techniques, which can be utilised also for long-range atmospheric dispersion models. The ensemble statistical methods developed and applied to NWP models aim at describing the inherent uncertainties of the meteorological model results. These uncertainties stem from e.g. limits in meteorological observations used to initialise meteorological forecast series. By perturbing e.g. the initial state of an NWP model run in agreement with the available observational data, an ensemble of meteorological forecasts is produced from which uncertainties in the various meteorological parameters are estimated, e.g. probabilities for rain. Corresponding ensembles of atmospheric dispersion can now be computed from which uncertainties of predicted radionuclide concentration and deposition patterns can be derived. (Author)

  13. System health monitoring using multiple-model adaptive estimation techniques

    Science.gov (United States)

    Sifford, Stanley Ryan

    Monitoring system health for fault detection and diagnosis by tracking system parameters concurrently with state estimates is approached using a new multiple-model adaptive estimation (MMAE) method. This novel method is called GRid-based Adaptive Parameter Estimation (GRAPE). GRAPE expands existing MMAE methods by using new techniques to sample the parameter space. GRAPE expands on MMAE with the hypothesis that sample models can be applied and resampled without relying on a predefined set of models. GRAPE is initially implemented in a linear framework using Kalman filter models. A more generalized GRAPE formulation is presented using extended Kalman filter (EKF) models to represent nonlinear systems. GRAPE can handle both time invariant and time varying systems as it is designed to track parameter changes. Two techniques are presented to generate parameter samples for the parallel filter models. The first approach is called selected grid-based stratification (SGBS). SGBS divides the parameter space into equally spaced strata. The second approach uses Latin Hypercube Sampling (LHS) to determine the parameter locations and minimize the total number of required models. LHS is particularly useful when the parameter dimensions grow. Adding more parameters does not require the model count to increase for LHS. Each resample is independent of the prior sample set other than the location of the parameter estimate. SGBS and LHS can be used for both the initial sample and subsequent resamples. Furthermore, resamples are not required to use the same technique. Both techniques are demonstrated for both linear and nonlinear frameworks. The GRAPE framework further formalizes the parameter tracking process through a general approach for nonlinear systems. These additional methods allow GRAPE to either narrow the focus to converged values within a parameter range or expand the range in the appropriate direction to track the parameters outside the current parameter range boundary

  14. Rotational acceleration during head impact resulting from different judo throwing techniques.

    Science.gov (United States)

    Murayama, Haruo; Hitosugi, Masahito; Motozawa, Yasuki; Ogino, Masahiro; Koyama, Katsuhiro

    2014-01-01

    Most severe head injuries in judo are reported as acute subdural hematoma. It is thus necessary to examine the rotational acceleration of the head to clarify the mechanism of head injuries. We determined the rotational acceleration of the head when the subject is thrown by judo techniques. One Japanese male judo expert threw an anthropomorphic test device using two throwing techniques, Osoto-gari and Ouchi-gari. Rotational and translational head accelerations were measured with and without an under-mat. For Osoto-gari, peak resultant rotational acceleration ranged from 4,284.2 rad/s(2) to 5,525.9 rad/s(2) and peak resultant translational acceleration ranged from 64.3 g to 87.2 g; for Ouchi-gari, the accelerations respectively ranged from 1,708.0 rad/s(2) to 2,104.1 rad/s(2) and from 120.2 g to 149.4 g. The resultant rotational acceleration did not decrease with installation of an under-mat for both Ouchi-gari and Osoto-gari. We found that head contact with the tatami could result in the peak values of translational and rotational accelerations, respectively. In general, because kinematics of the body strongly affects translational and rotational accelerations of the head, both accelerations should be measured to analyze the underlying mechanism of head injury. As a primary preventative measure, throwing techniques should be restricted to participants demonstrating ability in ukemi techniques to avoid head contact with the tatami.

  15. Evaluation of the functional results after rotator cuff arthroscopic repair with the suture bridge technique

    Directory of Open Access Journals (Sweden)

    Alberto Naoki Miyazaki

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the results of arthroscopic treatment of large and extensive rotator cuff injuries (RCI that involved the supra and infraspinatus muscles using the suture bridge (SB technique. METHODS: Between July 2010 and November 2014, 37 patients with RCI who were treated with SB technique were evaluated. The study included all patients with a minimum follow-up of 12 months who underwent primary surgery of the shoulder. Twenty-four patients were male and 13 were female. The mean age was 60 years (45-75. The dominant side was affected in 32 cases. The most common cause of injury was trauma (18 cases. The mean preoperative motion was 123°, 58°, T11. Through magnetic resonance imaging, 36 fatty degenerations were classified according to Goutallier. Patients underwent rotator cuff repair with SB technique, which consists of using a medial row anchor with two Corkscrew(r fibertape(r or fiberwire(r at the articular margin, associated with lateral fixation without stitch using PushLocks(r or SwiveLocks(r. RESULTS: The mean age was 60 years and mean fatty degeneration was 2.6. The mean range of motion (following the AAOS in the postoperative evaluation was 148° of forward elevation, 55° in lateral rotation and medial rotation in T9. Using the criteria of the University of California at Los Angeles (UCLA, 35 (94% patients had excellent and good results; one (2.7%, fair; and one (2.7%, poor. CONCLUSION: Arthroscopic repair of a large and extensive RCI using SB technique had good and excellent results in 94% of the patients.

  16. Validation of transport models using additive flux minimization technique

    Energy Technology Data Exchange (ETDEWEB)

    Pankin, A. Y.; Kruger, S. E. [Tech-X Corporation, 5621 Arapahoe Ave., Boulder, Colorado 80303 (United States); Groebner, R. J. [General Atomics, San Diego, California 92121 (United States); Hakim, A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States); Kritz, A. H.; Rafiq, T. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States)

    2013-10-15

    A new additive flux minimization technique is proposed for carrying out the verification and validation (V and V) of anomalous transport models. In this approach, the plasma profiles are computed in time dependent predictive simulations in which an additional effective diffusivity is varied. The goal is to obtain an optimal match between the computed and experimental profile. This new technique has several advantages over traditional V and V methods for transport models in tokamaks and takes advantage of uncertainty quantification methods developed by the applied math community. As a demonstration of its efficiency, the technique is applied to the hypothesis that the paleoclassical density transport dominates in the plasma edge region in DIII-D tokamak discharges. A simplified version of the paleoclassical model that utilizes the Spitzer resistivity for the parallel neoclassical resistivity and neglects the trapped particle effects is tested in this paper. It is shown that a contribution to density transport, in addition to the paleoclassical density transport, is needed in order to describe the experimental profiles. It is found that more additional diffusivity is needed at the top of the H-mode pedestal, and almost no additional diffusivity is needed at the pedestal bottom. The implementation of this V and V technique uses the FACETS::Core transport solver and the DAKOTA toolkit for design optimization and uncertainty quantification. The FACETS::Core solver is used for advancing the plasma density profiles. The DAKOTA toolkit is used for the optimization of plasma profiles and the computation of the additional diffusivity that is required for the predicted density profile to match the experimental profile.

  17. Validation of transport models using additive flux minimization technique

    International Nuclear Information System (INIS)

    Pankin, A. Y.; Kruger, S. E.; Groebner, R. J.; Hakim, A.; Kritz, A. H.; Rafiq, T.

    2013-01-01

    A new additive flux minimization technique is proposed for carrying out the verification and validation (V and V) of anomalous transport models. In this approach, the plasma profiles are computed in time dependent predictive simulations in which an additional effective diffusivity is varied. The goal is to obtain an optimal match between the computed and experimental profile. This new technique has several advantages over traditional V and V methods for transport models in tokamaks and takes advantage of uncertainty quantification methods developed by the applied math community. As a demonstration of its efficiency, the technique is applied to the hypothesis that the paleoclassical density transport dominates in the plasma edge region in DIII-D tokamak discharges. A simplified version of the paleoclassical model that utilizes the Spitzer resistivity for the parallel neoclassical resistivity and neglects the trapped particle effects is tested in this paper. It is shown that a contribution to density transport, in addition to the paleoclassical density transport, is needed in order to describe the experimental profiles. It is found that more additional diffusivity is needed at the top of the H-mode pedestal, and almost no additional diffusivity is needed at the pedestal bottom. The implementation of this V and V technique uses the FACETS::Core transport solver and the DAKOTA toolkit for design optimization and uncertainty quantification. The FACETS::Core solver is used for advancing the plasma density profiles. The DAKOTA toolkit is used for the optimization of plasma profiles and the computation of the additional diffusivity that is required for the predicted density profile to match the experimental profile

  18. Reduction of thermal models of buildings: improvement of techniques using meteorological influence models; Reduction de modeles thermiques de batiments: amelioration des techniques par modelisation des sollicitations meteorologiques

    Energy Technology Data Exchange (ETDEWEB)

    Dautin, S.

    1997-04-01

    This work concerns the modeling of thermal phenomena inside buildings for the evaluation of energy exploitation costs of thermal installations and for the modeling of thermal and aeraulic transient phenomena. This thesis comprises 7 chapters dealing with: (1) the thermal phenomena inside buildings and the CLIM2000 calculation code, (2) the ETNA and GENEC experimental cells and their modeling, (3) the techniques of model reduction tested (Marshall`s truncature, Michailesco aggregation method and Moore truncature) with their algorithms and their encoding in the MATRED software, (4) the application of model reduction methods to the GENEC and ETNA cells and to a medium size dual-zone building, (5) the modeling of meteorological influences classically applied to buildings (external temperature and solar flux), (6) the analytical expression of these modeled meteorological influences. The last chapter presents the results of these improved methods on the GENEC and ETNA cells and on a lower inertia building. These new methods are compared to classical methods. (J.S.) 69 refs.

  19. A multi-packer technique for investigating resistance to flow through fractured rock and illustrative results

    International Nuclear Information System (INIS)

    Bourke, P.J.; Rae, J.

    1981-01-01

    A multi-packer technique was used to locate twelve discrete fractures in the lower half of a 200 m deep drill hole in Cornish granite. The resistances to water flows into these fractures both singly and together were measured. Geological explanations of the results obtained were sought by examination of core from the hole. Analysis of the results and the further data needed and now being sought to determine resistance to flow over long distances through the pattern of interconnected fractures are discussed. This information is required for the assessment of the safety of burial of radioactive wastes

  20. Improved ceramic slip casting technique. [application to aircraft model fabrication

    Science.gov (United States)

    Buck, Gregory M. (Inventor); Vasquez, Peter (Inventor)

    1993-01-01

    A primary concern in modern fluid dynamics research is the experimental verification of computational aerothermodynamic codes. This research requires high precision and detail in the test model employed. Ceramic materials are used for these models because of their low heat conductivity and their survivability at high temperatures. To fabricate such models, slip casting techniques were developed to provide net-form, precision casting capability for high-purity ceramic materials in aqueous solutions. In previous slip casting techniques, block, or flask molds made of plaster-of-paris were used to draw liquid from the slip material. Upon setting, parts were removed from the flask mold and cured in a kiln at high temperatures. Casting detail was usually limited with this technique -- detailed parts were frequently damaged upon separation from the flask mold, as the molded parts are extremely delicate in the uncured state, and the flask mold is inflexible. Ceramic surfaces were also marred by 'parting lines' caused by mold separation. This adversely affected the aerodynamic surface quality of the model as well. (Parting lines are invariably necessary on or near the leading edges of wings, nosetips, and fins for mold separation. These areas are also critical for flow boundary layer control.) Parting agents used in the casting process also affected surface quality. These agents eventually soaked into the mold, the model, or flaked off when releasing the case model. Different materials were tried, such as oils, paraffin, and even an algae. The algae released best, but some of it remained on the model and imparted an uneven texture and discoloration on the model surface when cured. According to the present invention, a wax pattern for a shell mold is provided, and an aqueous mixture of a calcium sulfate-bonded investment material is applied as a coating to the wax pattern. The coated wax pattern is then dried, followed by curing to vaporize the wax pattern and leave a shell

  1. RESULTS OF THE USE OF PEEK CAGES IN THE TREATMENT OF BASILAR INVAGINATION BY GOEL TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Luís Eduardo Carelli Teixeira da Silva

    2016-03-01

    Full Text Available ABSTRACT Objective: Analysis of the use of polyetheretherketone (PEEK cages for atlantoaxial facet realignment and distraction for treatment of basilar invagination by Goel technique. Method: Retrospective descriptive statistical analysis of the neurological status, pain, presence of subsidence and bone fusion with the use of PEEK cages in 8 atlantoaxial joints of 4 patients with basilar invagination. All patients were treated with atlantoaxial facet distraction and realignment and subsequent arthrodesis C1-C2 by the technique of Goel modified by the use of PEEK cage. Results: All patients showed improvement in Nurick neurological assessment scale and Visual Analogue Scale (VAS of pain. There were no cases of subsidence, migration, or damage to the vertebral artery during the insertion of the cage. All joints evolved with bone fusion, assessed by dynamic radiographs, and computed tomography. Two patients developed neuropathic pain in dermatome of C2 and one patient had unilateral vertebral artery injury during C2 instrumentation treated with insertion of pedicle screw to control the bleeding. Conclusion: The results of the treatment of basilar invagination by the Goel technique with the use of PEEK cages shown to be effective and safe although further studies are needed to confirm this use.

  2. Modelling of ground penetrating radar data in stratified media using the reflectivity technique

    International Nuclear Information System (INIS)

    Sena, Armando R; Sen, Mrinal K; Stoffa, Paul L

    2008-01-01

    Horizontally layered media are often encountered in shallow exploration geophysics. Ground penetrating radar (GPR) data in these environments can be modelled by techniques that are more efficient than finite difference (FD) or finite element (FE) schemes because the lateral homogeneity of the media allows us to reduce the dependence on the horizontal spatial variables through Fourier transforms on these coordinates. We adapt and implement the invariant embedding or reflectivity technique used to model elastic waves in layered media to model GPR data. The results obtained with the reflectivity and FDTD modelling techniques are in excellent agreement and the effects of the air–soil interface on the radiation pattern are correctly taken into account by the reflectivity technique. Comparison with real wide-angle GPR data shows that the reflectivity technique can satisfactorily reproduce the real GPR data. These results and the computationally efficient characteristics of the reflectivity technique (compared to FD or FE) demonstrate its usefulness in interpretation and possible model-based inversion schemes of GPR data in stratified media

  3. Teaching scientific concepts through simple models and social communication techniques

    International Nuclear Information System (INIS)

    Tilakaratne, K.

    2011-01-01

    For science education, it is important to demonstrate to students the relevance of scientific concepts in every-day life experiences. Although there are methods available for achieving this goal, it is more effective if cultural flavor is also added to the teaching techniques and thereby the teacher and students can easily relate the subject matter to their surroundings. Furthermore, this would bridge the gap between science and day-to-day experiences in an effective manner. It could also help students to use science as a tool to solve problems faced by them and consequently they would feel science is a part of their lives. In this paper, it has been described how simple models and cultural communication techniques can be used effectively in demonstrating important scientific concepts to the students of secondary and higher secondary levels by using two consecutive activities carried out at the Institute of Fundamental Studies (IFS), Sri Lanka. (author)

  4. System Response Analysis and Model Order Reduction, Using Conventional Method, Bond Graph Technique and Genetic Programming

    Directory of Open Access Journals (Sweden)

    Lubna Moin

    2009-04-01

    Full Text Available This research paper basically explores and compares the different modeling and analysis techniques and than it also explores the model order reduction approach and significance. The traditional modeling and simulation techniques for dynamic systems are generally adequate for single-domain systems only, but the Bond Graph technique provides new strategies for reliable solutions of multi-domain system. They are also used for analyzing linear and non linear dynamic production system, artificial intelligence, image processing, robotics and industrial automation. This paper describes a unique technique of generating the Genetic design from the tree structured transfer function obtained from Bond Graph. This research work combines bond graphs for model representation with Genetic programming for exploring different ideas on design space tree structured transfer function result from replacing typical bond graph element with their impedance equivalent specifying impedance lows for Bond Graph multiport. This tree structured form thus obtained from Bond Graph is applied for generating the Genetic Tree. Application studies will identify key issues and importance for advancing this approach towards becoming on effective and efficient design tool for synthesizing design for Electrical system. In the first phase, the system is modeled using Bond Graph technique. Its system response and transfer function with conventional and Bond Graph method is analyzed and then a approach towards model order reduction is observed. The suggested algorithm and other known modern model order reduction techniques are applied to a 11th order high pass filter [1], with different approach. The model order reduction technique developed in this paper has least reduction errors and secondly the final model retains structural information. The system response and the stability analysis of the system transfer function taken by conventional and by Bond Graph method is compared and

  5. Modelling of 3D fractured geological systems - technique and application

    Science.gov (United States)

    Cacace, M.; Scheck-Wenderoth, M.; Cherubini, Y.; Kaiser, B. O.; Bloecher, G.

    2011-12-01

    All rocks in the earth's crust are fractured to some extent. Faults and fractures are important in different scientific and industry fields comprising engineering, geotechnical and hydrogeological applications. Many petroleum, gas and geothermal and water supply reservoirs form in faulted and fractured geological systems. Additionally, faults and fractures may control the transport of chemical contaminants into and through the subsurface. Depending on their origin and orientation with respect to the recent and palaeo stress field as well as on the overall kinematics of chemical processes occurring within them, faults and fractures can act either as hydraulic conductors providing preferential pathways for fluid to flow or as barriers preventing flow across them. The main challenge in modelling processes occurring in fractured rocks is related to the way of describing the heterogeneities of such geological systems. Flow paths are controlled by the geometry of faults and their open void space. To correctly simulate these processes an adequate 3D mesh is a basic requirement. Unfortunately, the representation of realistic 3D geological environments is limited by the complexity of embedded fracture networks often resulting in oversimplified models of the natural system. A technical description of an improved method to integrate generic dipping structures (representing faults and fractures) into a 3D porous medium is out forward. The automated mesh generation algorithm is composed of various existing routines from computational geometry (e.g. 2D-3D projection, interpolation, intersection, convex hull calculation) and meshing (e.g. triangulation in 2D and tetrahedralization in 3D). All routines have been combined in an automated software framework and the robustness of the approach has been tested and verified. These techniques and methods can be applied for fractured porous media including fault systems and therefore found wide applications in different geo-energy related

  6. All-Arthroscopic Revision Eden-Hybinette Procedure for Failed Instability Surgery: Technique and Preliminary Results.

    Science.gov (United States)

    Giannakos, Antonios; Vezeridis, Peter S; Schwartz, Daniel G; Jany, Richard; Lafosse, Laurent

    2017-01-01

    To describe the technique of an all-arthroscopic Eden-Hybinette procedure in the revision setting for treatment of a failed instability procedure, particularly after failed Latarjet, as well as to present preliminary results of this technique. Between 2007 and 2011, 18 shoulders with persistent instability after failed instability surgery were treated with an arthroscopic Eden-Hybinette technique using an autologous bicortical iliac crest bone graft. Of 18 patients, 12 (9 men, 3 women) were available for follow-up. The average follow-up was 28.8 months (range, 15 to 60 months). A Latarjet procedure was performed as an index surgery in 10 patients (83%). Two patients (17%) had a prior arthroscopic Bankart repair. Eight patients (67%) obtained a good or excellent result, whereas 4 patients (33%) reported a fair or poor result. Seven patients (58%) returned to sport activities. A positive apprehension test persisted in 5 patients (42%), including 2 patients (17%) with recurrent subluxations. The Rowe score increased from 30.00 to 78.33 points (P Instability Index score showed a good result of 28.71% (603 points). The average anterior flexion was 176° (range, 150° to 180°), and the average external rotation was 66° (range, 0° to 90°). Two patients (16.67%) showed a progression of glenohumeral osteoarthritic changes, with each patient increasing by one stage in the Samilson-Prieto classification. All 4 patients (33%) with a fair or poor result had a nonunion identified on postoperative computed tomography scan. An all-arthroscopic Eden-Hybinette procedure in the revision setting for failed instability surgery, although technically demanding, is a safe, effective, and reproducible technique. Although the learning curve is considerable, this procedure offers all the advantages of arthroscopic surgery and allows reconstruction of glenoid defects and restoration of shoulder stability in this challenging patient population. In our hands, this procedure yields good

  7. Monte Carlo technique for very large ising models

    Science.gov (United States)

    Kalle, C.; Winkelmann, V.

    1982-08-01

    Rebbi's multispin coding technique is improved and applied to the kinetic Ising model with size 600*600*600. We give the central part of our computer program (for a CDC Cyber 76), which will be helpful also in a simulation of smaller systems, and describe the other tricks necessary to go to large lattices. The magnetization M at T=1.4* T c is found to decay asymptotically as exp(-t/2.90) if t is measured in Monte Carlo steps per spin, and M( t = 0) = 1 initially.

  8. Validation techniques of agent based modelling for geospatial simulations

    Directory of Open Access Journals (Sweden)

    M. Darvishi

    2014-10-01

    Full Text Available One of the most interesting aspects of modelling and simulation study is to describe the real world phenomena that have specific properties; especially those that are in large scales and have dynamic and complex behaviours. Studying these phenomena in the laboratory is costly and in most cases it is impossible. Therefore, Miniaturization of world phenomena in the framework of a model in order to simulate the real phenomena is a reasonable and scientific approach to understand the world. Agent-based modelling and simulation (ABMS is a new modelling method comprising of multiple interacting agent. They have been used in the different areas; for instance, geographic information system (GIS, biology, economics, social science and computer science. The emergence of ABM toolkits in GIS software libraries (e.g. ESRI’s ArcGIS, OpenMap, GeoTools, etc for geospatial modelling is an indication of the growing interest of users to use of special capabilities of ABMS. Since ABMS is inherently similar to human cognition, therefore it could be built easily and applicable to wide range applications than a traditional simulation. But a key challenge about ABMS is difficulty in their validation and verification. Because of frequent emergence patterns, strong dynamics in the system and the complex nature of ABMS, it is hard to validate and verify ABMS by conventional validation methods. Therefore, attempt to find appropriate validation techniques for ABM seems to be necessary. In this paper, after reviewing on Principles and Concepts of ABM for and its applications, the validation techniques and challenges of ABM validation are discussed.

  9. Validation techniques of agent based modelling for geospatial simulations

    Science.gov (United States)

    Darvishi, M.; Ahmadi, G.

    2014-10-01

    One of the most interesting aspects of modelling and simulation study is to describe the real world phenomena that have specific properties; especially those that are in large scales and have dynamic and complex behaviours. Studying these phenomena in the laboratory is costly and in most cases it is impossible. Therefore, Miniaturization of world phenomena in the framework of a model in order to simulate the real phenomena is a reasonable and scientific approach to understand the world. Agent-based modelling and simulation (ABMS) is a new modelling method comprising of multiple interacting agent. They have been used in the different areas; for instance, geographic information system (GIS), biology, economics, social science and computer science. The emergence of ABM toolkits in GIS software libraries (e.g. ESRI's ArcGIS, OpenMap, GeoTools, etc) for geospatial modelling is an indication of the growing interest of users to use of special capabilities of ABMS. Since ABMS is inherently similar to human cognition, therefore it could be built easily and applicable to wide range applications than a traditional simulation. But a key challenge about ABMS is difficulty in their validation and verification. Because of frequent emergence patterns, strong dynamics in the system and the complex nature of ABMS, it is hard to validate and verify ABMS by conventional validation methods. Therefore, attempt to find appropriate validation techniques for ABM seems to be necessary. In this paper, after reviewing on Principles and Concepts of ABM for and its applications, the validation techniques and challenges of ABM validation are discussed.

  10. Clinical Results of Flexor Tendon Repair in Zone II Using a six Strand Double Loop Technique.

    Science.gov (United States)

    Savvidou, Christiana; Tsai, Tsu-Min

    2015-06-01

    The purpose of this study is to report the clinical results after repair of flexor tendon zone II injuries utilizing a 6-strand double-loop technique and early post-operative active rehabilitation. We retrospectively reviewed 22 patients involving 51 cases with zone II flexor tendon repair using a six strand double loop technique from September 1996 to December 2012. Most common mechanism of injuries was sharp lacerations (86.5 %). Tendon injuries occurred equally in manual and non-manual workers and were work-related in 33 % of the cases. The Strickland score for active range of motion (ROM) postoperatively was excellent and good in the majority of the cases (81 %). The rupture rate was 1.9 %. The six strand double loop technique for Zone II flexor tendon repair leads to good and excellent motion in the majority of patients and low re- rupture rate. It is clinically effective and allows for early postoperative active rehabilitation.

  11. A fully blanketed early B star LTE model atmosphere using an opacity sampling technique

    International Nuclear Information System (INIS)

    Phillips, A.P.; Wright, S.L.

    1980-01-01

    A fully blanketed LTE model of a stellar atmosphere with Tsub(e) = 21914 K (thetasub(e) = 0.23), log g = 4 is presented. The model includes an explicit representation of the opacity due to the strongest lines, and uses a statistical opacity sampling technique to represent the weaker line opacity. The sampling technique is subjected to several tests and the model is compared with an atmosphere calculated using the line-distribution function method. The limitations of the distribution function method and the particular opacity sampling method used here are discussed in the light of the results obtained. (author)

  12. Identification techniques for phenomenological models of hysteresis based on the conjugate gradient method

    International Nuclear Information System (INIS)

    Andrei, Petru; Oniciuc, Liviu; Stancu, Alexandru; Stoleriu, Laurentiu

    2007-01-01

    An identification technique for the parameters of phenomenological models of hysteresis is presented. The basic idea of our technique is to set up a system of equations for the parameters of the model as a function of known quantities on the major or minor hysteresis loops (e.g. coercive force, susceptibilities at various points, remanence), or other magnetization curves. This system of equations can be either over or underspecified and is solved by using the conjugate gradient method. Numerical results related to the identification of parameters in the Energetic, Jiles-Atherton, and Preisach models are presented

  13. Application of Soft Computing Techniques and Multiple Regression Models for CBR prediction of Soils

    Directory of Open Access Journals (Sweden)

    Fatimah Khaleel Ibrahim

    2017-08-01

    Full Text Available The techniques of soft computing technique such as Artificial Neutral Network (ANN have improved the predicting capability and have actually discovered application in Geotechnical engineering. The aim of this research is to utilize the soft computing technique and Multiple Regression Models (MLR for forecasting the California bearing ratio CBR( of soil from its index properties. The indicator of CBR for soil could be predicted from various soils characterizing parameters with the assist of MLR and ANN methods. The data base that collected from the laboratory by conducting tests on 86 soil samples that gathered from different projects in Basrah districts. Data gained from the experimental result were used in the regression models and soft computing techniques by using artificial neural network. The liquid limit, plastic index , modified compaction test and the CBR test have been determined. In this work, different ANN and MLR models were formulated with the different collection of inputs to be able to recognize their significance in the prediction of CBR. The strengths of the models that were developed been examined in terms of regression coefficient (R2, relative error (RE% and mean square error (MSE values. From the results of this paper, it absolutely was noticed that all the proposed ANN models perform better than that of MLR model. In a specific ANN model with all input parameters reveals better outcomes than other ANN models.

  14. Laparoscopic anterior resection: new anastomosis technique in a pig model.

    Science.gov (United States)

    Bedirli, Abdulkadir; Yucel, Deniz; Ekim, Burcu

    2014-01-01

    Bowel anastomosis after anterior resection is one of the most difficult tasks to perform during laparoscopic colorectal surgery. This study aims to evaluate a new feasible and safe intracorporeal anastomosis technique after laparoscopic left-sided colon or rectum resection in a pig model. The technique was evaluated in 5 pigs. The OrVil device (Covidien, Mansfield, Massachusetts) was inserted into the anus and advanced proximally to the rectum. A 0.5-cm incision was made in the sigmoid colon, and the 2 sutures attached to its delivery tube were cut. After the delivery tube was evacuated through the anus, the tip of the anvil was removed through the perforation. The sigmoid colon was transected just distal to the perforation with an endoscopic linear stapler. The rectosigmoid segment to be resected was removed through the anus with a grasper, and distal transection was performed. A 25-mm circular stapler was inserted and combined with the anvil, and end-to-side intracorporeal anastomosis was then performed. We performed the technique in 5 pigs. Anastomosis required an average of 12 minutes. We observed that the proximal and distal donuts were completely removed in all pigs. No anastomotic air leakage was observed in any of the animals. This study shows the efficacy and safety of intracorporeal anastomosis with the OrVil device after laparoscopic anterior resection.

  15. The results of surgical treatment of oviductal infertility with use of microsurgical technique

    International Nuclear Information System (INIS)

    Cislo, M.; Murawski, M.; Palczynski, B.

    1993-01-01

    40 women were operated on infertility due to oviductal factor. This kind of infertility has been previously diagnosed by hysterosalpingography examination and then verified in 22 cases (55%) by laparoscopy combined with chromotubation. The operations were carried out with use of microsurgical technique and instruments. At the same time the prophylactics of postoperative intraperitoneal adhesions was applied. Seven pregnancies were obtained, that makes 17.5% of success. It is an outcome comparable with results presented by many other world centers of gynecological microsurgery. (author)

  16. Modelling techniques for predicting the long term consequences of radiation on natural aquatic populations

    International Nuclear Information System (INIS)

    Wallis, I.G.

    1978-01-01

    The purpose of this working paper is to describe modelling techniques for predicting the long term consequences of radiation on natural aquatic populations. Ideally, it would be possible to use aquatic population models: (1) to predict changes in the health and well-being of all aquatic populations as a result of changing the composition, amount and location of radionuclide discharges; (2) to compare the effects of steady, fluctuating and accidental releases of radionuclides; and (3) to evaluate the combined impact of the discharge of radionuclides and other wastes, and natural environmental stresses on aquatic populations. At the onset it should be stated that there is no existing model which can achieve this ideal performance. However, modelling skills and techniques are available to develop useful aquatic population models. This paper discusses the considerations involved in developing these models and briefly describes the various types of population models which have been developed to date

  17. First results in the use of sterile insect technique against Trialeurodes vaporariorum (Homoptera: Aleyroididae) in greenhouses

    International Nuclear Information System (INIS)

    Calvitti, M.; Remotti, P.C.; Pasquali, A.; Cirio, U.

    1998-01-01

    Trials for the evaluation of the effectiveness of the sterile insect technique for the suppression of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), both in cage and in greenhouse conditions are described. The results show a significant reduction of the reproductive capacity of the untreated whitefly populations interacting with sterile insects. Untreated whiteflies, co-existing in a mixed population together with sterile insects, attained less than the half (44%) of their potential reproductive capacity. This trend was also evident in the cage test where the untreated whitefly population, crossed with the sterile whiteflies, increased without exceeding 2/3 of the density recorded in the control cages. These results may be based on 2 joint sterile insect technique effects: primarily a drastic reduction of the progeny of normal untreated females, when mating with sterile males, carriers of dominant lethal mutations, and secondarily a progressive reduction of the females in the population due to an increasing rate of unsuccessful matings resulting in a condition of forced arrhenotoky. No deleterious effects, on plant health and fruit quality, were observed on plants exposed to high sterile whitefly pressures

  18. Application of HEART technique in health care system and accuracy of its results

    Directory of Open Access Journals (Sweden)

    Mohammad Beiruti

    2016-12-01

    Full Text Available Introduction: Human error is considered as a crucial challenge in occupational settings. Health care system is amongst occupational environments with high rate of human errors. Numerous preceding studies noted that more than 2/3 of medical errors are preventable. Accordingly, different methods are suggested to evaluate human errors, especially in nuclear industries. The aim of this study was to evaluate the application and accuracy of HEART technique in medical health system. Material and Method:  This qualitative study was conducted in surgical intensive care units of a hospital in Shiraz city. All nurses recorded errors were categorized regarding the given tasks and then all tasks were ranked based on the number of errors. The probability of nurses’ tasks error was estimated through AHP-HEART method and the resultant ranking was compared with the recorded errors. Additionally, the prioritization of contributing factors to errors, determined by AHP and AHP-HEART methods, was compared employing Pearson statistical test. Results: Based on the results, there was a concordance in the rate of nurses’ error determined by HEART method and the recorded errors. However, no significant correlation was between errors contributing factors determined by AHP and AHP-HEART methods. Conclusion: This study suggested that although HEART technique was successful to rank the tasks considering the magnitude of error probability, but the coefficients of error producing conditions should be customized for nurses’ tasks in order to provide appropriate control measures.

  19. Transtemporal amygdalohippocampectomy: a novel minimally-invasive technique with optimal clinical results and low cost

    Directory of Open Access Journals (Sweden)

    Juan Antonio Castro Flores

    Full Text Available ABSTRACT Mesial temporal sclerosis creates a focal epileptic syndrome that usually requires surgical resection of mesial temporal structures. Objective: To describe a novel operative technique for treatment of temporal lobe epilepsy and its clinical results. Methods: Prospective case-series at a single institution, performed by a single surgeon, from 2006 to 2012. A total of 120 patients were submitted to minimally-invasive keyhole transtemporal amygdalohippocampectomy. Results: Of the patients, 55% were male, and 85% had a right-sided disease. The first 70 surgeries had a mean surgical time of 2.51 hours, and the last 50 surgeries had a mean surgical time of 1.62 hours. There was 3.3% morbidity, and 5% mild temporal muscle atrophy. There was no visual field impairment. On the Engel Outcome Scale at the two-year follow-up, 71% of the patients were Class I, 21% were Class II, and 6% were Class III. Conclusion: This novel technique is feasible and reproducible, with optimal clinical results.

  20. Comparison of Analysis and Spectral Nudging Techniques for Dynamical Downscaling with the WRF Model over China

    OpenAIRE

    Ma, Yuanyuan; Yang, Yi; Mai, Xiaoping; Qiu, Chongjian; Long, Xiao; Wang, Chenghai

    2016-01-01

    To overcome the problem that the horizontal resolution of global climate models may be too low to resolve features which are important at the regional or local scales, dynamical downscaling has been extensively used. However, dynamical downscaling results generally drift away from large-scale driving fields. The nudging technique can be used to balance the performance of dynamical downscaling at large and small scales, but the performances of the two nudging techniques (analysis nudging and s...

  1. A Continuous Dynamic Traffic Assignment Model From Plate Scanning Technique

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, A.; Gallego, I.; Sanchez-Cambronero, S.; Ruiz-Ripoll, L.; Barba, R.M.

    2016-07-01

    This paper presents a methodology for the dynamic estimation of traffic flows on all links of a network from observable field data assuming the first-in-first-out (FIFO) hypothesis. The traffic flow intensities recorded at the exit of the scanned links are propagated to obtain the flow waves on unscanned links. For that, the model calculates the flow-cost functions through information registered with the plate scanning technique. The model also responds to the concern about the parameter quality of flow-cost functions to replicate the real traffic flow behaviour. It includes a new algorithm for the adjustment of the parameter values to link characteristics when its quality is questionable. For that, it is necessary the a priori study of the location of the scanning devices to identify all path flows and to measure travel times in all links. A synthetic network is used to illustrate the proposed method and to prove its usefulness and feasibility. (Author)

  2. Korean national QPE technique development: Analysis of current QPE results and future plan

    Science.gov (United States)

    Cha, Joo Wan

    2013-04-01

    Korea Meteorological Administration(KMA) has developed a Real-time ADjusted Radar-AWS (Automatic Weather Station) Rainrate (RAD-RAR) system using eleven radars over the South Korea. The procedure of the RAD-RAR system in real time consists of four steps: 1) the quality control of volumetric reflectivity for each radar, 2) the computation of the every 10-min rain gauge rainfall within each radar, 3) the real time (10 min-updated) rainfall estimation by the Z-R relationship minimizing the difference between the 1.5-km constant altitude plan precipitation indicator and rain gauge rainfall based on Window Probability Matching Method(WPMM) and by the real-time bias correction of RAD-RAR conducted at every 10 minutes for each radar by making the bias, and 4) the composition of the 11-radar estimated rainfall data. In addition, a local gauge correction method applies for RAD-RAR system. Therefore, the correlation coefficient of R2 = 0.81 is obtained between the daily accumulated observed and RAD-RAR estimated rainfall in 2012. We like to develop a new QPE system using the multi-sensor(radar, rain gauge, numerical model output, and lightning) data for newly improving Korean national QPE system. We made the prototype QPE system in 2012 and improve the detail techniques now. In the future, the new high performance QPE system will include a dual polarization radar observation technique for providing more accurate and valuable national QPE data

  3. Establishment of 60Co dose calibration curve using fluorescent in situ hybridization assay technique: Result of preliminary study

    International Nuclear Information System (INIS)

    Rahimah Abdul Rahim; Noriah Jamal; Noraisyah Mohd Yusof; Juliana Mahamad Napiah; Nelly Bo Nai Lee

    2010-01-01

    This study aims at establishing an in-vitro 60 Co dose calibration curve using Fluorescent In-Situ Hybridization assay technique for the Malaysian National Bio dosimetry Laboratory. Blood samples collected from a female healthy donor were irradiated with several doses of 60 Co radiation. Following culturing of lymphocytes, microscopic slides are prepared, denatured and hybridized. The frequencies of translocation are estimated in the metaphases. A calibration curve was then generated using a regression technique. It shows a good fit to a linear-quadratic model. The results of this study might be useful in estimating absorbed dose for the individual exposed to ionizing radiation retrospectively. This information may be useful as a guide for medical treatment for the assessment of possible health consequences. (author)

  4. Techniques to Access Databases and Integrate Data for Hydrologic Modeling

    International Nuclear Information System (INIS)

    Whelan, Gene; Tenney, Nathan D.; Pelton, Mitchell A.; Coleman, Andre M.; Ward, Duane L.; Droppo, James G.; Meyer, Philip D.; Dorow, Kevin E.; Taira, Randal Y.

    2009-01-01

    This document addresses techniques to access and integrate data for defining site-specific conditions and behaviors associated with ground-water and surface-water radionuclide transport applicable to U.S. Nuclear Regulatory Commission reviews. Environmental models typically require input data from multiple internal and external sources that may include, but are not limited to, stream and rainfall gage data, meteorological data, hydrogeological data, habitat data, and biological data. These data may be retrieved from a variety of organizations (e.g., federal, state, and regional) and source types (e.g., HTTP, FTP, and databases). Available data sources relevant to hydrologic analyses for reactor licensing are identified and reviewed. The data sources described can be useful to define model inputs and parameters, including site features (e.g., watershed boundaries, stream locations, reservoirs, site topography), site properties (e.g., surface conditions, subsurface hydraulic properties, water quality), and site boundary conditions, input forcings, and extreme events (e.g., stream discharge, lake levels, precipitation, recharge, flood and drought characteristics). Available software tools for accessing established databases, retrieving the data, and integrating it with models were identified and reviewed. The emphasis in this review was on existing software products with minimal required modifications to enable their use with the FRAMES modeling framework. The ability of four of these tools to access and retrieve the identified data sources was reviewed. These four software tools were the Hydrologic Data Acquisition and Processing System (HDAPS), Integrated Water Resources Modeling System (IWRMS) External Data Harvester, Data for Environmental Modeling Environmental Data Download Tool (D4EM EDDT), and the FRAMES Internet Database Tools. The IWRMS External Data Harvester and the D4EM EDDT were identified as the most promising tools based on their ability to access and

  5. Techniques to Access Databases and Integrate Data for Hydrologic Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Whelan, Gene; Tenney, Nathan D.; Pelton, Mitchell A.; Coleman, Andre M.; Ward, Duane L.; Droppo, James G.; Meyer, Philip D.; Dorow, Kevin E.; Taira, Randal Y.

    2009-06-17

    This document addresses techniques to access and integrate data for defining site-specific conditions and behaviors associated with ground-water and surface-water radionuclide transport applicable to U.S. Nuclear Regulatory Commission reviews. Environmental models typically require input data from multiple internal and external sources that may include, but are not limited to, stream and rainfall gage data, meteorological data, hydrogeological data, habitat data, and biological data. These data may be retrieved from a variety of organizations (e.g., federal, state, and regional) and source types (e.g., HTTP, FTP, and databases). Available data sources relevant to hydrologic analyses for reactor licensing are identified and reviewed. The data sources described can be useful to define model inputs and parameters, including site features (e.g., watershed boundaries, stream locations, reservoirs, site topography), site properties (e.g., surface conditions, subsurface hydraulic properties, water quality), and site boundary conditions, input forcings, and extreme events (e.g., stream discharge, lake levels, precipitation, recharge, flood and drought characteristics). Available software tools for accessing established databases, retrieving the data, and integrating it with models were identified and reviewed. The emphasis in this review was on existing software products with minimal required modifications to enable their use with the FRAMES modeling framework. The ability of four of these tools to access and retrieve the identified data sources was reviewed. These four software tools were the Hydrologic Data Acquisition and Processing System (HDAPS), Integrated Water Resources Modeling System (IWRMS) External Data Harvester, Data for Environmental Modeling Environmental Data Download Tool (D4EM EDDT), and the FRAMES Internet Database Tools. The IWRMS External Data Harvester and the D4EM EDDT were identified as the most promising tools based on their ability to access and

  6. Minimally invasive treatment of trochanteric fractures with intramedullary nails. Technique and results.

    Science.gov (United States)

    Todor, Adrian; Pojar, Adina; Lucaciu, Dan

    2013-01-01

    The aim of the study was to evaluate the results of minimally invasive treatment of trochanteric fractures with the use of intramedullary nails. From September 2010 to September 2012 we treated 21 patients with pertrochanteric fractures by a minimally invasive technique using the Gamma 3 (Stryker, Howmedica) nail. There were 13 females and 8 men with a mean age of 74.1 years, ranging from 58 to 88 years. Fractures were classified as being stable (AO type 31-A1) in 5 cases and unstable (AO type 31-A2 and A3) in the rest of 16 cases. Patients were reviewed at 6 weeks and 3 months postoperatively. Mean surgery time was 46.8 minutes and mean hospital stay was 14.9 days. No patients required blood transfusions. During the hospital stay all the patients were mobilized with weight bearing as tolerated. All patients were available for review at 6 weeks, and 2 were lost to the 3 months follow up. 16 patients regained the previous level of activity. This minimally invasive technique using a gamma nail device for pertrochanteric fractures gives reliable good results with excellent preservation of hip function.

  7. Improving default risk prediction using Bayesian model uncertainty techniques.

    Science.gov (United States)

    Kazemi, Reza; Mosleh, Ali

    2012-11-01

    Credit risk is the potential exposure of a creditor to an obligor's failure or refusal to repay the debt in principal or interest. The potential of exposure is measured in terms of probability of default. Many models have been developed to estimate credit risk, with rating agencies dating back to the 19th century. They provide their assessment of probability of default and transition probabilities of various firms in their annual reports. Regulatory capital requirements for credit risk outlined by the Basel Committee on Banking Supervision have made it essential for banks and financial institutions to develop sophisticated models in an attempt to measure credit risk with higher accuracy. The Bayesian framework proposed in this article uses the techniques developed in physical sciences and engineering for dealing with model uncertainty and expert accuracy to obtain improved estimates of credit risk and associated uncertainties. The approach uses estimates from one or more rating agencies and incorporates their historical accuracy (past performance data) in estimating future default risk and transition probabilities. Several examples demonstrate that the proposed methodology can assess default probability with accuracy exceeding the estimations of all the individual models. Moreover, the methodology accounts for potentially significant departures from "nominal predictions" due to "upsetting events" such as the 2008 global banking crisis. © 2012 Society for Risk Analysis.

  8. Survey of NDT techniques, services, qualifications and certification of NDT personnel-preliminary results

    International Nuclear Information System (INIS)

    Aleta, C.R.; Kinilitan, V.E.; Lailo, R.M.

    1987-01-01

    This paper presented the results of a survey conducted to determine the profile of the NDT industry including its problems. A questionnaire designed in three parts 1) present practices on qualification and certification, 2) NDT equipment and 3) services and problems in NDT. Of the 36 firms contacted only 20 responded. Results indicated the following: a) most firms are engaged in four (4) main techniques, RT, UT, MT and PT. Only 2 indicated capability of ET. b) level III personnel are relatively few in number, c) most firms allow the ASNT recommendation as a basis for their qualifications and certification and are in favor of standardization of the qualification and certification process and supportive of a national center for training of NDT personnel and d) most firms perceived the lack of adequate repair/maintenance skills/facilities, followed by high cost of equipment and the lack of national standard for qualification and certification. (ELC)

  9. Optimizing Availability of a Framework in Series Configuration Utilizing Markov Model and Monte Carlo Simulation Techniques

    Directory of Open Access Journals (Sweden)

    Mansoor Ahmed Siddiqui

    2017-06-01

    Full Text Available This research work is aimed at optimizing the availability of a framework comprising of two units linked together in series configuration utilizing Markov Model and Monte Carlo (MC Simulation techniques. In this article, effort has been made to develop a maintenance model that incorporates three distinct states for each unit, while taking into account their different levels of deterioration. Calculations are carried out using the proposed model for two distinct cases of corrective repair, namely perfect and imperfect repairs, with as well as without opportunistic maintenance. Initially, results are accomplished using an analytical technique i.e., Markov Model. Validation of the results achieved is later carried out with the help of MC Simulation. In addition, MC Simulation based codes also work well for the frameworks that follow non-exponential failure and repair rates, and thus overcome the limitations offered by the Markov Model.

  10. Comparison of different uncertainty techniques in urban stormwater quantity and quality modelling

    DEFF Research Database (Denmark)

    Dotto, C. B.; Mannina, G.; Kleidorfer, M.

    2012-01-01

    -UA), an approach based on a multi-objective auto-calibration (a multialgorithm, genetically adaptive multiobjective method, AMALGAM) and a Bayesian approach based on a simplified Markov Chain Monte Carlo method (implemented in the software MICA). To allow a meaningful comparison among the different uncertainty...... techniques, common criteria have been set for the likelihood formulation, defining the number of simulations, and the measure of uncertainty bounds. Moreover, all the uncertainty techniques were implemented for the same case study, in which the same stormwater quantity and quality model was used alongside...... the same dataset. The comparison results for a well-posed rainfall/runoff model showed that the four methods provide similar probability distributions of model parameters, and model prediction intervals. For ill-posed water quality model the differences between the results were much wider; and the paper...

  11. Application of decision tree technique to sensitivity analysis for results of radionuclide migration calculations. Research documents

    International Nuclear Information System (INIS)

    Nakajima, Kunihiko; Makino, Hitoshi

    2005-03-01

    Uncertainties are always present in the parameters used for the nuclide migration analysis in the geological disposal system. These uncertainties affect the result of such analyses, e.g., and the identification of dominant nuclides. It is very important to identify the parameters causing the significant impact on the results, and to investigate the influence of identified parameters in order to recognize R and D items with respect to the development of geological disposal system and understanding of the system performance. In our study, the decision tree analysis technique was examined in the sensitivity analysis as a method for investigation of the influences of the parameters and for complement existing sensitivity analysis. As a result, results obtained from Monte Carlo simulation with parameter uncertainties could be distinguished with not only important parameters but also with their quantitative conditions (e.g., ranges of parameter values). Furthermore, information obtained from the decision tree analysis could be used 1) to categorize the results obtained from the nuclide migration analysis for a given parameter set, 2) to show prospective effect of reduction to parameter uncertainties on the results. (author)

  12. [Endoscopic calcaneoplasty (ECP) in Haglund's syndrome. Indication, surgical technique, surgical findings and results].

    Science.gov (United States)

    Jerosch, J; Sokkar, S; Dücker, M; Donner, A

    2012-06-01

    Posterior calcaneal exostosis treatment modalities have given rise to many controversial opinions. After failure of the conservative treatment, surgical bursectomy and resection of the calcaneal exostosis are indicated by many authors. But clinical studies also show a high rate of unsatisfactory results with a relative high incidence of complications. The minimally invasive surgical technique by an endoscopic calcaneoplasty (ECP) could be an option to overcome some of these problems. Between 1999 und 2010 we operated 164 patients with an age range between 16 and 67 years, 81 males and 83 females. The radiological examination prior to surgery documented in all cases a posterior superior calcaneal exostosis that showed friction to the Achilles tendon. All patients included in the study had no clinical varus of the hind foot, nor cavus deformities. All patients had undergone a trial of conservative treatment for at least 6 months and did not show a positive response. The average follow-up was 46.3 (range: 8-120) months. According to the Ogilvie-Harris score 71 patients presented good and 84 patients excellent results, while 5 patients showed fair results, and 4 patients only poor results. All the post-operative radiographs showed sufficient resection of the calcaneal spur. In 61 patients the preoperative MRI showed a partial rupture of the Achilles tendon close to the insertion side. In no case could we observe a complete tear at the time of follow-up. Only minor postoperative complications were observed. In many patients we could observe a chondral layer at the posterior aspect of the calcaneus. Close to the intersion the Achilles tendon showed also in many patients a chondroide metaplasia. ECP is an effective and minimally invasive procedure for the treatment of patients with calcaneal exostosis. After a short learning curve the endoscopic exposure is superior to the open technique, has less morbidity, less operating time, and nearly no complications. Moreover, the

  13. Application of separable parameter space techniques to multi-tracer PET compartment modeling

    International Nuclear Information System (INIS)

    Zhang, Jeff L; Michael Morey, A; Kadrmas, Dan J

    2016-01-01

    Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg–Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models. (paper)

  14. Preliminary Experimental Results on the Technique of Artificial River Replenishment to Mitigate Sediment Loss Downstream Dams

    Science.gov (United States)

    Franca, M. J.; Battisacco, E.; Schleiss, A. J.

    2014-12-01

    The transport of sediments by water throughout the river basins, from the steep slopes of the upstream regions to the sea level, is recognizable important to keep the natural conditions of rivers with a role on their ecology processes. Over the last decades, a reduction on the supply of sand and gravel has been observed downstream dams existing in several alpine rivers. Many studies highlight that the presence of a dam strongly modifies the river behavior in the downstream reach, in terms of morphology and hydrodynamics, with consequences on local ecology. Sediment deficit, bed armoring, river incision and bank instability are the main effects which affect negatively the aquatic habitats and the water quality. One of the proposed techniques to solve the problem of sediment deficit downstream dams, already adopted in few Japanese and German rivers although on an unsatisfactory fashion, is the artificial replenishment of these. Generally, it was verified that the erosion of the replenishments was not satisfactory and the transport rate was not enough to move the sediments to sufficient downstream distances. In order to improve and to provide an engineering answer to make this technique more applicable, a series of laboratory tests are ran as preparatory study to understand the hydrodynamics of the river flow when the replenishment technique is applied. Erodible volumes, with different lengths and submergence conditions, reproducing sediment replenishments volumes, are positioned along a channel bank. Different geometrical combinations of erodible sediment volumes are tested as well on the experimental flume. The first results of the experimental research, concerning erosion time evolution, the influence of discharge and the distance travelled by the eroded sediments, will be presented and discussed.

  15. Comparison of NDT techniques to evaluate CFRP. Results obtained in a MAIzfp round robin test

    Energy Technology Data Exchange (ETDEWEB)

    Grosse, Christian U. [Technische Univ. Muenchen (Germany). Chair of Non-destructive Testing; Goldammer, Matthias; Grager, Jan-Carl [Siemens AG Corporate Technology, Muenchen (Germany); and others

    2016-10-01

    Fiber reinforced polymeric materials are used for lightweight constructions and are an integral part of cars, airplanes or rotor blades of wind turbines. Nondestructive testing (NDT) methods play an increasing role concerning the manufacturing process and the inspection during lifetime. The selection of the best NDT technique for a certain application depends - of course - on many factors including the type, position and size of the defect to be detected but also on secondary issues like accessibility, automation, testing costs, reliability and resolution to mention only some. For the more technical-scientific part of these issues, the determination of the probability of detection (PoD) plays a significant role. Early in the design process questions should be raised concerning the probability with which certain attribute of interest (a defect that has an effect on the structural behavior) can be detected (and localized) in a certain construction. Several defect types have been identified to be critical like impact damages, undulations and porosity. Test samples out of differently processed Carbon Fiber-Reinforced Polymers (CFRP) as used in the automotive or aeronautical industry have been produced including defects of different type and size. In order to determine the PoD and to check whether a technique is applicable the different partners applied a broad variety of selected NDT techniques including Micro CT, Ultrasound (including phased-array and air-coupled UT), Active Thermography, Eddy Current, Vibration and Visual Analysis and Local Acoustic Resonance Spectroscopy (LARS). The presentation will summarize some of the results of the experiments and ongoing data analysis.

  16. Comparison of NDT techniques to evaluate CFRP. Results obtained in a MAIzfp round robin test

    International Nuclear Information System (INIS)

    Grosse, Christian U.

    2016-01-01

    Fiber reinforced polymeric materials are used for lightweight constructions and are an integral part of cars, airplanes or rotor blades of wind turbines. Nondestructive testing (NDT) methods play an increasing role concerning the manufacturing process and the inspection during lifetime. The selection of the best NDT technique for a certain application depends - of course - on many factors including the type, position and size of the defect to be detected but also on secondary issues like accessibility, automation, testing costs, reliability and resolution to mention only some. For the more technical-scientific part of these issues, the determination of the probability of detection (PoD) plays a significant role. Early in the design process questions should be raised concerning the probability with which certain attribute of interest (a defect that has an effect on the structural behavior) can be detected (and localized) in a certain construction. Several defect types have been identified to be critical like impact damages, undulations and porosity. Test samples out of differently processed Carbon Fiber-Reinforced Polymers (CFRP) as used in the automotive or aeronautical industry have been produced including defects of different type and size. In order to determine the PoD and to check whether a technique is applicable the different partners applied a broad variety of selected NDT techniques including Micro CT, Ultrasound (including phased-array and air-coupled UT), Active Thermography, Eddy Current, Vibration and Visual Analysis and Local Acoustic Resonance Spectroscopy (LARS). The presentation will summarize some of the results of the experiments and ongoing data analysis.

  17. Radiation techniques used in patients with breast cancer: Results of a survey in Spain

    Science.gov (United States)

    Algara, Manuel; Arenas, Meritxell; De las Peñas Eloisa Bayo, Dolores; Muñoz, Julia; Carceller, José Antonio; Salinas, Juan; Moreno, Ferran; Martínez, Francisco; González, Ezequiel; Montero, Ángel

    2012-01-01

    Aim To evaluate the resources and techniques used in the irradiation of patients with breast cancer after lumpectomy or mastectomy and the status of implementation of new techniques and therapeutic schedules in our country. Background The demand for cancer care has increased among the Spanish population, as long as cancer treatment innovations have proliferated. Radiation therapy in breast cancer has evolved exponentially in recent years with the implementation of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, image guided radiotherapy and hypofractionation. Material and Methods An original survey questionnaire was sent to institutions participating in the SEOR-Mama group (GEORM). In total, the standards of practice in 969 patients with breast cancer after surgery were evaluated. Results The response rate was 70% (28/40 centers). In 98.5% of cases 3D conformal treatment was used. All the institutions employed CT-based planning treatment. Boost was performed in 56.4% of patients: electrons in 59.8%, photons in 23.7% and HDR brachytherapy in 8.8%. Fractionation was standard in 93.1% of patients. Supine position was the most frequent. Only 3 centers used prone position. The common organs of risk delimited were: homolateral lung (80.8%) and heart (80.8%). In 84% histograms were used. An 80.8% of the centers used isocentric technique. In 62.5% asymmetric fields were employed. CTV was delimited in 46.2%, PTV in 65% and both in 38.5%. A 65% of the centers checked with portal films. IMRT and hypofractionation were used in 1% and in 5.5% respectively. Conclusion In most of centers, 3D conformal treatment and CT-based planning treatment were used. IMRT and hypofractionation are currently poorly implemented in Spain. PMID:24377012

  18. Application of data assimilation technique for flow field simulation for Kaiga site using TAPM model

    International Nuclear Information System (INIS)

    Shrivastava, R.; Oza, R.B.; Puranik, V.D.; Hegde, M.N.; Kushwaha, H.S.

    2008-01-01

    The data assimilation techniques are becoming popular nowadays to get realistic flow field simulation for the site under consideration. The present paper describes data assimilation technique for flow field simulation for Kaiga site using the air pollution model (TAPM) developed by CSIRO, Australia. In this, the TAPM model was run for Kaiga site for a period of one month (Nov. 2004) using the analysed meteorological data supplied with the model for Central Asian (CAS) region and the model solutions were nudged with the observed wind speed and wind direction data available for the site. The model was run with 4 nested grids with grid spacing varying from 30km, 10km, 3km and 1km respectively. The models generated results with and without nudging are statistically compared with the observations. (author)

  19. Metabolic syndrome after bariatric surgery. Results depending on the technique performed.

    Science.gov (United States)

    Gracia-Solanas, Jose Antonio; Elia, M; Aguilella, V; Ramirez, J M; Martínez, J; Bielsa, M A; Martínez, M

    2011-02-01

    There is a lack of long-term studies for metabolic syndrome after bariatric surgery. Our aim is to show the evolution of the parameters that define the metabolic syndrome after bariatric surgery, up to 10 years of follow-up, in order to clarify what technique gets better results with fewer complications. The IDF definition of the metabolic syndrome was used for this study. One hundred twenty-five morbid obese and superobese patients underwent vertical banded gastroplasty. Two hundred sixty-five morbid obese and superobese patients had biliopancreatic diversion (Scopinaro and modified biliopancreatic diversions), and 152 morbid obese patients underwent laparoscopic gastric bypass. A mean follow-up of up to 7 years was done in all groups. Prior to surgery, metabolic syndrome was diagnosed in 114 patients of Scopinaro group (76%), in 85 patients of modified biliopancreatic diversion group (73.9%), in 81 patients of laparoscopic gastric bypass (53.4%), and in 98 patients of vertical banded gastroplasty (78.4%). When metabolic syndrome parameters were evaluated at 7 years of follow-up, owing to weight gain, these results changed nearby to preoperative values in both laparoscopic gastric bypass and vertical banded gastroplasty groups. According to our results, the best technique to resolve metabolic syndrome is the modified biliopancreatic diversion. Due to its high morbidity, it only must be considered in superobese patients. In obese patients, the laparoscopic gastric bypass may be a less agressive choice, but it should be coupled with lifestyle changes to keep away from the weight gain in the long run. Restrictive procedures may be indicated only in a few well-selected cases.

  20. Results of Patello-Tibial Cerclage Wire Technique for Comminuted Patella Fractures Treated with Partial Patellectomy

    Directory of Open Access Journals (Sweden)

    Ender Alagöz

    2014-12-01

    Full Text Available Aim: Partial patellectomy and patellotibial cerclage technique used in comminuted inferior pole patellar fractures were evaluated and the results were discussed. Methods: Thirteen patients who have undergone partial distal patellar excision were evaluated in the study. In all patients, the inferior pole of the patella was resected, patellar tendon was sutured to the proximal patellar fragment and patellotibial cerclage was performed. At the last visit, the patients were evaluated using measurement of the distance between the superior pole of the patella and the tibial tubercle, the Lysholm knee scoring scale, knee range of motion and thigh circumference measurement. Results: The mean flexion value was 131.10 (±4.6 in normal knees and 117.20 (±8.0 in operated knees. The mean thigh diameter was 49.5 (±3.7 cm and 46.4 (±4.5 cm in normal knees and in operated knees, respectively. The mean Lysholm knee score in the patient group was 84.3 (±17.1 points. The mean distance between the superior pole of the patella and the tibial tubercle was 10.6 (±1.0 cm in normal knees and 10.1 (±1.2 cm in operated knees. The exstensor mechanism was intact in all patients and no revision surgery was performed. Conclusion: Patellotibial cerclage technique performed after partial patellectomy permits early motion and protects patients from harmful effects of immobilization; and good functional results are obtained if patients start early knee motion.

  1. Different Techniques For Producing Precision Holes (>20 mm) In Hardened Steel—Comparative Results

    Science.gov (United States)

    Coelho, R. T.; Tanikawa, S. T.

    2009-11-01

    High speed machining (HSM), or high performance machining, has been one of the most recent technological advances. When applied to milling operations, using adequate machines, CAM programs and tooling, it allows cutting hardened steels, which was not feasible just a couple of years ago. The use of very stiff and precision machines has created the possibilities of machining holes in hardened steels, such as AISI H13 with 48-50 HRC, using helical interpolations, for example. Such process is particularly useful for holes with diameter bigger than normal solid carbide drills commercially available, around 20 mm, or higher. Such holes may need narrow tolerances, fine surface finishing, which can be obtained just by end milling operations. The present work compares some of the strategies used to obtain such holes by end milling, and also some techniques employed to finish them, by milling, boring and also by fine grinding at the same machine. Results indicate that it is possible to obtain holes with less than 0.36 m in circularity, 7.41 m in cylindricity and 0.12 m in surface roughness Ra. Additionally, there is less possibilities of obtaining heat affected layers when using such technique.

  2. Total aortic arch replacement with the elephant trunk technique: single-centre 30-year results.

    Science.gov (United States)

    Shrestha, Malakh; Martens, Andreas; Krüger, Heike; Maeding, Illona; Ius, Fabio; Fleissner, Felix; Haverich, Axel

    2014-02-01

    treatment of combined diseases of the aortic arch and descending aorta. The initial learning curve, acute dissections, re-do and concomitant procedures partially explain the higher mortality rate. Despite the development of new hybrid techniques, there is still a role for the classical ET in selected patients, particularly in the context of proven long-term results and cost effectiveness.

  3. A neuro-fuzzy computing technique for modeling hydrological time series

    Science.gov (United States)

    Nayak, P. C.; Sudheer, K. P.; Rangan, D. M.; Ramasastri, K. S.

    2004-05-01

    Intelligent computing tools such as artificial neural network (ANN) and fuzzy logic approaches are proven to be efficient when applied individually to a variety of problems. Recently there has been a growing interest in combining both these approaches, and as a result, neuro-fuzzy computing techniques have evolved. This approach has been tested and evaluated in the field of signal processing and related areas, but researchers have only begun evaluating the potential of this neuro-fuzzy hybrid approach in hydrologic modeling studies. This paper presents the application of an adaptive neuro fuzzy inference system (ANFIS) to hydrologic time series modeling, and is illustrated by an application to model the river flow of Baitarani River in Orissa state, India. An introduction to the ANFIS modeling approach is also presented. The advantage of the method is that it does not require the model structure to be known a priori, in contrast to most of the time series modeling techniques. The results showed that the ANFIS forecasted flow series preserves the statistical properties of the original flow series. The model showed good performance in terms of various statistical indices. The results are highly promising, and a comparative analysis suggests that the proposed modeling approach outperforms ANNs and other traditional time series models in terms of computational speed, forecast errors, efficiency, peak flow estimation etc. It was observed that the ANFIS model preserves the potential of the ANN approach fully, and eases the model building process.

  4. Demand Management Based on Model Predictive Control Techniques

    Directory of Open Access Journals (Sweden)

    Yasser A. Davizón

    2014-01-01

    Full Text Available Demand management (DM is the process that helps companies to sell the right product to the right customer, at the right time, and for the right price. Therefore the challenge for any company is to determine how much to sell, at what price, and to which market segment while maximizing its profits. DM also helps managers efficiently allocate undifferentiated units of capacity to the available demand with the goal of maximizing revenue. This paper introduces control system approach to demand management with dynamic pricing (DP using the model predictive control (MPC technique. In addition, we present a proper dynamical system analogy based on active suspension and a stability analysis is provided via the Lyapunov direct method.

  5. Percutaneous transluminal angioplasty in the region of the renal artery: indications, technique and results

    Energy Technology Data Exchange (ETDEWEB)

    Olbert, F; Ogris, E; Muzika, N; Schlegl, A; Vacariu, O; Diez, W

    1985-01-01

    The paper reports the results obtained by percutaneous transluminal angioplasty (PTA) in the treatment of renal artery stenosis in 25 patients with secondary hypertension and discusses indications and the technique used. The follow-up period ranged from 0.5 to 12 months. All interventions were performed with the Olbert catheter system. Following PTA a significant decrease in systolic, diastolic and mean arterial pressure was observed in nearly all patients. The response of the plasma renin activity (PRA) to orthostatic stimulation and pharmacological stimulation by furosemide was determined in a subset of 15 patients before and after PTA. A significant decrease in both basal and stimulated PRA values was observed subsequent to PTA. The decrease in PRA values after successful PTA did not, however, correlate with the extent of the blood pressure changes. (Author).

  6. Percutaneous transluminal angioplasty in the region of the renal artery: indications, technique and results

    International Nuclear Information System (INIS)

    Olbert, F.; Ogris, E.; Muzika, N.; Schlegl, A.; Vacariu, O.; Diez, W.

    1985-01-01

    The paper reports the results obtained by percutaneous transluminal angioplasty (PTA) in the treatment of renal artery stenosis in 25 patients with secondary hypertension and discusses indications and the technique used. The follow-up period ranged from 0.5 to 12 months. All interventions were performed with the Olbert catheter system. Following PTA a significant decrease in systolic, diastolic and mean arterial pressure was observed in nearly all patients. The response of the plasma renin activity (PRA) to orthostatic stimulation and pharmacological stimulation by furosemide was determined in a subset of 15 patients before and after PTA. A significant decrease in both basal and stimulated PRA values was observed subsequent to PTA. The decrease in PRA values after successful PTA did not, however, correlate with the extent of the blood pressure changes. (Author)

  7. Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

    International Nuclear Information System (INIS)

    Becker, Hans-Christoph; Johnson, Thorsten

    2012-01-01

    Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

  8. Technique and results of the spinal computed tomography in the diagnosis of cervical disc disease

    International Nuclear Information System (INIS)

    Artmann, H.; Salbeck, R.; Grau, H.

    1985-01-01

    We give a description of a technique of the patient's positioning with traction of the arms during the cervical spinal computed tomography which allows to draw the shoulders downwards by about one to three cervical segments. By this method the quality of the images can be improved in 96% in the cervical segment 6/7 and in 81% in the cervical/thoracal segment 7/1 to such a degree that a reliable judgement of the soft parts in the spinal canal becomes possible. The diagnostic reliability of the computed tomography of the cervical disc herniation is thus improved so that the necessity of a myelography is decreasing. The results of 396 cervical spinal computed tomographies are presented. (orig.) [de

  9. Experimental investigation of the predictive capabilities of data driven modeling techniques in hydrology - Part 2: Application

    Directory of Open Access Journals (Sweden)

    A. Elshorbagy

    2010-10-01

    Full Text Available In this second part of the two-part paper, the data driven modeling (DDM experiment, presented and explained in the first part, is implemented. Inputs for the five case studies (half-hourly actual evapotranspiration, daily peat soil moisture, daily till soil moisture, and two daily rainfall-runoff datasets are identified, either based on previous studies or using the mutual information content. Twelve groups (realizations were randomly generated from each dataset by randomly sampling without replacement from the original dataset. Neural networks (ANNs, genetic programming (GP, evolutionary polynomial regression (EPR, Support vector machines (SVM, M5 model trees (M5, K-nearest neighbors (K-nn, and multiple linear regression (MLR techniques are implemented and applied to each of the 12 realizations of each case study. The predictive accuracy and uncertainties of the various techniques are assessed using multiple average overall error measures, scatter plots, frequency distribution of model residuals, and the deterioration rate of prediction performance during the testing phase. Gamma test is used as a guide to assist in selecting the appropriate modeling technique. Unlike two nonlinear soil moisture case studies, the results of the experiment conducted in this research study show that ANNs were a sub-optimal choice for the actual evapotranspiration and the two rainfall-runoff case studies. GP is the most successful technique due to its ability to adapt the model complexity to the modeled data. EPR performance could be close to GP with datasets that are more linear than nonlinear. SVM is sensitive to the kernel choice and if appropriately selected, the performance of SVM can improve. M5 performs very well with linear and semi linear data, which cover wide range of hydrological situations. In highly nonlinear case studies, ANNs, K-nn, and GP could be more successful than other modeling techniques. K-nn is also successful in linear situations, and it

  10. Experimental investigation of the predictive capabilities of data driven modeling techniques in hydrology - Part 2: Application

    Science.gov (United States)

    Elshorbagy, A.; Corzo, G.; Srinivasulu, S.; Solomatine, D. P.

    2010-10-01

    In this second part of the two-part paper, the data driven modeling (DDM) experiment, presented and explained in the first part, is implemented. Inputs for the five case studies (half-hourly actual evapotranspiration, daily peat soil moisture, daily till soil moisture, and two daily rainfall-runoff datasets) are identified, either based on previous studies or using the mutual information content. Twelve groups (realizations) were randomly generated from each dataset by randomly sampling without replacement from the original dataset. Neural networks (ANNs), genetic programming (GP), evolutionary polynomial regression (EPR), Support vector machines (SVM), M5 model trees (M5), K-nearest neighbors (K-nn), and multiple linear regression (MLR) techniques are implemented and applied to each of the 12 realizations of each case study. The predictive accuracy and uncertainties of the various techniques are assessed using multiple average overall error measures, scatter plots, frequency distribution of model residuals, and the deterioration rate of prediction performance during the testing phase. Gamma test is used as a guide to assist in selecting the appropriate modeling technique. Unlike two nonlinear soil moisture case studies, the results of the experiment conducted in this research study show that ANNs were a sub-optimal choice for the actual evapotranspiration and the two rainfall-runoff case studies. GP is the most successful technique due to its ability to adapt the model complexity to the modeled data. EPR performance could be close to GP with datasets that are more linear than nonlinear. SVM is sensitive to the kernel choice and if appropriately selected, the performance of SVM can improve. M5 performs very well with linear and semi linear data, which cover wide range of hydrological situations. In highly nonlinear case studies, ANNs, K-nn, and GP could be more successful than other modeling techniques. K-nn is also successful in linear situations, and it should

  11. Use of machine learning techniques for modeling of snow depth

    Directory of Open Access Journals (Sweden)

    G. V. Ayzel

    2017-01-01

    Full Text Available Snow exerts significant regulating effect on the land hydrological cycle since it controls intensity of heat and water exchange between the soil-vegetative cover and the atmosphere. Estimating of a spring flood runoff or a rain-flood on mountainous rivers requires understanding of the snow cover dynamics on a watershed. In our work, solving a problem of the snow cover depth modeling is based on both available databases of hydro-meteorological observations and easily accessible scientific software that allows complete reproduction of investigation results and further development of this theme by scientific community. In this research we used the daily observational data on the snow cover and surface meteorological parameters, obtained at three stations situated in different geographical regions: Col de Porte (France, Sodankyla (Finland, and Snoquamie Pass (USA.Statistical modeling of the snow cover depth is based on a complex of freely distributed the present-day machine learning models: Decision Trees, Adaptive Boosting, Gradient Boosting. It is demonstrated that use of combination of modern machine learning methods with available meteorological data provides the good accuracy of the snow cover modeling. The best results of snow cover depth modeling for every investigated site were obtained by the ensemble method of gradient boosting above decision trees – this model reproduces well both, the periods of snow cover accumulation and its melting. The purposeful character of learning process for models of the gradient boosting type, their ensemble character, and use of combined redundancy of a test sample in learning procedure makes this type of models a good and sustainable research tool. The results obtained can be used for estimating the snow cover characteristics for river basins where hydro-meteorological information is absent or insufficient.

  12. Extending the reach of strong-coupling: an iterative technique for Hamiltonian lattice models

    International Nuclear Information System (INIS)

    Alberty, J.; Greensite, J.; Patkos, A.

    1983-12-01

    The authors propose an iterative method for doing lattice strong-coupling-like calculations in a range of medium to weak couplings. The method is a modified Lanczos scheme, with greatly improved convergence properties. The technique is tested on the Mathieu equation and on a Hamiltonian finite-chain XY model, with excellent results. (Auth.)

  13. The commercial use of segmentation and predictive modeling techniques for database marketing in the Netherlands

    NARCIS (Netherlands)

    Verhoef, PC; Spring, PN; Hoekstra, JC; Leeflang, PSH

    Although the application of segmentation and predictive modeling is an important topic in the database marketing (DBM) literature, no study has yet investigated the extent of adoption of these techniques. We present the results of a Dutch survey involving 228 database marketing companies. We find

  14. Tapering of the CHESS-APS undulator: Results and modelling

    International Nuclear Information System (INIS)

    Lai, B.; Viccaro, P.J.; Dejus, R.; Gluskin, E.; Yun, W.B.; McNulty, I.; Henderson, C.; White, J.; Shen, Q.; Finkelstein, K.

    1992-01-01

    When the magnetic gap of an undulator is tapered along the beam direction, the slowly varying peak field B o introduces a spread in the value of the deflection parameter K. The result is a broad energy-band undulator that still maintains high degree of spatial collimation. These properties are very useful for EXAFS and energy dispersive techniques. We have characterized the CHESS-APS undulator (1 υ = 3.3cm) at one tapered configuration (10% change of the magnetic gap from one end of the undulator to the other). Spatial distribution and energy spectra of the first three harmonics through a pinhole were measured. The on-axis first harmonic width increased from 0.27 keV to 0.61 keV (FWHM) at the central energy of E 1 = 6.6 keV (K average = 0.69). Broadening in the angular distribution due to tapering was minimal. These results will be compared with computer modelling which simulates the actual electron trajectory in the tapered case

  15. Indications, techniques and results of postoperative brachytherapy in cancer of the oral cavity

    International Nuclear Information System (INIS)

    Pernot, M.; Aletti, P.; Carolus, J.M.; Marquis, I.; Hoffstetter, S.; Maaloul, F.; Peiffert, D.; Lapeyre, M.; Luporsi, E.; Marchal, C.; Noeel, A.; Bey, P.

    1995-01-01

    Purpose/objective: We tried to reduce the number of local recurrences after surgery and external beam irradiation (EBI) in carcinoma of the oral cavity, when margins were positive or close. Material and methods: From 1980 to 1992, we treated 97 cases of carcinomas of the oral cavity by postoperative brachytherapy. Surgery was combined with EBI+brachytherapy in 51 cases and with brachytherapy alone in 46 cases. We treated 29 T1, 34 T2, 30 T3T4 and four Tx (73% were N0 at first examination and 23% had positive nodes). The type of surgery is analysed. Brachytherapy was performed in one or two planes along the surgical scar. If the mandibular rim was resected, especially when the tongue or the remaining floor were sutured to the internal face of the inferior lip or to the buccal mucosa, the bridge technique was used. To decrease the dose to the inferior part of the mandible, the bridge was modified thanks to experimental dosimetry. Results: At 5 years, the local control (LC) is 89%, the locoregional control (LRC) 82%, the specific survival (SS) 74% and the overall survival (OS) 67%. Complications: We noted 19% of grade 1 (minor), 12% of grade 2 (moderate) and 6% of grade 3 (major) complications. Conclusion: Compared with the results of the literature, we think that postoperative brachytherapy can improve classical radiosurgical results in selected cases with a risk of local recurrence

  16. Modeling of high-pressure generation using the laser colliding foil technique

    Energy Technology Data Exchange (ETDEWEB)

    Fabbro, R.; Faral, B.; Virmont, J.; Cottet, F.; Romain, J.P.

    1989-03-01

    An analytical model describing the collision of two foils is presented and applied to the collision of laser-accelerated foils. Numerical simulations have been made to verify this model and to compare its results in the case of laser-accelerated foils. Scaling laws relating the different parameters (shock pressure, laser intensity, target material, etc.) have been established. The application of this technique to high-pressure equation of state experiments is then discussed.

  17. Modeling of high-pressure generation using the laser colliding foil technique

    International Nuclear Information System (INIS)

    Fabbro, R.; Faral, B.; Virmont, J.; Cottet, F.; Romain, J.P.

    1989-01-01

    An analytical model describing the collision of two foils is presented and applied to the collision of laser-accelerated foils. Numerical simulations have been made to verify this model and to compare its results in the case of laser-accelerated foils. Scaling laws relating the different parameters (shock pressure, laser intensity, target material, etc.) have been established. The application of this technique to high-pressure equation of state experiments is then discussed

  18. Antegrade scrotal sclerotherapy of internal spermatic veins for varicocele treatment: technique, complications, and results

    Directory of Open Access Journals (Sweden)

    Alessandro Crestani

    2016-01-01

    Full Text Available Varicocele repair is mainly indicated in young adult patients with clinical palpable varicocele and abnormal semen parameters. Varicocele treatment is associated with a significant improvement in sperm concentration, motility, morphology, and pregnancy rate. Antegrade scrotal sclerotherapy (ASS represented one of the main alternatives to the traditional inguinal or suprainguinal surgical ligation. This article reviews the use of ASS for varicocele treatment. We provide a brief overview of the history of the procedure and present our methods used in ASS. In addition, we review complication and success of ASS, including our own retrospective data of treating 674 patients over the last 17 years. Herein, we analyzed step by step the ASS technique and described our results with an original modified technique with a long follow-up. Between December 1997 and December 2014, we performed 674 ASS. Mean operative time was 14 min (range 9 to 50 min. No significant intraoperative complications were reported. Within 90 days from the procedure, postoperative complications were recorded in overall 49 (7.2% patients. No major complications were recorded. A persistent/recurrent varicocele was detected in 40 (5.9% cases. In 32/40 (80% cases, patients showed preoperative grade III varicoceles. In patients with a low sperm number before surgery, sperm count improved from 13 × 10 6 to 21 × 10 6 ml−1 (P < 0.001. The median value of the percentage of progressive motile forms at 1 h improved from 25% to 45% (P < 0.001. Percentage of normal forms increased from 17% before surgery to 35% 1 year after the procedure (P < 0.001. In the subgroup of the 168 infertile patients, 52 (31% fathered offspring at a 12-month-minimum follow-up. Therefore, ASS is an effective minimal invasive treatment for varicocele with low recurrence/persistence rate.

  19. GRAVTool, a Package to Compute Geoid Model by Remove-Compute-Restore Technique

    Science.gov (United States)

    Marotta, G. S.; Blitzkow, D.; Vidotti, R. M.

    2015-12-01

    Currently, there are several methods to determine geoid models. They can be based on terrestrial gravity data, geopotential coefficients, astro-geodetic data or a combination of them. Among the techniques to compute a precise geoid model, the Remove-Compute-Restore (RCR) has been widely applied. It considers short, medium and long wavelengths derived from altitude data provided by Digital Terrain Models (DTM), terrestrial gravity data and global geopotential coefficients, respectively. In order to apply this technique, it is necessary to create procedures that compute gravity anomalies and geoid models, by the integration of different wavelengths, and that adjust these models to one local vertical datum. This research presents a developed package called GRAVTool based on MATLAB software to compute local geoid models by RCR technique and its application in a study area. The studied area comprehends the federal district of Brazil, with ~6000 km², wavy relief, heights varying from 600 m to 1340 m, located between the coordinates 48.25ºW, 15.45ºS and 47.33ºW, 16.06ºS. The results of the numerical example on the studied area show the local geoid model computed by the GRAVTool package (Figure), using 1377 terrestrial gravity data, SRTM data with 3 arc second of resolution, and geopotential coefficients of the EIGEN-6C4 model to degree 360. The accuracy of the computed model (σ = ± 0.071 m, RMS = 0.069 m, maximum = 0.178 m and minimum = -0.123 m) matches the uncertainty (σ =± 0.073) of 21 points randomly spaced where the geoid was computed by geometrical leveling technique supported by positioning GNSS. The results were also better than those achieved by Brazilian official regional geoid model (σ = ± 0.099 m, RMS = 0.208 m, maximum = 0.419 m and minimum = -0.040 m).

  20. Photolysis frequency measurement techniques: results of a comparison within the ACCENT project

    Directory of Open Access Journals (Sweden)

    K. C. Clemitshaw

    2008-09-01

    Full Text Available An intercomparison of different radiometric techniques measuring atmospheric photolysis frequencies j(NO2, j(HCHO and j(O1D was carried out in a two-week field campaign in June 2005 at Jülich, Germany. Three double-monochromator based spectroradiometers (DM-SR, three single-monochromator based spectroradiometers with diode-array detectors (SM-SR and seventeen filter radiometers (FR (ten j(NO2-FR, seven j(O1D-FR took part in this comparison. For j(NO2, all spectroradiometer results agreed within ±3%. For j(HCHO, agreement was slightly poorer between −8% and +4% of the DM-SR reference result. For the SM-SR deviations were explained by poorer spectral resolutions and lower accuracies caused by decreased sensitivities of the photodiode arrays in a wavelength range below 350 nm. For j(O1D, the results were more complex within +8% and −4% with increasing deviations towards larger solar zenith angles for the SM-SR. The direction and the magnitude of the deviations were dependent on the technique of background determination. All j(NO2-FR showed good linearity with single calibration factors being sufficient to convert from output voltages to j(NO2. Measurements were feasible until sunset and comparison with previous calibrations showed good long-term stability. For the j(O1D-FR, conversion from output voltages to j(O1D needed calibration factors and correction functions considering the influences of total ozone column and elevation of the sun. All instruments showed good linearity at photolysis frequencies exceeding about 10% of maximum values. At larger solar zenith angles, the agreement was non-uniform with deviations explainable by insufficient correction functions. Comparison with previous calibrations for some j(O1D-FR indicated

  1. An experimental technique for the modelling of air flow movements in nuclear plant

    International Nuclear Information System (INIS)

    Ainsworth, R.W.; Hallas, N.J.

    1986-01-01

    This paper describes an experimental technique developed at Harwell to model ventilation flows in plant at 1/5th scale. The technique achieves dynamic similarity not only for forced convection imposed by the plant ventilation system, but also for the interaction between natural convection (from heated objects) and forced convection. The use of a scale model to study flow of fluids is a well established technique, relying upon various criteria, expressed in terms of dimensionless numbers, to achieve dynamic similarity. For forced convective flows, simulation of Reynolds number is sufficient, but to model natural convection and its interaction with forced convection, the Rayleigh, Grashof and Prandtl numbers must be simulated at the same time. This paper describes such a technique, used in experiments on a hypothetical glove box cell to study the interaction between forced and natural convection. The model contained features typically present in a cell, such as a man, motor, stairs, glove box, etc. The aim of the experiment was to study the overall flow patterns, especially around the model man 'working' at the glove box. The cell ventilation was theoretically designed to produce a downward flow over the face of the man working at the glove box. However, the results have shown that the flow velocities produced an upwards flow over the face of the man. The work has indicated the viability of modelling simultaneously the forced and natural convection processes in a cell. It has also demonstrated that simplistic assumptions cannot be made about ventilation flow patterns. (author)

  2. First characterization of the expiratory flow increase technique: method development and results analysis

    International Nuclear Information System (INIS)

    Maréchal, L; Barthod, C; Jeulin, J C

    2009-01-01

    This study provides an important contribution to the definition of the expiratory flow increase technique (EFIT). So far, no measuring means were suited to assess the manual EFIT performed on infants. The proposed method aims at objectively defining the EFIT based on the quantification of pertinent cognitive parameters used by physiotherapists when practicing. We designed and realized customized instrumented gloves endowed with pressure and displacement sensors, and the associated electronics and software. This new system is specific to the manoeuvre, to the user and innocuous for the patient. Data were collected and analysed on infants with bronchiolitis managed by an expert physiotherapist. The analysis presented is realized on a group of seven subjects (mean age: 6.1 months, SD: 1.1; mean chest circumference: 44.8 cm, SD: 1.9). The results are consistent with the physiotherapist's tactility. In spite of inevitable variability due to measurements on infants, repeatable quantitative data could be reported regarding the manoeuvre characteristics: the magnitudes of displacements do not exceed 10 mm on both hands; the movement of the thoracic hand is more vertical than the movement of the abdominal hand; the maximum applied pressure with the thoracic hand is about twice higher than with the abdominal hand; the thrust of the manual compression lasts (590 ± 62) ms. Inter-operators measurements are in progress in order to generalize these results

  3. Clinical results of a concomitant boost radiotherapy technique for muscle-invasive bladder cancer

    Energy Technology Data Exchange (ETDEWEB)

    Piet, A H.M.; Hulshof, M C.C.M.; Pieters, B R; Koning, C C.E. [Dept. of Radiation Oncology, Academic Medical Center, Univ. of Amsterdam (Netherlands); Pos, F J [Dept. of Radiation Oncology, The Netherlands Cancer Inst., Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Reijke, T.M. de [Dept. of Urology, Academic Medical Center, Univ. of Amsterdam (Netherlands)

    2008-06-15

    Purpose: to update the results of external radiotherapy with a focal concomitant boost technique on local control and bladder function in patients with muscle-invasive bladder cancer. Patients and methods: the authors retrospectively evaluated 92 elderly or disabled patients with localized T2-4 N0-1 M0 transitional cell carcinoma of the bladder and a median age of 79 years, not suitable for radical surgery and treated between 1994 and 2005. Treatment consisted of a dose of 40 Gy/2 Gy to the small pelvis with a daily concomitant boost of 0.75 Gy to the tumor. Total dose was 55 Gy in 4 weeks. Results: complete remission rate after evaluation by means of cystoscopy at 3 months was 78%. 3-year local control rate amounted to 56%, and 3-year overall survival to 36%. The posttreatment bladder capacity was comparable with the pretreatment capacity and was {>=} 200 ml in 81% of the cases. Mean bladder capacity did not deteriorate at longer follow-up. Conclusion: the local control rate after external beam radiotherapy in elderly patients with a focal concomitant boost for localized muscle-invasive bladder cancer was 56% at 3 years. Functional bladder outcome was good. (orig.)

  4. Clinical results of a concomitant boost radiotherapy technique for muscle-invasive bladder cancer

    International Nuclear Information System (INIS)

    Piet, A.H.M.; Hulshof, M.C.C.M.; Pieters, B.R.; Koning, C.C.E.; Pos, F.J.; Reijke, T.M. de

    2008-01-01

    Purpose: to update the results of external radiotherapy with a focal concomitant boost technique on local control and bladder function in patients with muscle-invasive bladder cancer. Patients and methods: the authors retrospectively evaluated 92 elderly or disabled patients with localized T2-4 N0-1 M0 transitional cell carcinoma of the bladder and a median age of 79 years, not suitable for radical surgery and treated between 1994 and 2005. Treatment consisted of a dose of 40 Gy/2 Gy to the small pelvis with a daily concomitant boost of 0.75 Gy to the tumor. Total dose was 55 Gy in 4 weeks. Results: complete remission rate after evaluation by means of cystoscopy at 3 months was 78%. 3-year local control rate amounted to 56%, and 3-year overall survival to 36%. The posttreatment bladder capacity was comparable with the pretreatment capacity and was ≥ 200 ml in 81% of the cases. Mean bladder capacity did not deteriorate at longer follow-up. Conclusion: the local control rate after external beam radiotherapy in elderly patients with a focal concomitant boost for localized muscle-invasive bladder cancer was 56% at 3 years. Functional bladder outcome was good. (orig.)

  5. Results of a minimally invasive technique for treatment of unicameral bone cysts.

    Science.gov (United States)

    Mik, Gökçe; Arkader, Alexandre; Manteghi, Alexander; Dormans, John P

    2009-11-01

    Unicameral bone cysts are benign bone lesions commonly seen in pediatric patients. Several treatment methods have been described with variable results and high recurrence rates. We previously reported short-term success of a minimally invasive technique that includes combining percutaneous decompression and grafting with medical-grade calcium sulfate pellets. The purpose of this study was to review the additional long-term results with a minimum followup of 24 months (average, 37 months; range, 24-70 months). We identified 55 patients with an average age of 10.8 years (range, 1.3-18 years). Forty-one of 55 lesions occurred in the humerus and femur. Forty-four of 55 (80%) patients had a partial or complete response after initial surgery; of these, seven obtained a partial or complete response after a repeat surgery (cumulative healing rate, 94%). Two patients underwent a third surgery (cumulative healing rate, 98%). One underwent a third repeat surgery (cumulative healing rate, 100%). There were no major complications associated with the procedure. Two patients had a superficial infection that resolved with oral antibiotics. Although some patients required a repeat procedure, complete or partial response at a minimum 24 months' followup was achieved in all patients. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

  6. A Morphing Technique Applied to Lung Motions in Radiotherapy: Preliminary Results

    Directory of Open Access Journals (Sweden)

    R. Laurent

    2010-01-01

    Full Text Available Organ motion leads to dosimetric uncertainties during a patient’s treatment. Much work has been done to quantify the dosimetric effects of lung movement during radiation treatment. There is a particular need for a good description and prediction of organ motion. To describe lung motion more precisely, we have examined the possibility of using a computer technique: a morphing algorithm. Morphing is an iterative method which consists of blending one image into another image. To evaluate the use of morphing, Four Dimensions Computed Tomography (4DCT acquisition of a patient was performed. The lungs were automatically segmented for different phases, and morphing was performed using the end-inspiration and the end-expiration phase scans only. Intermediate morphing files were compared with 4DCT intermediate images. The results showed good agreement between morphing images and 4DCT images: fewer than 2 % of the 512 by 256 voxels were wrongly classified as belonging/not belonging to a lung section. This paper presents preliminary results, and our morphing algorithm needs improvement. We can infer that morphing offers considerable advantages in terms of radiation protection of the patient during the diagnosis phase, handling of artifacts, definition of organ contours and description of organ motion.

  7. Evaluation of in-vehicle HMI using occlusion techniques: experimental results and practical implications.

    Science.gov (United States)

    Baumann, Martin; Keinath, Andreas; Krems, Josef F; Bengler, Klaus

    2004-05-01

    Despite the usefulness of new on-board information systems one has to be concerned about the potential distraction effects that they impose on the driver. Therefore, methods and procedures are necessary to assess the visual demand that is connected to the usage of an on-board system. The occlusion-method is considered a strong candidate as a procedure for evaluating display designs with regard to their visual demand. This paper reports results from two experimental studies conducted to further evaluate this method. In the first study, performance in using an in-car navigation system was measured under three conditions: static (parking lot), occlusion (shutter glasses), and driving. The results show that the occlusion-procedure can be used to simulate visual requirements of real traffic conditions. In a second study the occlusion method was compared to a global evaluation criterion based on the total task time. It can be demonstrated that the occlusion method can identify tasks which meet this criterion, but are yet irresolvable under driving conditions. It is concluded that the occlusion technique seems to be a reliable and valid method for evaluating visual and dialogue aspects of in-car information systems.

  8. High dose rate brachytherapy (HDRB) in prostate cancer - technique description and preliminary results

    International Nuclear Information System (INIS)

    Cordova Junior, Ardo Lotar; Salvajoli, Joao Victor; Pelizzon, Antonio CAssio Assis; Cecilio, Paulo Jose

    1998-01-01

    Describe the technique and preliminary results of high dose rate brachytherapy (HDRB) in localized prostate cancer. Subjects methods: Between March, 1997 and April, 1998, 26 patients were treated with external beam radiotherapy (45 to 50.4 Gy - 1.8 Gy per day) and implants (16 Gy in 2 days - twice a day). Median age was 68 years. The distribution by clinical stage was: 5 T1c, 9 T2a, 10 T2b and 2 T3a. Median initial PSA was 16 ng/ml. Results: With a median follow-up of 4 months, 85% of patients showed normal levels of PSA, with a median of 0.6 ng/ml, 60 to 90 days after treatment. Dysuria grades 1 and 2 and proctitis grade 1 were found in 11,3 and 5 patients, respectively. Conclusion: The method is safe, with acceptable early side effects. Longer follow-up is necessary before drawing any conclusions. (author)

  9. Accuracy Enhanced Stability and Structure Preserving Model Reduction Technique for Dynamical Systems with Second Order Structure

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat; Shaker, Hamid Reza

    A method for model reduction of dynamical systems with the second order structure is proposed in this paper. The proposed technique preserves the second order structure of the system, and also preserves the stability of the original systems. The method uses the controllability and observability...... gramians within the time interval to build the appropriate Petrov-Galerkin projection for dynamical systems within the time interval of interest. The bound on approximation error is also derived. The numerical results are compared with the counterparts from other techniques. The results confirm...

  10. Computational modelling of the HyperVapotron cooling technique

    Energy Technology Data Exchange (ETDEWEB)

    Milnes, Joseph, E-mail: Joe.Milnes@ccfe.ac.uk [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Burns, Alan [School of Process Material and Environmental Engineering, CFD Centre, University of Leeds, Leeds, LS2 9JT (United Kingdom); ANSYS UK, Milton Park, Oxfordshire (United Kingdom); Drikakis, Dimitris [Department of Engineering Physics, Cranfield University, Cranfield, MK43 0AL (United Kingdom)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer The heat transfer mechanisms within a HyperVapotron are examined. Black-Right-Pointing-Pointer A multiphase, CFD model is developed. Black-Right-Pointing-Pointer Modelling choices for turbulence and wall boiling are evaluated. Black-Right-Pointing-Pointer Considerable improvements in accuracy are found compared to standard boiling models. Black-Right-Pointing-Pointer The model should enable significant virtual prototyping to be performed. - Abstract: Efficient heat transfer technologies are essential for magnetically confined fusion reactors; this applies to both the current generation of experimental reactors as well as future power plants. A number of High Heat Flux devices have therefore been developed specifically for this application. One of the most promising candidates is the HyperVapotron, a water cooled device which relies on internal fins and boiling heat transfer to maximise the heat transfer capability. Over the past 30 years, numerous variations of the HyperVapotron have been built and tested at fusion research centres around the globe resulting in devices that can now sustain heat fluxes in the region of 20-30 MW/m{sup 2} in steady state. Until recently, there had been few attempts to model or understand the internal heat transfer mechanisms responsible for this exceptional performance with the result that design improvements have been traditionally sought experimentally which is both inefficient and costly. This paper presents the successful attempt to develop an engineering model of the HyperVapotron device using customisation of commercial Computational Fluid Dynamics software. To establish the most appropriate modelling choices, in-depth studies were performed examining the turbulence models (within the Reynolds Averaged Navier Stokes framework), near wall methods, grid resolution and boiling submodels. Comparing the CFD solutions with HyperVapotron experimental data suggests that a RANS-based, multiphase

  11. Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.

    Science.gov (United States)

    Yu, Zhe; Sun, Honghui; Fan, Qingyu; Long, Hua; Yang, Tongtao; Ma, Bao'an

    2009-05-01

    In experimental musculoskeletal oncology, there remains a need for animal models that can be used to assess the efficacy of new and innovative treatment methodologies for bone tumors. Rat plays a very important role in the bone field especially in the evaluation of metabolic bone diseases. The objective of this study was to develop a rat osteosarcoma model for evaluation of new surgical and molecular methods of treatment for extremity sarcoma. One hundred male SD rats weighing 125.45+/-8.19 g were divided into 5 groups and anesthetized intraperitoneally with 10% chloral hydrate. Orthotopic implantation models of rat osteosarcoma were performed by injecting directly into the SD rat femur with a needle for inoculation with SD tumor cells. In the first step of the experiment, 2x10(5) to 1x10(6) UMR106 cells in 50 microl were injected intraosseously into median or distal part of the femoral shaft and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from ultrasound with findings from necropsia and determining time of survival. In the third stage, the orthotopically implanted tumors and lung nodules were resected entirely, sectioned, and then counter stained with hematoxylin and eosin for histopathologic evaluation. The tumor take rate was 100% for implants with 8x10(5) tumor cells or more, which was much less than the amount required for subcutaneous implantation, with a high lung metastasis rate of 93.0%. Ultrasound and necropsia findings matched closely (r=0.942; p<0.01), which demonstrated that Doppler ultrasonography is a convenient and reliable technique for measuring cancer at any stage. Tumor growth curve showed that orthotopically implanted tumors expanded vigorously with time-lapse, especially in the first 3 weeks. The median time of survival was 38 days and surgical mortality was 0%. The UMR106 cell line has strong carcinogenic capability and high lung metastasis frequency. The present rat

  12. Técnica de suturas ajustables: Resultados Technique of adjustable sutures: Results

    Directory of Open Access Journals (Sweden)

    Lourdes R. Hernández Santos

    2001-06-01

    Full Text Available Se realizó un estudio sensorial y motor preoperatorio y posoperatorio a 84 pacientes que acudieron a la consulta de Visión Binocular con el diagnóstico de estrabismo horizontal a partir de los 13 años de edad. El método estadístico utilizado fue "t" o Chi cuadrado. Nos trazamos como objetivo determinar los resultados posoperatorios de la cirugía de estrabismo realizada con la técnica de suturas ajustables, que fueron los siguientes: el 61 % de los pacientes con exotropía y el 71,4 % con el diagnóstico de exotropía se encontraban en ortotropía a los 6 meses de la intervención. El 71,4 % de los pacientes con esotropía y el 83,3 % con el diagnóstico de esotropía se encontraban en ortotropía al año de la intervención. Esta técnica quirúrgica permite la modificación de la desviación en el posoperatorio inmediato.A preoperative and postoperative sensorial and motor study was conducted among 84 patients who received attention at the consultation room of Binocular Vision with the diagnosis of horizontal strabismus from the age of 13 years old on. The statistical method used was "t" or chi square test. Our objective was to determine the postoperative results of the strabismus surgery performed by the technique of adjustable sutures. The results were as follows: 61 % of the patients with exotropia and 71.4 % with the diagnosis of exotropia were in orthotropia 6 months after the operation. 71.4 % of the patients with exotropia and 83.3 % with the diagnosis of exotropia were in orthotropia a year after the operation. This surgical technique allows the modification of the deviation in the immediate postoperative.

  13. Territories typification technique with use of statistical models

    Science.gov (United States)

    Galkin, V. I.; Rastegaev, A. V.; Seredin, V. V.; Andrianov, A. V.

    2018-05-01

    Territories typification is required for solution of many problems. The results of geological zoning received by means of various methods do not always agree. That is why the main goal of the research given is to develop a technique of obtaining a multidimensional standard classified indicator for geological zoning. In the course of the research, the probabilistic approach was used. In order to increase the reliability of geological information classification, the authors suggest using complex multidimensional probabilistic indicator P K as a criterion of the classification. The second criterion chosen is multidimensional standard classified indicator Z. These can serve as characteristics of classification in geological-engineering zoning. Above mentioned indicators P K and Z are in good correlation. Correlation coefficient values for the entire territory regardless of structural solidity equal r = 0.95 so each indicator can be used in geological-engineering zoning. The method suggested has been tested and the schematic map of zoning has been drawn.

  14. The GRIM Test : A Simple Technique Detects Numerous Anomalies in the Reporting of Results in Psychology

    NARCIS (Netherlands)

    Brown, Nicholas J. L.; Heathers, James A. J.

    2017-01-01

    We present a simple mathematical technique that we call granularity-related inconsistency of means (GRIM) for verifying the summary statistics of research reports in psychology. This technique evaluates whether the reported means of integer data such as Likert-type scales are consistent with the

  15. Simplified Model Surgery Technique for Segmental Maxillary Surgeries

    Directory of Open Access Journals (Sweden)

    Namit Nagar

    2011-01-01

    Full Text Available Model surgery is the dental cast version of cephalometric prediction of surgical results. Patients having vertical maxillary excess with prognathism invariably require Lefort I osteotomy with maxillary segmentation and maxillary first premolar extractions during surgery. Traditionally, model surgeries in these cases have been done by sawing the model through the first premolar interproximal area and removing that segment. This clinical innovation employed the use of X-ray film strips as separators in maxillary first premolar interproximal area. The method advocated is a time-saving procedure where no special clinical or laboratory tools, such as plaster saw (with accompanying plaster dust, were required and reusable separators were made from old and discarded X-ray films.

  16. MR-guided biopsies of lesions in the retroperitoneal space: technique and results

    International Nuclear Information System (INIS)

    Zangos, S.; Eichler, K.; Wetter, A.; Lehnert, T.; Hammerstingl, R.; Diebold, T.; Reichel, P.; Herzog, C.; Mack, M.G.; Vogl, T.J.; Hansmann, M.-L.

    2006-01-01

    The purpose of this study was to evaluate the safety and precision of MRI-guided biopsies of retroperitoneal space-occupying tumors in an open low-field system. In 30 patients with indistinct retroperitoneal tumors [paraaortic lesion (n=20), kidney (n=2), suprarenal gland (n=3) and pancreas (n=5)] MR-guided biopsies were performed using a low-field system (0.2 T, Magnetom Concerto, Siemens, Germany). For the monitoring of the biopsies T1-weighted FLASH sequences (TR/TE=160/5 ms; 90 ) were used in all patients and modified FLASH sequences (TR/TE=160/13 ms; 90 ) in ten patients. After positioning of the needle in the tumors 114 biopsy specimens were acquired in coaxial technique with 16-gauge cutting needles (Somatex, Germany). The biopsies were successfully performed in all patients without vascular or organ injuries. The visualization of the aortic blood flow with MRI facilitated the biopsy procedures of paraaortic lesions. The size of the lesions ranged from 1.6 to 7.5 cm. The median distance of the biopsy access path was 10.4 cm. Adequate specimens were obtained in 28 cases (93.3%) resulting in a correct histological classification of 27 lesions (90%). In conclusion, MR-guided biopsies of retroperitoneal lesions using an open low-field system can be performed safely and accurately and is an alternative to CT-guided biopsies. (orig.)

  17. Percutaneous gastrostomy and jejunostomy: Technique, results, and complications in 55 cases

    International Nuclear Information System (INIS)

    Mueller, P.R.; Brown, A.; Saini, S.; Hahn, P.F.; Steiner, E.; Ferrucci, J.T.; Forman, B.H.; Silverman, S.G.

    1987-01-01

    Percutaneous radiologic gastrostomy is a well-described method that has not been widely adopted by radiologists. The authors reviewed their experience to highlight technical points and clinical results. Direct percutaneous gastrostomy was performed in 51 patients and percutaneous jejunostomy in four. Indications for gastrostomy procedures were the need for general nutrition (n = 31), complications of use of a nasogastric feeding tube (n = 7), gastric or small bowel decompression (n = 4) and endoscopic failure (n = 5). The major indication for percutaneous jejunostomy was decompression of small bowel obstruction. Key technical aspects include the use of a novel needle device that tacks the abdominal wall to the stomach, thus assuring a seal between the two structures. In the percutaneous gastrostomies, 18-F Foley catheters were introduced through the tacked portion of the stomach with a Seldinger technique and dilators. For percutaneous jejunostomy, 18-F feeding tubes were placed. All procedures were performed under local anesthesia. The authors conclude that a radiologic percutaneous gastrostomy is a safe and effective procedure and should be pursued aggressively by interventional radiologists

  18. Mapping the temporal pole with a specialized electrode array: technique and preliminary results

    International Nuclear Information System (INIS)

    Abel, Taylor J; Rhone, Ariane E; Nourski, Kirill V; Oya, Hiroyuki; Kawasaki, Hiroto; Howard, Matthew A III; Granner, Mark A; Tranel, Daniel T; Griffiths, Timothy D

    2014-01-01

    Temporopolar cortex plays a crucial role in the pathogenesis of temporal lobe epilepsy and subserves important cognitive functions. Because of its shape and position in the middle cranial fossa, complete electrode coverage of the temporal pole (TP) is difficult to achieve using existing devices. We designed a novel TP electrode array that conforms to the surface of temporopolar cortex and achieves dense electrode coverage of this important brain region. A multi-pronged electrode array was designed that can be placed over the surface of the TP using a straightforward insertion technique. Twelve patients with medically intractable epilepsy were implanted with the TP electrode array for purposes of seizure localization. Select patients underwent cognitive mapping by electrocorticographic (ECoG) recording from the TP during a naming task. Use of the array resulted in excellent TP electrode coverage in all patients. High quality ECoG data were consistently obtained for purposes of delineating seizure activity and functional mapping. During a naming task, significant increases in ECoG power were observed within localized subregions of the TP. One patient developed a transient neurological deficit thought to be related to the mass effect of multiple intracranial recording arrays, including the TP array. This deficit resolved following removal of all electrodes. The TP electrode array overcomes limitations of existing devices and enables clinicians and researchers to obtain optimal multi-site recordings from this important brain region. (paper)

  19. Development of a New Technique to Assess Susceptibility to Predation Resulting from Sublethal Stresses (Indirect Mortality)

    Energy Technology Data Exchange (ETDEWEB)

    Cada, G.F.

    2003-08-25

    Fish that pass through a hydroelectric turbine may not be killed directly, but may nonetheless experience sublethal stresses that will increase their susceptibility to predators (indirect mortality). There is a need to develop reliable tests for indirect mortality so that the full consequences of passage through turbines (and other routes around a hydroelectric dam) can be assessed. We evaluated a new technique for assessing indirect mortality, based on a behavioral response to a startling stimulus (akin to perceiving an approaching predator). We compare this technique to the standard predator preference test. The behavioral response is a rapid movement commonly referred to as a startle response, escape response, or C-shape, based on the characteristic body position assumed by the fish. When viewed from above, a startled fish bends into a C-shape, then springs back and swims away in a direction different from its original orientation. This predator avoidance (escape) behavior can be compromised by sublethal stresses that temporarily stun or disorient the fish. We subjected striped shiners and fathead minnows to varying intensities of either turbulence (10-, 20- or 30-min) or 2-min exposures to a fish anesthetic (100 or 200 mg/L of tricaine methanesulfonate), and evaluated their subsequent behavior. Individual fish were given a startle stimulus and filmed with a high-speed video camera. Each fish was startled and filmed twice before being stressed, and then at 1-, 5-, 15-, and 30-min post-exposure. The resulting image files were analyzed for a variety of behavioral measures including: presence of a response, time to first reaction, duration of reaction, time to formation of maximum C-shape, time to completion of C-shape, and completeness of C-shape. The most immediate measure of potential changes in fish behavior was whether stressed fish exhibited a startle response. For striped shiners, the number of fish not responding to the stimulus was significantly different

  20. Preoperative trans-arterial embolization for spinal tumor: embolization techniques and results

    International Nuclear Information System (INIS)

    Shi Haibin; Xu Daizhe

    2000-01-01

    Objective: To analyze the technique and to evaluate the safety and value of preoperative trans-arterial embolization of hypervascular spinal tumors. Methods: Eighteen patients with hypervascular spinal tumors underwent trans-arterial embolization before surgery. They arose intradural in six patients and extradural in 12. Thirty-one arteries were embolized with polyvinyl alcohol (PVA) particles (150-500 μm), of which 18 with additional pieces of gelatin sponge for proximal pedicular embolization. The criteria for judging the effectiveness of embolization were the completeness of tumor removal and estimated blood loss during surgery. Results: Tumor embolization with total occlusion was obtained in eight patients, second to total in seven, subtotal in one, and partial in two. There were no symptomatic complications associated with embolization. Tumors were totally removed in 17 patients and nearly totally removed in one. The average estimated blood loss during surgery was 1100 ml (range, 200-6000 ml) for all 18 patients, and 1540 ml in patients with extradural tumors. Conclusions: Preoperative embolization of hypervascular spinal tumors is safe and effective. It can make complete resection of a tumor possible and can make an unresectable tumor resectable. Superselection or flow control is necessary to achieve effective devascularization and avoid complications

  1. External radiotherapy in macular degeneration: Our technique, dosimetric calculation, and preliminary results

    International Nuclear Information System (INIS)

    Akmansu, M.; Dirican, Bahar; Oeztuerk, Berrin; Egehan, Ibrahim; Subasi, Mahmut; Or, Meral

    1998-01-01

    Purpose: This study was performed to determine the toxicity and efficacy of external-beam radiotherapy in patients with age-related subfoveal neovascularization. Methods and Materials: Between January 1996 and September 1996, 25 patients with a mean age of 70.5 (60-84) years were enrolled. All patients underwent fluorescein angiographic evaluation and documentation of their neovascular disease prior to irradiation. A total of 25 patients were treated with a total dose of 12 Gy in 6 fractions over 8 days. We used a lens-sparing technique and patients were treated with a single lateral 6-MV photon beam. To assess the risk of radiation carcinogenesis after treatment of age-related subfoveal neovascularization, we estimated the effective dose for a standard patient on the basis of tissue-weighting factors as defined by the International Commission on Radiological Protection (ICRP). The calculations were made with TLD on a male randophantom. The lens dose was found to be 0.217 Gy per fraction. Results: No significant acute morbidity was noted. Visual acuity was maintained or improved in 76% and 80% of treated patients at their 1- and 3-month follow-up examinations, respectively. On angiographic imaging, there was stabilization of subfoveal neovascular membranes in 23 patients (92%) at 3 months after irradiation. Conclusion: Our observations on these 25 patients in this study indicate that many patients will have improved or stable vision after radiotherapy treatment with low-dose irradiation

  2. Results of a M = 5.3 heat transfer test of the integrated vehicle using phase-change paint techniques on the 0.0175-scale model 56-OTS in the NASA/Ames Research Center 3.5-foot hypersonic wind tunnel

    Science.gov (United States)

    Marroquin, J.

    1985-01-01

    An experimental investigation was performed in the NASA/Ames Research Center 3.5-foot Hypersonic Wind Tunnel to obtain supersonic heat-distribution data in areas between the orbiter and external tank using phase-change paint techniques. The tests used Novamide SSV Model 56-OTS in the first and second-stage ascent configurations. Data were obtained at a nominal Mach number of 5.3 and a Reynolds number per foot of 5 x 10 to the 6th power with angles of attack of 0 deg, +/- 5 deg, and sideslip angles of 0 deg and +/- 5 deg.

  3. The uncertainty analysis of model results a practical guide

    CERN Document Server

    Hofer, Eduard

    2018-01-01

    This book is a practical guide to the uncertainty analysis of computer model applications. Used in many areas, such as engineering, ecology and economics, computer models are subject to various uncertainties at the level of model formulations, parameter values and input data. Naturally, it would be advantageous to know the combined effect of these uncertainties on the model results as well as whether the state of knowledge should be improved in order to reduce the uncertainty of the results most effectively. The book supports decision-makers, model developers and users in their argumentation for an uncertainty analysis and assists them in the interpretation of the analysis results.

  4. Integrated approach to model decomposed flow hydrograph using artificial neural network and conceptual techniques

    Science.gov (United States)

    Jain, Ashu; Srinivasulu, Sanaga

    2006-02-01

    This paper presents the findings of a study aimed at decomposing a flow hydrograph into different segments based on physical concepts in a catchment, and modelling different segments using different technique viz. conceptual and artificial neural networks (ANNs). An integrated modelling framework is proposed capable of modelling infiltration, base flow, evapotranspiration, soil moisture accounting, and certain segments of the decomposed flow hydrograph using conceptual techniques and the complex, non-linear, and dynamic rainfall-runoff process using ANN technique. Specifically, five different multi-layer perceptron (MLP) and two self-organizing map (SOM) models have been developed. The rainfall and streamflow data derived from the Kentucky River catchment were employed to test the proposed methodology and develop all the models. The performance of all the models was evaluated using seven different standard statistical measures. The results obtained in this study indicate that (a) the rainfall-runoff relationship in a large catchment consists of at least three or four different mappings corresponding to different dynamics of the underlying physical processes, (b) an integrated approach that models the different segments of the decomposed flow hydrograph using different techniques is better than a single ANN in modelling the complex, dynamic, non-linear, and fragmented rainfall runoff process, (c) a simple model based on the concept of flow recession is better than an ANN to model the falling limb of a flow hydrograph, and (d) decomposing a flow hydrograph into the different segments corresponding to the different dynamics based on the physical concepts is better than using the soft decomposition employed using SOM.

  5. Fuzzy modeling and control of rotary inverted pendulum system using LQR technique

    International Nuclear Information System (INIS)

    Fairus, M A; Mohamed, Z; Ahmad, M N

    2013-01-01

    Rotary inverted pendulum (RIP) system is a nonlinear, non-minimum phase, unstable and underactuated system. Controlling such system can be a challenge and is considered a benchmark in control theory problem. Prior to designing a controller, equations that represent the behaviour of the RIP system must be developed as accurately as possible without compromising the complexity of the equations. Through Takagi-Sugeno (T-S) fuzzy modeling technique, the nonlinear system model is then transformed into several local linear time-invariant models which are then blended together to reproduce, or approximate, the nonlinear system model within local region. A parallel distributed compensation (PDC) based fuzzy controller using linear quadratic regulator (LQR) technique is designed to control the RIP system. The results show that the designed controller able to balance the RIP system

  6. CT coronary angiography: examination technique, clinical results, and outlook on future developments

    International Nuclear Information System (INIS)

    Dewey, M.; Hamm, B.

    2007-01-01

    Multislice computed tomography (MSCT) after intravenous contrast agent administration enables visualization of the coronary arteries with high spatial resolution (voxel sizes down to 0.5 x 0.35 x 0.35 mm3) and a short scan time. Magnetic resonance imaging (MRI) is also intensively studied with respect to the noninvasive detection of coronary artery stenosis and thus the detection of coronary artery disease (CAD) without radiation exposure but is not equal to MSCT at present. This article provides an overview of the historical development of CT coronary angiography from 4-slice CT to 16-slice CT and 64-slice CT. A crucial aspect of this development is the improvement in image quality resulting from shorter breath-hold periods and the reduced gantry rotation time. Other techniques that appear to considerably improve image quality and accuracy and make CT independent of patient heart rates are multisegment reconstruction and dual-source CT. Sublingual nitroglycerin as well as oral or intravenous betablocker administration should be considered in relation to the diagnostic question to be answered and the patient's heart rate. In the studies available CT coronary angiography with at least 12 simultaneous detector rows has a sensitivity of 96.9 % and a specificity of 75.3 % at the patient level. Especially the negative predictive value of CT (94.6 %) emphasizes the idea that this technique may reliably exclude CAD in patients with intermediate pretest likelihood. In the near future, 256-slice CT will allow examination of the entire heart during one heartbeat or even 4D CT scanning with simultaneous assessment of myocardial perfusion. Automatic or semiautomatic software tools will assume a central place in detecting and quantifying coronary artery stenoses and plaques as well as in the analysis of cardiac function in the clinical setting over the next years. Prior to its routine clinical use, the cost-effectiveness of CT coronary angiography must be determined and the

  7. Early Results of Chimney Technique for Type B Aortic Dissections Extending to the Aortic Arch

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chen [Affiliated Hospital of Nantong University, Department of General Surgery (China); Tang, Hanfei; Qiao, Tong; Liu, Changjian; Zhou, Min, E-mail: 813477618@qq.com [The Affiliated Hospital of Nanjing University Medical School, Department of Vascular Surgery, Nanjing Drum Tower Hospital (China)

    2016-01-15

    ObjectiveTo summarize our early experience gained from the chimney technique for type B aortic dissection (TBAD) extending to the aortic arch and to evaluate the aortic remodeling in the follow-up period.MethodsFrom September 2011 to July 2014, 27 consecutive TBAD patients without adequate proximal landing zones were retrograde analyzed. Chimney stent-grafts were deployed parallel to the main endografts to reserve flow to branch vessels while extending the landing zones. In the follow-up period, aortic remodeling was observed with computed tomography angiography.ResultsThe technical success rate was 100 %, and endografts were deployed in zone 0 (n = 3, 11.1 %), zone 1 (n = 18, 66.7 %), and zone 2 (n = 6, 22.2 %). Immediately, proximal endoleaks were detected in 5 patients (18.5 %). During a mean follow-up period of 17.6 months, computed tomography angiography showed all the aortic stent-grafts and chimney grafts to be patent. Favorable remodeling was observed at the level of maximum descending aorta and left subclavian artery with expansion of true lumen (from 18.4 ± 4.8 to 25 ± 0.86 mm, p < 0.001 and 27.1 ± 0.62 to 28.5 ± 0.37 mm, p < 0.001) and depressurization of false lumen (from 23.7 ± 2.7 to 8.7 ± 3.8 mm, p < 0.001, from 5.3 ± 1.2 to 2.1 ± 2.1 mm, p < 0.001). While at the level of maximum abdominal aorta, suboptimal remodeling of the total aorta (from 24.1 ± 0.4 to 23.6 ± 1.5 mm, p = 0.06) and true lumen (from 13.8 ± 0.6 to 14.5 ± 0.4 mm, p = 0.08) was observed.ConclusionBased on our limited experience, the chimney technique with thoracic endovascular repair is demonstrated to be promising for TBAD extending to the arch with favorable aortic remodeling.

  8. Prospective study of the " Inside-Out" arthroscopic ankle ligament technique: Preliminary result.

    Science.gov (United States)

    Nery, Caio; Fonseca, Lucas; Raduan, Fernando; Moreno, Marcus; Baumfeld, Daniel

    2017-03-22

    Lateral ankle ligament injury is among the most common orthopedic injuries. The objective of this study is to present the preliminary prospective results of treatment using the "Inside-Out" variant of the fully arthroscopic Broström-Gould technique. Twenty six patients were included: 20 male and 6 female, aged 19-60 years, mean 41 years. All patients had positive "anterior drawer" and "talar tilt" tests. When necessary, cartilage injuries were treated with microfracture and arthroscopic resection for anterior impingement; three patients had hindfoot varus, on whom Dwyer osteotomy was performed; one patient had peroneal tendinopathy and was treated with tendoscopic debridement and another one had partial injury of the deltoid ligament, which was treated by direct repair. Two arthroscopic surgery portals were used; the anteromedial and anterolateral. After careful inspection of the joint, the anterior surface of the fibula was cleaned to resect the remains of the anterior talo-fibular ligament. An anchor with two sutures was placed on the anterior aspect of the fibula, 1cm from the distal apex of the malleolus. The sutures were passed through the remnant of the anterior talo-fibular ligament as well as the extensor retinaculum using special curved needles. Duncan knots were used to tie the ligament and the inferior extensor retinaculum while the ankle was kept in a neutral position. Patients were kept immobilized non-weight bearing for 2 weeks and were then allowed to start weight bearing in a removable protective boot for 4 weeks. The patients were able to return to sporting activities 6 months after surgery. After a mean follow-up of 27 months (range 21-36 months), patients were functionally evaluated using the American Orthopedics Foot and Ankle Society (AOFAS) ankle score. The mean preoperative value was 58 points, while the mean postoperative value increased to 90 points. One patient had paresthesia in the superficial fibular nerve area, which resolved

  9. Effects of pump recycling technique on stimulated Brillouin scattering threshold: a theoretical model.

    Science.gov (United States)

    Al-Asadi, H A; Al-Mansoori, M H; Ajiya, M; Hitam, S; Saripan, M I; Mahdi, M A

    2010-10-11

    We develop a theoretical model that can be used to predict stimulated Brillouin scattering (SBS) threshold in optical fibers that arises through the effect of Brillouin pump recycling technique. Obtained simulation results from our model are in close agreement with our experimental results. The developed model utilizes single mode optical fiber of different lengths as the Brillouin gain media. For 5-km long single mode fiber, the calculated threshold power for SBS is about 16 mW for conventional technique. This value is reduced to about 8 mW when the residual Brillouin pump is recycled at the end of the fiber. The decrement of SBS threshold is due to longer interaction lengths between Brillouin pump and Stokes wave.

  10. V and V Efforts of Auroral Precipitation Models: Preliminary Results

    Science.gov (United States)

    Zheng, Yihua; Kuznetsova, Masha; Rastaetter, Lutz; Hesse, Michael

    2011-01-01

    Auroral precipitation models have been valuable both in terms of space weather applications and space science research. Yet very limited testing has been performed regarding model performance. A variety of auroral models are available, including empirical models that are parameterized by geomagnetic indices or upstream solar wind conditions, now casting models that are based on satellite observations, or those derived from physics-based, coupled global models. In this presentation, we will show our preliminary results regarding V&V efforts of some of the models.

  11. Machine Learning Techniques for Modelling Short Term Land-Use Change

    Directory of Open Access Journals (Sweden)

    Mileva Samardžić-Petrović

    2017-11-01

    Full Text Available The representation of land use change (LUC is often achieved by using data-driven methods that include machine learning (ML techniques. The main objectives of this research study are to implement three ML techniques, Decision Trees (DT, Neural Networks (NN, and Support Vector Machines (SVM for LUC modeling, in order to compare these three ML techniques and to find the appropriate data representation. The ML techniques are applied on the case study of LUC in three municipalities of the City of Belgrade, the Republic of Serbia, using historical geospatial data sets and considering nine land use classes. The ML models were built and assessed using two different time intervals. The information gain ranking technique and the recursive attribute elimination procedure were implemented to find the most informative attributes that were related to LUC in the study area. The results indicate that all three ML techniques can be used effectively for short-term forecasting of LUC, but the SVM achieved the highest agreement of predicted changes.

  12. Verification Techniques for Parameter Selection and Bayesian Model Calibration Presented for an HIV Model

    Science.gov (United States)

    Wentworth, Mami Tonoe

    Uncertainty quantification plays an important role when making predictive estimates of model responses. In this context, uncertainty quantification is defined as quantifying and reducing uncertainties, and the objective is to quantify uncertainties in parameter, model and measurements, and propagate the uncertainties through the model, so that one can make a predictive estimate with quantified uncertainties. Two of the aspects of uncertainty quantification that must be performed prior to propagating uncertainties are model calibration and parameter selection. There are several efficient techniques for these processes; however, the accuracy of these methods are often not verified. This is the motivation for our work, and in this dissertation, we present and illustrate verification frameworks for model calibration and parameter selection in the context of biological and physical models. First, HIV models, developed and improved by [2, 3, 8], describe the viral infection dynamics of an HIV disease. These are also used to make predictive estimates of viral loads and T-cell counts and to construct an optimal control for drug therapy. Estimating input parameters is an essential step prior to uncertainty quantification. However, not all the parameters are identifiable, implying that they cannot be uniquely determined by the observations. These unidentifiable parameters can be partially removed by performing parameter selection, a process in which parameters that have minimal impacts on the model response are determined. We provide verification techniques for Bayesian model calibration and parameter selection for an HIV model. As an example of a physical model, we employ a heat model with experimental measurements presented in [10]. A steady-state heat model represents a prototypical behavior for heat conduction and diffusion process involved in a thermal-hydraulic model, which is a part of nuclear reactor models. We employ this simple heat model to illustrate verification

  13. Low level waste management: a compilation of models and monitoring techniques. Volume 1

    International Nuclear Information System (INIS)

    Mosier, J.E.; Fowler, J.R.; Barton, C.J.

    1980-04-01

    In support of the National Low-Level Waste (LLW) Management Research and Development Program being carried out at Oak Ridge National Laboratory, Science Applications, Inc., conducted a survey of models and monitoring techniques associated with the transport of radionuclides and other chemical species from LLW burial sites. As a result of this survey, approximately 350 models were identified. For each model the purpose and a brief description are presented. To the extent possible, a point of contact and reference material are identified. The models are organized into six technical categories: atmospheric transport, dosimetry, food chain, groundwater transport, soil transport, and surface water transport. About 4% of the models identified covered other aspects of LLW management and are placed in a miscellaneous category. A preliminary assessment of all these models was performed to determine their ability to analyze the transport of other chemical species. The models that appeared to be applicable are identified. A brief survey of the state-of-the-art techniques employed to monitor LLW burial sites is also presented, along with a very brief discussion of up-to-date burial techniques

  14. Low level waste management: a compilation of models and monitoring techniques. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Mosier, J.E.; Fowler, J.R.; Barton, C.J. (comps.)

    1980-04-01

    In support of the National Low-Level Waste (LLW) Management Research and Development Program being carried out at Oak Ridge National Laboratory, Science Applications, Inc., conducted a survey of models and monitoring techniques associated with the transport of radionuclides and other chemical species from LLW burial sites. As a result of this survey, approximately 350 models were identified. For each model the purpose and a brief description are presented. To the extent possible, a point of contact and reference material are identified. The models are organized into six technical categories: atmospheric transport, dosimetry, food chain, groundwater transport, soil transport, and surface water transport. About 4% of the models identified covered other aspects of LLW management and are placed in a miscellaneous category. A preliminary assessment of all these models was performed to determine their ability to analyze the transport of other chemical species. The models that appeared to be applicable are identified. A brief survey of the state-of-the-art techniques employed to monitor LLW burial sites is also presented, along with a very brief discussion of up-to-date burial techniques.

  15. VNIR spectral modeling of Mars analogue rocks: first results

    Science.gov (United States)

    Pompilio, L.; Roush, T.; Pedrazzi, G.; Sgavetti, M.

    Knowledge regarding the surface composition of Mars and other bodies of the inner solar system is fundamental to understanding of their origin, evolution, and internal structures. Technological improvements of remote sensors and associated implications for planetary studies have encouraged increased laboratory and field spectroscopy research to model the spectral behavior of terrestrial analogues for planetary surfaces. This approach has proven useful during Martian surface and orbital missions, and petrologic studies of Martian SNC meteorites. Thermal emission data were used to suggest two lithologies occurring on Mars surface: basalt with abundant plagioclase and clinopyroxene and andesite, dominated by plagioclase and volcanic glass [1,2]. Weathered basalt has been suggested as an alternative to the andesite interpretation [3,4]. Orbital VNIR spectral imaging data also suggest the crust is dominantly basaltic, chiefly feldspar and pyroxene [5,6]. A few outcrops of ancient crust have higher concentrations of olivine and low-Ca pyroxene, and have been interpreted as cumulates [6]. Based upon these orbital observations future lander/rover missions can be expected to encounter particulate soils, rocks, and rock outcrops. Approaches to qualitative and quantitative analysis of remotely-acquired spectra have been successfully used to infer the presence and abundance of minerals and to discover compositionally associated spectral trends [7-9]. Both empirical [10] and mathematical [e.g. 11-13] methods have been applied, typically with full compositional knowledge, to chiefly particulate samples and as a result cannot be considered as objective techniques for predicting the compositional information, especially for understanding the spectral behavior of rocks. Extending the compositional modeling efforts to include more rocks and developing objective criteria in the modeling are the next required steps. This is the focus of the present investigation. We present results of

  16. Evaluation of mesh morphing and mapping techniques in patient specific modeling of the human pelvis.

    Science.gov (United States)

    Salo, Zoryana; Beek, Maarten; Whyne, Cari Marisa

    2013-01-01

    Robust generation of pelvic finite element models is necessary to understand the variation in mechanical behaviour resulting from differences in gender, aging, disease and injury. The objective of this study was to apply and evaluate mesh morphing and mapping techniques to facilitate the creation and structural analysis of specimen-specific finite element (FE) models of the pelvis. A specimen-specific pelvic FE model (source mesh) was generated following a traditional user-intensive meshing scheme. The source mesh was morphed onto a computed tomography scan generated target surface of a second pelvis using a landmarked-based approach, in which exterior source nodes were shifted to target surface vertices, while constrained along a normal. A second copy of the morphed model was further refined through mesh mapping, in which surface nodes of the initial morphed model were selected in patches and remapped onto the surfaces of the target model. Computed tomography intensity based material properties were assigned to each model. The source, target, morphed and mapped models were analyzed under axial compression using linear static FE analysis and their strain distributions evaluated. Morphing and mapping techniques were effectively applied to generate good quality geometrically complex specimen-specific pelvic FE models. Mapping significantly improved strain concurrence with the target pelvis FE model. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Evaluation of mesh morphing and mapping techniques in patient specific modelling of the human pelvis.

    Science.gov (United States)

    Salo, Zoryana; Beek, Maarten; Whyne, Cari Marisa

    2012-08-01

    Robust generation of pelvic finite element models is necessary to understand variation in mechanical behaviour resulting from differences in gender, aging, disease and injury. The objective of this study was to apply and evaluate mesh morphing and mapping techniques to facilitate the creation and structural analysis of specimen-specific finite element (FE) models of the pelvis. A specimen-specific pelvic FE model (source mesh) was generated following a traditional user-intensive meshing scheme. The source mesh was morphed onto a computed tomography scan generated target surface of a second pelvis using a landmarked-based approach, in which exterior source nodes were shifted to target surface vertices, while constrained along a normal. A second copy of the morphed model was further refined through mesh mapping, in which surface nodes of the initial morphed model were selected in patches and remapped onto the surfaces of the target model. Computed tomography intensity-based material properties were assigned to each model. The source, target, morphed and mapped models were analyzed under axial compression using linear static FE analysis, and their strain distributions were evaluated. Morphing and mapping techniques were effectively applied to generate good quality and geometrically complex specimen-specific pelvic FE models. Mapping significantly improved strain concurrence with the target pelvis FE model. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Rotational Acceleration during Head Impact Resulting from Different Judo Throwing Techniques

    OpenAIRE

    MURAYAMA, Haruo; HITOSUGI, Masahito; MOTOZAWA, Yasuki; OGINO, Masahiro; KOYAMA, Katsuhiro

    2014-01-01

    Most severe head injuries in judo are reported as acute subdural hematoma. It is thus necessary to examine the rotational acceleration of the head to clarify the mechanism of head injuries. We determined the rotational acceleration of the head when the subject is thrown by judo techniques. One Japanese male judo expert threw an anthropomorphic test device using two throwing techniques, Osoto-gari and Ouchigari. Rotational and translational head accelerations were measured with and without an ...

  19. Results of a nuclear power plant Application of a new technique for human error analysis (ATHEANA)

    International Nuclear Information System (INIS)

    Forester, J.A.; Whitehead, D.W.; Kolaczkowski, A.M.; Thompson, C.M.

    1997-01-01

    A new method to analyze human errors has been demonstrated at a pressurized water reactor (PWR) nuclear power plant. This was the first application of the new method referred to as A Technique for Human Error Analysis (ATHEANA). The main goals of the demonstration were to test the ATHEANA process as described in the frame-of-reference manual and the implementation guideline, test a training package developed for the method, test the hypothesis that plant operators and trainers have significant insight into the error-forcing-contexts (EFCs) that can make unsafe actions (UAs) more likely, and to identify ways to improve the method and its documentation. A set of criteria to evaluate the open-quotes successclose quotes of the ATHEANA method as used in the demonstration was identified. A human reliability analysis (HRA) team was formed that consisted of an expert in probabilistic risk assessment (PRA) with some background in HRA (not ATHEANA) and four personnel from the nuclear power plant. Personnel from the plant included two individuals from their PRA staff and two individuals from their training staff. Both individuals from training are currently licensed operators and one of them was a senior reactor operator open-quotes on shiftclose quotes until a few months before the demonstration. The demonstration was conducted over a 5 month period and was observed by members of the Nuclear Regulatory Commission's ATHEANA development team, who also served as consultants to the HRA team when necessary. Example results of the demonstration to date, including identified human failure events (HFEs), UAs, and EFCs are discussed. Also addressed is how simulator exercises are used in the ATHEANA demonstration project

  20. Laparoscopic inguinal preperitoneal injection--novel technique for inguinal hernia repair: preliminary results of experimental study.

    Science.gov (United States)

    Kozlov, Yury; Novogilov, Vladimir; Rasputin, Andrey; Podkamenev, Alexey; Krasnov, Pavel; Weber, Irina; Solovjev, Alexey

    2012-04-01

    Inguinal hernia repair is the most common procedure in pediatric surgery. Suture techniques for laparoscopic inguinal hernia repair in children are easy to perform and popular with a low recurrence rate. The aim of this study was to evaluate the effect of laparoscopic preperitoneal injection of three-dimensional gel on closing of the inguinal hernia sac (IHS) in laboratory animals. With the animals under general anesthesia, we performed peritoneoscopy in 12 male Chinchilla rabbits weighing 1200-1400 g. The endoscope was introduced into the abdominal cavity, and bilateral deep inguinal rings were identified. A Tuohy needle with the injectable polymeric bulking agent DAM+™ (three-dimensional polyacrylamide gel with silver ions [Argiform(®) from Bioform(®)]) was introduced preperitoneally. The implant was then injected across the entire orifice of the deep inguinal rings and draped over the cord structures. After completion of bilateral repairs, the rabbits were extubated and observed in the animal laboratory. Then the second laparoscopy was performed 6 months later, and the deep inguinal rings were inspected. The postoperative course was uneventful in all the animals. At the second laparoscopy no reopening of the entire orifice of the deep inguinal rings was noted. Accurate placement of the polymeric agent and adequate coverage of the vas deferens were accomplished in all the animals. This study demonstrates that the biopolymeric implant gives good postoperative results and a stable trend of closing the IHS in long-term follow-up. In conclusion, we hope that injectable polymeric bulking agents can be used for treatment of inguinal hernias of pediatric patients after additional animal and human research.

  1. Ionospheric scintillation forecasting model based on NN-PSO technique

    Science.gov (United States)

    Sridhar, M.; Venkata Ratnam, D.; Padma Raju, K.; Sai Praharsha, D.; Saathvika, K.

    2017-09-01

    The forecasting and modeling of ionospheric scintillation effects are crucial for precise satellite positioning and navigation applications. In this paper, a Neural Network model, trained using Particle Swarm Optimization (PSO) algorithm, has been implemented for the prediction of amplitude scintillation index (S4) observations. The Global Positioning System (GPS) and Ionosonde data available at Darwin, Australia (12.4634° S, 130.8456° E) during 2013 has been considered. The correlation analysis between GPS S4 and Ionosonde drift velocities (hmf2 and fof2) data has been conducted for forecasting the S4 values. The results indicate that forecasted S4 values closely follow the measured S4 values for both the quiet and disturbed conditions. The outcome of this work will be useful for understanding the ionospheric scintillation phenomena over low latitude regions.

  2. Experimental investigation of the predictive capabilities of data driven modeling techniques in hydrology - Part 1: Concepts and methodology

    Directory of Open Access Journals (Sweden)

    A. Elshorbagy

    2010-10-01

    Full Text Available A comprehensive data driven modeling experiment is presented in a two-part paper. In this first part, an extensive data-driven modeling experiment is proposed. The most important concerns regarding the way data driven modeling (DDM techniques and data were handled, compared, and evaluated, and the basis on which findings and conclusions were drawn are discussed. A concise review of key articles that presented comparisons among various DDM techniques is presented. Six DDM techniques, namely, neural networks, genetic programming, evolutionary polynomial regression, support vector machines, M5 model trees, and K-nearest neighbors are proposed and explained. Multiple linear regression and naïve models are also suggested as baseline for comparison with the various techniques. Five datasets from Canada and Europe representing evapotranspiration, upper and lower layer soil moisture content, and rainfall-runoff process are described and proposed, in the second paper, for the modeling experiment. Twelve different realizations (groups from each dataset are created by a procedure involving random sampling. Each group contains three subsets; training, cross-validation, and testing. Each modeling technique is proposed to be applied to each of the 12 groups of each dataset. This way, both prediction accuracy and uncertainty of the modeling techniques can be evaluated. The description of the datasets, the implementation of the modeling techniques, results and analysis, and the findings of the modeling experiment are deferred to the second part of this paper.

  3. Testing the ISP method with the PARIO device: Accuracy of results and influence of homogenization technique

    Science.gov (United States)

    Durner, Wolfgang; Huber, Magdalena; Yangxu, Li; Steins, Andi; Pertassek, Thomas; Göttlein, Axel; Iden, Sascha C.; von Unold, Georg

    2017-04-01

    The particle-size distribution (PSD) is one of the main properties of soils. To determine the proportions of the fine fractions silt and clay, sedimentation experiments are used. Most common are the Pipette and Hydrometer method. Both need manual sampling at specific times. Both are thus time-demanding and rely on experienced operators. Durner et al. (Durner, W., S.C. Iden, and G. von Unold (2017): The integral suspension pressure method (ISP) for precise particle-size analysis by gravitational sedimentation, Water Resources Research, doi:10.1002/2016WR019830) recently developed the integral suspension method (ISP) method, which is implemented in the METER Group device PARIOTM. This new method estimates continuous PSD's from sedimentation experiments by recording the temporal evolution of the suspension pressure at a certain measurement depth in a sedimentation cylinder. It requires no manual interaction after start and thus no specialized training of the lab personnel. The aim of this study was to test the precision and accuracy of new method with a variety of materials, to answer the following research questions: (1) Are the results obtained by PARIO reliable and stable? (2) Are the results affected by the initial mixing technique to homogenize the suspension, or by the presence of sand in the experiment? (3) Are the results identical to the one that are obtained with the Pipette method as reference method? The experiments were performed with a pure quartz silt material and four real soil materials. PARIO measurements were done repetitively on the same samples in a temperature-controlled lab to characterize the repeatability of the measurements. Subsequently, the samples were investigated by the pipette method to validate the results. We found that the statistical error for silt fraction from replicate and repetitive measurements was in the range of 1% for the quartz material to 3% for soil materials. Since the sand fractions, as in any sedimentation method, must

  4. Verification of aseismic design model by using experimental results

    International Nuclear Information System (INIS)

    Mizuno, N.; Sugiyama, N.; Suzuki, T.; Shibata, Y.; Miura, K.; Miyagawa, N.

    1985-01-01

    A lattice model is applied as an analysis model for an aseismic design of the Hamaoka nuclear reactor building. With object to verify an availability of this design model, two reinforced concrete blocks are constructed on the ground and the forced vibration tests are carried out. The test results are well followed by simulation analysis using the lattice model. Damping value of the ground obtained from the test is more conservative than the design value. (orig.)

  5. Prediction of Monthly Summer Monsoon Rainfall Using Global Climate Models Through Artificial Neural Network Technique

    Science.gov (United States)

    Nair, Archana; Singh, Gurjeet; Mohanty, U. C.

    2018-01-01

    The monthly prediction of summer monsoon rainfall is very challenging because of its complex and chaotic nature. In this study, a non-linear technique known as Artificial Neural Network (ANN) has been employed on the outputs of Global Climate Models (GCMs) to bring out the vagaries inherent in monthly rainfall prediction. The GCMs that are considered in the study are from the International Research Institute (IRI) (2-tier CCM3v6) and the National Centre for Environmental Prediction (Coupled-CFSv2). The ANN technique is applied on different ensemble members of the individual GCMs to obtain monthly scale prediction over India as a whole and over its spatial grid points. In the present study, a double-cross-validation and simple randomization technique was used to avoid the over-fitting during training process of the ANN model. The performance of the ANN-predicted rainfall from GCMs is judged by analysing the absolute error, box plots, percentile and difference in linear error in probability space. Results suggest that there is significant improvement in prediction skill of these GCMs after applying the ANN technique. The performance analysis reveals that the ANN model is able to capture the year to year variations in monsoon months with fairly good accuracy in extreme years as well. ANN model is also able to simulate the correct signs of rainfall anomalies over different spatial points of the Indian domain.

  6. The Effect of Group Investigation Learning Model with Brainstroming Technique on Students Learning Outcomes

    Directory of Open Access Journals (Sweden)

    Astiti Kade kAyu

    2018-01-01

    Full Text Available This study aims to determine the effect of group investigation (GI learning model with brainstorming technique on student physics learning outcomes (PLO compared to jigsaw learning model with brainstroming technique. The learning outcome in this research are the results of learning in the cognitive domain. The method used in this research is experiment with Randomised Postest Only Control Group Design. Population in this research is all students of class XI IPA SMA Negeri 9 Kupang year lesson 2015/2016. The selected sample are 40 students of class XI IPA 1 as the experimental class and 38 students of class XI IPA 2 as the control class using simple random sampling technique. The instrument used is 13 items description test. The first hypothesis was tested by using two tailed t-test. From that, it is obtained that H0 rejected which means there are differences of students physics learning outcome. The second hypothesis was tested using one tailed t-test. It is obtained that H0 rejected which means the students PLO in experiment class were higher than control class. Based on the results of this study, researchers recommend the use of GI learning models with brainstorming techniques to improve PLO, especially in the cognitive domain.

  7. Comparison of two stochastic techniques for reliable urban runoff prediction by modeling systematic errors

    DEFF Research Database (Denmark)

    Del Giudice, Dario; Löwe, Roland; Madsen, Henrik

    2015-01-01

    from different fields and have not yet been compared in environmental modeling. To compare the two approaches, we develop a unifying terminology, evaluate them theoretically, and apply them to conceptual rainfall-runoff modeling in the same drainage system. Our results show that both approaches can......In urban rainfall-runoff, commonly applied statistical techniques for uncertainty quantification mostly ignore systematic output errors originating from simplified models and erroneous inputs. Consequently, the resulting predictive uncertainty is often unreliable. Our objective is to present two...... approaches which use stochastic processes to describe systematic deviations and to discuss their advantages and drawbacks for urban drainage modeling. The two methodologies are an external bias description (EBD) and an internal noise description (IND, also known as stochastic gray-box modeling). They emerge...

  8. Seasonal differences in the subjective assessment of outdoor thermal conditions and the impact of analysis techniques on the obtained results

    Science.gov (United States)

    Kántor, Noémi; Kovács, Attila; Takács, Ágnes

    2016-11-01

    Wide research attention has been paid in the last two decades to the thermal comfort conditions of different outdoor and semi-outdoor urban spaces. Field studies were conducted in a wide range of geographical regions in order to investigate the relationship between the thermal sensation of people and thermal comfort indices. Researchers found that the original threshold values of these indices did not describe precisely the actual thermal sensation patterns of subjects, and they reported neutral temperatures that vary among nations and with time of the year. For that reason, thresholds of some objective indices were rescaled and new thermal comfort categories were defined. This research investigates the outdoor thermal perception patterns of Hungarians regarding the Physiologically Equivalent Temperature ( PET) index, based on more than 5800 questionnaires. The surveys were conducted in the city of Szeged on 78 days in spring, summer, and autumn. Various, frequently applied analysis approaches (simple descriptive technique, regression analysis, and probit models) were adopted to reveal seasonal differences in the thermal assessment of people. Thermal sensitivity and neutral temperatures were found to be significantly different, especially between summer and the two transient seasons. Challenges of international comparison are also emphasized, since the results prove that neutral temperatures obtained through different analysis techniques may be considerably different. The outcomes of this study underline the importance of the development of standard measurement and analysis methodologies in order to make future studies comprehensible, hereby facilitating the broadening of the common scientific knowledge about outdoor thermal comfort.

  9. Application of nonlinear forecasting techniques for meteorological modeling

    Directory of Open Access Journals (Sweden)

    V. Pérez-Muñuzuri

    2000-10-01

    Full Text Available A nonlinear forecasting method was used to predict the behavior of a cloud coverage time series several hours in advance. The method is based on the reconstruction of a chaotic strange attractor using four years of cloud absorption data obtained from half-hourly Meteosat infrared images from Northwestern Spain. An exhaustive nonlinear analysis of the time series was carried out to reconstruct the phase space of the underlying chaotic attractor. The forecast values are used by a non-hydrostatic meteorological model ARPS for daily weather prediction and their results compared with surface temperature measurements from a meteorological station and a vertical sounding. The effect of noise in the time series is analyzed in terms of the prediction results.Key words: Meterology and atmospheric dynamics (mesoscale meteorology; general – General (new fields

  10. Application of nonlinear forecasting techniques for meteorological modeling

    Directory of Open Access Journals (Sweden)

    V. Pérez-Muñuzuri

    Full Text Available A nonlinear forecasting method was used to predict the behavior of a cloud coverage time series several hours in advance. The method is based on the reconstruction of a chaotic strange attractor using four years of cloud absorption data obtained from half-hourly Meteosat infrared images from Northwestern Spain. An exhaustive nonlinear analysis of the time series was carried out to reconstruct the phase space of the underlying chaotic attractor. The forecast values are used by a non-hydrostatic meteorological model ARPS for daily weather prediction and their results compared with surface temperature measurements from a meteorological station and a vertical sounding. The effect of noise in the time series is analyzed in terms of the prediction results.

    Key words: Meterology and atmospheric dynamics (mesoscale meteorology; general – General (new fields

  11. A New Profile Learning Model for Recommendation System based on Machine Learning Technique

    Directory of Open Access Journals (Sweden)

    Shereen H. Ali

    2016-03-01

    Full Text Available Recommender systems (RSs have been used to successfully address the information overload problem by providing personalized and targeted recommendations to the end users. RSs are software tools and techniques providing suggestions for items to be of use to a user, hence, they typically apply techniques and methodologies from Data Mining. The main contribution of this paper is to introduce a new user profile learning model to promote the recommendation accuracy of vertical recommendation systems. The proposed profile learning model employs the vertical classifier that has been used in multi classification module of the Intelligent Adaptive Vertical Recommendation (IAVR system to discover the user’s area of interest, and then build the user’s profile accordingly. Experimental results have proven the effectiveness of the proposed profile learning model, which accordingly will promote the recommendation accuracy.

  12. A titration model for evaluating calcium hydroxide removal techniques

    Directory of Open Access Journals (Sweden)

    Mark PHILLIPS

    2015-02-01

    Full Text Available Objective Calcium hydroxide (Ca(OH2 has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical challenges with endodontic treatment. This study used a chemical titration method to measure residual Ca(OH2 left after different endodontic irrigation methods. Material and Methods Eighty-six human canine roots were prepared for obturation. Thirty teeth were filled with known but different amounts of Ca(OH2 for 7 days, which were dissolved out and titrated to quantitate the residual Ca(OH2 recovered from each root to produce a standard curve. Forty-eight of the remaining teeth were filled with equal amounts of Ca(OH2 followed by gross Ca(OH2 removal using hand files and randomized treatment of either: 1 Syringe irrigation; 2 Syringe irrigation with use of an apical file; 3 Syringe irrigation with added 30 s of passive ultrasonic irrigation (PUI, or 4 Syringe irrigation with apical file and PUI (n=12/group. Residual Ca(OH2 was dissolved with glycerin and titrated to measure residual Ca(OH2 left in the root. Results No method completely removed all residual Ca(OH2. The addition of 30 s PUI with or without apical file use removed Ca(OH2 significantly better than irrigation alone. Conclusions This technique allowed quantification of residual Ca(OH2. The use of PUI (with or without apical file resulted in significantly lower Ca(OH2 residue compared to irrigation alone.

  13. In vivo proton MR spectroscopy of normal liver parenchyma: technique and results

    International Nuclear Information System (INIS)

    Mueller, C.; Huebner, F.; Bisdas, S.; Herzog, C.; Hammerstingl, R.M.; Vogl, T.J.; Ackermann, H.; Vorbuchner, M.

    2006-01-01

    Purpose: To analyze the proton magnetic resonance spectroscopic data ( 1 H MRS) of normal liver parenchyma with regard to age, sex, body mass index and location in the liver. Materials and Methods: 45 healthy volunteers age 24 to 65 years were examined with an optimized single-voxel 1 H MRS using a 1.5-T scanner. A spin echo sequence with a TR of 1500 ms and a TE of 135 ms was used, allowing in-phase detection of the choline signal. Weak water suppression was achieved using a chemical shift selective suppression (CHESS) technique. Each examination included the measurement of three voxels with a voxel size of 18 x 18 x 18 mm 3 in different areas of the liver. The volunteers were divided into different age-based groups (young: ≤44 years; older: ≥44 years), BMI (normal weighted: 2 ; obese: >25 kg/m 2 ) and sex. Results: In the acquired spectra different lipid (e.g. [CH 2 ] n ), choline, glutamine, glutamate and glycogenglucose-complex reasonances were detected. The analysis of the spectra, however, only focused on the concentrations of choline and (CH 2 ) n and the relative concentrations of the choline-to-(CH 2 ) n -ratios. In the older volunteers the relative concentration of the choline-to-(CH 2 ) n -ratio was significantly decreased by 0.213±0.193 in comparison to the younger subjects (p=0,031). Further statistical analysis confirmed a significant decrease of the choline-to-(CH 2 ) n -ratio by 0.223±0.180 in obese volunteers compared to volunteers of a standard weight (p=0,016). The significant difference between the choline-to-(CH 2 ) n -ratio female versus male volunteers was calculated with an increase of 0.483±0.172 (p=0,000). The location of the voxel in the liver parenchyma did not yield a signficant difference in the choline-to-(CH 2 ) n -ratio. (orig.)

  14. [Three years results of transvaginal cystocele repair with polypropylene mesh using a tension-free technique].

    Science.gov (United States)

    El Harrech, Y; Ameur, A; Janane, A; Moufide, K; Ghadouane, M; Abbar, M

    2010-01-01

    To evaluate the long term efficacy and safety of transvaginal implantation of a non-resorbable synthetic prosthesis (Gynemesh) for the treatment of cystocele using transvaginal free tension technique. Prospective study of patients that have been submitted to correction of cystocele between April 2004 and July 2007. A prolene mesh was cut to an appropriate size to cover the whole cystocele leaving two tabs on each side. The two tabs of the mesh were then placed in paravaginal spaces, tension free, without stitches. Mesh was used in 31 patients. All patients had a symptomatic cystocele >or= 2 according to Baden-Walker halfway classification. Patients were reviewed initially at 1 and 3 month and then every 6 months. The mean age of the patients was 58 years (range: 47-70 years). Mean parity was 5.8 (range 1-11), and mean weight was 75 kg (range 60-82Kg). All women were postmenopausal. The operation was combined with vaginal hysterectomy in 2 patients, Posterior colporraphy in 2 patients, Perineorrhaphy in 1 patient, Sacrospinous fixation in 2 patients, transobturator tape for stress urinary incontinence in 7 women. Average time of surgery was 23 minutes for cystocele. There were no major complications, such as trauma to the bladder, urethra, bowels, or large vessels in the patient group treated. There was no immediate postoperative complications (up to 7 days) recorded. No hematoma or infection was observed in the operative area. Mesh erosion was detected in one patient. It was treated by excision of the eroded part of the mesh. Mean follow-up was 36.4 months (18 to 52 months). Using our definition of success based on both anatomic and functional outcomes, the overall cure rate was 74.19% (asymptomatic with no or grade 1 cystocele). The improvement rate (asymptomatic with a grade 2 cystocele) was 19.35% and the overall failure rate (symptomatic or with a grade 3 or 4 cystocele) was only 6.4% (2 women). The interposition of a sub-vesical transversal tension

  15. Early Results of the PETTICOAT Technique for the Management of Acute Type A Aortic Dissection.

    Science.gov (United States)

    Kotha, Vamshi Krishna; Pozeg, Zlatko I; Herget, Eric J; Moon, Michael C; Appoo, Jehangir J

    2017-08-01

    Conventional surgical techniques for acute Type A aortic dissection (ATAAD) generally fail to address residual dissection in the descending aorta. The persistence of a false lumen is associated with visceral malperfusion in the acute setting and adverse aortic remodeling in the chronic setting. Hybrid aortic arch repair techniques may improve perioperative and long-term mortality by expanding the true lumen and obliterating the false lumen. However, there is a limit to the extent of aortic coverage due to the concomitant risk of spinal cord ischemia. In Type B dissection, the PETTICOAT (Provisional Extension To Induce Complete Attachment) technique, which entails stent graft coverage of the primary intimal tear followed by bare metal stent placement distally, may improve true lumen caliber and promote false lumen thrombosis without increasing the risk of spinal cord ischemia, as intercostal branches remain perfused through the bare metal stents. The technique of hybrid arch with surgical creation of a Dacron landing zone covering a stent graft in the proximal descending aorta and bare metal stents in the thoraco-abdominal aorta is a promising concept in the treatment of ATAAD.

  16. Limited vs extended face-lift techniques: objective analysis of intraoperative results.

    Science.gov (United States)

    Litner, Jason A; Adamson, Peter A

    2006-01-01

    To compare the intraoperative outcomes of superficial musculoaponeurotic system plication, imbrication, and deep-plane rhytidectomy techniques. Thirty-two patients undergoing primary deep-plane rhytidectomy participated. Each hemiface in all patients was submitted sequentially to 3 progressively more extensive lifts, while other variables were standardized. Four major outcome measures were studied, including the extent of skin redundancy and the repositioning of soft tissues along the malar, mandibular, and cervical vectors of lift. The amount of skin excess was measured without tension from the free edge to a point over the intertragal incisure, along a plane overlying the jawline. Using a soft tissue caliper, repositioning was examined by measurement of preintervention and immediate postintervention distances from dependent points to fixed anthropometric reference points. The mean skin excesses were 10.4, 12.8, and 19.4 mm for the plication, imbrication, and deep-plane lifts, respectively. The greatest absolute soft tissue repositioning was noted along the jawline, with the least in the midface. Analysis revealed significant differences from baseline and between lift types for each of the studied techniques in each of the variables tested. These data support the use of the deep-plane rhytidectomy technique to achieve a superior intraoperative lift relative to comparator techniques.

  17. Results and analysis of the 2008-2009 Insulin Injection Technique Questionnaire survey

    NARCIS (Netherlands)

    De Coninck, Carina; Frid, Anders; Gaspar, Ruth; Hicks, Debbie; Hirsch, Larry; Kreugel, Gillian; Liersch, Jutta; Letondeur, Corinne; Sauvanet, Jean-Pierre; Tubiana, Nadia; Strauss, Kenneth

    Background: The efficacy of injection therapy in diabetes depends on correct injection technique and, to provide patients with guidance in this area, we must understand how they currently inject. Methods: From September 2008 to June 2009, 4352 insulin-injecting Type 1 and Type 2 diabetic patients

  18. Rotation technique for irradiation of the bladder and the results obtained

    Energy Technology Data Exchange (ETDEWEB)

    Backhouse, T W [Coventry and Warwickshire Hospital (UK). Dept. of Radiotherapy and Oncology

    1979-05-01

    An argument is advanced for the use of partial rotational techniques for the treatment of carcinoma of the bladder. One hundred and seventy cases are analysed; the majority were T3 solid transitional cell lesions with an overall (corrected) survival rate of 24.7%. Salvage cystectomy produced a four-year survival rate of 40% when performed within six months of the radiotherapy.

  19. Identifiability Results for Several Classes of Linear Compartment Models.

    Science.gov (United States)

    Meshkat, Nicolette; Sullivant, Seth; Eisenberg, Marisa

    2015-08-01

    Identifiability concerns finding which unknown parameters of a model can be estimated, uniquely or otherwise, from given input-output data. If some subset of the parameters of a model cannot be determined given input-output data, then we say the model is unidentifiable. In this work, we study linear compartment models, which are a class of biological models commonly used in pharmacokinetics, physiology, and ecology. In past work, we used commutative algebra and graph theory to identify a class of linear compartment models that we call identifiable cycle models, which are unidentifiable but have the simplest possible identifiable functions (so-called monomial cycles). Here we show how to modify identifiable cycle models by adding inputs, adding outputs, or removing leaks, in such a way that we obtain an identifiable model. We also prove a constructive result on how to combine identifiable models, each corresponding to strongly connected graphs, into a larger identifiable model. We apply these theoretical results to several real-world biological models from physiology, cell biology, and ecology.

  20. Automatic video segmentation employing object/camera modeling techniques

    NARCIS (Netherlands)

    Farin, D.S.

    2005-01-01

    Practically established video compression and storage techniques still process video sequences as rectangular images without further semantic structure. However, humans watching a video sequence immediately recognize acting objects as semantic units. This semantic object separation is currently not

  1. A Titration Technique for Demonstrating a Magma Replenishment Model.

    Science.gov (United States)

    Hodder, A. P. W.

    1983-01-01

    Conductiometric titrations can be used to simulate subduction-setting volcanism. Suggestions are made as to the use of this technique in teaching volcanic mechanisms and geochemical indications of tectonic settings. (JN)

  2. Modelling skin penetration using the Laplace transform technique.

    Science.gov (United States)

    Anissimov, Y G; Watkinson, A

    2013-01-01

    The Laplace transform is a convenient mathematical tool for solving ordinary and partial differential equations. The application of this technique to problems arising in drug penetration through the skin is reviewed in this paper. © 2013 S. Karger AG, Basel.

  3. Analysis of Multipath Mitigation Techniques with Land Mobile Satellite Channel Model

    Directory of Open Access Journals (Sweden)

    M. Z. H. Bhuiyan J. Zhang

    2012-12-01

    is of utmost importance to analyze the performance of different multipath mitigation techniques in some realistic measurement-based channel models, for example, the Land Mobile Satellite (LMS channel model [1]-[4], developed at the German Aerospace Center (DLR. The DLR LMS channel model is widely used for simulating the positioning accuracy of mobile satellite navigation receivers in urban outdoor scenarios. The main objective of this paper is to present a comprehensive analysis of some of the most promising techniques with the DLR LMS channel model in varying multipath scenarios. Four multipath mitigation techniques are chosen herein for performance comparison, namely, the narrow Early-Minus-Late (nEML, the High Resolution Correlator, the C/N0-based two stage delay tracking technique, and the Reduced Search Space Maximum Likelihood (RSSML delay estimator. The first two techniques are the most popular and traditional ones used in nowadays GNSS receivers, whereas the later two techniques are comparatively new and are advanced techniques, recently proposed by the authors. In addition, the implementation of the RSSML is optimized here for a narrow-bandwidth receiver configuration in the sense that it now requires a significantly less number of correlators and memory than its original implementation. The simulation results show that the reduced-complexity RSSML achieves the best multipath mitigation performance in moderate-to-good carrier-to-noise density ratio with the DLR LMS channel model in varying multipath scenarios.

  4. Composite use of numerical groundwater flow modeling and geoinformatics techniques for monitoring Indus Basin aquifer, Pakistan.

    Science.gov (United States)

    Ahmad, Zulfiqar; Ashraf, Arshad; Fryar, Alan; Akhter, Gulraiz

    2011-02-01

    The integration of the Geographic Information System (GIS) with groundwater modeling and satellite remote sensing capabilities has provided an efficient way of analyzing and monitoring groundwater behavior and its associated land conditions. A 3-dimensional finite element model (Feflow) has been used for regional groundwater flow modeling of Upper Chaj Doab in Indus Basin, Pakistan. The approach of using GIS techniques that partially fulfill the data requirements and define the parameters of existing hydrologic models was adopted. The numerical groundwater flow model is developed to configure the groundwater equipotential surface, hydraulic head gradient, and estimation of the groundwater budget of the aquifer. GIS is used for spatial database development, integration with a remote sensing, and numerical groundwater flow modeling capabilities. The thematic layers of soils, land use, hydrology, infrastructure, and climate were developed using GIS. The Arcview GIS software is used as additive tool to develop supportive data for numerical groundwater flow modeling and integration and presentation of image processing and modeling results. The groundwater flow model was calibrated to simulate future changes in piezometric heads from the period 2006 to 2020. Different scenarios were developed to study the impact of extreme climatic conditions (drought/flood) and variable groundwater abstraction on the regional groundwater system. The model results indicated a significant response in watertable due to external influential factors. The developed model provides an effective tool for evaluating better management options for monitoring future groundwater development in the study area.

  5. A note on the multi model super ensemble technique for reducing forecast errors

    International Nuclear Information System (INIS)

    Kantha, L.; Carniel, S.; Sclavo, M.

    2008-01-01

    The multi model super ensemble (S E) technique has been used with considerable success to improve meteorological forecasts and is now being applied to ocean models. Although the technique has been shown to produce deterministic forecasts that can be superior to the individual models in the ensemble or a simple multi model ensemble forecast, there is a clear need to understand its strengths and limitations. This paper is an attempt to do so in simple, easily understood contexts. The results demonstrate that the S E forecast is almost always better than the simple ensemble forecast, the degree of improvement depending on the properties of the models in the ensemble. However, the skill of the S E forecast with respect to the true forecast depends on a number of factors, principal among which is the skill of the models in the ensemble. As can be expected, if the ensemble consists of models with poor skill, the S E forecast will also be poor, although better than the ensemble forecast. On the other hand, the inclusion of even a single skillful model in the ensemble increases the forecast skill significantly.

  6. Results of the Marine Ice Sheet Model Intercomparison Project, MISMIP

    Directory of Open Access Journals (Sweden)

    F. Pattyn

    2012-05-01

    Full Text Available Predictions of marine ice-sheet behaviour require models that are able to robustly simulate grounding line migration. We present results of an intercomparison exercise for marine ice-sheet models. Verification is effected by comparison with approximate analytical solutions for flux across the grounding line using simplified geometrical configurations (no lateral variations, no effects of lateral buttressing. Unique steady state grounding line positions exist for ice sheets on a downward sloping bed, while hysteresis occurs across an overdeepened bed, and stable steady state grounding line positions only occur on the downward-sloping sections. Models based on the shallow ice approximation, which does not resolve extensional stresses, do not reproduce the approximate analytical results unless appropriate parameterizations for ice flux are imposed at the grounding line. For extensional-stress resolving "shelfy stream" models, differences between model results were mainly due to the choice of spatial discretization. Moving grid methods were found to be the most accurate at capturing grounding line evolution, since they track the grounding line explicitly. Adaptive mesh refinement can further improve accuracy, including fixed grid models that generally perform poorly at coarse resolution. Fixed grid models, with nested grid representations of the grounding line, are able to generate accurate steady state positions, but can be inaccurate over transients. Only one full-Stokes model was included in the intercomparison, and consequently the accuracy of shelfy stream models as approximations of full-Stokes models remains to be determined in detail, especially during transients.

  7. A characteristic study of CCF modeling techniques and optimization of CCF defense strategies

    International Nuclear Information System (INIS)

    Kim, Min Chull

    2000-02-01

    Common Cause Failures (CCFs ) are among the major contributors to risk and core damage frequency (CDF ) from operating nuclear power plants (NPPs ). Our study on CCF focused on the following aspects : 1) a characteristic study on the CCF modeling techniques and 2) development of the optimal CCF defense strategy. Firstly, the characteristics of CCF modeling techniques were studied through sensitivity study of CCF occurrence probability upon system redundancy. The modeling techniques considered in this study include those most widely used worldwide, i.e., beta factor, MGL, alpha factor, and binomial failure rate models. We found that MGL and alpha factor models are essentially identical in terms of the CCF probability. Secondly, in the study for CCF defense, the various methods identified in the previous studies for defending against CCF were classified into five different categories. Based on these categories, we developed a generic method by which the optimal CCF defense strategy can be selected. The method is not only qualitative but also quantitative in nature: the selection of the optimal strategy among candidates is based on the use of analytic hierarchical process (AHP). We applied this method to two motor-driven valves for containment sump isolation in Ulchin 3 and 4 nuclear power plants. The result indicates that the method for developing an optimal CCF defense strategy is effective

  8. HIGHLY-ACCURATE MODEL ORDER REDUCTION TECHNIQUE ON A DISCRETE DOMAIN

    Directory of Open Access Journals (Sweden)

    L. D. Ribeiro

    2015-09-01

    Full Text Available AbstractIn this work, we present a highly-accurate technique of model order reduction applied to staged processes. The proposed method reduces the dimension of the original system based on null values of moment-weighted sums of heat and mass balance residuals on real stages. To compute these sums of weighted residuals, a discrete form of Gauss-Lobatto quadrature was developed, allowing a high degree of accuracy in these calculations. The locations where the residuals are cancelled vary with time and operating conditions, characterizing a desirable adaptive nature of this technique. Balances related to upstream and downstream devices (such as condenser, reboiler, and feed tray of a distillation column are considered as boundary conditions of the corresponding difference-differential equations system. The chosen number of moments is the dimension of the reduced model being much lower than the dimension of the complete model and does not depend on the size of the original model. Scaling of the discrete independent variable related with the stages was crucial for the computational implementation of the proposed method, avoiding accumulation of round-off errors present even in low-degree polynomial approximations in the original discrete variable. Dynamical simulations of distillation columns were carried out to check the performance of the proposed model order reduction technique. The obtained results show the superiority of the proposed procedure in comparison with the orthogonal collocation method.

  9. Planned posterior assisted levitation in severe subluxated cataract: Surgical technique and clinical results

    Directory of Open Access Journals (Sweden)

    Tova Lifshitz

    2012-01-01

    Full Text Available We report the surgical technique and outcome of planned posterior assisted levitation (P-PAL in four cases of subluxated cataract. P-PAL was planned as the preferred approach in all cases. A spatula was inserted via the pars plana, the whole lens was lifted to the anterior chamber and then removed through a scleral tunnel incision. Anterior chamber intraocular lenses were implanted in all cases. All four eyes had severe subluxation of the crystalline lenses with marked phacodonesis. Two eyes had history of blunt trauma, and the other two eyes had severe pseudoexfoliation with spontaneous lens subluxation. Follow-up ranged from 1 to 2 years in three cases. The postoperative visual acuity was 20/80 or better. No intraoperative complications were observed. In conclusion, the P-PAL technique was successfully performed during cataract surgery in four eyes with severe subluxated cataracts. There were no complications over the long-term follow-up.

  10. An experimental result of estimating an application volume by machine learning techniques.

    Science.gov (United States)

    Hasegawa, Tatsuhito; Koshino, Makoto; Kimura, Haruhiko

    2015-01-01

    In this study, we improved the usability of smartphones by automating a user's operations. We developed an intelligent system using machine learning techniques that periodically detects a user's context on a smartphone. We selected the Android operating system because it has the largest market share and highest flexibility of its development environment. In this paper, we describe an application that automatically adjusts application volume. Adjusting the volume can be easily forgotten because users need to push the volume buttons to alter the volume depending on the given situation. Therefore, we developed an application that automatically adjusts the volume based on learned user settings. Application volume can be set differently from ringtone volume on Android devices, and these volume settings are associated with each specific application including games. Our application records a user's location, the volume setting, the foreground application name and other such attributes as learning data, thereby estimating whether the volume should be adjusted using machine learning techniques via Weka.

  11. Fast Spectral Velocity Estimation Using Adaptive Techniques: In-Vivo Results

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Udesen, Jesper

    2007-01-01

    Adaptive spectral estimation techniques are known to provide good spectral resolution and contrast even when the observation window(OW) is very sbort. In this paper two adaptive techniques are tested and compared to the averaged perlodogram (Welch) for blood velocity estimation. The Blood Power...... the blood process over slow-time and averaging over depth to find the power spectral density estimate. In this paper, the two adaptive methods are explained, and performance Is assessed in controlled steady How experiments and in-vivo measurements. The three methods were tested on a circulating How rig...... with a blood mimicking fluid flowing in the tube. The scanning section is submerged in water to allow ultrasound data acquisition. Data was recorded using a BK8804 linear array transducer and the RASMUS ultrasound scanner. The controlled experiments showed that the OW could be significantly reduced when...

  12. Fuel element transfer cask modelling using MCNP technique

    International Nuclear Information System (INIS)

    Rosli Darmawan

    2009-01-01

    Full text: After operating for more than 25 years, some of the Reaktor TRIGA PUSPATI (RTP) fuel elements would have been depleted. A few addition and fuel reconfiguration exercises have to be conducted in order to maintain RTP capacity. Presently, RTP spent fuels are stored at the storage area inside RTP tank. The need to transfer the fuel element outside of RTP tank may be prevalence in the near future. The preparation shall be started from now. A fuel element transfer cask has been designed according to the recommendation by the fuel manufacturer and experience of other countries. A modelling using MCNP code has been conducted to analyse the design. The result shows that the design of transfer cask fuel element is safe for handling outside the RTP tank according to recent regulatory requirement. (author)

  13. Fuel Element Transfer Cask Modelling Using MCNP Technique

    International Nuclear Information System (INIS)

    Darmawan, Rosli; Topah, Budiman Naim

    2010-01-01

    After operating for more than 25 years, some of the Reaktor TRIGA Puspati (RTP) fuel elements would have been depleted. A few addition and fuel reconfiguration exercises have to be conducted in order to maintain RTP capacity. Presently, RTP spent fuels are stored at the storage area inside RTP tank. The need to transfer the fuel element outside of RTP tank may be prevalence in the near future. The preparation shall be started from now. A fuel element transfer cask has been designed according to the recommendation by the fuel manufacturer and experience of other countries. A modelling using MCNP code has been conducted to analyse the design. The result shows that the design of transfer cask fuel element is safe for handling outside the RTP tank according to recent regulatory requirement.

  14. Results of the activities of the Scientific and Technical Coordination Council for Radiation Technique and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Sille, A K [Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow

    1977-03-01

    It is reported on the activities of the Scientific and Technical Coordination Council for Radiation Technique and Technology (STCC-RTT) of the CMEA Permanent Commission for the Peaceful Uses of Atomic Energy according to the programme 1971 to 1975. The STCC-RTT is concerned with technical applications such as radiation sterilization, food irradiation, radiation-induced chemical processes etc. The main tasks which have to be solved within the period from 1976 to 1980 are outlined.

  15. Proposal of a congestion control technique in LAN networks using an econometric model ARIMA

    Directory of Open Access Journals (Sweden)

    Joaquín F Sánchez

    2017-01-01

    Full Text Available Hasty software development can produce immediate implementations with source code unnecessarily complex and hardly readable. These small kinds of software decay generate a technical debt that could be big enough to seriously affect future maintenance activities. This work presents an analysis technique for identifying architectural technical debt related to non-uniformity of naming patterns; the technique is based on term frequency over package hierarchies. The proposal has been evaluated on projects of two popular organizations, Apache and Eclipse. The results have shown that most of the projects have frequent occurrences of the proposed naming patterns, and using a graph model and aggregated data could enable the elaboration of simple queries for debt identification. The technique has features that favor its applicability on emergent architectures and agile software development.

  16. Parallel-scanning tomosynthesis using a slot scanning technique: Fixed-focus reconstruction and the resulting image quality

    International Nuclear Information System (INIS)

    Shibata, Koichi; Notohara, Daisuke; Sakai, Takihito

    2014-01-01

    Purpose: Parallel-scanning tomosynthesis (PS-TS) is a novel technique that fuses the slot scanning technique and the conventional tomosynthesis (TS) technique. This approach allows one to obtain long-view tomosynthesis images in addition to normally sized tomosynthesis images, even when using a system that has no linear tomographic scanning function. The reconstruction technique and an evaluation of the resulting image quality for PS-TS are described in this paper. Methods: The PS-TS image-reconstruction technique consists of several steps (1) the projection images are divided into strips, (2) the strips are stitched together to construct images corresponding to the reconstruction plane, (3) the stitched images are filtered, and (4) the filtered stitched images are back-projected. In the case of PS-TS using the fixed-focus reconstruction method (PS-TS-F), one set of stitched images is used for the reconstruction planes at all heights, thus avoiding the necessity of repeating steps (1)–(3). A physical evaluation of the image quality of PS-TS-F compared with that of the conventional linear TS was performed using a R/F table (Sonialvision safire, Shimadzu Corp., Kyoto, Japan). The tomographic plane with the best theoretical spatial resolution (the in-focus plane, IFP) was set at a height of 100 mm from the table top by adjusting the reconstruction program. First, the spatial frequency response was evaluated at heights of −100, −50, 0, 50, 100, and 150 mm from the IFP using the edge of a 0.3-mm-thick copper plate. Second, the spatial resolution at each height was visually evaluated using an x-ray test pattern (Model No. 38, PTW Freiburg, Germany). Third, the slice sensitivity at each height was evaluated via the wire method using a 0.1-mm-diameter tungsten wire. Phantom studies using a knee phantom and a whole-body phantom were also performed. Results: The spatial frequency response of PS-TS-F yielded the best results at the IFP and degraded slightly as the

  17. Parallel-scanning tomosynthesis using a slot scanning technique: Fixed-focus reconstruction and the resulting image quality

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Koichi, E-mail: shibatak@suzuka-u.ac.jp [Department of Radiological Technology, Faculty of Health Science, Suzuka University of Medical Science 1001-1, Kishioka-cho, Suzuka 510-0293 (Japan); Notohara, Daisuke; Sakai, Takihito [R and D Department, Medical Systems Division, Shimadzu Corporation 1, Nishinokyo-Kuwabara-cho, Nakagyo-ku, Kyoto 604-8511 (Japan)

    2014-11-01

    Purpose: Parallel-scanning tomosynthesis (PS-TS) is a novel technique that fuses the slot scanning technique and the conventional tomosynthesis (TS) technique. This approach allows one to obtain long-view tomosynthesis images in addition to normally sized tomosynthesis images, even when using a system that has no linear tomographic scanning function. The reconstruction technique and an evaluation of the resulting image quality for PS-TS are described in this paper. Methods: The PS-TS image-reconstruction technique consists of several steps (1) the projection images are divided into strips, (2) the strips are stitched together to construct images corresponding to the reconstruction plane, (3) the stitched images are filtered, and (4) the filtered stitched images are back-projected. In the case of PS-TS using the fixed-focus reconstruction method (PS-TS-F), one set of stitched images is used for the reconstruction planes at all heights, thus avoiding the necessity of repeating steps (1)–(3). A physical evaluation of the image quality of PS-TS-F compared with that of the conventional linear TS was performed using a R/F table (Sonialvision safire, Shimadzu Corp., Kyoto, Japan). The tomographic plane with the best theoretical spatial resolution (the in-focus plane, IFP) was set at a height of 100 mm from the table top by adjusting the reconstruction program. First, the spatial frequency response was evaluated at heights of −100, −50, 0, 50, 100, and 150 mm from the IFP using the edge of a 0.3-mm-thick copper plate. Second, the spatial resolution at each height was visually evaluated using an x-ray test pattern (Model No. 38, PTW Freiburg, Germany). Third, the slice sensitivity at each height was evaluated via the wire method using a 0.1-mm-diameter tungsten wire. Phantom studies using a knee phantom and a whole-body phantom were also performed. Results: The spatial frequency response of PS-TS-F yielded the best results at the IFP and degraded slightly as the

  18. Review of air quality modeling techniques. Volume 8

    International Nuclear Information System (INIS)

    Rosen, L.C.

    1977-01-01

    Air transport and diffusion models which are applicable to the assessment of the environmental effects of nuclear, geothermal, and fossil-fuel electric generation are reviewed. The general classification of models and model inputs are discussed. A detailed examination of the statistical, Gaussian plume, Gaussian puff, one-box and species-conservation-of-mass models is given. Representative models are discussed with attention given to the assumptions, input data requirement, advantages, disadvantages and applicability of each

  19. On the Reliability of Nonlinear Modeling using Enhanced Genetic Programming Techniques

    Science.gov (United States)

    Winkler, S. M.; Affenzeller, M.; Wagner, S.

    The use of genetic programming (GP) in nonlinear system identification enables the automated search for mathematical models that are evolved by an evolutionary process using the principles of selection, crossover and mutation. Due to the stochastic element that is intrinsic to any evolutionary process, GP cannot guarantee the generation of similar or even equal models in each GP process execution; still, if there is a physical model underlying to the data that are analyzed, then GP is expected to find these structures and produce somehow similar results. In this paper we define a function for measuring the syntactic similarity of mathematical models represented as structure trees; using this similarity function we compare the results produced by GP techniques for a data set representing measurement data of a BMW Diesel engine.

  20. Structural and geochemical techniques for the hydrogeological characterisation and stochastic modelling of fractured media

    International Nuclear Information System (INIS)

    Vela, A.; Elorza, F.J.; Florez, F.; Paredes, C.; Mazadiego, L.; Llamas, J.F.; Perez, E.; Vives, L.; Carrera, J.; Munoz, A.; De Vicente, G.; Casquet, C.

    1999-01-01

    Safety analysis of radioactive waste storage systems require fractured rock studies. The performance assessment studies of this type of problems include the development of radionuclide flow and transport models to predict the evolution of possible contaminants released from the repository to the biosphere. The methodology developed in the HIDROBAP project and some results obtained with its application in El Berrocal granite batholith are presented. It integrates modern tools belonging to different disciplines. A Discrete Fracture Network model (DFT) was selected to simulate the fractured medium and a 3D finite element flow and transport model that includes the inverse problem techniques has been coupled to the DFT model to simulate the water movement trough the fracture network system. Preliminary results show that this integrated methodology can be very useful for the hydrogeological characterisation of rock fractured media. (author)

  1. Electromagnetic interference modeling and suppression techniques in variable-frequency drive systems

    Science.gov (United States)

    Yang, Le; Wang, Shuo; Feng, Jianghua

    2017-11-01

    Electromagnetic interference (EMI) causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive (VFD) systems. Unlike fundamental frequency components in motor drive systems, high-frequency EMI noise, coupled with the parasitic parameters of the trough system, are difficult to analyze and reduce. In this article, EMI modeling techniques for different function units in a VFD system, including induction motors, motor bearings, and rectifierinverters, are reviewed and evaluated in terms of applied frequency range, model parameterization, and model accuracy. The EMI models for the motors are categorized based on modeling techniques and model topologies. Motor bearing and shaft models are also reviewed, and techniques that are used to eliminate bearing current are evaluated. Modeling techniques for conventional rectifierinverter systems are also summarized. EMI noise suppression techniques, including passive filter, Wheatstone bridge balance, active filter, and optimized modulation, are reviewed and compared based on the VFD system models.

  2. New Diagnostic, Launch and Model Control Techniques in the NASA Ames HFFAF Ballistic Range

    Science.gov (United States)

    Bogdanoff, David W.

    2012-01-01

    This report presents new diagnostic, launch and model control techniques used in the NASA Ames HFFAF ballistic range. High speed movies were used to view the sabot separation process and the passage of the model through the model splap paper. Cavities in the rear of the sabot, to catch the muzzle blast of the gun, were used to control sabot finger separation angles and distances. Inserts were installed in the powder chamber to greatly reduce the ullage volume (empty space) in the chamber. This resulted in much more complete and repeatable combustion of the powder and hence, in much more repeatable muzzle velocities. Sheets of paper or cardstock, impacting one half of the model, were used to control the amplitudes of the model pitch oscillations.

  3. Examining Interior Grid Nudging Techniques Using Two-Way Nesting in the WRF Model for Regional Climate Modeling

    Science.gov (United States)

    This study evaluates interior nudging techniques using the Weather Research and Forecasting (WRF) model for regional climate modeling over the conterminous United States (CONUS) using a two-way nested configuration. NCEP–Department of Energy Atmospheric Model Intercomparison Pro...

  4. Generalised Chou-Yang model and recent results

    International Nuclear Information System (INIS)

    Fazal-e-Aleem; Rashid, H.

    1995-09-01

    It is shown that most recent results of E710 and UA4/2 collaboration for the total cross section and ρ together with earlier measurements give good agreement with measurements for the differential cross section at 546 and 1800 GeV the framework of Generalised Chou-Yang model. These results are also compared with the predictions of other models. (author). 16 refs, 2 figs

  5. Generalised Chou-Yang model and recent results

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-e-Aleem [International Centre for Theoretical Physics, Trieste (Italy); Rashid, H. [Punjab Univ., Lahore (Pakistan). Centre for High Energy Physics

    1996-12-31

    It is shown that most recent results of E710 and UA4/2 collaboration for the total cross section and {rho} together with earlier measurements give good agreement with measurements for the differential cross section at 546 and 1800 GeV within the framework of Generalised Chou-Yang model. These results are also compared with the predictions of other models. (author) 16 refs.

  6. Generalised Chou-Yang model and recent results

    International Nuclear Information System (INIS)

    Fazal-e-Aleem; Rashid, H.

    1996-01-01

    It is shown that most recent results of E710 and UA4/2 collaboration for the total cross section and ρ together with earlier measurements give good agreement with measurements for the differential cross section at 546 and 1800 GeV within the framework of Generalised Chou-Yang model. These results are also compared with the predictions of other models. (author)

  7. Applications of soft computing in time series forecasting simulation and modeling techniques

    CERN Document Server

    Singh, Pritpal

    2016-01-01

    This book reports on an in-depth study of fuzzy time series (FTS) modeling. It reviews and summarizes previous research work in FTS modeling and also provides a brief introduction to other soft-computing techniques, such as artificial neural networks (ANNs), rough sets (RS) and evolutionary computing (EC), focusing on how these techniques can be integrated into different phases of the FTS modeling approach. In particular, the book describes novel methods resulting from the hybridization of FTS modeling approaches with neural networks and particle swarm optimization. It also demonstrates how a new ANN-based model can be successfully applied in the context of predicting Indian summer monsoon rainfall. Thanks to its easy-to-read style and the clear explanations of the models, the book can be used as a concise yet comprehensive reference guide to fuzzy time series modeling, and will be valuable not only for graduate students, but also for researchers and professionals working for academic, business and governmen...

  8. Modelling tick abundance using machine learning techniques and satellite imagery

    DEFF Research Database (Denmark)

    Kjær, Lene Jung; Korslund, L.; Kjelland, V.

    satellite images to run Boosted Regression Tree machine learning algorithms to predict overall distribution (presence/absence of ticks) and relative tick abundance of nymphs and larvae in southern Scandinavia. For nymphs, the predicted abundance had a positive correlation with observed abundance...... the predicted distribution of larvae was mostly even throughout Denmark, it was primarily around the coastlines in Norway and Sweden. Abundance was fairly low overall except in some fragmented patches corresponding to forested habitats in the region. Machine learning techniques allow us to predict for larger...... the collected ticks for pathogens and using the same machine learning techniques to develop prevalence maps of the ScandTick region....

  9. Parallel-scanning tomosynthesis using a slot scanning technique: fixed-focus reconstruction and the resulting image quality.

    Science.gov (United States)

    Shibata, Koichi; Notohara, Daisuke; Sakai, Takihito

    2014-11-01

    Parallel-scanning tomosynthesis (PS-TS) is a novel technique that fuses the slot scanning technique and the conventional tomosynthesis (TS) technique. This approach allows one to obtain long-view tomosynthesis images in addition to normally sized tomosynthesis images, even when using a system that has no linear tomographic scanning function. The reconstruction technique and an evaluation of the resulting image quality for PS-TS are described in this paper. The PS-TS image-reconstruction technique consists of several steps (1) the projection images are divided into strips, (2) the strips are stitched together to construct images corresponding to the reconstruction plane, (3) the stitched images are filtered, and (4) the filtered stitched images are back-projected. In the case of PS-TS using the fixed-focus reconstruction method (PS-TS-F), one set of stitched images is used for the reconstruction planes at all heights, thus avoiding the necessity of repeating steps (1)-(3). A physical evaluation of the image quality of PS-TS-F compared with that of the conventional linear TS was performed using a R/F table (Sonialvision safire, Shimadzu Corp., Kyoto, Japan). The tomographic plane with the best theoretical spatial resolution (the in-focus plane, IFP) was set at a height of 100 mm from the table top by adjusting the reconstruction program. First, the spatial frequency response was evaluated at heights of -100, -50, 0, 50, 100, and 150 mm from the IFP using the edge of a 0.3-mm-thick copper plate. Second, the spatial resolution at each height was visually evaluated using an x-ray test pattern (Model No. 38, PTW Freiburg, Germany). Third, the slice sensitivity at each height was evaluated via the wire method using a 0.1-mm-diameter tungsten wire. Phantom studies using a knee phantom and a whole-body phantom were also performed. The spatial frequency response of PS-TS-F yielded the best results at the IFP and degraded slightly as the distance from the IFP increased. A

  10. Agricultural soils decontamination techniques: methods and results of tests realized near Chernobyl

    International Nuclear Information System (INIS)

    Maubert, H.; Jouve, A.; Mary, N.

    1992-01-01

    After a major nuclear accident, decontamination of agricultural soils would be necessary in order to reclaim the land. Specific techniques were studied in the framework of the European program for Rehabilitation of Soils and Surfaces after an Accident (RESSAC). Different ways to remove the top layer of soils are described, and especially the use of Decontaminating Vegetal Network (D.V.N.) combined with spraying of organic polymers. Real scale tests in the 30 km zone around the Chernobyl nuclear power plant showed that it is possible to achieve an excellent decontamination of agricultural fields (decontamination factor greater than 95%. (author)

  11. Identifying and quantifying energy savings on fired plant using low cost modelling techniques

    International Nuclear Information System (INIS)

    Tucker, Robert; Ward, John

    2012-01-01

    Research highlights: → Furnace models based on the zone method for radiation calculation are described. → Validated steady-state and transient models have been developed. → We show how these simple models can identify the best options for saving energy. → High emissivity coatings predicted to give performance enhancement on a fired heater. → Optimal heat recovery strategies on a steel reheating furnace are predicted. -- Abstract: Combustion in fired heaters, boilers and furnaces often accounts for the major energy consumption on industrial processes. Small improvements in efficiency can result in large reductions in energy consumption, CO 2 emissions, and operating costs. This paper will describe some useful low cost modelling techniques based on the zone method to help identify energy saving opportunities on high temperature fuel-fired process plant. The zone method has for many decades, been successfully applied to small batch furnaces through to large steel-reheating furnaces, glass tanks, boilers and fired heaters on petrochemical plant. Zone models can simulate both steady-state furnace operation and more complex transient operation typical of a production environment. These models can be used to predict thermal efficiency and performance, and more importantly, to assist in identifying and predicting energy saving opportunities from such measures as: ·Improving air/fuel ratio and temperature controls. ·Improved insulation. ·Use of oxygen or oxygen enrichment. ·Air preheating via flue gas heat recovery. ·Modification to furnace geometry and hearth loading. There is also increasing interest in the application of refractory coatings for increasing surface radiation in fired plant. All of the techniques can yield savings ranging from a few percent upwards and can deliver rapid financial payback, but their evaluation often requires robust and reliable models in order to increase confidence in making financial investment decisions. This paper gives

  12. Application of integrated modeling technique for data services ...

    African Journals Online (AJOL)

    This paper, therefore, describes the application of the integrated simulation technique for deriving the optimum resources required for data services in an asynchronous transfer mode (ATM) based private wide area network (WAN) to guarantee specific QoS requirement. The simulation tool drastically cuts the simulation ...

  13. Prescribed wind shear modelling with the actuator line technique

    DEFF Research Database (Denmark)

    Mikkelsen, Robert Flemming; Sørensen, Jens Nørkær; Troldborg, Niels

    2007-01-01

    A method for prescribing arbitrary steady atmospheric wind shear profiles combined with CFD is presented. The method is furthermore combined with the actuator line technique governing the aerodynamic loads on a wind turbine. Computation are carried out on a wind turbine exposed to a representative...

  14. A simple novel technique [PUIT] for closure of urethrocutaneous fistula after hypospadias repair: Preliminary results

    Directory of Open Access Journals (Sweden)

    Awad M

    2005-01-01

    Full Text Available Urethrocutaneous fistula is a common complication of urethroplasty for severe hypospadias, even when a microsurgical technique is applied, the closure of the fistula is a challenging problem. We present a simple surgical procedure, posterior urethral incision technique [PUIT] to close the fistula in our department. Between February 2001 and December 2004 we prospectively evaluated 32 patients, 26 patients with initial hypospadias fistulas and 6 with recurrent fistulas who underwent closure of urethrocutaneous fistula after hypospadias repair. The mean age of patients was 5 years, the operation consisted of trimming the fistula edge after mobilization of the skin all-around then a midline posterior urethral incision was done 2 mm above and 2 mm below the fistula opening then re-approximation of the urethral edges using 6/0 vicryl sutures with loop magnification. The timing of fistula repair was between 6 and 13 months after it was formed, all of these were effectively closed except three cases with stricture and fistula. Of these, two were completely relieved after repeated urethral dilatation, three times a week for 2 weeks. The third failed case will need another sitting after 6 months. The posterior midline urethral incision gives a good opportunity for repair without tension with a good cosmetic outcome. This may be done under local anesthesia in adults. The procedure is considered simple rapid and easy to be done for variable fistulas types whatever of its site and the age.

  15. Introduction results of radiosurgery technique in cervical pathology consultation. Analysis of five years 2004 – 2009.

    Directory of Open Access Journals (Sweden)

    Rafael E. Pérez Castro

    2011-06-01

    Full Text Available AA cross sectional study and retrospective was performed in patients having cervical intraepithelial neoplasia (CIN, mainly in high grade lesions (CIN II, CIN III and C. In situ, which were treated with radiosurgery technique in the University General Hospital “Camilo Cienfuegos” Sancti Spiritus during the period may 2004 – may 2009 with the objective to evaluate the radiosurgery`s behaviour in the period mentioned before. The studied group was conformed by 550 patients having high grade lesions and low grade persistent lesions (NIC I with previous biopsy, a smaller group of 24 cases was formed by benign pathologies tributary of this procedure. High grade lesions were of major indications (73.1%. 69 cases were false negative (13.3%; since the second decade of life were presented high and low grade lesions of cervical pathology, a good correlation punch – cone byopsy was checked; edges of the surgical section behave properly, lower than what it is established in the international standard (6.7. The procedure had a great economic and social impact, because it is an ambulatory technique with few difficulties, low cost, and a fast integration patient – normal work.

  16. Results from the IAEA benchmark of spallation models

    International Nuclear Information System (INIS)

    Leray, S.; David, J.C.; Khandaker, M.; Mank, G.; Mengoni, A.; Otsuka, N.; Filges, D.; Gallmeier, F.; Konobeyev, A.; Michel, R.

    2011-01-01

    Spallation reactions play an important role in a wide domain of applications. In the simulation codes used in this field, the nuclear interaction cross-sections and characteristics are computed by spallation models. The International Atomic Energy Agency (IAEA) has recently organised a benchmark of the spallation models used or that could be used in the future into high-energy transport codes. The objectives were, first, to assess the prediction capabilities of the different spallation models for the different mass and energy regions and the different exit channels and, second, to understand the reason for the success or deficiency of the models. Results of the benchmark concerning both the analysis of the prediction capabilities of the models and the first conclusions on the physics of spallation models are presented. (authors)

  17. On a Numerical and Graphical Technique for Evaluating some Models Involving Rational Expectations

    DEFF Research Database (Denmark)

    Johansen, Søren; Swensen, Anders Rygh

    Campbell and Shiller (1987) proposed a graphical technique for the present value model which consists of plotting the spread and theoretical spread as calculated from the cointegrated vector autoregressive model. We extend these techniques to a number of rational expectation models and give...

  18. On a numerical and graphical technique for evaluating some models involving rational expectations

    DEFF Research Database (Denmark)

    Johansen, Søren; Swensen, Anders Rygh

    Campbell and Shiller (1987) proposed a graphical technique for the present value model which consists of plotting the spread and theoretical spread as calculated from the cointegrated vector autoregressive model. We extend these techniques to a number of rational expectation models and give...

  19. A Dynamic Operation Permission Technique Based on an MFM Model and Numerical Simulation

    International Nuclear Information System (INIS)

    Akio, Gofuku; Masahiro, Yonemura

    2011-01-01

    It is important to support operator activities to an abnormal plant situation where many counter actions are taken in relatively short time. The authors proposed a technique called dynamic operation permission to decrease human errors without eliminating creative idea of operators to cope with an abnormal plant situation by checking if the counter action taken is consistent with emergency operation procedure. If the counter action is inconsistent, a dynamic operation permission system warns it to operators. It also explains how and why the counter action is inconsistent and what influence will appear on the future plant behavior by a qualitative influence inference technique based on a model by the Mf (Multilevel Flow Modeling). However, the previous dynamic operation permission is not able to explain quantitative effects on plant future behavior. Moreover, many possible influence paths are derived because a qualitative reasoning does not give a solution when positive and negative influences are propagated to the same node. This study extends the dynamic operation permission by combining the qualitative reasoning and the numerical simulation technique. The qualitative reasoning based on an Mf model of plant derives all possible influence propagation paths. Then, a numerical simulation gives a prediction of plant future behavior in the case of taking a counter action. The influence propagation that does not coincide with the simulation results is excluded from possible influence paths. The extended technique is implemented in a dynamic operation permission system for an oil refinery plant. An MFM model and a static numerical simulator are developed. The results of dynamic operation permission for some abnormal plant situations show the improvement of the accuracy of dynamic operation permission and the quality of explanation for the effects of the counter action taken

  20. Modelling, analysis and validation of microwave techniques for the characterisation of metallic nanoparticles

    Science.gov (United States)

    Sulaimalebbe, Aslam

    High Frequency Structure Simulator (HFSS), followed by the electrical characterisation of synthesised Pt NP films using the novel miniature fabricated OCP technique. The results obtained from this technique provided the inspiration to synthesise and evaluate the microwave properties of Au NPs. The findings from this technique provided the motivation to characterise both the Pt and Au NP films using the DR technique. Unlike the OCP technique, the DR method is highly sensitive but the achievable measurement accuracy is limited since this technique does not have broadband frequency capability like the OCP method. The results obtained from the DR technique show a good agreement with the theoretical prediction. In the last phase of this research, a further validation of the aperture admittance models on different types OCP (i.e. RG-405 and RG-402 cables and SMA connector) have been carried out on the developed 3D full wave models using HFSS software, followed by the development of universal models for the aforementioned OCPs based on the same 3D full wave models.

  1. The application of neural networks with artificial intelligence technique in the modeling of industrial processes

    International Nuclear Information System (INIS)

    Saini, K. K.; Saini, Sanju

    2008-01-01

    Neural networks are a relatively new artificial intelligence technique that emulates the behavior of biological neural systems in digital software or hardware. These networks can 'learn', automatically, complex relationships among data. This feature makes the technique very useful in modeling processes for which mathematical modeling is difficult or impossible. The work described here outlines some examples of the application of neural networks with artificial intelligence technique in the modeling of industrial processes.

  2. Trimming a hazard logic tree with a new model-order-reduction technique

    Science.gov (United States)

    Porter, Keith; Field, Edward; Milner, Kevin R

    2017-01-01

    The size of the logic tree within the Uniform California Earthquake Rupture Forecast Version 3, Time-Dependent (UCERF3-TD) model can challenge risk analyses of large portfolios. An insurer or catastrophe risk modeler concerned with losses to a California portfolio might have to evaluate a portfolio 57,600 times to estimate risk in light of the hazard possibility space. Which branches of the logic tree matter most, and which can one ignore? We employed two model-order-reduction techniques to simplify the model. We sought a subset of parameters that must vary, and the specific fixed values for the remaining parameters, to produce approximately the same loss distribution as the original model. The techniques are (1) a tornado-diagram approach we employed previously for UCERF2, and (2) an apparently novel probabilistic sensitivity approach that seems better suited to functions of nominal random variables. The new approach produces a reduced-order model with only 60 of the original 57,600 leaves. One can use the results to reduce computational effort in loss analyses by orders of magnitude.

  3. First results from the International Urban Energy Balance Model Comparison: Model Complexity

    Science.gov (United States)

    Blackett, M.; Grimmond, S.; Best, M.

    2009-04-01

    offline to ensure no feedback to larger scale conditions within the modelling domain. Initially, participants were issued with just forcing data from an unknown urban site (termed "Alpha"); in subsequent stages, further details of the site were provided. Results from each stage, for each participating model, were then compared using a variety of statistical and graphical techniques. * The EGU2009-5713 Team: C.S.B. Grimmond1, M. Blackett1, M. Best2 and J. Barlow3and J.-J. Baik4, S. Belcher3, S. Bohnenstengel3, I. Calmet5, F. Chen6, A. Dandou7, K. Fortuniak8, M. Gouvea1, R. Hamdi9, M. Hendry2, H. Kondo10, S. Krayenhoff11, S. H. Lee4, T. Loridan1, A. Martilli12, S. Miao13, K. Oleson6, G. Pigeon14, A. Porson2,3, F. Salamanca12, L. Shashua-Bar15, G.-J. Steeneveld16, M. Tombrou7, J. Voogt17, N. Zhang18. 1King's College London, UK, 2UK Met Office, UK, 3University of Reading, UK, 4Seoul National University, Korea, 5Ecole Centrale de Nantes, France, 6National Center for Atmospheric Research, USA, 7University of Athens, Greece, 8University of Ł ódź , Poland, 9Royal Meteorological Institute, Belgium, 10National Institute of Advanced Industrial Science and Technology, Japan, 11University of British Columbia, Canada, 12CIEMAT, Spain, 13IUM, CMA, China, 14Meteo France, France, 15Ben Gurion University, Israel, 16Wageningen University, Netherlands, 17University of Western Ontario, Canada, 18Nanjing University, China.

  4. Three Proposed Compendia for Genesis Solar Wind Samples: Science Results, Collector Materials Characterization and Cleaning Techniques

    Science.gov (United States)

    Allton, J. H.; Calaway, M. J.; Nyquist, L. E.; Jurewicz, A. J. G.; Burnett, D. S.

    2018-01-01

    Final Paper and not the abstract is attached. Introduction: Planetary material and cosmochemistry research using Genesis solar wind samples (including the development and implementation of cleaning and analytical techniques) has matured sufficiently that compilations on several topics, if made publically accessible, would be beneficial for researchers and reviewers. We propose here three compendia based on content, organization and source of documents (e.g. published peer-reviewed, published, internal memos, archives). For planning purposes, suggestions are solicited from potential users of Genesis solar wind samples for the type of science content and/or organizational style that would be most useful to them. These compendia are proposed as living documents, periodically updated. Similar to the existing compendia described below, the curation compendia are like library or archival finding aids, they are guides to published or archival documents and should not be cited as primary sources.

  5. Dynamic cholangio-cysto scintigraphy with sup(99m)Tc HIDA. Technique - Interpretation of results

    International Nuclear Information System (INIS)

    Queant, D.G.C.

    1978-10-01

    Amongst all the methods used to explore the bile function of the liver, isotopic cholangio-cysto scintigraphy should be ideally placed because of its harmlessness and ease of application and the importance of the information supplied. By this technique the bile function may be explored in its various aspects. Functional kinetics: - uptake and excretion by the hepatocytes, - storage and motivity (spontaneous or activated), - spontaneous vesicular rhythm. Morphological: - size and permeability of the bile ducts. The purpose of this study is to define the practical details involved in sup(99mTc)-HIDA cholangio-cysto scintigraphy and to estimate its reliability, advantages and limits. It covers the first 20 patients subjected to this examination in the biophysics service of the Lyon-Sud Faculty of Medicine [fr

  6. The effect of bathymetric filtering on nearshore process model results

    Science.gov (United States)

    Plant, N.G.; Edwards, K.L.; Kaihatu, J.M.; Veeramony, J.; Hsu, L.; Holland, K.T.

    2009-01-01

    Nearshore wave and flow model results are shown to exhibit a strong sensitivity to the resolution of the input bathymetry. In this analysis, bathymetric resolution was varied by applying smoothing filters to high-resolution survey data to produce a number of bathymetric grid surfaces. We demonstrate that the sensitivity of model-predicted wave height and flow to variations in bathymetric resolution had different characteristics. Wave height predictions were most sensitive to resolution of cross-shore variability associated with the structure of nearshore sandbars. Flow predictions were most sensitive to the resolution of intermediate scale alongshore variability associated with the prominent sandbar rhythmicity. Flow sensitivity increased in cases where a sandbar was closer to shore and shallower. Perhaps the most surprising implication of these results is that the interpolation and smoothing of bathymetric data could be optimized differently for the wave and flow models. We show that errors between observed and modeled flow and wave heights are well predicted by comparing model simulation results using progressively filtered bathymetry to results from the highest resolution simulation. The damage done by over smoothing or inadequate sampling can therefore be estimated using model simulations. We conclude that the ability to quantify prediction errors will be useful for supporting future data assimilation efforts that require this information.

  7. An eigenexpansion technique for modelling plasma start-up

    International Nuclear Information System (INIS)

    Pillsbury, R.D.

    1989-01-01

    An algorithm has been developed and implemented in a computer program that allows the estimation of PF coil voltages required to start-up an axisymmetric plasma in a tokamak in the presence of eddy currents in toroidally continuous conducting structures. The algorithm makes use of an eigen-expansion technique to solve the lumped parameter circuit loop voltage equations associated with the PF coils and passive (conducting) structures. An example of start-up for CIT (Compact Ignition Tokamak) is included

  8. Wave propagation in fluids models and numerical techniques

    CERN Document Server

    Guinot, Vincent

    2012-01-01

    This second edition with four additional chapters presents the physical principles and solution techniques for transient propagation in fluid mechanics and hydraulics. The application domains vary including contaminant transport with or without sorption, the motion of immiscible hydrocarbons in aquifers, pipe transients, open channel and shallow water flow, and compressible gas dynamics. The mathematical formulation is covered from the angle of conservation laws, with an emphasis on multidimensional problems and discontinuous flows, such as steep fronts and shock waves. Finite

  9. A vortex model for Darrieus turbine using finite element techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ponta, Fernando L. [Universidad de Buenos Aires, Dept. de Electrotecnia, Grupo ISEP, Buenos Aires (Argentina); Jacovkis, Pablo M. [Universidad de Buenos Aires, Dept. de Computacion and Inst. de Calculo, Buenos Aires (Argentina)

    2001-09-01

    Since 1970 several aerodynamic prediction models have been formulated for the Darrieus turbine. We can identify two families of models: stream-tube and vortex. The former needs much less computation time but the latter is more accurate. The purpose of this paper is to show a new option for modelling the aerodynamic behaviour of Darrieus turbines. The idea is to combine a classic free vortex model with a finite element analysis of the flow in the surroundings of the blades. This avoids some of the remaining deficiencies in classic vortex models. The agreement between analysis and experiment when predicting instantaneous blade forces and near wake flow behind the rotor is better than the one obtained in previous models. (Author)

  10. Artificial intelligence techniques for modeling database user behavior

    Science.gov (United States)

    Tanner, Steve; Graves, Sara J.

    1990-01-01

    The design and development of the adaptive modeling system is described. This system models how a user accesses a relational database management system in order to improve its performance by discovering use access patterns. In the current system, these patterns are used to improve the user interface and may be used to speed data retrieval, support query optimization and support a more flexible data representation. The system models both syntactic and semantic information about the user's access and employs both procedural and rule-based logic to manipulate the model.

  11. Evaluation of 3-dimensional superimposition techniques on various skeletal structures of the head using surface models.

    Directory of Open Access Journals (Sweden)

    Nikolaos Gkantidis

    Full Text Available To test the applicability, accuracy, precision, and reproducibility of various 3D superimposition techniques for radiographic data, transformed to triangulated surface data.Five superimposition techniques (3P: three-point registration; AC: anterior cranial base; AC + F: anterior cranial base + foramen magnum; BZ: both zygomatic arches; 1Z: one zygomatic arch were tested using eight pairs of pre-existing CT data (pre- and post-treatment. These were obtained from non-growing orthodontic patients treated with rapid maxillary expansion. All datasets were superimposed by three operators independently, who repeated the whole procedure one month later. Accuracy was assessed by the distance (D between superimposed datasets on three form-stable anatomical areas, located on the anterior cranial base and the foramen magnum. Precision and reproducibility were assessed using the distances between models at four specific landmarks. Non parametric multivariate models and Bland-Altman difference plots were used for analyses.There was no difference among operators or between time points on the accuracy of each superimposition technique (p>0.05. The AC + F technique was the most accurate (D0.05, the detected structural changes differed significantly between different techniques (p<0.05. Bland-Altman difference plots showed that BZ superimposition was comparable to AC, though it presented slightly higher random error.Superimposition of 3D datasets using surface models created from voxel data can provide accurate, precise, and reproducible results, offering also high efficiency and increased post-processing capabilities. In the present study population, the BZ superimposition was comparable to AC, with the added advantage of being applicable to scans with a smaller field of view.

  12. Evaluation of 3-dimensional superimposition techniques on various skeletal structures of the head using surface models.

    Science.gov (United States)

    Gkantidis, Nikolaos; Schauseil, Michael; Pazera, Pawel; Zorkun, Berna; Katsaros, Christos; Ludwig, Björn

    2015-01-01

    To test the applicability, accuracy, precision, and reproducibility of various 3D superimposition techniques for radiographic data, transformed to triangulated surface data. Five superimposition techniques (3P: three-point registration; AC: anterior cranial base; AC + F: anterior cranial base + foramen magnum; BZ: both zygomatic arches; 1Z: one zygomatic arch) were tested using eight pairs of pre-existing CT data (pre- and post-treatment). These were obtained from non-growing orthodontic patients treated with rapid maxillary expansion. All datasets were superimposed by three operators independently, who repeated the whole procedure one month later. Accuracy was assessed by the distance (D) between superimposed datasets on three form-stable anatomical areas, located on the anterior cranial base and the foramen magnum. Precision and reproducibility were assessed using the distances between models at four specific landmarks. Non parametric multivariate models and Bland-Altman difference plots were used for analyses. There was no difference among operators or between time points on the accuracy of each superimposition technique (p>0.05). The AC + F technique was the most accurate (D0.05), the detected structural changes differed significantly between different techniques (p<0.05). Bland-Altman difference plots showed that BZ superimposition was comparable to AC, though it presented slightly higher random error. Superimposition of 3D datasets using surface models created from voxel data can provide accurate, precise, and reproducible results, offering also high efficiency and increased post-processing capabilities. In the present study population, the BZ superimposition was comparable to AC, with the added advantage of being applicable to scans with a smaller field of view.

  13. Circulation in the Gulf of Trieste: measurements and model results

    International Nuclear Information System (INIS)

    Bogunovici, B.; Malacic, V.

    2008-01-01

    The study presents seasonal variability of currents in the southern part of the Gulf of Trieste. A time series analysis of currents and wind stress for the period 2003-2006, which were measured by the coastal oceanographic buoy, was conducted. A comparison between these data and results obtained from a numerical model of circulation in the Gulf was performed to validate model results. Three different approaches were applied to the wind data to determine the wind stress. Similarities were found between Kondo and Smith approaches while the method of Vera shows differences which were particularly noticeable for lower (= 1 m/s) and higher wind speeds (= 15 m/s). Mean currents in the surface layer are generally outflow currents from the Gulf due to wind forcing (bora). However in all other depth layers inflow currents are dominant. With the principal component analysis (Pca) major and minor axes were determined for all seasons. The major axis of maximum variance in years between 2003 and 2006 is prevailing in Ne-Sw direction, which is parallel to the coastline. Comparison of observation and model results is showing that currents are similar (in direction) for the surface and bottom layers but are significantly different for the middle layer (5-13 m). At a depth between 14-21 m velocities are comparable in direction as well as in magnitude even though model values are higher. Higher values of modelled currents at the surface and near the bottom are explained by higher values of wind stress that were used in the model as driving input with respect to the stress calculated from the measured winds. Larger values of modelled currents near the bottom are related to the larger inflow that needs to compensate for the larger modelled outflow at the surface. However, inspection of the vertical structure of temperature, salinity and density shows that the model is reproducing a weaker density gradient which enables the penetration of the outflow surface currents to larger depths.

  14. Development Model of Basic Technique Skills Training Shot-Put Obrien Style Based Biomechanics Review

    Directory of Open Access Journals (Sweden)

    danang rohmat hidayanto

    2018-03-01

    Full Text Available The background of this research is the unavailability of learning model of basic technique technique of O'Brien style force that integrated in skill program based on biomechanics study which is used as a reference to build the basic technique skill of the O'Brien style force among students. The purpose of this study is to develop a model of basic-style technique of rejecting the O'Brien-style shot put based on biomechanical studies for beginner levels, including basic prefix technique, glide, final stage, repulsion, further motion and repulsion performance of O'Brien style, all of which arranged in a medium that is easily accessible whenever, by anyone and anywhere, especially in SMK Negeri 1 Kalijambe Sragen . The research method used is "Reasearch and Developement" approach. "Preliminary studies show that 43.0% of respondents considered that the O'Brien style was very important to be developed with a model of skill-based exercise based on biomechanics, as many as 40.0% ressponden stated that it is important to be developed with biomechanics based learning media. Therefore, it is deemed necessary to develop the learning media of the O'Brien style-based training skills based on biomechanical studies. Development of media starts from the design of the storyboard and script form that will be used as media. The design of this model is called the draft model. Draft models that have been prepared are reviewed by the multimedia expert and the O'Brien style expert to get the product's validity. A total of 78.24% of experts declare a viable product with some input. In small groups with n = 6, earned value 72.2% was obtained or valid enough to be tested in large groups. In the large group test with n = 12,values obtained 70.83% or quite feasible to be tested in the field. In the field test, experimental group was prepared with treatment according to media and control group with free treatment. From result of counting of significance test can be

  15. Multiparous Ewe as a Model for Teaching Vaginal Hysterectomy Techniques.

    Science.gov (United States)

    Kerbage, Yohan; Cosson, Michel; Hubert, Thomas; Giraudet, Géraldine

    2017-12-01

    Despite being linked to improving patient outcomes and limiting costs, the use of vaginal hysterectomy is on the wane. Although a combination of reasons might explain this trend, one cause is a lack of practical training. An appropriate teaching model must therefore be devised. Currently, only low-fidelity simulators exist. Ewes provide an appropriate model for pelvic anatomy and are well-suited for testing vaginal mesh properties. This article sets out a vaginal hysterectomy procedure for use as an education and training model. A multiparous ewe was the model. Surgery was performed under general anesthesia. The ewe was in a lithotomy position resembling that assumed by women on the operating table. Two vaginal hysterectomies were performed on two ewes, following every step precisely as if the model were human. Each surgical step of vaginal hysterectomy performed on the ewe and on a woman were compared side by side. We identified that all surgical steps were particularly similar. The main limitations of this model are costs ($500/procedure), logistic problems (housing large animals), and public opposition to animal training models. The ewe appears to be an appropriate model for teaching and training of vaginal hysterectomy.

  16. Melt coolability modeling and comparison to MACE test results

    International Nuclear Information System (INIS)

    Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.

    1992-01-01

    An important question in the assessment of severe accidents in light water nuclear reactors is the ability of water to quench a molten corium-concrete interaction and thereby terminate the accident progression. As part of the Melt Attack and Coolability Experiment (MACE) Program, phenomenological models of the corium quenching process are under development. The modeling approach considers both bulk cooldown and crust-limited heat transfer regimes, as well as criteria for the pool thermal hydraulic conditions which separate the two regimes. The model is then compared with results of the MACE experiments

  17. Results and Error Estimates from GRACE Forward Modeling over Greenland, Canada, and Alaska

    Science.gov (United States)

    Bonin, J. A.; Chambers, D. P.

    2012-12-01

    Forward modeling using a weighted least squares technique allows GRACE information to be projected onto a pre-determined collection of local basins. This decreases the impact of spatial leakage, allowing estimates of mass change to be better localized. The technique is especially valuable where models of current-day mass change are poor, such as over Greenland and Antarctica. However, the accuracy of the forward model technique has not been determined, nor is it known how the distribution of the local basins affects the results. We use a "truth" model composed of hydrology and ice-melt slopes as an example case, to estimate the uncertainties of this forward modeling method and expose those design parameters which may result in an incorrect high-resolution mass distribution. We then apply these optimal parameters in a forward model estimate created from RL05 GRACE data. We compare the resulting mass slopes with the expected systematic errors from the simulation, as well as GIA and basic trend-fitting uncertainties. We also consider whether specific regions (such as Ellesmere Island and Baffin Island) can be estimated reliably using our optimal basin layout.

  18. Double contrast barium enema: technique, indications, results and limitations of a conventional imaging methodology in the MDCT virtual endoscopy era.

    Science.gov (United States)

    Rollandi, Gian Andrea; Biscaldi, Ennio; DeCicco, Enzo

    2007-03-01

    The double contrast barium enema of the colon continues to be a diffused conventional radiological technique and allows for the diagnosis of neoplastic and inflammatory pathology. After the '70s, a massive initiative is undertaken to simplify, perfect and encode the method of the double contrast barium enema: Altaras from Germany, Miller from USA and Cittadini from Italy are responsible for the perfection of this technique in the last 30 years. The tailored patient preparation, a perfect technique of execution and a precise radiological documentation are essentials steps to obtain a reliable examination. The main limit of double contrast enema is that it considers the pathology only from the mucosal surface. In neoplastic pathology evaluation the main limit is the "T" parameter staging, but more limited are the "N" and "M" parameters evaluation. Today the double contrast technique continues to be a refined, sensitive and specific diagnostic method, moreover, diagnostic results cannot compete with the new CT multislice techniques (CT-enteroclysis and virtual colonoscopy) which can examine both the lumen and the wall of the colon. The double contrast is a cheap and simple examination but in the next future is predictably a progressive substitution of conventional radiology from new multislice techniques, because the cross sectional imaging is more frequently able to detect causes of the symptoms whether resulting both from colonic or non colonic origin.

  19. Double contrast barium enema: Technique, indications, results and limitations of a conventional imaging methodology in the MDCT virtual endoscopy era

    International Nuclear Information System (INIS)

    Rollandi, Gian Andrea; Biscaldi, Ennio; DeCicco, Enzo

    2007-01-01

    The double contrast barium enema of the colon continues to be a diffused conventional radiological technique and allows for the diagnosis of neoplastic and inflammatory pathology. After the '70s, a massive initiative is undertaken to simplify, perfect and encode the method of the double contrast barium enema: Altaras from Germany, Miller from USA and Cittadini from Italy are responsible for the perfection of this technique in the last 30 years. The tailored patient preparation, a perfect technique of execution and a precise radiological documentation are essentials steps to obtain a reliable examination. The main limit of double contrast enema is that it considers the pathology only from the mucosal surface. In neoplastic pathology evaluation the main limit is the 'T' parameter staging, but more limited are the 'N' and 'M' parameters evaluation. Today the double contrast technique continues to be a refined, sensitive and specific diagnostic method, moreover, diagnostic results cannot compete with the new CT multislice techniques (CT-enteroclysis and virtual colonoscopy) which can examine both the lumen and the wall of the colon. The double contrast is a cheap and simple examination but in the next future is predictably a progressive substitution of conventional radiology from new multislice techniques, because the cross sectional imaging is more frequently able to detect causes of the symptoms whether resulting both from colonic or non colonic origin

  20. Assessing sequential data assimilation techniques for integrating GRACE data into a hydrological model

    KAUST Repository

    Khaki, M.

    2017-07-06

    The time-variable terrestrial water storage (TWS) products from the Gravity Recovery And Climate Experiment (GRACE) have been increasingly used in recent years to improve the simulation of hydrological models by applying data assimilation techniques. In this study, for the first time, we assess the performance of the most popular data assimilation sequential techniques for integrating GRACE TWS into the World-Wide Water Resources Assessment (W3RA) model. We implement and test stochastic and deterministic ensemble-based Kalman filters (EnKF), as well as Particle filters (PF) using two different resampling approaches of Multinomial Resampling and Systematic Resampling. These choices provide various opportunities for weighting observations and model simulations during the assimilation and also accounting for error distributions. Particularly, the deterministic EnKF is tested to avoid perturbing observations before assimilation (that is the case in an ordinary EnKF). Gaussian-based random updates in the EnKF approaches likely do not fully represent the statistical properties of the model simulations and TWS observations. Therefore, the fully non-Gaussian PF is also applied to estimate more realistic updates. Monthly GRACE TWS are assimilated into W3RA covering the entire Australia. To evaluate the filters performances and analyze their impact on model simulations, their estimates are validated by independent in-situ measurements. Our results indicate that all implemented filters improve the estimation of water storage simulations of W3RA. The best results are obtained using two versions of deterministic EnKF, i.e. the Square Root Analysis (SQRA) scheme and the Ensemble Square Root Filter (EnSRF), respectively improving the model groundwater estimations errors by 34% and 31% compared to a model run without assimilation. Applying the PF along with Systematic Resampling successfully decreases the model estimation error by 23%.

  1. Korean round-robin result for new international program to assess the reliability of emerging nondestructive techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Cho; Kim, Jin Gyum; Kang, Sung Sik; Jhung, Myung Jo [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2017-04-15

    The Korea Institute of Nuclear Safety, as a representative organization of Korea, in February 2012 participated in an international Program to Assess the Reliability of Emerging Nondestructive Techniques initiated by the U.S. Nuclear Regulatory Commission. The goal of the Program to Assess the Reliability of Emerging Nondestructive Techniques is to investigate the performance of emerging and prospective novel nondestructive techniques to find flaws in nickel-alloy welds and base materials. In this article, Korean round-robin test results were evaluated with respect to the test blocks and various nondestructive examination techniques. The test blocks were prepared to simulate large-bore dissimilar metal welds, small-bore dissimilar metal welds, and bottom-mounted instrumentation penetration welds in nuclear power plants. Also, lessons learned from the Korean round-robin test were summarized and discussed.

  2. Optic neuropathy in thyroid eye disease: results of the balanced decompression technique.

    Science.gov (United States)

    Baril, Catherine; Pouliot, Denis; Molgat, Yvonne

    2014-04-01

    To determine the efficacy of combined endoscopic medial and external lateral orbital decompression for the treatment of compressive optic neuropathy (CON) in thyroid eye disease (TED). A retrospective review of all patients undergoing combined surgical orbital decompression for CON between 2000 and 2010 was conducted. Fifty-nine eyes of 34 patients undergoing combined surgical orbital decompression for CON. Clinical outcome measures included visual acuity, Hardy-Rand-Rittler (HRR) colour plate testing, relative afferent pupillary defect, intraocular pressure measurement, and Hertel exophthalmometry. A CON score was calculated preoperatively and postoperatively based on the visual acuity and the missed HRR plates. A higher CON score correlates with more severe visual dysfunction. All patients had improvement of their optic neuropathy after surgical decompression. CON score was calculated for 54 eyes and decreased significantly from a mean of 13.2 ± 10.35 preoperatively to a mean of 8.51 ± 10.24 postoperatively (p < 0.0001). Optic neuropathy was completely resolved in 93.22% (55/59 eyes). Eighteen of 34 patients (52.94%) experienced development of new-onset postoperative strabismus that required subsequent surgical intervention. Endoscopic medial combined with external lateral orbital decompression is an effective technique for the treatment of TED-associated CON. © 2013 Canadian Ophthalmological Society Published by Canadian Ophthalmological Society All rights reserved.

  3. Results of a protocol of transfusion threshold and surgical technique on transfusion requirements in burn patients.

    Science.gov (United States)

    O'Mara, Michael S; Hayetian, Fernando; Slater, Harvey; Goldfarb, I William; Tolchin, Eric; Caushaj, Philip F

    2005-08-01

    Blood loss and high rates of transfusion in burn centers remains an area of ongoing concern. Blood use brings the risk of infection, adverse reaction, and immunosuppression. A protocol to reduce blood loss and blood use was implemented. Analysis included 3-year periods before and after institution of the protocol. All patients were transfused for a hemoglobin below 8.0 gm/dL. Operations per admission did not change during the two time periods (0.78 in each). Overall units transfused per operation decreased from 1.56+/-0.06 to 1.25+/-0.14 units after instituting the protocol (pburns of less than 20% surface area, declining from 386 to 46 units after protocol institution, from 0.37 to 0.04 units per admission, and from 0.79 to 0.08 units per operation in this group of smallest burns. There was no change noted in the larger burns. This study suggests that a defined protocol of hemostasis, technique, and transfusion trigger should be implemented in the process of burn excision and grafting. This will help especially those patients with the smallest burns, essentially eliminating transfusion need in that group.

  4. Ultra-mini PNL (UMP): Material, indications, technique, advantages and results.

    Science.gov (United States)

    Desai, Janak D

    2017-01-01

    Stone disease has afflicted mankind since centuries; records from ancient civilisations of India and Egypt have shown stones in human bodies. The scientific mind of humans has always made smart endeavours to remove the kidney stones. From large instruments made like the beaks of different animals and birds in 600 BC (Indian civilisation) to extremely sophisticated and miniaturised endoscopic intruments of today the human race has travelled a long way. The theme has always been to remove the stones with minimal morbidity and mortality and with minimum pain to the patient. The article takes you through the journey of instruments used in 600 BC until today. The story of instrumentation is a symbiosis of the medical minds along with engineering advances. The story of miniaturisation could not have moved further without the development of lasers, fiberoptics and sophisticated cameras. As the field stands today, we remove more complex stones by larger endoscopic intervention and smaller stones by miniaturised instruments. The article discusses all the merits and shortcomings of various techniques: from open surgery to standard PCNL to Mini PCNL to Ultra- Mini PCNL to Micro-PCNL.

  5. Perineal colostomy: an alternative to avoid permanent abdominal colostomy: operative technique, results and reflection.

    Science.gov (United States)

    da Silva, Alcino Lázaro; Hayck, Johnny; Deoti, Beatriz

    2014-01-01

    The most common injury to indicate definitive stoma is rectal cancer. Despite advances in surgical treatment, the abdominoperineal resection is still the most effective operation in radical treatment of malignancies of the distal rectum invading the sphincter and anal canal. Even with all the effort that surgeons have to preserve anal sphincters, abdominoperineal amputation is still indicated, and a definitive abdominal colostomy is necessary. This surgery requires patients to live with a definitive abdominal colostomy, which is a condition that modify body image, is not without morbidity and has great impact on the quality of life. To evaluate the technique of abdominoperineal amputation with perineal colostomy with irrigation as an alternative to permanent abdominal colostomy. Retrospective analysis of medical records of 55 patients underwent abdominoperineal resection of the rectum with perineal colostomy in the period 1989-2010. The mean age was 58 years, 40 % men and 60 % women. In 94.5% of patients the indication for surgery was for cancer of the rectum. In some patients were made three valves, other two valves and in the remaining no valve at all. Complications were: mucosal prolapse, necrosis of the lowered segment and stenosis. The abdominoperineal amputation with perineal colostomy is a good therapeutic option in the armamentarium of the surgical treatment of rectal cancer.

  6. Towards Intelligent Interpretation of Low Strain Pile Integrity Testing Results Using Machine Learning Techniques.

    Science.gov (United States)

    Cui, De-Mi; Yan, Weizhong; Wang, Xiao-Quan; Lu, Lie-Min

    2017-10-25

    Low strain pile integrity testing (LSPIT), due to its simplicity and low cost, is one of the most popular NDE methods used in pile foundation construction. While performing LSPIT in the field is generally quite simple and quick, determining the integrity of the test piles by analyzing and interpreting the test signals (reflectograms) is still a manual process performed by experienced experts only. For foundation construction sites where the number of piles to be tested is large, it may take days before the expert can complete interpreting all of the piles and delivering the integrity assessment report. Techniques that can automate test signal interpretation, thus shortening the LSPIT's turnaround time, are of great business value and are in great need. Motivated by this need, in this paper, we develop a computer-aided reflectogram interpretation (CARI) methodology that can interpret a large number of LSPIT signals quickly and consistently. The methodology, built on advanced signal processing and machine learning technologies, can be used to assist the experts in performing both qualitative and quantitative interpretation of LSPIT signals. Specifically, the methodology can ease experts' interpretation burden by screening all test piles quickly and identifying a small number of suspected piles for experts to perform manual, in-depth interpretation. We demonstrate the methodology's effectiveness using the LSPIT signals collected from a number of real-world pile construction sites. The proposed methodology can potentially enhance LSPIT and make it even more efficient and effective in quality control of deep foundation construction.

  7. Physical startup tests for VVER-1200 of Novovoronezh NPP. Advanced technique and some results

    Energy Technology Data Exchange (ETDEWEB)

    Afanasiev, Dmitry A.; Kraynov, Yury A.; Pinegin, Anatoly A.; Tsyganov, Sergey V. [National Research Centre, Moscow (Russian Federation). Kurchatov Inst.

    2017-09-15

    The intention of the startup physics tests was to confirm design characteristics of the core loading and their compliance with safety analysis preconditions. The program of startup tests for the leading unit is usually composed in such a way that is is possible to study as much neutron-physical characteristics as possible in the safest condition of zero power. State-of-the-art safety analysis is including computer codes that use three dimensional neutron kinetics and thermohydraulics models. For the substantiation of such models, for its validation and verification there is a need in reactor experiments that implementing spatially distributed transients. We based on such statements when composing hot zero power physical startup program for the new VVER-1200 unit of Novovoronezh NPP. Several tests unconventional for VVER were developed for that program. It includes measuring the worth for each of control rod groups and measuring of single rod worth from the inserted groups - test that models rod ejection event in some sense.

  8. Modeling rainfall-runoff process using soft computing techniques

    Science.gov (United States)

    Kisi, Ozgur; Shiri, Jalal; Tombul, Mustafa

    2013-02-01

    Rainfall-runoff process was modeled for a small catchment in Turkey, using 4 years (1987-1991) of measurements of independent variables of rainfall and runoff values. The models used in the study were Artificial Neural Networks (ANNs), Adaptive Neuro-Fuzzy Inference System (ANFIS) and Gene Expression Programming (GEP) which are Artificial Intelligence (AI) approaches. The applied models were trained and tested using various combinations of the independent variables. The goodness of fit for the model was evaluated in terms of the coefficient of determination (R2), root mean square error (RMSE), mean absolute error (MAE), coefficient of efficiency (CE) and scatter index (SI). A comparison was also made between these models and traditional Multi Linear Regression (MLR) model. The study provides evidence that GEP (with RMSE=17.82 l/s, MAE=6.61 l/s, CE=0.72 and R2=0.978) is capable of modeling rainfall-runoff process and is a viable alternative to other applied artificial intelligence and MLR time-series methods.

  9. Comparison of results analysis of chemical composition of alloys inside the U-Zr-Nb by XRF and AAS techniques

    International Nuclear Information System (INIS)

    Masrukan; Tri Yulianto; Anwar Muchsin

    2011-01-01

    U-Zr-Nb alloy chemical composition analysis using X Ray Fluorescence (XRF) and Atomic Absorption Spectroscopy (AAS) techniques have been conducted, where U-Zr- Nb alloy was chosen as candidates for new high-density fuel for future research reactors . Composition analysis is necessary because the composition of elements in the fuel will determine the characteristics of fuel during the fabrication process and in the reactor. The use of two kinds of analysis techniques were designed to obtain accurate analysis results. The experiment was conducted to determine the major element composition and impurities in the alloy U-Zr-Nb. First U-Zr-Nb varying alloy composition Nb were respectively 1%, 4%, 7% (U10% Zr1% Nb, U10% Zr4% Nb and U10% 7% Nb) as results of the melting process of measuring the diameter of 120 mm crushed on the surface bottom. Once on the bottom surface is smooth, then analyzed using XRF techniques. To analyze the elements using AAS techniques, alloy U-Zr-Nb cut into 10 mm x 5 mm then dissolved using HF and nitric acid. Solution that occurred were analyzed using AAS technique. From the analysis using the XRF technique is obtained the alloy U-10% Zr-1% Nb, U-10% Zr-4% Nb and Zr-10% U-7% Nb) had a content of each element as follows: U (87.8858%), Zr (2.6097%) and Nb (0.2206%), U (87.8556%), Zr (2.6302%), and Nb (0.6573%); U (84.6334%), Zr (2.5773%), and Nb (1.0940) weight. Results of analysis using AAS techniques on samples obtained third consecutive Zr content of 9.25%, 8.90% and 9.80% while the content of Nb was not detected. Meanwhile, the results of elemental analysis of impurities in all three samples showed that almost all the elements are still qualify as fuel except Zn element. Element Zn at the three samples of each alloys U-10% Zr-1% Nb, U-10% Zr-4% Nb and U-10% Zr-7%Nb is 1.3266%, 3.2756% and 1.0927% weight. It could be concluded that the results of analysis of elemental content and impurities in the alloy U-Nb-Zr using both XRF and AAS visible

  10. Comparison of Grid Nudging and Spectral Nudging Techniques for Dynamical Climate Downscaling within the WRF Model

    Science.gov (United States)

    Fan, X.; Chen, L.; Ma, Z.

    2010-12-01

    Climate downscaling has been an active research and application area in the past several decades focusing on regional climate studies. Dynamical downscaling, in addition to statistical methods, has been widely used in downscaling as the advanced modern numerical weather and regional climate models emerge. The utilization of numerical models enables that a full set of climate variables are generated in the process of downscaling, which are dynamically consistent due to the constraints of physical laws. While we are generating high resolution regional climate, the large scale climate patterns should be retained. To serve this purpose, nudging techniques, including grid analysis nudging and spectral nudging, have been used in different models. There are studies demonstrating the benefit and advantages of each nudging technique; however, the results are sensitive to many factors such as nudging coefficients and the amount of information to nudge to, and thus the conclusions are controversy. While in a companion work of developing approaches for quantitative assessment of the downscaled climate, in this study, the two nudging techniques are under extensive experiments in the Weather Research and Forecasting (WRF) model. Using the same model provides fair comparability. Applying the quantitative assessments provides objectiveness of comparison. Three types of downscaling experiments were performed for one month of choice. The first type is serving as a base whereas the large scale information is communicated through lateral boundary conditions only; the second is using the grid analysis nudging; and the third is using spectral nudging. Emphases are given to the experiments of different nudging coefficients and nudging to different variables in the grid analysis nudging; while in spectral nudging, we focus on testing the nudging coefficients, different wave numbers on different model levels to nudge.

  11. Using an inverse modelling approach to evaluate the water retention in a simple water harvesting technique

    Directory of Open Access Journals (Sweden)

    K. Verbist

    2009-10-01

    Full Text Available In arid and semi-arid zones, runoff harvesting techniques are often applied to increase the water retention and infiltration on steep slopes. Additionally, they act as an erosion control measure to reduce land degradation hazards. Nevertheless, few efforts were observed to quantify the water harvesting processes of these techniques and to evaluate their efficiency. In this study, a combination of detailed field measurements and modelling with the HYDRUS-2D software package was used to visualize the effect of an infiltration trench on the soil water content of a bare slope in northern Chile. Rainfall simulations were combined with high spatial and temporal resolution water content monitoring in order to construct a useful dataset for inverse modelling purposes. Initial estimates of model parameters were provided by detailed infiltration and soil water retention measurements. Four different measurement techniques were used to determine the saturated hydraulic conductivity (Ksat independently. The tension infiltrometer measurements proved a good estimator of the Ksat value and a proxy for those measured under simulated rainfall, whereas the pressure and constant head well infiltrometer measurements showed larger variability. Six different parameter optimization functions were tested as a combination of soil-water content, water retention and cumulative infiltration data. Infiltration data alone proved insufficient to obtain high model accuracy, due to large scatter on the data set, and water content data were needed to obtain optimized effective parameter sets with small confidence intervals. Correlation between the observed soil water content and the simulated values was as high as R2=0.93 for ten selected observation points used in the model calibration phase, with overall correlation for the 22 observation points equal to 0.85. The model results indicate that the infiltration trench has a

  12. Comparison of Analysis and Spectral Nudging Techniques for Dynamical Downscaling with the WRF Model over China

    Directory of Open Access Journals (Sweden)

    Yuanyuan Ma

    2016-01-01

    Full Text Available To overcome the problem that the horizontal resolution of global climate models may be too low to resolve features which are important at the regional or local scales, dynamical downscaling has been extensively used. However, dynamical downscaling results generally drift away from large-scale driving fields. The nudging technique can be used to balance the performance of dynamical downscaling at large and small scales, but the performances of the two nudging techniques (analysis nudging and spectral nudging are debated. Moreover, dynamical downscaling is now performed at the convection-permitting scale to reduce the parameterization uncertainty and obtain the finer resolution. To compare the performances of the two nudging techniques in this study, three sensitivity experiments (with no nudging, analysis nudging, and spectral nudging covering a period of two months with a grid spacing of 6 km over continental China are conducted to downscale the 1-degree National Centers for Environmental Prediction (NCEP dataset with the Weather Research and Forecasting (WRF model. Compared with observations, the results show that both of the nudging experiments decrease the bias of conventional meteorological elements near the surface and at different heights during the process of dynamical downscaling. However, spectral nudging outperforms analysis nudging for predicting precipitation, and analysis nudging outperforms spectral nudging for the simulation of air humidity and wind speed.

  13. Modified urethrovesical anastomosis during robot-assisted simple prostatectomy: Technique and results

    Directory of Open Access Journals (Sweden)

    Octavio Castillo

    2016-06-01

    Conclusion: The results of our study show that RASP with UVA is a feasible, secure, and reproducible procedure with low morbidity. Additional series with larger patient cohorts are needed to validate this approach.

  14. Pediatric endocanalicular diode laser dacryocystorhinostomy: results of a minimally invasive surgical technique.

    Science.gov (United States)

    Uysal, Ismail Onder; Ozçimen, Muammer; Yener, Halil Ibrahim; Kal, Ali

    2011-09-01

    The purpose of this study was to evaluate the effectiveness of endocanalicular diode laser dacryocystorhinostomy (DCR), which is a minimally invasive surgical technique, in pediatric patients with congenital nasolacrimal duct obstruction (NLDO). A retrospective study was carried out on patients treated between October 2008 and August 2009 for nasolacrimal duct obstruction with an endocanalicular diode laser procedure. Patients diagnosed as having nasolacrimal duct obstruction were included in this study and an endocanalicular diode laser procedure was performed. The main outcome measures were patients' previous treatments, clinical presentation, operative and postoperative complications, postoperative follow-up and resolution of epiphora. Eighteen children (10 girls, 8 boys) with a mean age of 6.11 ± 2.08 years (range, 4-10) underwent 20 endocanalicular laser DCR operations for congenital NLDO. In all eyes (100%), there was a history of epiphora and chronic dacryocystitis; two (10%) presented with acute dacryocystitis. Previous procedures included probing and irrigation of all eyes (100%) and silicone tube intubation in nine eyes (45%). None of the patients underwent any previous DCR operations. During a mean postoperative follow-up period of 20.50 ± 3.24 months (range, 14-24 months), the anatomical success rate (patency of ostium on nasal endoscopy) was 100%, and the clinical success rate (resolution of epiphora) was 85%. Endocanalicular diode laser DCR is an effective treatment modality for pediatric patients with congenital NLDO that compares favorably with the reported success rates of external and endoscopic endonasal DCR. Moreover, it has an added advantage of shorter operative time, less morbidity and avoidance of overnight admission.

  15. Validation techniques of agent based modelling for geospatial simulations

    OpenAIRE

    Darvishi, M.; Ahmadi, G.

    2014-01-01

    One of the most interesting aspects of modelling and simulation study is to describe the real world phenomena that have specific properties; especially those that are in large scales and have dynamic and complex behaviours. Studying these phenomena in the laboratory is costly and in most cases it is impossible. Therefore, Miniaturization of world phenomena in the framework of a model in order to simulate the real phenomena is a reasonable and scientific approach to understand the world. Agent...

  16. Modeling and Control of Multivariable Process Using Intelligent Techniques

    Directory of Open Access Journals (Sweden)

    Subathra Balasubramanian

    2010-10-01

    Full Text Available For nonlinear dynamic systems, the first principles based modeling and control is difficult to implement. In this study, a fuzzy controller and recurrent fuzzy controller are developed for MIMO process. Fuzzy logic controller is a model free controller designed based on the knowledge about the process. In fuzzy controller there are two types of rule-based fuzzy models are available: one the linguistic (Mamdani model and the other is Takagi–Sugeno model. Of these two, Takagi-Sugeno model (TS has attracted most attention. The fuzzy controller application is limited to static processes due to their feedforward structure. But, most of the real-time processes are dynamic and they require the history of input/output data. In order to store the past values a memory unit is needed, which is introduced by the recurrent structure. The proposed recurrent fuzzy structure is used to develop a controller for the two tank heating process. Both controllers are designed and implemented in a real time environment and their performance is compared.

  17. A study on the modeling techniques using LS-INGRID

    Energy Technology Data Exchange (ETDEWEB)

    Ku, J. H.; Park, S. W

    2001-03-01

    For the development of radioactive material transport packages, the verification of structural safety of a package against the free drop impact accident should be carried out. The use of LS-DYNA, which is specially developed code for impact analysis, is essential for impact analysis of the package. LS-INGRID is a pre-processor for LS-DYNA with considerable capability to deal with complex geometries and allows for parametric modeling. LS-INGRID is most effective in combination with LS-DYNA code. Although the usage of LS-INGRID seems very difficult relative to many commercial mesh generators, the productivity of users performing parametric modeling tasks with LS-INGRID can be much higher in some cases. Therefore, LS-INGRID has to be used with LS-DYNA. This report presents basic explanations for the structure and commands, basic modelling examples and advanced modelling of LS-INGRID to use it for the impact analysis of various packages. The new users can build the complex model easily, through a study for the basic examples presented in this report from the modelling to the loading and constraint conditions.

  18. Relationship Marketing results: proposition of a cognitive mapping model

    Directory of Open Access Journals (Sweden)

    Iná Futino Barreto

    2015-12-01

    Full Text Available Objective - This research sought to develop a cognitive model that expresses how marketing professionals understand the relationship between the constructs that define relationship marketing (RM. It also tried to understand, using the obtained model, how objectives in this field are achieved. Design/methodology/approach – Through cognitive mapping, we traced 35 individual mental maps, highlighting how each respondent understands the interactions between RM elements. Based on the views of these individuals, we established an aggregate mental map. Theoretical foundation – The topic is based on a literature review that explores the RM concept and its main elements. Based on this review, we listed eleven main constructs. Findings – We established an aggregate mental map that represents the RM structural model. Model analysis identified that CLV is understood as the final result of RM. We also observed that the impact of most of the RM elements on CLV is brokered by loyalty. Personalization and quality, on the other hand, proved to be process input elements, and are the ones that most strongly impact others. Finally, we highlight that elements that punish customers are much less effective than elements that benefit them. Contributions - The model was able to insert core elements of RM, but absent from most formal models: CLV and customization. The analysis allowed us to understand the interactions between the RM elements and how the end result of RM (CLV is formed. This understanding improves knowledge on the subject and helps guide, assess and correct actions.

  19. Functional results-oriented healthcare leadership: a novel leadership model.

    Science.gov (United States)

    Al-Touby, Salem Said

    2012-03-01

    This article modifies the traditional functional leadership model to accommodate contemporary needs in healthcare leadership based on two findings. First, the article argues that it is important that the ideal healthcare leadership emphasizes the outcomes of the patient care more than processes and structures used to deliver such care; and secondly, that the leadership must strive to attain effectiveness of their care provision and not merely targeting the attractive option of efficient operations. Based on these premises, the paper reviews the traditional Functional Leadership Model and the three elements that define the type of leadership an organization has namely, the tasks, the individuals, and the team. The article argues that concentrating on any one of these elements is not ideal and proposes adding a new element to the model to construct a novel Functional Result-Oriented healthcare leadership model. The recommended Functional-Results Oriented leadership model embosses the results element on top of the other three elements so that every effort on healthcare leadership is directed towards attaining excellent patient outcomes.

  20. Value of the distant future: Model-independent results

    Science.gov (United States)

    Katz, Yuri A.

    2017-01-01

    This paper shows that the model-independent account of correlations in an interest rate process or a log-consumption growth process leads to declining long-term tails of discount curves. Under the assumption of an exponentially decaying memory in fluctuations of risk-free real interest rates, I derive the analytical expression for an apt value of the long run discount factor and provide a detailed comparison of the obtained result with the outcome of the benchmark risk-free interest rate models. Utilizing the standard consumption-based model with an isoelastic power utility of the representative economic agent, I derive the non-Markovian generalization of the Ramsey discounting formula. Obtained analytical results allowing simple calibration, may augment the rigorous cost-benefit and regulatory impact analysis of long-term environmental and infrastructure projects.

  1. Storm-time ring current: model-dependent results

    Directory of Open Access Journals (Sweden)

    N. Yu. Ganushkina

    2012-01-01

    Full Text Available The main point of the paper is to investigate how much the modeled ring current depends on the representations of magnetic and electric fields and boundary conditions used in simulations. Two storm events, one moderate (SymH minimum of −120 nT on 6–7 November 1997 and one intense (SymH minimum of −230 nT on 21–22 October 1999, are modeled. A rather simple ring current model is employed, namely, the Inner Magnetosphere Particle Transport and Acceleration model (IMPTAM, in order to make the results most evident. Four different magnetic field and two electric field representations and four boundary conditions are used. We find that different combinations of the magnetic and electric field configurations and boundary conditions result in very different modeled ring current, and, therefore, the physical conclusions based on simulation results can differ significantly. A time-dependent boundary outside of 6.6 RE gives a possibility to take into account the particles in the transition region (between dipole and stretched field lines forming partial ring current and near-Earth tail current in that region. Calculating the model SymH* by Biot-Savart's law instead of the widely used Dessler-Parker-Sckopke (DPS relation gives larger and more realistic values, since the currents are calculated in the regions with nondipolar magnetic field. Therefore, the boundary location and the method of SymH* calculation are of key importance for ring current data-model comparisons to be correctly interpreted.

  2. A new technique for measuring aerosols with moonlight observations and a sky background model

    Science.gov (United States)

    Jones, Amy; Noll, Stefan; Kausch, Wolfgang; Kimeswenger, Stefan; Szyszka, Ceszary; Unterguggenberger, Stefanie

    2014-05-01

    moonlight model is designed for the average atmospheric conditions at Cerro Paranal. The Mie scattering is calculated for the average distribution of aerosol particles, but this input can be modified. We can avoid the airglow emission lines, and near full Moon the airglow continuum can be ignored. In the case study, by comparing the scattered moonlight for the various angles and wavelengths along with the extinction curve from the standard stars, we can iteratively find the optimal aerosol size distribution for the time of observation. We will present this new technique, the results from this case study, and how it can be implemented for investigating aerosols using the X-Shooter archive and other astronomical archives.

  3. Monitoring ambient ozone with a passive measurement technique method, field results and strategy

    NARCIS (Netherlands)

    Scheeren, BA; Adema, EH

    1996-01-01

    A low-cost, accurate and sensitive passive measurement method for ozone has been developed and tested. The method is based on the reaction of ozone with indigo carmine which results in colourless reaction products which are detected spectrophotometrically after exposure. Coated glass filters are

  4. Nuclear-fuel-cycle optimization: methods and modelling techniques

    International Nuclear Information System (INIS)

    Silvennoinen, P.

    1982-01-01

    This book present methods applicable to analyzing fuel-cycle logistics and optimization as well as in evaluating the economics of different reactor strategies. After an introduction to the phases of a fuel cycle, uranium cost trends are assessed in a global perspective. Subsequent chapters deal with the fuel-cycle problems faced by a power utility. The fuel-cycle models cover the entire cycle from the supply of uranium to the disposition of spent fuel. The chapter headings are: Nuclear Fuel Cycle, Uranium Supply and Demand, Basic Model of the LWR (light water reactor) Fuel Cycle, Resolution of Uncertainties, Assessment of Proliferation Risks, Multigoal Optimization, Generalized Fuel-Cycle Models, Reactor Strategy Calculations, and Interface with Energy Strategies. 47 references, 34 figures, 25 tables

  5. Near infrared spectrometric technique for testing fruit quality: optimisation of regression models using genetic algorithms

    Science.gov (United States)

    Isingizwe Nturambirwe, J. Frédéric; Perold, Willem J.; Opara, Umezuruike L.

    2016-02-01

    Near infrared (NIR) spectroscopy has gained extensive use in quality evaluation. It is arguably one of the most advanced spectroscopic tools in non-destructive quality testing of food stuff, from measurement to data analysis and interpretation. NIR spectral data are interpreted through means often involving multivariate statistical analysis, sometimes associated with optimisation techniques for model improvement. The objective of this research was to explore the extent to which genetic algorithms (GA) can be used to enhance model development, for predicting fruit quality. Apple fruits were used, and NIR spectra in the range from 12000 to 4000 cm-1 were acquired on both bruised and healthy tissues, with different degrees of mechanical damage. GAs were used in combination with partial least squares regression methods to develop bruise severity prediction models, and compared to PLS models developed using the full NIR spectrum. A classification model was developed, which clearly separated bruised from unbruised apple tissue. GAs helped improve prediction models by over 10%, in comparison with full spectrum-based models, as evaluated in terms of error of prediction (Root Mean Square Error of Cross-validation). PLS models to predict internal quality, such as sugar content and acidity were developed and compared to the versions optimized by genetic algorithm. Overall, the results highlighted the potential use of GA method to improve speed and accuracy of fruit quality prediction.

  6. Increasing the reliability of ecological models using modern software engineering techniques

    Science.gov (United States)

    Robert M. Scheller; Brian R. Sturtevant; Eric J. Gustafson; Brendan C. Ward; David J. Mladenoff

    2009-01-01

    Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and...

  7. Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells

    Energy Technology Data Exchange (ETDEWEB)

    Durlofsky, Louis J.

    2000-08-28

    This project targets the development of (1) advanced reservoir simulation techniques for modeling non-conventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and well index (for use in simulation models), including the effects of wellbore flow; and (3) accurate approaches to account for heterogeneity in the near-well region.

  8. Clinical Results After Prostatic Artery Embolization Using the PErFecTED Technique: A Single-Center Study

    International Nuclear Information System (INIS)

    Amouyal, Gregory; Thiounn, Nicolas; Pellerin, Olivier; Yen-Ting, Lin; Giudice, Costantino Del; Dean, Carole; Pereira, Helena; Chatellier, Gilles; Sapoval, Marc

    2016-01-01

    BackgroundProstatic artery embolization (PAE) has been performed for a few years, but there is no report on PAE using the PErFecTED technique outside from the team that initiated this approach.ObjectiveThis single-center retrospective open label study reports our experience and clinical results on patients suffering from symptomatic BPH, who underwent PAE aiming at using the PErFecTED technique.Materials and MethodsWe treated 32 consecutive patients, mean age 65 (52–84 years old) between December 2013 and January 2015. Patients were referred for PAE after failure of medical treatment and refusal or contra-indication to surgery. They were treated using the PErFecTED technique, when feasible, with 300–500 µm calibrated microspheres (two-night hospital stay or outpatient procedure). Follow-up was performed at 3, 6, and 12 months.ResultsWe had a 100 % immediate technical success of embolization (68 % of feasibility of the PErFecTED technique) with no immediate complications. After a mean follow-up of 7.7 months, we observed a 78 % rate of clinical success. Mean IPSS decreased from 15.3 to 4.2 (p = .03), mean QoL from 5.4 to 2 (p = .03), mean Qmax increased from 9.2 to 19.2 (p = .25), mean prostatic volume decreased from 91 to 62 (p = .009) mL. There was no retrograde ejaculation and no major complication.ConclusionPAE using the PErFecTED technique is a safe and efficient technique to treat bothersome LUTS related to BPH. It is of interest to note that the PErFecTED technique cannot be performed in some cases for anatomical reasons

  9. Clinical Results After Prostatic Artery Embolization Using the PErFecTED Technique: A Single-Center Study

    Energy Technology Data Exchange (ETDEWEB)

    Amouyal, Gregory, E-mail: gregamouyal@hotmail.com; Thiounn, Nicolas, E-mail: nicolas.thiounn@aphp.fr; Pellerin, Olivier, E-mail: olivier.pellerin@aphp.fr [Université Paris Descartes - Sorbonne - Paris - Cité, Faculté de Médecine (France); Yen-Ting, Lin, E-mail: ymerically@gmail.com [Assistance Publique - Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Interventional Radiology Department (France); Giudice, Costantino Del, E-mail: costantino.delgiudice@aphp.fr [Université Paris Descartes - Sorbonne - Paris - Cité, Faculté de Médecine (France); Dean, Carole, E-mail: carole.dean@aphp.fr [Assistance Publique - Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Interventional Radiology Department (France); Pereira, Helena, E-mail: helena.pereira@aphp.fr [Assistance Publique - Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Clinical Research Unit (France); Chatellier, Gilles, E-mail: gilles.chatellier@aphp.fr; Sapoval, Marc, E-mail: marc.sapoval2@aphp.fr [Université Paris Descartes - Sorbonne - Paris - Cité, Faculté de Médecine (France)

    2016-03-15

    BackgroundProstatic artery embolization (PAE) has been performed for a few years, but there is no report on PAE using the PErFecTED technique outside from the team that initiated this approach.ObjectiveThis single-center retrospective open label study reports our experience and clinical results on patients suffering from symptomatic BPH, who underwent PAE aiming at using the PErFecTED technique.Materials and MethodsWe treated 32 consecutive patients, mean age 65 (52–84 years old) between December 2013 and January 2015. Patients were referred for PAE after failure of medical treatment and refusal or contra-indication to surgery. They were treated using the PErFecTED technique, when feasible, with 300–500 µm calibrated microspheres (two-night hospital stay or outpatient procedure). Follow-up was performed at 3, 6, and 12 months.ResultsWe had a 100 % immediate technical success of embolization (68 % of feasibility of the PErFecTED technique) with no immediate complications. After a mean follow-up of 7.7 months, we observed a 78 % rate of clinical success. Mean IPSS decreased from 15.3 to 4.2 (p = .03), mean QoL from 5.4 to 2 (p = .03), mean Qmax increased from 9.2 to 19.2 (p = .25), mean prostatic volume decreased from 91 to 62 (p = .009) mL. There was no retrograde ejaculation and no major complication.ConclusionPAE using the PErFecTED technique is a safe and efficient technique to treat bothersome LUTS related to BPH. It is of interest to note that the PErFecTED technique cannot be performed in some cases for anatomical reasons.

  10. Estimation of genetic variability and heritability of wheat agronomic traits resulted from some gamma rays irradiation techniques

    International Nuclear Information System (INIS)

    Wijaya Murti Indriatama; Trikoesoemaningtyas; Syarifah Iis Aisyah; Soeranto Human

    2016-01-01

    Gamma irradiation techniques have significant effect on frequency and spectrum of macro-mutation but the study of its effect on micro-mutation that related to genetic variability on mutated population is very limited. The aim of this research was to study the effect of gamma irradiation techniques on genetic variability and heritability of wheat agronomic characters at M2 generation. This research was conducted from July to November 2014, at Cibadak experimental station, Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development, Ministry of Agriculture. Three introduced wheat breeding lines (F-44, Kiran-95 & WL-711) were treated by 3 gamma irradiation techniques (acute, fractionated and intermittent). M1 generation of combination treatments were planted and harvested its spike individually per plants. As M2 generation, seeds of 75 M1 spike were planted at the field with one row one spike method and evaluated on the agronomic characters and its genetic components. The used of gamma irradiation techniques decreased mean but increased range values of agronomic traits in M2 populations. Fractionated irradiation induced higher mean and wider range on spike length and number of spike let per spike than other irradiation techniques. Fractionated and intermittent irradiation resulted greater variability of grain weight per plant than acute irradiation. The number of tillers, spike weight, grain weight per spike and grain weight per plant on M2 population resulted from induction of three gamma irradiation techniques have high estimated heritability and broad sense of genetic variability coefficient values. The three gamma irradiation techniques increased genetic variability of agronomic traits on M2 populations, except plant height. (author)

  11. Comparison of QuadrapolarTM radiofrequency lesions produced by standard versus modified technique: an experimental model

    Directory of Open Access Journals (Sweden)

    Safakish R

    2017-06-01

    Full Text Available Ramin Safakish Allevio Pain Management Clinic, Toronto, ON, Canada Abstract: Lower back pain (LBP is a global public health issue and is associated with substantial financial costs and loss of quality of life. Over the years, different literature has provided different statistics regarding the causes of the back pain. The following statistic is the closest estimation regarding our patient population. The sacroiliac (SI joint pain is responsible for LBP in 18%–30% of individuals with LBP. Quadrapolar™ radiofrequency ablation, which involves ablation of the nerves of the SI joint using heat, is a commonly used treatment for SI joint pain. However, the standard Quadrapolar radiofrequency procedure is not always effective at ablating all the sensory nerves that cause the pain in the SI joint. One of the major limitations of the standard Quadrapolar radiofrequency procedure is that it produces small lesions of ~4 mm in diameter. Smaller lesions increase the likelihood of failure to ablate all nociceptive input. In this study, we compare the standard Quadrapolar radiofrequency ablation technique to a modified Quadrapolar ablation technique that has produced improved patient outcomes in our clinic. The methodology of the two techniques are compared. In addition, we compare results from an experimental model comparing the lesion sizes produced by the two techniques. Taken together, the findings from this study suggest that the modified Quadrapolar technique provides longer lasting relief for the back pain that is caused by SI joint dysfunction. A randomized controlled clinical trial is the next step required to quantify the difference in symptom relief and quality of life produced by the two techniques. Keywords: lower back pain, radiofrequency ablation, sacroiliac joint, Quadrapolar radiofrequency ablation

  12. Parameter estimation in stochastic mammogram model by heuristic optimization techniques.

    NARCIS (Netherlands)

    Selvan, S.E.; Xavier, C.C.; Karssemeijer, N.; Sequeira, J.; Cherian, R.A.; Dhala, B.Y.

    2006-01-01

    The appearance of disproportionately large amounts of high-density breast parenchyma in mammograms has been found to be a strong indicator of the risk of developing breast cancer. Hence, the breast density model is popular for risk estimation or for monitoring breast density change in prevention or

  13. Discovering Process Reference Models from Process Variants Using Clustering Techniques

    NARCIS (Netherlands)

    Li, C.; Reichert, M.U.; Wombacher, Andreas

    2008-01-01

    In today's dynamic business world, success of an enterprise increasingly depends on its ability to react to changes in a quick and flexible way. In response to this need, process-aware information systems (PAIS) emerged, which support the modeling, orchestration and monitoring of business processes

  14. Teaching Behavioral Modeling and Simulation Techniques for Power Electronics Courses

    Science.gov (United States)

    Abramovitz, A.

    2011-01-01

    This paper suggests a pedagogical approach to teaching the subject of behavioral modeling of switch-mode power electronics systems through simulation by general-purpose electronic circuit simulators. The methodology is oriented toward electrical engineering (EE) students at the undergraduate level, enrolled in courses such as "Power…

  15. Biliary System Architecture: Experimental Models and Visualization Techniques

    Czech Academy of Sciences Publication Activity Database

    Sarnová, Lenka; Gregor, Martin

    2017-01-01

    Roč. 66, č. 3 (2017), s. 383-390 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LQ1604; GA ČR GA15-23858S Institutional support: RVO:68378050 Keywords : Biliary system * Mouse model * Cholestasis * Visualisation * Morphology Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 1.461, year: 2016

  16. Testing Model with "Check Technique" for Physics Education

    Science.gov (United States)

    Demir, Cihat

    2016-01-01

    As the number, date and form of the written tests are structured and teacher-oriented, it is considered that it creates fear and anxiety among the students. It has been found necessary and important to form a testing model which will keep the students away from the test anxiety and allows them to learn only about the lesson. For this study,…

  17. Test results of the SMES model coil. Pulse performance

    International Nuclear Information System (INIS)

    Hamajima, Takataro; Shimada, Mamoru; Ono, Michitaka

    1998-01-01

    A model coil for superconducting magnetic energy storage (SMES model coil) has been developed to establish the component technologies needed for a small-scale 100 kWh SMES device. The SMES model coil was fabricated, and then performance tests were carried out in 1996. The coil was successfully charged up to around 30 kA and down to zero at the same ramp rate of magnetic field experienced in a 100 kWh SMES device. AC loss in the coil was measured by an enthalpy method as parameters of ramp rate and flat top current. The results were evaluated by an analysis and compared with short-sample test results. The measured hysteresis loss is in good agreement with that estimated from the short-sample results. It was found that the coupling loss of the coil consists of two major coupling time constants. One is a short time constant of about 200 ms, which is in agreement with the test results of a short real conductor. The other is a long time constant of about 30 s, which could not be expected from the short sample test results. (author)

  18. Modeling Results For the ITER Cryogenic Fore Pump. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Pfotenhauer, John M. [University of Wisconsin, Madison, WI (United States); Zhang, Dongsheng [University of Wisconsin, Madison, WI (United States)

    2014-03-31

    A numerical model characterizing the operation of a cryogenic fore-pump (CFP) for ITER has been developed at the University of Wisconsin – Madison during the period from March 15, 2011 through June 30, 2014. The purpose of the ITER-CFP is to separate hydrogen isotopes from helium gas, both making up the exhaust components from the ITER reactor. The model explicitly determines the amount of hydrogen that is captured by the supercritical-helium-cooled pump as a function of the inlet temperature of the supercritical helium, its flow rate, and the inlet conditions of the hydrogen gas flow. Furthermore the model computes the location and amount of hydrogen captured in the pump as a function of time. Throughout the model’s development, and as a calibration check for its results, it has been extensively compared with the measurements of a CFP prototype tested at Oak Ridge National Lab. The results of the model demonstrate that the quantity of captured hydrogen is very sensitive to the inlet temperature of the helium coolant on the outside of the cryopump. Furthermore, the model can be utilized to refine those tests, and suggests methods that could be incorporated in the testing to enhance the usefulness of the measured data.

  19. Data assimilation techniques and modelling uncertainty in geosciences

    Directory of Open Access Journals (Sweden)

    M. Darvishi

    2014-10-01

    Full Text Available "You cannot step into the same river twice". Perhaps this ancient quote is the best phrase to describe the dynamic nature of the earth system. If we regard the earth as a several mixed systems, we want to know the state of the system at any time. The state could be time-evolving, complex (such as atmosphere or simple and finding the current state requires complete knowledge of all aspects of the system. On one hand, the Measurements (in situ and satellite data are often with errors and incomplete. On the other hand, the modelling cannot be exact; therefore, the optimal combination of the measurements with the model information is the best choice to estimate the true state of the system. Data assimilation (DA methods are powerful tools to combine observations and a numerical model. Actually, DA is an interaction between uncertainty analysis, physical modelling and mathematical algorithms. DA improves knowledge of the past, present or future system states. DA provides a forecast the state of complex systems and better scientific understanding of calibration, validation, data errors and their probability distributions. Nowadays, the high performance and capabilities of DA have led to extensive use of it in different sciences such as meteorology, oceanography, hydrology and nuclear cores. In this paper, after a brief overview of the DA history and a comparison with conventional statistical methods, investigated the accuracy and computational efficiency of two main classical algorithms of DA involving stochastic DA (BLUE and Kalman filter and variational DA (3D and 4D-Var, then evaluated quantification and modelling of the errors. Finally, some of DA applications in geosciences and the challenges facing the DA are discussed.

  20. The impact of applying product-modelling techniques in configurator projects

    DEFF Research Database (Denmark)

    Hvam, Lars; Kristjansdottir, Katrin; Shafiee, Sara

    2018-01-01

    This paper aims to increase understanding of the impact of using product-modelling techniques to structure and formalise knowledge in configurator projects. Companies that provide customised products increasingly apply configurators in support of sales and design activities, reaping benefits...... that include shorter lead times, improved quality of specifications and products, and lower overall product costs. The design and implementation of configurators are a challenging task that calls for scientifically based modelling techniques to support the formal representation of configurator knowledge. Even...... the phenomenon model and information model are considered visually, (2) non-UML-based modelling techniques, in which only the phenomenon model is considered and (3) non-formal modelling techniques. This study analyses the impact to companies from increased availability of product knowledge and improved control...

  1. Development og groundwater flow modeling techniques for the low-level radwaste disposal (III)

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Dae-Seok; Kim, Chun-Soo; Kim, Kyung-Soo; Park, Byung-Yoon; Koh, Yong-Kweon; Park, Hyun-Soo [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-12-01

    The project amis to establish the methodology of hydrogeologic assessment by the field application of the evaluation techniques gained and accumulated from the previous hydrogeological research works in Korea. The results of the project and their possible areas for application are (1) acquisition of detailed hydrogeologic information by using a borehole televiewer and a multipacker system, (2) establishing an integrated hydrogeological assessment method for fractured rocks, (3) acquisition of the fracture parameters for fracture modeling, (4) an inversion analysis of hydraulic parameters from fracture network modeling, (5) geostatistical methods for the spatial assignment of hydraulic parameters for fractured rocks, and (6) establishing the groundwater flow modeling procedure for a repository. 75 refs., 72 figs., 34 tabs. (Author)

  2. Modeling, Control and Analyze of Multi-Machine Drive Systems using Bond Graph Technique

    Directory of Open Access Journals (Sweden)

    J. Belhadj

    2006-03-01

    Full Text Available In this paper, a system viewpoint method has been investigated to study and analyze complex systems using Bond Graph technique. These systems are multimachine multi-inverter based on Induction Machine (IM, well used in industries like rolling mills, textile, and railway traction. These systems are multi-domains, multi-scales time and present very strong internal and external couplings, with non-linearity characterized by a high model order. The classical study with analytic model is difficult to manipulate and it is limited to some performances. In this study, a “systemic approach” is presented to design these kinds of systems, using an energetic representation based on Bond Graph formalism. Three types of multimachine are studied with their control strategies. The modeling is carried out by Bond Graph and results are discussed to show the performances of this methodology

  3. Establishment of SHG-44 human glioma model in brain of wistar rat with stereotactic technique

    International Nuclear Information System (INIS)

    Hong Xinyu; Luo Yi'nan; Fu Shuanglin; Wang Zhanfeng; Bie Li; Cui Jiale

    2004-01-01

    Objective: To establish solid intracerebral human glioma model in Wistar rat with xenograft methods. Methods: The SHG-44 cells were injected into brain right caudate nucleus of previous immuno-inhibitory Wistar rats with stereotactic technique. The MRI scans were performed at 1 week and 2 weeks later after implantation. After 2 weeks the rats were killed and pathological examination and immunohistologic stain for human GFAP were used. Results: The MRI scan after 1 week of implantation showed the glioma was growing, pathological histochemical examination demonstrated the tumor was glioma. Human GFAP stain was positive. The growth rate of glioma model was about 60%. Conclusion: Solid intracerebral human glioma model in previous immuno-inhibitory Wistar rat is successfully established

  4. Analyzing the field of bioinformatics with the multi-faceted topic modeling technique.

    Science.gov (United States)

    Heo, Go Eun; Kang, Keun Young; Song, Min; Lee, Jeong-Hoon

    2017-05-31

    Bioinformatics is an interdisciplinary field at the intersection of molecular biology and computing technology. To characterize the field as convergent domain, researchers have used bibliometrics, augmented with text-mining techniques for content analysis. In previous studies, Latent Dirichlet Allocation (LDA) was the most representative topic modeling technique for identifying topic structure of subject areas. However, as opposed to revealing the topic structure in relation to metadata such as authors, publication date, and journals, LDA only displays the simple topic structure. In this paper, we adopt the Tang et al.'s Author-Conference-Topic (ACT) model to study the field of bioinformatics from the perspective of keyphrases, authors, and journals. The ACT model is capable of incorporating the paper, author, and conference into the topic distribution simultaneously. To obtain more meaningful results, we use journals and keyphrases instead of conferences and bag-of-words.. For analysis, we use PubMed to collected forty-six bioinformatics journals from the MEDLINE database. We conducted time series topic analysis over four periods from 1996 to 2015 to further examine the interdisciplinary nature of bioinformatics. We analyze the ACT Model results in each period. Additionally, for further integrated analysis, we conduct a time series analysis among the top-ranked keyphrases, journals, and authors according to their frequency. We also examine the patterns in the top journals by simultaneously identifying the topical probability in each period, as well as the top authors and keyphrases. The results indicate that in recent years diversified topics have become more prevalent and convergent topics have become more clearly represented. The results of our analysis implies that overtime the field of bioinformatics becomes more interdisciplinary where there is a steady increase in peripheral fields such as conceptual, mathematical, and system biology. These results are

  5. Shaded computer graphic techniques for visualizing and interpreting analytic fluid flow models

    Science.gov (United States)

    Parke, F. I.

    1981-01-01

    Mathematical models which predict the behavior of fluid flow in different experiments are simulated using digital computers. The simulations predict values of parameters of the fluid flow (pressure, temperature and velocity vector) at many points in the fluid. Visualization of the spatial variation in the value of these parameters is important to comprehend and check the data generated, to identify the regions of interest in the flow, and for effectively communicating information about the flow to others. The state of the art imaging techniques developed in the field of three dimensional shaded computer graphics is applied to visualization of fluid flow. Use of an imaging technique known as 'SCAN' for visualizing fluid flow, is studied and the results are presented.

  6. Mathematical Model and Artificial Intelligent Techniques Applied to a Milk Industry through DSM

    Science.gov (United States)

    Babu, P. Ravi; Divya, V. P. Sree

    2011-08-01

    The resources for electrical energy are depleting and hence the gap between the supply and the demand is continuously increasing. Under such circumstances, the option left is optimal utilization of available energy resources. The main objective of this chapter is to discuss about the Peak load management and overcome the problems associated with it in processing industries such as Milk industry with the help of DSM techniques. The chapter presents a generalized mathematical model for minimizing the total operating cost of the industry subject to the constraints. The work presented in this chapter also deals with the results of application of Neural Network, Fuzzy Logic and Demand Side Management (DSM) techniques applied to a medium scale milk industrial consumer in India to achieve the improvement in load factor, reduction in Maximum Demand (MD) and also the consumer gets saving in the energy bill.

  7. Continuous Measurements and Quantitative Constraints: Challenge Problems for Discrete Modeling Techniques

    Science.gov (United States)

    Goodrich, Charles H.; Kurien, James; Clancy, Daniel (Technical Monitor)

    2001-01-01

    We present some diagnosis and control problems that are difficult to solve with discrete or purely qualitative techniques. We analyze the nature of the problems, classify them and explain why they are frequently encountered in systems with closed loop control. This paper illustrates the problem with several examples drawn from industrial and aerospace applications and presents detailed information on one important application: In-Situ Resource Utilization (ISRU) on Mars. The model for an ISRU plant is analyzed showing where qualitative techniques are inadequate to identify certain failure modes and to maintain control of the system in degraded environments. We show why the solution to the problem will result in significantly more robust and reliable control systems. Finally, we illustrate requirements for a solution to the problem by means of examples.

  8. Phosphorus-32 intracavitary irradiation of cystic craniopharyngiomas: current technique and long-term results

    International Nuclear Information System (INIS)

    Pollock, Bruce E.; Lunsford, L. Dade; Kondziolka, Douglas; Levine, Geoffrey; Flickinger, John C.

    1995-01-01

    Purpose: The management of patients with craniopharyngiomas is often multifaceted and multidisciplinary. The purpose of this study was to examine the results of phosphorus-32 intracavitary irradiation in the treatment of patients with predominately cystic craniopharyngiomas. Methods and Materials: Thirty patients with cystic craniopharyngiomas underwent phosphorus-32 intracavitary irradiation at our center between 1981 and 1993. The median patient age was 26 years (range, 3-70 years). Thirteen patients had intracavitary irradiation as the primary surgery for their cystic tumors, whereas 17 patients had adjuvant intracavitary irradiation after microsurgical resection, fractionated radiotherapy, or both. Patients in the adjuvant treatment group were more likely to have preoperative anterior pituitary insufficiency (p = 0.008 Fischer exact test) and diabetes insipidus (p = 0.003 Fischer exact test). The median follow-up was 37 months (mean, 46 months, range, 7-116 months). Results: Phosphorus-32 intracavitary irradiation resulted in cyst regression in 28 of 32 treated cysts (88%). Ten patients (33%) have had tumor progression requiring further surgical intervention. Three patients (10%) died: two of tumor progression, and one of unrelated causes. Visual acuity and fields improved or remained stable in 63% of the patients. Fifteen patients had residual anterior pituitary function before intracavitary irradiation and 10 (67%) retained their preoperative endocrine status. New-onset diabetes insipidus occurred in 3 of 17 patients (18%) who had normal posterior pituitary function preoperatively. Fourteen of 20 adult patients (70%) continued to perform at their preoperative functional level; 3 of 5 pediatric patients who were age appropriate at the time of treatment continued to develop normally. No difference was noted between primary and adjuvant treatment patients with respect to cyst control, visual deterioration, or endocrine preservation after phosphorus-32

  9. Bench test results on a new technique for far-infrared polarimetry

    International Nuclear Information System (INIS)

    Barry, S.; Nieswand, C.; Prunty, S.L.; Mansfield, H.M.; O'Leary, P.

    1996-11-01

    The results of bench tests performed on a new method of combined interferometry/polarimetry for the magnetic field reconstruction of tokamak plasmas is presented. In particular, the sensitivity obtained in the polarimetric measurement shows the feasibility of Faraday rotation determination approaching a precision of ±0.2 o . The method is based on an optically pumped far-infrared (FIR) laser with a rotating polarization where both the interferometric and polarimetric information is determined from phase measurements. Specific sources which introduce disturbances in the optical arrangement and which can limit the attainment of the polarimetric precision, mentioned above, are discussed. (author) 4 figs., 6 refs

  10. Results from impression packer technique for location of fissures in boreholes in white chalk, Mors, Denmark

    International Nuclear Information System (INIS)

    Andersen, L.J.; Byrne, L.; Frykman, P.

    1981-01-01

    In connection with site investigations to evaluate the possibility of geological disposal of radioactive waste in a salt dome a Hydrogeological Programme was carried out. A number of bore holes were drilled to depths of 550 m. Geological and hydrogeological investigations were performed. The hydrogeological tests were carried out as packer tests, bottomhole tests using one packer, or straddle-packer test using two packers. In connection with these tests a rubber sleeve was installed over the packer and sidewall impressions of the hole were taken. Irregularities such as faults and fissures and possibly solution features were localized. The paper describes the method, procedure, equipment and the results achieved

  11. Surgery in older cancer patients - recent results and new techniques: worth the investment?.

    Science.gov (United States)

    van Leeuwen, Barbara L; Huisman, Monique G; Audisio, Riccardo A

    2013-01-01

    Recent developments in oncogeriatric surgery focus on several items - preoperative risk estimation and identification of frail patients and optimalization of perioperative care. New screening tools are being evaluated and show promising results. There is increasing evidence that preoperative training of frail patients might decrease the rate of postoperative complications and increase survival. The recent trend towards individualized treatment schemes will certainly be of benefit for the elderly population. More tools are becoming available to answer the most difficult question of all, namely whether surgery is the optimal treatment in this individual frail elderly oncogeriatric patient. Copyright © 2013 S. Karger AG, Basel.

  12. Comparative Analysis of Different Measurement Techniques for MLC Characterization: Preliminary Results

    International Nuclear Information System (INIS)

    Larraga-Gutierrez, J. M.; Ballesteros-Zebadua, P.; Garcia-Garduno, O. A.; Martinez-Davalos, A.; Rodriguez-Villafuerte, M.; Moreno-Jimenez, S.; Celis, M. A.

    2008-01-01

    Radiation transmission, leakage and beam penumbra are essential dosimetric parameters related to the commissioning of a multileaf collimation system. This work shows a comparative analysis of commonly used film detectors: X-OMAT V2 and EDR2 radiographic films, and GafChromic EBT registered radiochromic film. The results show that X-OMAT over-estimates radiation leakage and 80-20% beam penumbra. However, according to the reference values reported by the manufacturer for these dosimetric parameters, all three films are adequate for MLC dosimetric characterization, but special care must be taken when X-OMAT V2 film is used due to its low energy photon dependence

  13. Multidetector computed tomography of urolithiasis. Technique and results; Multidetektor-Computertomografie der Urolithiasis. Technik und Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Karul, M.; Regier, M. [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Zentrum fuer Radiologie und Endoskopie; Heuer, R. [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Zentrum fuer Operative Medizin

    2013-02-15

    The diagnosis of acute urolithiasis results from unenhanced multidetector computed tomography (MDCT). This test analyses the functional and anatomical possibility for passing an ureteral calculi, the localization and dimension of which are important parameters for further therapy. Alternatively chronic urolithiasis could be ruled out by magnetic resonance urography (MRU). MRU is the first choice especially in pregnant women and children because of radiation hygiene. Enhanced MDCT must be emphasized as an alternative to intravenous urography (IVU) for diagnosis of complex drainage of urine and suspected disorder of the involved kidney. This review illustrates the principles of different tests and the clinical relevance thereof. (orig.)

  14. Methodology and Results of Mathematical Modelling of Complex Technological Processes

    Science.gov (United States)

    Mokrova, Nataliya V.

    2018-03-01

    The methodology of system analysis allows us to draw a mathematical model of the complex technological process. The mathematical description of the plasma-chemical process was proposed. The importance the quenching rate and initial temperature decrease time was confirmed for producing the maximum amount of the target product. The results of numerical integration of the system of differential equations can be used to describe reagent concentrations, plasma jet rate and temperature in order to achieve optimal mode of hardening. Such models are applicable both for solving control problems and predicting future states of sophisticated technological systems.

  15. Modeling vertical loads in pools resulting from fluid injection

    International Nuclear Information System (INIS)

    Lai, W.; McCauley, E.W.

    1978-01-01

    Table-top model experiments were performed to investigate pressure suppression pool dynamics effects due to a postulated loss-of-coolant accident (LOCA) for the Peachbottom Mark I boiling water reactor containment system. The results guided subsequent conduct of experiments in the 1 / 5 -scale facility and provided new insight into the vertical load function (VLF). Model experiments show an oscillatory VLF with the download typically double-spiked followed by a more gradual sinusoidal upload. The load function contains a high frequency oscillation superimposed on a low frequency one; evidence from measurements indicates that the oscillations are initiated by fluid dynamics phenomena

  16. Comparison of the results of MIS-TLIF and open TLIF techniques in laborers

    Directory of Open Access Journals (Sweden)

    Daniel De Abreu Oliveira

    2014-01-01

    Full Text Available Objective: To compare clinical outcomes in laborers who have undergone open transforaminal interbody fusion (TLIF and minimally invasive transforaminal interbody fusion (MIS TLIF. Methods: 78 patients were submitted to lumbar arthrodesis by the same two spine surgeons partners from January 2008 to December 2012. Forty-one were submitted to traditional open arthrodesis and 37 to the minimally invasive procedure. Three patients were not included because they had already retired from work. The analyzed variables were length of hospitalization, length of follow-up, type of access (TILF or MIS TLIF, need for blood transfusion, percentage of improvement or worsening after surgery, pre- and postoperative VAS scale, time off work, pre-and postoperative Oswestry disability index, and general aspects of the laborers such as age, education, profession, working time, amount of daily weight carried at work, and use or not of personal protective equipment. Results: Time off work was longer in the TLIF group (average of 9.84 months compared with the MIS TLIF group (average of 3.20 months. Significant improvement in postoperative VAS and Oswestry was achieved in both groups. Average length of hospitalization was 5.73 days for the TLIF group and 2.76 days for the MIS TLIF group. Conclusions: Minimally invasive transforaminal lumbar interbody fusion presents similar results when compared to open TLIF, but has the benefits of less postoperative morbidity, shorter hospitalization times, and faster rehabilitation in laborer patients.

  17. IMAGE-BASED MODELING TECHNIQUES FOR ARCHITECTURAL HERITAGE 3D DIGITALIZATION: LIMITS AND POTENTIALITIES

    Directory of Open Access Journals (Sweden)

    C. Santagati

    2013-07-01

    Full Text Available 3D reconstruction from images has undergone a revolution in the last few years. Computer vision techniques use photographs from data set collection to rapidly build detailed 3D models. The simultaneous applications of different algorithms (MVS, the different techniques of image matching, feature extracting and mesh optimization are inside an active field of research in computer vision. The results are promising: the obtained models are beginning to challenge the precision of laser-based reconstructions. Among all the possibilities we can mainly distinguish desktop and web-based packages. Those last ones offer the opportunity to exploit the power of cloud computing in order to carry out a semi-automatic data processing, thus allowing the user to fulfill other tasks on its computer; whereas desktop systems employ too much processing time and hard heavy approaches. Computer vision researchers have explored many applications to verify the visual accuracy of 3D model but the approaches to verify metric accuracy are few and no one is on Autodesk 123D Catch applied on Architectural Heritage Documentation. Our approach to this challenging problem is to compare the 3Dmodels by Autodesk 123D Catch and 3D models by terrestrial LIDAR considering different object size, from the detail (capitals, moldings, bases to large scale buildings for practitioner purpose.

  18. Image-Based Modeling Techniques for Architectural Heritage 3d Digitalization: Limits and Potentialities

    Science.gov (United States)

    Santagati, C.; Inzerillo, L.; Di Paola, F.

    2013-07-01

    3D reconstruction from images has undergone a revolution in the last few years. Computer vision techniques use photographs from data set collection to rapidly build detailed 3D models. The simultaneous applications of different algorithms (MVS), the different techniques of image matching, feature extracting and mesh optimization are inside an active field of research in computer vision. The results are promising: the obtained models are beginning to challenge the precision of laser-based reconstructions. Among all the possibilities we can mainly distinguish desktop and web-based packages. Those last ones offer the opportunity to exploit the power of cloud computing in order to carry out a semi-automatic data processing, thus allowing the user to fulfill other tasks on its computer; whereas desktop systems employ too much processing time and hard heavy approaches. Computer vision researchers have explored many applications to verify the visual accuracy of 3D model but the approaches to verify metric accuracy are few and no one is on Autodesk 123D Catch applied on Architectural Heritage Documentation. Our approach to this challenging problem is to compare the 3Dmodels by Autodesk 123D Catch and 3D models by terrestrial LIDAR considering different object size, from the detail (capitals, moldings, bases) to large scale buildings for practitioner purpose.

  19. Results of the eruptive column model inter-comparison study

    Science.gov (United States)

    Costa, Antonio; Suzuki, Yujiro; Cerminara, M.; Devenish, Ben J.; Esposti Ongaro, T.; Herzog, Michael; Van Eaton, Alexa; Denby, L.C.; Bursik, Marcus; de' Michieli Vitturi, Mattia; Engwell, S.; Neri, Augusto; Barsotti, Sara; Folch, Arnau; Macedonio, Giovanni; Girault, F.; Carazzo, G.; Tait, S.; Kaminski, E.; Mastin, Larry G.; Woodhouse, Mark J.; Phillips, Jeremy C.; Hogg, Andrew J.; Degruyter, Wim; Bonadonna, Costanza

    2016-01-01

    This study compares and evaluates one-dimensional (1D) and three-dimensional (3D) numerical models of volcanic eruption columns in a set of different inter-comparison exercises. The exercises were designed as a blind test in which a set of common input parameters was given for two reference eruptions, representing a strong and a weak eruption column under different meteorological conditions. Comparing the results of the different models allows us to evaluate their capabilities and target areas for future improvement. Despite their different formulations, the 1D and 3D models provide reasonably consistent predictions of some of the key global descriptors of the volcanic plumes. Variability in plume height, estimated from the standard deviation of model predictions, is within ~ 20% for the weak plume and ~ 10% for the strong plume. Predictions of neutral buoyancy level are also in reasonably good agreement among the different models, with a standard deviation ranging from 9 to 19% (the latter for the weak plume in a windy atmosphere). Overall, these discrepancies are in the range of observational uncertainty of column height. However, there are important differences amongst models in terms of local properties along the plume axis, particularly for the strong plume. Our analysis suggests that the simplified treatment of entrainment in 1D models is adequate to resolve the general behaviour of the weak plume. However, it is inadequate to capture complex features of the strong plume, such as large vortices, partial column collapse, or gravitational fountaining that strongly enhance entrainment in the lower atmosphere. We conclude that there is a need to more accurately quantify entrainment rates, improve the representation of plume radius, and incorporate the effects of column instability in future versions of 1D volcanic plume models.

  20. Techniques for studies of unbinned model independent CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Bedford, Nicholas; Weisser, Constantin; Parkes, Chris; Gersabeck, Marco; Brodzicka, Jolanta; Chen, Shanzhen [University of Manchester (United Kingdom)

    2016-07-01

    Charge-Parity (CP) violation is a known part of the Standard Model and has been observed and measured in both the B and K meson systems. The observed levels, however, are insufficient to explain the observed matter-antimatter asymmetry in the Universe, and so other sources need to be found. One area of current investigation is the D meson system, where predicted levels of CP violation are much lower than in the B and K meson systems. This means that more sensitive methods are required when searching for CP violation in this system. Several unbinned model independent methods have been proposed for this purpose, all of which need to be optimised and their sensitivities compared.

  1. Palliative interstitial HDR brachytherapy for recurrent rectal cancer. Implantation techniques and results

    International Nuclear Information System (INIS)

    Kolotas, C.; Roeddiger, S.; Martin, T.; Tselis, N.; Baltas, D.; Zamboglou, N.; Strassmann, G.; Aebersold, D.M.

    2003-01-01

    Purpose: To report the methods and clinical results of CT-based interstitial high-dose-rate (HDR) brachytherapy procedures for the palliative treatment of recurrent rectal cancer. Patients and Methods: A total of 44 brachytherapy implants were performed in 38 patients. CT-guided catheter implants were performed in 34 patients under local anesthesia and sedation, and four patients were implanted intraoperatively. Of 40 CT-guided implants, 20 were done using metallic needles introduced via the sacrum and 20 were transperineal implants of plastic tubes in the presacral region. Postimplant CT scans were used for three-dimensional (3-D) conformal brachytherapy planning. Patients implanted with metallic needles were given a single fraction of 10-15 Gy using HDR 192 Ir, and those who received transperineal implants of plastic catheters were given fractionated brachytherapy, 5 Gy twice daily to a total dose of 30-40 Gy. The median tumor volume was 225 cm 3 with a range of 41-2,103 cm 3 . Results: After a median follow-up of 23.4 months, a total of 13/38 patients were alive. The median postbrachytherapy survival was 15 months with 18 of the 25 deaths due to distant metastases. Tumor response was as follows: 6/38 partial remission, 28/38 stable disease, and 4/38 local progression. A planning target volume (PTV) coverage > 85% was achieved in 42/44 implants. The treatment was well tolerated, and no acute complications were observed. One patient developed a fistula after 8 months. Pain relief was recorded in 34 patients (89.5%), and the median duration of this palliative effect was 5 months with a range of 1-13 months. Conclusions: Interstitial HDR brachytherapy is a valuable tool for the delivery of high doses and achieves effective palliation in recurrent rectal carcinoma. (orig.)

  2. Palliative interstitial HDR brachytherapy for recurrent rectal cancer. Implantation techniques and results

    Energy Technology Data Exchange (ETDEWEB)

    Kolotas, C. [Dept. of Radiation Oncology, Offenbach Hospital, Offenbach (Germany); Dept. of Radio-Oncology, Univ. of Bern, Inselspital, Bern (Switzerland); Roeddiger, S.; Martin, T.; Tselis, N.; Baltas, D.; Zamboglou, N. [Dept. of Radiation Oncology, Offenbach Hospital, Offenbach (Germany); Strassmann, G. [Dept. of Radiotherapy, Univ. Hospital, Philipps Univ., Marburg (Germany); Aebersold, D.M. [Dept. of Radio-Oncology, Univ. of Bern, Inselspital, Bern (Switzerland)

    2003-07-01

    Purpose: To report the methods and clinical results of CT-based interstitial high-dose-rate (HDR) brachytherapy procedures for the palliative treatment of recurrent rectal cancer. Patients and Methods: A total of 44 brachytherapy implants were performed in 38 patients. CT-guided catheter implants were performed in 34 patients under local anesthesia and sedation, and four patients were implanted intraoperatively. Of 40 CT-guided implants, 20 were done using metallic needles introduced via the sacrum and 20 were transperineal implants of plastic tubes in the presacral region. Postimplant CT scans were used for three-dimensional (3-D) conformal brachytherapy planning. Patients implanted with metallic needles were given a single fraction of 10-15 Gy using HDR {sup 192}Ir, and those who received transperineal implants of plastic catheters were given fractionated brachytherapy, 5 Gy twice daily to a total dose of 30-40 Gy. The median tumor volume was 225 cm{sup 3} with a range of 41-2,103 cm{sup 3}. Results: After a median follow-up of 23.4 months, a total of 13/38 patients were alive. The median postbrachytherapy survival was 15 months with 18 of the 25 deaths due to distant metastases. Tumor response was as follows: 6/38 partial remission, 28/38 stable disease, and 4/38 local progression. A planning target volume (PTV) coverage > 85% was achieved in 42/44 implants. The treatment was well tolerated, and no acute complications were observed. One patient developed a fistula after 8 months. Pain relief was recorded in 34 patients (89.5%), and the median duration of this palliative effect was 5 months with a range of 1-13 months. Conclusions: Interstitial HDR brachytherapy is a valuable tool for the delivery of high doses and achieves effective palliation in recurrent rectal carcinoma. (orig.)

  3. Thermodynamic Spectrum of Solar Flares Based on SDO/EVE Observations: Techniques and First Results

    Science.gov (United States)

    Wang, Yuming; Zhou, Zhenjun; Zhang, Jie; Liu, Kai; Liu, Rui; Shen, Chenglong; Chamberlin, Phillip C.

    2016-01-01

    The Solar Dynamics Observatory (SDO)/EUV Variability Experiment (EVE) provides rich information on the thermodynamic processes of solar activities, particularly on solar flares. Here, we develop a method to construct thermodynamic spectrum (TDS) charts based on the EVE spectral lines. This tool could potentially be useful for extreme ultraviolet (EUV) astronomy to learn about the eruptive activities on distant astronomical objects. Through several cases, we illustrate what we can learn from the TDS charts. Furthermore, we apply the TDS method to 74 flares equal to or greater than the M5.0 class, and reach the following statistical results. First, EUV peaks are always behind the soft X-ray (SXR) peaks and stronger flares tend to have faster cooling rates. There is a power-law correlation between the peak delay times and the cooling rates, suggesting a coherent cooling process of flares from SXR to EUV emissions. Second, there are two distinct temperature drift patterns, called Type I and Type II. For Type I flares, the enhanced emission drifts from high to low temperature like a quadrilateral, whereas for Type II flares the drift pattern looks like a triangle. Statistical analysis suggests that Type II flares are more impulsive than Type I flares. Third, for late-phase flares, the peak intensity ratio of the late phase to the main phase is roughly correlated with the flare class, and the flares with a strong late phase are all confined. We believe that the re-deposition of the energy carried by a flux rope, which unsuccessfully erupts out, into thermal emissions is responsible for the strong late phase found in a confined flare. Furthermore, we show the signatures of the flare thermodynamic process in the chromosphere and transition region in the TDS charts. These results provide new clues to advance our understanding of the thermodynamic processes of solar flares and associated solar eruptions, e.g., coronal mass ejections.

  4. Laparoscopic central pancreatectomy: Our technique and long-term results in 14 patients

    Directory of Open Access Journals (Sweden)

    Palanisamy Senthilnathan

    2015-01-01

    Full Text Available Introduction: Conventional pancreatic resections may be unnecessary for benign tumours or for tumours of low malignant potential located in the neck and body of pancreas. Such extensive resections can place the patient at increased risk of developing postoperative exocrine and endocrine insufficiency. Central pancreatectomy is a plausible surgical option for the management of tumours located in these locations. Laparoscopic approach seems appropriate for such small tumours situated deep in the retroperitoneum. Aims: To assess the technical feasibility, safety and long-term results of laparoscopic central pancreatectomy in patients with benign and low malignant potential tumours involving the neck and body of pancreas. Settings and Design: This study was an observational study which reports a single-centre experience with laparoscopic central pancreatectomy over a 9-year period. Materials and Methods: 14 patients underwent laparoscopic central pancreatectomy from October 2004 to September 2013. These included patients with tumours located in the neck and body of pancreas that were radiologically benign-looking tumours of less than 3 cm in size. Statistical Analysis Used: The statistical analysis was done using GraphPad Prism software. Results: The mean age of patients was 48.93 years. The mean operative time was 239.7 min. Mean blood loss was 153.2 ml. Mean postoperative ICU stay was 1.2 days and overall mean hospital stay was 8.07 days. There were no mortalities and no major postoperative complications. Margins were negative in all cases and with a median follow-up of 44 months, there was no recurrence. Conclusions: Laparoscopic central pancreatectomy is a feasible procedure with acceptable morbidity. In the long term, there were no recurrences and pancreatic function was well preserved.

  5. Application of the weighted total field-scattering field technique to 3D-PSTD light scattering model

    Science.gov (United States)

    Hu, Shuai; Gao, Taichang; Liu, Lei; Li, Hao; Chen, Ming; Yang, Bo

    2018-04-01

    PSTD (Pseudo Spectral Time Domain) is an excellent model for the light scattering simulation of nonspherical aerosol particles. However, due to the particularity of its discretization form of the Maxwell's equations, the traditional Total Field/Scattering Field (TF/SF) technique for FDTD (Finite Differential Time Domain) is not applicable to PSTD, and the time-consuming pure scattering field technique is mainly applied to introduce the incident wave. To this end, the weighted TF/SF technique proposed by X. Gao is generalized and applied to the 3D-PSTD scattering model. Using this technique, the incident light can be effectively introduced by modifying the electromagnetic components in an inserted connecting region between the total field and the scattering field region with incident terms, where the incident terms are obtained by weighting the incident field by a window function. To optimally determine the thickness of connection region and the window function type for PSTD calculations, their influence on the modeling accuracy is firstly analyzed. To further verify the effectiveness and advantages of the weighted TF/SF technique, the improved PSTD model is validated against the PSTD model equipped with pure scattering field technique in both calculation accuracy and efficiency. The results show that, the performance of PSTD seems to be not sensitive to variation of window functions. The number of the connection layer required decreases with the increasing of spatial resolution, where for spatial resolution of 24 grids per wavelength, a 6-layer region is thick enough. The scattering phase matrices and integral scattering parameters obtained by the improved PSTD show an excellent consistency with those well-tested models for spherical and nonspherical particles, illustrating that the weighted TF/SF technique can introduce the incident precisely. The weighted TF/SF technique shows higher computational efficiency than pure scattering technique.

  6. Initial CGE Model Results Summary Exogenous and Endogenous Variables Tests

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-08-07

    The following discussion presents initial results of tests of the most recent version of the National Infrastructure Simulation and Analysis Center Dynamic Computable General Equilibrium (CGE) model developed by Los Alamos National Laboratory (LANL). The intent of this is to test and assess the model’s behavioral properties. The test evaluated whether the predicted impacts are reasonable from a qualitative perspective. This issue is whether the predicted change, be it an increase or decrease in other model variables, is consistent with prior economic intuition and expectations about the predicted change. One of the purposes of this effort is to determine whether model changes are needed in order to improve its behavior qualitatively and quantitatively.

  7. Gonioscopy-assisted transluminal trabeculotomy, ab interno trabeculotomy: technique report and preliminary results.

    Science.gov (United States)

    Grover, Davinder S; Godfrey, David G; Smith, Oluwatosin; Feuer, William J; Montes de Oca, Ildamaris; Fellman, Ronald L

    2014-04-01

    To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. Retrospective, noncomparative cases series. Eighty-five eyes of 85 consecutive patients who sought treatment at Glaucoma Associates of Texas with uncontrolled open-angle glaucoma and underwent gonioscopy-assisted transluminal trabeculotomy (GATT) for whom there was at least 6 months of follow-up data. Retrospective chart review of patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., O.S., R.L.F.) between October 2011 and October 2012. The surgery was performed in adults with various open-angle glaucomas. Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. Eighty-five patients with an age range of 24 to 88 years underwent GATT with at least 6 months of follow-up. In 57 patients with primary open-angle glaucoma, the IOP decreased by 7.7 mmHg (standard deviation [SD], 6.2 mm Hg; 30.0% [SD, 22.7%]) with an average decrease in glaucoma medications of 0.9 (SD, 1.3) at 6 months. In this group, the IOP decreased by 11.1 mmHg (SD, 6.1 mmHg; 39.8% [SD, 16.0%]) with 1.1 fewer glaucoma medications at 12 months. In the secondary glaucoma group of 28 patients, IOP decreased by 17.2 mmHg (SD, 10.8 mmHg; 52.7% [SD, 15.8%]) with an average of 2.2 fewer glaucoma medications at 6 months. In this group, the IOP decreased by 19.9 mmHg (SD, 10.2 mmHg; 56.8% [SD, 17.4%]) with an average of 1.9 fewer medications (SD, 2.1) at 12 months. Treatment was considered to have failed in 9% (8/85) of patients because of the need for further glaucoma surgery. The cumulative proportion of failure at 1 year ranged from 0.1 to 0.32, depending on the group. Lens status or concurrent cataract surgery did not have a statistically significant effect on IOP in eyes that underwent GATT at either 6 or 12 months (P > 0.35). The most common complication was transient hyphema, seen in

  8. Transanal minimally-invasive surgery (TAMIS: Technique and results from an initial experience

    Directory of Open Access Journals (Sweden)

    Carlos Ramon Silveira Mendes

    2013-10-01

    Full Text Available Transanal endoscopic microsurgery is a minimally-invasive approach for rectal lesions. Superior exposure and access to the entire rectum result in lesser risk of compromised margins and lower recurrence rates, when compared to conventional transanal excision. The aim of this study was to describe a single institution's initial experience with transanal minimally invasive surgery (TAMIS. This was a prospective review of our database. Elev- en procedures from January 2012 to June 2013 were analyzed. Results: eleven operations were completed. Five men were evaluated. Mean age was 62.9 (40-86. Mean follow-up was 9.3 (2-17 months. Average tumor size was 3.8 (1.8-8 cm. Mean distance from anal verge was 6.3 (3-12 cm. Mean operating time was 53.73 (28-118 min. Postoperative complica- tion rate was 9.1%. There were no readmissions. Mortality was null. Operative pathology disclosed the presence of adenoma in four patients, invasive adenocarcinoma in two, neu- roendocrine carcinoma in three, and no residual lesion in one case. TAMIS is a minimally- invasive procedure with low postoperative morbidity at the initial experience. TAMIS is a curative procedure for benign lesions and for selected early cancers. It is useful after neoadjuvant therapy for strictly selected cancers, pending the results of multi-institutional trials. Resumo: Microcirurgia endoscópica transanal é uma abordagem minimamente invasiva para lesões retais. Apresenta menor risco de margem comprometida e menores taxas de recorrência em comparação com excisão transanal convencional. Objetivou-se descrever a experiência inicial, de uma única instituição, com cirurgia minimamente invasiva transanal (TAMIS. Avaliação prospectiva de nosso banco de dados. Onze procedimentos de janeiro de 2012 a junho de 2013, foram analisados. Resultados: onze operações foram concluídas. Havia cinco homens. A média de idade foi de 62,9 (40-86. O acompanhamento médio foi de ww9,3 (2-17 meses. O

  9. Seed dispersal into wetlands: Techniques and results for a restored tidal freshwater marsh

    Science.gov (United States)

    Neff, K.P.; Baldwin, A.H.

    2005-01-01

    Although seed dispersal is assumed to be a major factor determining plant community development in restored wetlands, little research exists on density and species richness of seed available through dispersal in these systems. We measured composition and seed dispersal rates at a restored tidal freshwater marsh in Washington, DC, USA by collecting seed dispersing through water and wind. Seed dispersal by water was measured using two methods of seed collection: (1) stationary traps composed of coconut fiber mat along an elevation gradient bracketing the tidal range and (2) a floating surface trawl net attached to a boat. To estimate wind dispersal rates, we collected seed from stationary traps composed of coconut fiber mat positioned above marsh vegetation. We also collected a small number of samples of debris deposited along high tide lines (drift lines) and feces of Canada Goose to explore their seed content. We used the seedling emergence method to determine seed density in all samples, which involved placing the fiber mats or sample material on top of potting soil in a greenhouse misting room and enumerating emerging seedlings. Seedlings from a total of 125 plant species emerged during this study (including 82 in river trawls, 89 in stationary water traps, 21 in drift lines, 39 in wind traps, and 10 in goose feces). The most abundant taxa included Bidens frondosa, Boehmeria cylindrica, Cyperus spp., Eclipta prostrata, and Ludwigia palustris. Total seedling density was significantly greater for the stationary water traps (212 + 30.6 seeds/m2/month) than the equal-sized stationary wind traps (18 + 6.0 seeds/m(2)/month). Lower-bound estimates of total species richness based on the non-parametric Chao 2 asymptotic estimators were greater for seeds in water (106 + 1.4 for stationary water traps and 104 + 5.5 for trawl samples) than for wind (54 + 6.4). Our results indicate that water is the primary source of seeds dispersing to the site and that a species-rich pool

  10. THERMODYNAMIC SPECTRUM OF SOLAR FLARES BASED ON SDO/EVE OBSERVATIONS: TECHNIQUES AND FIRST RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuming; Zhou, Zhenjun; Liu, Kai; Liu, Rui; Shen, Chenglong [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhang, Jie [School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, MSN 6A2, Fairfax, VA 22030 (United States); Chamberlin, Phillip C., E-mail: ymwang@ustc.edu.cn [Solar Physics Laboratory, Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2016-03-15

    The Solar Dynamics Observatory (SDO)/EUV Variability Experiment (EVE) provides rich information on the thermodynamic processes of solar activities, particularly on solar flares. Here, we develop a method to construct thermodynamic spectrum (TDS) charts based on the EVE spectral lines. This tool could potentially be useful for extreme ultraviolet (EUV) astronomy to learn about the eruptive activities on distant astronomical objects. Through several cases, we illustrate what we can learn from the TDS charts. Furthermore, we apply the TDS method to 74 flares equal to or greater than the M5.0 class, and reach the following statistical results. First, EUV peaks are always behind the soft X-ray (SXR) peaks and stronger flares tend to have faster cooling rates. There is a power-law correlation between the peak delay times and the cooling rates, suggesting a coherent cooling process of flares from SXR to EUV emissions. Second, there are two distinct temperature drift patterns, called Type I and Type II. For Type I flares, the enhanced emission drifts from high to low temperature like a quadrilateral, whereas for Type II flares the drift pattern looks like a triangle. Statistical analysis suggests that Type II flares are more impulsive than Type I flares. Third, for late-phase flares, the peak intensity ratio of the late phase to the main phase is roughly correlated with the flare class, and the flares with a strong late phase are all confined. We believe that the re-deposition of the energy carried by a flux rope, which unsuccessfully erupts out, into thermal emissions is responsible for the strong late phase found in a confined flare. Furthermore, we show the signatures of the flare thermodynamic process in the chromosphere and transition region in the TDS charts. These results provide new clues to advance our understanding of the thermodynamic processes of solar flares and associated solar eruptions, e.g., coronal mass ejections.

  11. A review on reflective remote sensing and data assimilation techniques for enhanced agroecosystem modeling

    Science.gov (United States)

    Dorigo, W. A.; Zurita-Milla, R.; de Wit, A. J. W.; Brazile, J.; Singh, R.; Schaepman, M. E.

    2007-05-01

    During the last 50 years, the management of agroecosystems has been undergoing major changes to meet the growing demand for food, timber, fibre and fuel. As a result of this intensified use, the ecological status of many agroecosystems has been severely deteriorated. Modeling the behavior of agroecosystems is, therefore, of great help since it allows the definition of management strategies that maximize (crop) production while minimizing the environmental impacts. Remote sensing can support such modeling by offering information on the spatial and temporal variation of important canopy state variables which would be very difficult to obtain otherwise. In this paper, we present an overview of different methods that can be used to derive biophysical and biochemical canopy state variables from optical remote sensing data in the VNIR-SWIR regions. The overview is based on an extensive literature review where both statistical-empirical and physically based methods are discussed. Subsequently, the prevailing techniques of assimilating remote sensing data into agroecosystem models are outlined. The increasing complexity of data assimilation methods and of models describing agroecosystem functioning has significantly increased computational demands. For this reason, we include a short section on the potential of parallel processing to deal with the complex and computationally intensive algorithms described in the preceding sections. The studied literature reveals that many valuable techniques have been developed both for the retrieval of canopy state variables from reflective remote sensing data as for assimilating the retrieved variables in agroecosystem models. However, for agroecosystem modeling and remote sensing data assimilation to be commonly employed on a global operational basis, emphasis will have to be put on bridging the mismatch between data availability and accuracy on one hand, and model and user requirements on the other. This could be achieved by

  12. Joining of polymer-metal lightweight structures using self-piercing riveting (SPR) technique: Numerical approach and simulation results

    Science.gov (United States)

    Amro, Elias; Kouadri-Henni, Afia

    2018-05-01

    Restrictions in pollutant emissions dictated at the European Commission level in the past few years have urged mass production car manufacturers to engage rapidly several strategies in order to reduce significantly the energy consumption of their vehicles. One of the most relevant taken action is light-weighting of body in white (BIW) structures, concretely visible with the increased introduction of polymer-based composite materials reinforced by carbon/glass fibers. However, the design and manufacturing of such "hybrid" structures is limiting the use of conventional assembly techniques like resistance spot welding (RSW) which are not transferable as they are for polymer-metal joining. This research aims at developing a joining technique that would eventually enable the assembly of a sheet molding compound (SMC) polyester thermoset-made component on a structure composed of several high strength steel grades. The state of the art of polymer-metal joining techniques highlighted the few ones potentially able to respond to the industrial challenge, which are: structural bonding, self-piercing riveting (SPR), direct laser joining and friction spot welding (FSpW). In this study, the promising SPR technique is investigated. Modelling of SPR process in the case of polymer-metal joining was performed through the building of a 2D axisymmetric FE model using the commercial code Abaqus CAE 6.10-1. Details of the numerical approach are presented with a particular attention to the composite sheet for which Mori-Tanaka's homogenization method is used in order to estimate overall mechanical properties. Large deformations induced by the riveting process are enabled with the use of a mixed finite element formulation ALE (arbitrary Lagrangian-Eulerian). FE model predictions are compared with experimental data followed by a discussion.

  13. Ultrasound-guided endocavitary drainage of pelvic abscesses: Technique, results and complications

    International Nuclear Information System (INIS)

    Ryan, R.S.; McGrath, F P.; Haslam, P.J.; Varghese, J.C.; Lee, M.J.

    2003-01-01

    AIM: To evaluate the experience in our institution with ultrasound-guided transrectal and transvaginal (endocavitary) drainage of pelvic abscesses. MATERIALS AND METHODS: Eighteen patients (four male, 14 female; mean age 55 years, range 30-78 years) presenting with pelvic abscesses were referred to our institution for therapeutic drainage over a 4 year period. Patients received broad-spectrum antibiotics prior to drainage, which was performed by either the transvaginal or transrectal route under ultrasound guidance. Patients were given sedo-analgesia in the form of midazolam and fentanyl and local anaesthesia was also employed. Eight French catheters were inserted into the abscess cavities, and patients were subsequently monitored on a daily basis by a member of the interventional radiology team until such time as it was deemed appropriate to remove the catheter. RESULTS: Eighteen catheters were placed in 17 patients, and transvaginal aspiration alone was performed in one patient. Drainage was successful in 16 of 17 patients, but a transgluteal approach was ultimately required in the remaining patient to enable passage of a larger catheter into an infected haematoma. The mean duration of drainage was 5 days, mean time to defervesce 2 days. Spontaneous catheter dislodgement occurred in four patients associated with straining, but this did not have any adverse effect in three of the four patients. CONCLUSION: Endocavitary drainage is an effective method of treatment for pelvic abscesses. Spontaneous catheter dislodgement does not affect patient outcome

  14. Ultrasound-guided endocavitary drainage of pelvic abscesses: Technique, results and complications

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, R.S.; McGrath, F P.; Haslam, P.J.; Varghese, J.C.; Lee, M.J

    2003-01-01

    AIM: To evaluate the experience in our institution with ultrasound-guided transrectal and transvaginal (endocavitary) drainage of pelvic abscesses. MATERIALS AND METHODS: Eighteen patients (four male, 14 female; mean age 55 years, range 30-78 years) presenting with pelvic abscesses were referred to our institution for therapeutic drainage over a 4 year period. Patients received broad-spectrum antibiotics prior to drainage, which was performed by either the transvaginal or transrectal route under ultrasound guidance. Patients were given sedo-analgesia in the form of midazolam and fentanyl and local anaesthesia was also employed. Eight French catheters were inserted into the abscess cavities, and patients were subsequently monitored on a daily basis by a member of the interventional radiology team until such time as it was deemed appropriate to remove the catheter. RESULTS: Eighteen catheters were placed in 17 patients, and transvaginal aspiration alone was performed in one patient. Drainage was successful in 16 of 17 patients, but a transgluteal approach was ultimately required in the remaining patient to enable passage of a larger catheter into an infected haematoma. The mean duration of drainage was 5 days, mean time to defervesce 2 days. Spontaneous catheter dislodgement occurred in four patients associated with straining, but this did not have any adverse effect in three of the four patients. CONCLUSION: Endocavitary drainage is an effective method of treatment for pelvic abscesses. Spontaneous catheter dislodgement does not affect patient outcome.

  15. Training in atomic science and techniques. Some results of the IAEA fellowship programme

    International Nuclear Information System (INIS)

    1963-01-01

    The International Atomic Energy Agency has regarded the creation of adequate facilities for training in nuclear science and technology as an essential step towards the development of the peaceful uses of atomic energy throughout the world. It has also been clear that this is one of the fields in which the Agency an give most fruitful assistance to its Member States: by awarding fellowships for training at advanced centres of study and research, by instituting visiting professorships to train scientific and technical personnel in their home countries, by organizing international and regional training courses or training centres. The Agency has made use of all these methods and more than 60 countries have benefited from its training programme. A part of the programme is financed out of voluntary contributions by Member States to the Agency's General Fund and some of it financed out of funds made available to the Agency under the UN Expanded Programme of Technical Assistance (EPTA). In addition, use is made of training facilities provided free by several Member States. In an attempt to assess some of the concrete results of the training programme, the Agency recently sent a special questionnaire to 151 former Agency fellows who had completed their training at least two years earlier. By the end of last year, replies had been received from 121 former fellows from 31 countries. They provide an encouraging picture, as can be seen from the numerical analysis

  16. Training in atomic science and techniques. Some results of the IAEA fellowship programme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1963-04-15

    The International Atomic Energy Agency has regarded the creation of adequate facilities for training in nuclear science and technology as an essential step towards the development of the peaceful uses of atomic energy throughout the world. It has also been clear that this is one of the fields in which the Agency an give most fruitful assistance to its Member States: by awarding fellowships for training at advanced centres of study and research, by instituting visiting professorships to train scientific and technical personnel in their home countries, by organizing international and regional training courses or training centres. The Agency has made use of all these methods and more than 60 countries have benefited from its training programme. A part of the programme is financed out of voluntary contributions by Member States to the Agency's General Fund and some of it financed out of funds made available to the Agency under the UN Expanded Programme of Technical Assistance (EPTA). In addition, use is made of training facilities provided free by several Member States. In an attempt to assess some of the concrete results of the training programme, the Agency recently sent a special questionnaire to 151 former Agency fellows who had completed their training at least two years earlier. By the end of last year, replies had been received from 121 former fellows from 31 countries. They provide an encouraging picture, as can be seen from the numerical analysis

  17. Status of disposal techniques for spent fuel in Germany: Results of demonstration tests for direct disposal

    International Nuclear Information System (INIS)

    Engelmann, H.J.; Filbert, W.

    1993-01-01

    According to the Atomic Energy Act (1985) the Federal Government is responsible for establishing facilities to indemnify and dispose radioactive waste. According to Art. 9b of the Atomic Energy Act (1986) the construction and operation of such a repository requires approval of a plan. According to safety criteria applicable for disposing radioactive waste in mines, construction and operation of repository mines require application of acknowledged rules of technology, laws, ordinances and other regulations to protect operating staff and population from radiation damages. Shaft hoisting equipment for the transportation of radioactive waste in a repository mine must satisfy normal operational tasks and meet special safety-requirements. Its failure may result in danger for persons, release of radioactive substances into the plant and environment. That means, shaft hoisting equipment must be designed to satisfy the necessary safety requirements and be state of the art of science and technology. The aim of these demonstration tests is verification of technical feasibility of a shaft hoisting equipment with a payload of 85 t, underground for drift disposal of POLLUX-casks, and essential machine and mine-technical systems and components. The demonstration also includes safe radiation protection during transport and disposal operations. Investigations assume that radioactive waste is transported in containers that satisfy transport requirements for dangerous goods and have a type-B-certificate

  18. Intraoperative Ir-192 implantation for early breast cancer. Techniques and results

    International Nuclear Information System (INIS)

    Mansfield, C.M.

    1990-01-01

    Patients with early breast cancer (T1-2 N0-1) can be treated by lumpectomy and irradiation with a local control and survival equal to more radical surgery. Between 1982 and 1988, 323 patients with early breast cancer were treated, when possible, with Ir-192 implants at the time of lumpectomy to a local dose of 2000 cGy in 40-50 hours. Ten to 14 days later, the whole breast was treated to 4500 cGy at 180 per fraction in 5 weeks. The 6-year actuarial survival for stages I and II disease was 98% and 91%, respectively, and the recurrence-free survival was 96% and 98%, respectively. When these 323 patients were evaluated by T status, a local control of 97% was the same for T1 and T2 lesions. The cosmetic results were good to excellent in 95% of the patients. This approach has improved our ability to accurately place the boost dose in the breast

  19. Medial release and lateral imbrication for intractable anterior knee pain: diagnostic process, technique, and results

    Directory of Open Access Journals (Sweden)

    Meldrum AR

    2015-01-01

    Full Text Available Alexander R Meldrum,1 Jeremy R Reed,2 Megan D Dash3 1Department of Surgery, Section of Orthopedic Surgery, University of Calgary, Calgary, AB, Canada; 2Department of Surgery, University of Saskatchewan College of Medicine, Regina, SK, Canada; 3Department of Family Medicine, College of Medicine, University of Saskatchewan, Regina, SK, Canada Purpose: To present two cases of intractable patellofemoral pain syndrome treated with a novel procedure, arthroscopic medial release, and lateral imbrication of the patellar retinaculum. Patients and methods: This case series presents the treatment of three knees in two patients (one bilateral in whom an all-inside arthroscopic medial release and lateral imbrication of the patellar retinaculum was performed. Subjective measurement of pain was the primary outcome measurement, and subjective patellofemoral instability was the secondary outcome measurement. Results: Subjectively the two patients had full resolution of their pain, without any patellofemoral instability. Conclusion: Medial release and lateral imbrication of the patellar retinaculum is a new surgical procedure that has been used in the treatment of intractable patellofemoral pain syndrome. This is the first report of its kind in the literature. While outcome measurements were less than ideal, the patients had positive outcomes, both functionally and in terms of pain. Keywords: anterior knee pain syndrome, chondromalacia patellae, runners knee, patellar chondropathy, patellofemoral dysfunction, patellofemoral tracking disorder

  20. Single- or multiple-visit endodontics: which technique results in fewest postoperative problems?

    Science.gov (United States)

    Balto, Khaled

    2009-01-01

    The Cochrane Central Register of Controlled Trials, Medline, Embase, six thesis databases (Networked Digital Library of Theses and Dissertations, Proquest Digital Dissertations, OAIster, Index to Theses, Australian Digital Thesis Program and Dissertation.com) and one conference report database (BIOSIS Previews) were searched. There were no language restrictions. Studies were included if subjects had a noncontributory medical history; underwent nonsurgical root canal treatment during the study; there was comparison between single- and multiple-visit root canal treatment; and if outcome was measured in terms of pain degree or prevalence of flare-up. Data were extracted using a standard data extraction sheet. Because of variations in recorded outcomes and methodological and clinical heterogeneity, a meta-analysis was not carried out, although a qualitative synthesis was presented. Sixteen studies fitted the inclusion criteria in the review, with sample size varying from 60-1012 cases. The prevalence of postoperative pain ranged from 3-58%. The heterogeneity of the included studies was far too great to yield meaningful results from a meta-analysis. Compelling evidence is lacking to indicate any significantly different prevalence of postoperative pain or flare-up following either single- or multiple-visit root canal treatment.

  1. Optimizing hydraulic cleaning techniques for oiled coarse sediment beaches : long-term monitoring results

    International Nuclear Information System (INIS)

    Mauseth, G.S.; Graham, A.W.; Simon, J.; Sergy, G.A.

    2004-01-01

    This paper presents the results of a study in which shoreline cobbles in British Columbia were oiled with Bunker C oil and then hydraulically cleaned using a variety of water pressures and temperatures. The oiling took place in 1997. Epifauna and epiflora abundances were quantified prior to exposure, 28 to 72 hours and one year following treatment, and up to 6 years post-treatment. The study revealed that after six years of treatment, there was no statistical difference between any of the treatment groups, including the un-oiled, un-treated control or the oiled, treated control. The exposure to oil and a variety of pressure and temperature washing treatments did not differentially influence epibiota abundances 6 years after treatment. It was concluded that there is no long-term increased benefit or damage to the epibiota from hydraulic washing treatments. However, hydraulic cleaning can cause negative, short-term effects. Therefore, the immediate priority after an oil spill should be to remove the oil in order to limit remobilization. Organism abundances did not return to pre-treatment values. Even the un-oiled/un-treated control substances were significantly lower after 6 years, suggesting that extreme cold temperatures may have played a more important role in controlling organism abundances than did the oiling or treatments. 10 refs., 1 tab., 10 figs

  2. Adult spinal deformity treated with minimally invasive surgery. Description of surgical technique, radiological results and literature review.

    Science.gov (United States)

    Domínguez, I; Luque, R; Noriega, M; Rey, J; Alía, J; Urda, A; Marco, F

    The prevalence of adult spinal deformity has been increasing exponentially over time. Surgery has been credited with good radiological and clinical results. The incidence of complications is high. MIS techniques provide good results with fewer complications. This is a retrospective study of 25 patients with an adult spinal deformity treated by MIS surgery, with a minimum follow-up of 6 months. Radiological improvement was SVA from 5 to 2cm, coronal Cobb angle from 31° to 6°, and lumbar lordosis from 18° to 38°. All of these parameters remained stable over time. We also present the complications that appeared in 4 patients (16%). Only one patient needed reoperation. We describe the technique used and review the references on the subject. We conclude that the MIS technique for treating adult spinal deformity has comparable results to those of the conventional techniques but with fewer complications. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Comparison of the cytology technique and the frozen section results in intraoperative consultation of the breast lesions

    Directory of Open Access Journals (Sweden)

    "Haeri H

    2002-07-01

    Full Text Available The cytology study is effective and reliable technique in intraoperative consultation. This study was performed to evaluate the accuracy of the cytology study in intraoperative consultation of the breast lesions. 125 specimens of the breast lesions were examined and studied in Imam Khomeini Hospital during the years 1998-99. The sensitivity, specificity and accuracy for cytological method were 87.5% , 95%, 90.5% and for the frozen section 92.4%, 100% and 95.4% respectively. The false positive reports were 2% in the cytology technique and the most important source of error and false postivie reports was fibroadenoma in this method. By reviewing the results. It could be concluded that combination of these two techniques is beneficial and more reliable in intraoperative consultation resports of the breast lesions

  4. Capturing and Modeling Domain Knowledge Using Natural Language Processing Techniques

    Science.gov (United States)

    2005-06-01

    Intelligence Artificielle , France, May 2001, p. 109- 118 [Barrière, 2001] -----. “Investigating the Causal Relation in Informative Texts”. Terminology, 7:2...out of the flood of information, military have to create new ways of processing sensor and intelligence information, and of providing the results to...have to create new ways of processing sensor and intelligence information, and of providing the results to commanders who must take timely operational

  5. Modern EMC analysis techniques II models and applications

    CERN Document Server

    Kantartzis, Nikolaos V

    2008-01-01

    The objective of this two-volume book is the systematic and comprehensive description of the most competitive time-domain computational methods for the efficient modeling and accurate solution of modern real-world EMC problems. Intended to be self-contained, it performs a detailed presentation of all well-known algorithms, elucidating on their merits or weaknesses, and accompanies the theoretical content with a variety of applications. Outlining the present volume, numerical investigations delve into printed circuit boards, monolithic microwave integrated circuits, radio frequency microelectro

  6. Matrix Results and Techniques in Quantum Information Science and Related Topics

    Science.gov (United States)

    Pelejo, Diane Christine

    In this dissertation, we present several matrix-related problems and results motivated by quantum information theory. Some background material of quantum information science will be discussed in chapter 1, while chapter 7 gives a summary of results and concluding remarks. In chapter 2, we look at 2n x 2 n unitary matrices, which describe operations on a closed n-qubit system. We define a set of simple quantum gates, called controlled single qubit gates, and their associated operational cost. We then present a recurrence scheme to decompose a general 2n x 2n unitary matrix to the product of no more than 2n-12n-1 single qubit gates with small number of controls. In chapter 3, we address the problem of finding a specific element phi among a given set of quantum channels S that will produce the optimal value of a scalar function D(rho 1,phi(rho2)), on two fixed quantum states rho 1 and rho2. Some of the functions we considered for D(·,·) are the trace distance, quantum fidelity and quantum relative entropy. We discuss the optimal solution when S is the set of unitary quantum channels, the set of mixed unitary channels, the set of unital quantum channels, and the set of all quantum channels. In chapter 4, we focus on the spectral properties of qubit-qudit bipartite states with a maximally mixed qudit subsystem. More specifically, given positive numbers a1 ≥ ... ≥ a 2n ≥ 0, we want to determine if there exist a 2n x 2n density matrix rho having eigenvalues a1,..., a2n and satisfying tr 1(rho)=1/n In. This problem is a special case of the more general quantum marginal problem. We give the minimal necessary and sufficient conditions on a1,..., a2n for n ≤ 6 and state some observations on general values of n.. In chapter 5, we discuss the numerical method of alternating projections and illustrate its usefulness in: (a) constructing a quantum channel, if it exists, such that phi(rho(1))=sigma(1),...,phi(rho (k))=sigma(k) for given rho (1),...,rho(k) ∈ Dn and

  7. Long-term results of aortic root repair using the reimplantation technique.

    Science.gov (United States)

    David, Tirone E; Armstrong, Susan; Manlhiot, Cedric; McCrindle, Brian W; Feindel, Christopher M

    2013-03-01

    Aortic valve sparing is frequently performed to treat patients with aortic root aneurysm, but there is an inadequate amount of information regarding its long-term durability. This study examines the long-term results of reimplantation of the aortic valve in patients with aortic root aneurysms. From August 1989 to December 2010, 296 consecutive patients had reimplantation of the aortic valve into a tubular Dacron graft. Their mean age was 45 years (range, 11-79 years), and 78% were men. Of the patients, 36% had Marfan syndrome and 11% had bicuspid aortic valve. Patients were followed prospectively with periodic images of the aortic root and remaining aorta. The mean follow-up was 6.9 ± 4.5 years. There were 21 patients at risk at 15 years. There were 4 operative and 18 late deaths. The survival at 5, 10, and 15 years was 95.1% ± 3.5%, 93.1% ± 4.4%, and 76.5% ± 18%, respectively. Only 3 patients required reoperation on the aortic valve; all 3 patients had the Bentall procedure. Freedom from reoperation at 5, 10, and 15 years was 99.7% ± 2.0%, 97.8% ± 5.3%, and 97.8% ± 5.3%, respectively. During follow-up, moderate aortic insufficiency developed in 9 patients, and severe aortic insufficiency developed in 2 patients. Freedom from moderate or severe aortic insufficiency at 5, 10, and 15 years was 98.3% ± 3.5%, 92.9% ± 6.5%, and 89.4% ± 12%, respectively. The function of the aortic valve implanted inside a tubular Dacron graft remains normal at 15 years in most patients after this type of aortic valve-sparing operation. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  8. First experiments results about the engineering model of Rapsodie

    International Nuclear Information System (INIS)

    Chalot, A.; Ginier, R.; Sauvage, M.

    1964-01-01

    This report deals with the first series of experiments carried out on the engineering model of Rapsodie and on an associated sodium facility set in a laboratory hall of Cadarache. It conveys more precisely: 1/ - The difficulties encountered during the erection and assembly of the engineering model and a compilation of the results of the first series of experiments and tests carried out on this installation (loading of the subassemblies preheating, thermal chocks...). 2/ - The experiments and tests carried out on the two prototypes control rod drive mechanisms which brought to the choice for the design of the definitive drive mechanism. As a whole, the results proved the validity of the general design principles adopted for Rapsodie. (authors) [fr

  9. Comparision of results between two different techniques of cranio-cervical decompression in patients with Chiari I malformation.

    Science.gov (United States)

    Kunert, Przemysław; Janowski, Mirosław; Zakrzewska, Agnieszka; Marchel, Andrzej

    2009-01-01

    A variety of approaches are employed for treatment of Chiari I malformation. They differ in extent of cranio-c ervical decompression. A technique based on arachnoid preservation and duroplasty was introduced in our department in 2001. The aim of the study is to compare between the previous and the present technique. Retrospective analysis of 38 patients with Chiari I malformation treated between 1998 and 2004 was performed. The previous technique including arach- noid incision, coagulation of cerebellar tonsils, and fourth ventricle exploration without duroplasty was used to treat 21 patients (group 1). A further 17 patients were treated with the present technique consisting of arachnoid preservation and duroplasty (group 2). Complication rates as well as early and late results of treatment were evaluated. Karnofsky (KPS), Rankin (RS) and Bidziński (BS) scales were used for evaluation of results. Post-operative complications were detected in 9 patients in group 1 (43%). They included liquorrhoea (5 cases), meningitis (1 case), and symptoms progression (3 cases). There were no surgical complications in group 2 (p = 0.002). Neurological improvement in the early period (until discharge from hospital) occurred in 10 (48%) patients in group 1 and in 13 (76%) in group 2 (p = NS). Further improvement or lack of symptoms progression was found in 58% in group 1 and 82% in group 2 (p = NS). Assessment in KPS, RS and BS showed slightly better results of group 2 but the difference was statistically insignificant. Results of both techniques are comparable. The risk of post-operative complications after extra-arachnoid cranio-cervical decompression with duroplasty is, however, significantly lower.

  10. Acoustic results of the Boeing model 360 whirl tower test

    Science.gov (United States)

    Watts, Michael E.; Jordan, David

    1990-09-01

    An evaluation is presented for whirl tower test results of the Model 360 helicopter's advanced, high-performance four-bladed composite rotor system intended to facilitate over-200-knot flight. During these performance measurements, acoustic data were acquired by seven microphones. A comparison of whirl-tower tests with theory indicate that theoretical prediction accuracies vary with both microphone position and the inclusion of ground reflection. Prediction errors varied from 0 to 40 percent of the measured signal-to-peak amplitude.

  11. Exact results for the one dimensional asymmetric exclusion model

    International Nuclear Information System (INIS)

    Derrida, B.; Evans, M.R.; Pasquier, V.

    1993-01-01

    The asymmetric exclusion model describes a system of particles hopping in a preferred direction with hard core repulsion. These particles can be thought of as charged particles in a field, as steps of an interface, as cars in a queue. Several exact results concerning the steady state of this system have been obtained recently. The solution consists of representing the weights of the configurations in the steady state as products of non-commuting matrices. (author)

  12. Recent results of studies of plasma fluctuations in stellarators by microwave scattering technique

    International Nuclear Information System (INIS)

    Skvortsova, N.N.; Batanov, G.M.; Kolik, L.V.; Petrov, A.E.; Pshenichnikov, A.A.; Sarksyan, K.A.; Kharchev, N.K.; Khol'nov, Yu.V.; Kubo, S.; Sanchez, J.

    2005-01-01

    -harmonic scattering. New results were obtained with the use of a small-angle scattering of the heating gyrotron radiation in LHD. In TJ-II, plasma density fluctuations were studied in experiments with the neutral beam injection. The experiments showed the presence of distinct quasi-harmonics in the first stage of the heating pulse. Simultaneously with these fluctuations, quasi-harmonics with the same frequencies were detected in the fluctuation signals of magnetic probes. Long time samples of density fluctuations (more than a million points at a sampling rate of 5 MHz) have for the first time measured. (author)

  13. Subsidies to cytogenetic dosimetry technique generated from analysis of results of Goiania radiological accident

    International Nuclear Information System (INIS)

    Ramalho, Adriana Teixeira

    1993-06-01

    Following the Goiania radiation accident, which occurred in September of 1987, peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequency of unstable chromosomal aberrations (dicentrics and centric rings) to estimate absorbed radiation dose. During the emergency period, the doses were assessed to help immediate medical treatment. After this initial estimation, doses were reassessed using in vitro calibration curves produced after the accident, more suitable for the conditions prevailing in Goiania. Dose estimates for 24 subjects exceeded 0,5 Gy. Among those, 15 individuals exceeded 1,0 Gy and 5 exceeded 3,0 Gy. None of the estimates exceeded 6,0 Gy. Four of the subjects died. During the emergency period, a cytogenetic follow-up of 14 of the exposed patients was started, aiming to observe the mean lifetime of lymphocytes containing dicentric and ring aberrations. The results suggest that for the highly exposed individuals the disappearance rate of unstable aberrations follows a two- term exponential function. Up to 470 days after the exposure, there is a rapid fall in the aberration frequency. After 470 days, the disappearance rate is very slow, almost constant. The estimated average half-time of elimination of dicentrics and rings among the highly exposed group (> 1 Gy) was 140 days for the initial period after the exposure (up to 470 days). This value is significantly shorter than the usually accepted value of 3 years reported in the literature. Mean disappearance functions of unstable chromosome aberrations were inferred, to be applied in accident situations in which there is a blood sampling delay. Statistical analysis of possible correlations between the individual half-times and biological parameters, such as sex, age, leukopenia level shown during the critical period, absorbed dose (initial frequency of chromosomal aberrations) and the administration of the bone marrow stimulating factor (rHuGM-CSF) was

  14. Review of Current Standard Model Results in ATLAS

    CERN Document Server

    Brandt, Gerhard; The ATLAS collaboration

    2018-01-01

    This talk highlights results selected from the Standard Model research programme of the ATLAS Collaboration at the Large Hadron Collider. Results using data from $p-p$ collisions at $\\sqrt{s}=7,8$~TeV in LHC Run-1 as well as results using data at $\\sqrt{s}=13$~TeV in LHC Run-2 are covered. The status of cross section measurements from soft QCD processes and jet production as well as photon production are presented. The presentation extends to vector boson production with associated jets. Precision measurements of the production of $W$ and $Z$ bosons, including a first measurement of the mass of the $W$ bosons, $m_W$, are discussed. The programme to measure electroweak processes with di-boson and tri-boson final states is outlined. All presented measurements are compatible with Standard Model descriptions and allow to further constrain it. In addition they allow to probe new physics which would manifest through extra gauge couplings, or Standard Model gauge couplings deviating from their predicted value.

  15. Application of nonliner reduction techniques in chemical process modeling: a review

    International Nuclear Information System (INIS)

    Muhaimin, Z; Aziz, N.; Abd Shukor, S.R.

    2006-01-01

    Model reduction techniques have been used widely in engineering fields for electrical, mechanical as well as chemical engineering. The basic idea of reduction technique is to replace the original system by an approximating system with much smaller state-space dimension. A reduced order model is more beneficial to process and industrial field in terms of control purposes. This paper is to provide a review on application of nonlinear reduction techniques in chemical processes. The advantages and disadvantages of each technique reviewed are also highlighted

  16. Current control design for three-phase grid-connected inverters using a pole placement technique based on numerical models

    OpenAIRE

    Citro, Costantino; Gavriluta, Catalin; Nizak Md, H. K.; Beltran, H.

    2012-01-01

    This paper presents a design procedure for linear current controllers of three-phase grid-connected inverters. The proposed method consists in deriving a numerical model of the converter by using software simulations and applying the pole placement technique to design the controller with the desired performances. A clear example on how to apply the technique is provided. The effectiveness of the proposed design procedure has been verified through the experimental results obtained with ...

  17. MODELLING THE DELAMINATION FAILURE ALONG THE CFRP-CFST BEAM INTERACTION SURFACE USING DIFFERENT FINITE ELEMENT TECHNIQUES

    Directory of Open Access Journals (Sweden)

    AHMED W. AL-ZAND

    2017-01-01

    Full Text Available Nonlinear finite element (FE models are prepared to investigate the behaviour of concrete-filled steel tube (CFST beams strengthened by carbon fibre reinforced polymer (CFRP sheets. The beams are strengthened from the bottom side only by varied sheet lengths (full and partial beam lengths and then subjected to ultimate flexural loads. Three surface interaction techniques are used to implement the bonding behaviour between the steel tube and the CFRP sheet, namely, full tie interaction (TI, cohesive element (CE and cohesive behaviour (CB techniques using ABAQUS software. Results of the comparison between the FE analysis and existing experimental study confirm that the FE models with the TI technique could be applicable for beams strengthened by CFRP sheets with a full wrapping length; the technique could not accurately implement the CFRP delamination failure, which occurred for beams with a partial wrapping length. Meanwhile, the FE models with the CE and CB techniques are applicable in the implementation of both CFRP failures (rapture and delamination for both full and partial wrapping lengths, respectively. Where, the ultimate loads' ratios achieved by the FE models using TI, CE and CB techniques about 1.122, 1.047 and 1.045, respectively, comparing to the results of existing experimental tests.

  18. Nuclear fuel cycle optimization - methods and modelling techniques

    International Nuclear Information System (INIS)

    Silvennoinen, P.

    1982-01-01

    This book is aimed at presenting methods applicable in the analysis of fuel cycle logistics and optimization as well as in evaluating the economics of different reactor strategies. After a succinct introduction to the phases of a fuel cycle, uranium cost trends are assessed in a global perspective and subsequent chapters deal with the fuel cycle problems faced by a power utility. A fundamental material flow model is introduced first in the context of light water reactor fuel cycles. Besides the minimum cost criterion, the text also deals with other objectives providing for a treatment of cost uncertainties and of the risk of proliferation of nuclear weapons. Methods to assess mixed reactor strategies, comprising also other reactor types than the light water reactor, are confined to cost minimization. In the final Chapter, the integration of nuclear capacity within a generating system is examined. (author)

  19. Advancing botnet modeling techniques for military and security simulations

    Science.gov (United States)

    Banks, Sheila B.; Stytz, Martin R.

    2011-06-01

    Simulation environments serve many purposes, but they are only as good as their content. One of the most challenging and pressing areas that call for improved content is the simulation of bot armies (botnets) and their effects upon networks and computer systems. Botnets are a new type of malware, a type that is more powerful and potentially dangerous than any other type of malware. A botnet's power derives from several capabilities including the following: 1) the botnet's capability to be controlled and directed throughout all phases of its activity, 2) a command and control structure that grows increasingly sophisticated, and 3) the ability of a bot's software to be updated at any time by the owner of the bot (a person commonly called a bot master or bot herder.) Not only is a bot army powerful and agile in its technical capabilities, a bot army can be extremely large, can be comprised of tens of thousands, if not millions, of compromised computers or it can be as small as a few thousand targeted systems. In all botnets, their members can surreptitiously communicate with each other and their command and control centers. In sum, these capabilities allow a bot army to execute attacks that are technically sophisticated, difficult to trace, tactically agile, massive, and coordinated. To improve our understanding of their operation and potential, we believe that it is necessary to develop computer security simulations that accurately portray bot army activities, with the goal of including bot army simulations within military simulation environments. In this paper, we investigate issues that arise when simulating bot armies and propose a combination of the biologically inspired MSEIR infection spread model coupled with the jump-diffusion infection spread model to portray botnet propagation.

  20. Behavioral and macro modeling using piecewise linear techniques

    NARCIS (Netherlands)

    Kruiskamp, M.W.; Leenaerts, D.M.W.; Antao, B.

    1998-01-01

    In this paper we will demonstrate that most digital, analog as well as behavioral components can be described using piecewise linear approximations of their real behavior. This leads to several advantages from the viewpoint of simulation. We will also give a method to store the resulting linear

  1. Comparison of transient PCRV model test results with analysis

    International Nuclear Information System (INIS)

    Marchertas, A.H.; Belytschko, T.B.

    1979-01-01

    Comparisons are made of transient data derived from simple models of a reactor containment vessel with analytical solutions. This effort is a part of the ongoing process of development and testing of the DYNAPCON computer code. The test results used in these comparisons were obtained from scaled models of the British sodium cooled fast breeder program. The test structure is a scaled model of a cylindrically shaped reactor containment vessel made of concrete. This concrete vessel is prestressed axially by holddown bolts spanning the top and bottom slabs along the cylindrical walls, and is also prestressed circumferentially by a number of cables wrapped around the vessel. For test purposes this containment vessel is partially filled with water, which comes in direct contact with the vessel walls. The explosive charge is immersed in the pool of water and is centrally suspended from the top of the vessel. The load history was obtained from an ICECO analysis, using the equations of state for the source and the water. A detailed check of this solution was made to assure that the derived loading did provide the correct input. The DYNAPCON code was then used for the analysis of the prestressed concrete containment model. This analysis required the simulation of prestressing and the response of the model to the applied transient load. The calculations correctly predict the magnitudes of displacements of the PCRV model. In addition, the displacement time histories obtained from the calculations reproduce the general features of the experimental records: the period elongation and amplitude increase as compared to an elastic solution, and also the absence of permanent displacement. However, the period still underestimates the experiment, while the amplitude is generally somewhat large

  2. Thermal-Chemical Model Of Subduction: Results And Tests

    Science.gov (United States)

    Gorczyk, W.; Gerya, T. V.; Connolly, J. A.; Yuen, D. A.; Rudolph, M.

    2005-12-01

    Seismic structures with strong positive and negative velocity anomalies in the mantle wedge above subduction zones have been interpreted as thermally and/or chemically induced phenomena. We have developed a thermal-chemical model of subduction, which constrains the dynamics of seismic velocity structure beneath volcanic arcs. Our simulations have been calculated over a finite-difference grid with (201×101) to (201×401) regularly spaced Eulerian points, using 0.5 million to 10 billion markers. The model couples numerical thermo-mechanical solution with Gibbs energy minimization to investigate the dynamic behavior of partially molten upwellings from slabs (cold plumes) and structures associated with their development. The model demonstrates two chemically distinct types of plumes (mixed and unmixed), and various rigid body rotation phenomena in the wedge (subduction wheel, fore-arc spin, wedge pin-ball). These thermal-chemical features strongly perturb seismic structure. Their occurrence is dependent on the age of subducting slab and the rate of subduction.The model has been validated through a series of test cases and its results are consistent with a variety of geological and geophysical data. In contrast to models that attribute a purely thermal origin for mantle wedge seismic anomalies, the thermal-chemical model is able to simulate the strong variations of seismic velocity existing beneath volcanic arcs which are associated with development of cold plumes. In particular, molten regions that form beneath volcanic arcs as a consequence of vigorous cold wet plumes are manifest by > 20% variations in the local Poisson ratio, as compared to variations of ~ 2% expected as a consequence of temperature variation within the mantle wedge.

  3. Studies on acoustic modelling techniques for CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chatoorgoon, V; Zhou, R [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

    1996-12-31

    This paper reviews the current technology being used to predict acoustic resonance in fluid-filled piping systems. The paper also reports on the analysis of a simple benchmark experiment that yielded some valuable insights and understanding into acoustic damping. A volumetric drag formula for the ABAQUS code is presented. Its application in experiments has yielded better results than previously obtained using a constant volumetric drag. (author). 24 refs., 1 tab., 12 figs.

  4. Studies on acoustic modelling techniques for CANDU reactors

    International Nuclear Information System (INIS)

    Chatoorgoon, V.; Zhou, R.

    1995-01-01

    This paper reviews the current technology being used to predict acoustic resonance in fluid-filled piping systems. The paper also reports on the analysis of a simple benchmark experiment that yielded some valuable insights and understanding into acoustic damping. A volumetric drag formula for the ABAQUS code is presented. Its application in experiments has yielded better results than previously obtained using a constant volumetric drag. (author). 24 refs., 1 tab., 12 figs

  5. Multivariate moment closure techniques for stochastic kinetic models

    International Nuclear Information System (INIS)

    Lakatos, Eszter; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H.

    2015-01-01

    Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs

  6. Multivariate moment closure techniques for stochastic kinetic models

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, Eszter, E-mail: e.lakatos13@imperial.ac.uk; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H., E-mail: m.stumpf@imperial.ac.uk [Department of Life Sciences, Centre for Integrative Systems Biology and Bioinformatics, Imperial College London, London SW7 2AZ (United Kingdom)

    2015-09-07

    Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs.

  7. Subsurface stormflow modeling with sensitivity analysis using a Latin-hypercube sampling technique

    International Nuclear Information System (INIS)

    Gwo, J.P.; Toran, L.E.; Morris, M.D.; Wilson, G.V.

    1994-09-01

    Subsurface stormflow, because of its dynamic and nonlinear features, has been a very challenging process in both field experiments and modeling studies. The disposal of wastes in subsurface stormflow and vadose zones at Oak Ridge National Laboratory, however, demands more effort to characterize these flow zones and to study their dynamic flow processes. Field data and modeling studies for these flow zones are relatively scarce, and the effect of engineering designs on the flow processes is poorly understood. On the basis of a risk assessment framework and a conceptual model for the Oak Ridge Reservation area, numerical models of a proposed waste disposal site were built, and a Latin-hypercube simulation technique was used to study the uncertainty of model parameters. Four scenarios, with three engineering designs, were simulated, and the effectiveness of the engineering designs was evaluated. Sensitivity analysis of model parameters suggested that hydraulic conductivity was the most influential parameter. However, local heterogeneities may alter flow patterns and result in complex recharge and discharge patterns. Hydraulic conductivity, therefore, may not be used as the only reference for subsurface flow monitoring and engineering operations. Neither of the two engineering designs, capping and French drains, was found to be effective in hydrologically isolating downslope waste trenches. However, pressure head contours indicated that combinations of both designs may prove more effective than either one alone

  8. Measurement model choice influenced randomized controlled trial results.

    Science.gov (United States)

    Gorter, Rosalie; Fox, Jean-Paul; Apeldoorn, Adri; Twisk, Jos

    2016-11-01

    In randomized controlled trials (RCTs), outcome variables are often patient-reported outcomes measured with questionnaires. Ideally, all available item information is used for score construction, which requires an item response theory (IRT) measurement model. However, in practice, the classical test theory measurement model (sum scores) is mostly used, and differences between response patterns leading to the same sum score are ignored. The enhanced differentiation between scores with IRT enables more precise estimation of individual trajectories over time and group effects. The objective of this study was to show the advantages of using IRT scores instead of sum scores when analyzing RCTs. Two studies are presented, a real-life RCT, and a simulation study. Both IRT and sum scores are used to measure the construct and are subsequently used as outcomes for effect calculation. The bias in RCT results is conditional on the measurement model that was used to construct the scores. A bias in estimated trend of around one standard deviation was found when sum scores were used, where IRT showed negligible bias. Accurate statistical inferences are made from an RCT study when using IRT to estimate construct measurements. The use of sum scores leads to incorrect RCT results. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Techniques and results

    Digital Repository Service at National Institute of Oceanography (India)

    Mudholkar, A.V.; Pattan, J.N.; Sudhakar, M.

    India Ltd (EIL) and Metallurgical and Engineering Consultants (MECON) were involved in the database management R & D efforts in the extraction of metallurgy of the nodules was started by various leading research centres in the country Efforts to develop...

  10. A complex-plane strategy for computing rotating polytropic models - Numerical results for strong and rapid differential rotation

    International Nuclear Information System (INIS)

    Geroyannis, V.S.

    1990-01-01

    In this paper, a numerical method, called complex-plane strategy, is implemented in the computation of polytropic models distorted by strong and rapid differential rotation. The differential rotation model results from a direct generalization of the classical model, in the framework of the complex-plane strategy; this generalization yields very strong differential rotation. Accordingly, the polytropic models assume extremely distorted interiors, while their boundaries are slightly distorted. For an accurate simulation of differential rotation, a versatile method, called multiple partition technique is developed and implemented. It is shown that the method remains reliable up to rotation states where other elaborate techniques fail to give accurate results. 11 refs

  11. Is the Linear Modeling Technique Good Enough for Optimal Form Design? A Comparison of Quantitative Analysis Models

    Science.gov (United States)

    Lin, Yang-Cheng; Yeh, Chung-Hsing; Wang, Chen-Cheng; Wei, Chun-Chun

    2012-01-01

    How to design highly reputable and hot-selling products is an essential issue in product design. Whether consumers choose a product depends largely on their perception of the product image. A consumer-oriented design approach presented in this paper helps product designers incorporate consumers' perceptions of product forms in the design process. The consumer-oriented design approach uses quantification theory type I, grey prediction (the linear modeling technique), and neural networks (the nonlinear modeling technique) to determine the optimal form combination of product design for matching a given product image. An experimental study based on the concept of Kansei Engineering is conducted to collect numerical data for examining the relationship between consumers' perception of product image and product form elements of personal digital assistants (PDAs). The result of performance comparison shows that the QTTI model is good enough to help product designers determine the optimal form combination of product design. Although the PDA form design is used as a case study, the approach is applicable to other consumer products with various design elements and product images. The approach provides an effective mechanism for facilitating the consumer-oriented product design process. PMID:23258961

  12. SR-Site groundwater flow modelling methodology, setup and results

    International Nuclear Information System (INIS)

    Selroos, Jan-Olof; Follin, Sven

    2010-12-01

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken three groundwater flow modelling studies. These are performed within the SR-Site project and represent time periods with different climate conditions. The simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. Three time periods are addressed; the Excavation and operational phases, the Initial period of temperate climate after closure, and the Remaining part of the reference glacial cycle. The present report is a synthesis of the background reports describing the modelling methodology, setup, and results. It is the primary reference for the conclusions drawn in a SR-Site specific context concerning groundwater flow during the three climate periods. These conclusions are not necessarily provided explicitly in the background reports, but are based on the results provided in these reports. The main results and comparisons presented in the present report are summarised in the SR-Site Main report

  13. Geochemical controls on shale groundwaters: Results of reaction path modeling

    International Nuclear Information System (INIS)

    Von Damm, K.L.; VandenBrook, A.J.

    1989-03-01

    The EQ3NR/EQ6 geochemical modeling code was used to simulate the reaction of several shale mineralogies with different groundwater compositions in order to elucidate changes that may occur in both the groundwater compositions, and rock mineralogies and compositions under conditions which may be encountered in a high-level radioactive waste repository. Shales with primarily illitic or smectitic compositions were the focus of this study. The reactions were run at the ambient temperatures of the groundwaters and to temperatures as high as 250/degree/C, the approximate temperature maximum expected in a repository. All modeling assumed that equilibrium was achieved and treated the rock and water assemblage as a closed system. Graphite was used as a proxy mineral for organic matter in the shales. The results show that the presence of even a very small amount of reducing mineral has a large influence on the redox state of the groundwaters, and that either pyrite or graphite provides essentially the same results, with slight differences in dissolved C, Fe and S concentrations. The thermodynamic data base is inadequate at the present time to fully evaluate the speciation of dissolved carbon, due to the paucity of thermodynamic data for organic compounds. In the illitic cases the groundwaters resulting from interaction at elevated temperatures are acid, while the smectitic cases remain alkaline, although the final equilibrium mineral assemblages are quite similar. 10 refs., 8 figs., 15 tabs

  14. Loss of spent fuel pool cooling PRA: Model and results

    International Nuclear Information System (INIS)

    Siu, N.; Khericha, S.; Conroy, S.; Beck, S.; Blackman, H.

    1996-09-01

    This letter report documents models for quantifying the likelihood of loss of spent fuel pool cooling; models for identifying post-boiling scenarios that lead to core damage; qualitative and quantitative results generated for a selected plant that account for plant design and operational practices; a comparison of these results and those generated from earlier studies; and a review of available data on spent fuel pool accidents. The results of this study show that for a representative two-unit boiling water reactor, the annual probability of spent fuel pool boiling is 5 x 10 -5 and the annual probability of flooding associated with loss of spent fuel pool cooling scenarios is 1 x 10 -3 . Qualitative arguments are provided to show that the likelihood of core damage due to spent fuel pool boiling accidents is low for most US commercial nuclear power plants. It is also shown that, depending on the design characteristics of a given plant, the likelihood of either: (a) core damage due to spent fuel pool-associated flooding, or (b) spent fuel damage due to pool dryout, may not be negligible

  15. SR-Site groundwater flow modelling methodology, setup and results

    Energy Technology Data Exchange (ETDEWEB)

    Selroos, Jan-Olof (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Follin, Sven (SF GeoLogic AB, Taeby (Sweden))

    2010-12-15

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken three groundwater flow modelling studies. These are performed within the SR-Site project and represent time periods with different climate conditions. The simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. Three time periods are addressed; the Excavation and operational phases, the Initial period of temperate climate after closure, and the Remaining part of the reference glacial cycle. The present report is a synthesis of the background reports describing the modelling methodology, setup, and results. It is the primary reference for the conclusions drawn in a SR-Site specific context concerning groundwater flow during the three climate periods. These conclusions are not necessarily provided explicitly in the background reports, but are based on the results provided in these reports. The main results and comparisons presented in the present report are summarised in the SR-Site Main report.

  16. XRF analyses for the study of painting technique and degradation on frescoes by Beato Angelico: first results

    International Nuclear Information System (INIS)

    Mazzinghi, A.

    2014-01-01

    Beato Angelico is one of the most important Italian painters of the Renaissance period, in particular he was a master of the so-called 'Buon fresco' technique for mural paintings. A wide diagnostic campaign with X-Ray Fluorescence (XRF) analyses has been carried out on three masterworks painted by Beato Angelico in the San Marco monastery in Florence: the Crocifissione con Santi, the 'Annunciazione' and the 'Madonna delle Ombre'. The latter is painted by mixing fresco and secco techniques, which makes it of particular interest for the study of two different paintings techniques of the same artist. Then the aim of the study was focused on the characterization of the painting palette, and therefore the painting techniques, used by Beato Angelico. Moreover, the conservators were interested in the study of degradation processes and old restoration treatments. Our analyses have been carried out by means of the XRF spectrometer developed at LABEC laboratory at Istituto Nazionale di Fisica Nucleare in Florence (Italy). XRF is indeed especially suited for such a kind of study, allowing for multi-elemental, nondestructive, non-invasive analyses in a short time, with portable instruments. In this paper the first results concerning the XRF analysis are presented.

  17. Subluxation of iris-sutured intraocular lenses and results of a closed chamber technique for repositioning after penetrating keratoplasty.

    Science.gov (United States)

    Jabbur, Nada S; Akpek, Esen Karamursel; Stark, Walter J

    2005-05-01

    To describe subluxation of iris-fixated intraocular lenses (IOLs) after penetrating keratoplasty (PK) as a postoperative complication and report the long-term outcomes of a closed-chamber refixation technique used in the management. This was a retrospective, noncomparative interventional case series in which 19 consecutive patient charts with a subluxated iris-fixated IOL after PK were retrospectively reviewed. Fourteen of the patients underwent surgery using a closed-chamber refixation technique. These patients were evaluated for visual outcome and surgical complications associated with the procedure. In 13 patients, postoperative follow-up was available. In all 13 cases, the fixated IOL appeared stable and remained well positioned during a follow-up period of 56 months (range, 6-122). All patients (100%) achieved improved uncorrected visual acuity. The postoperative visual acuity ranged from 20/20 to 20/100 with a mean of 20/40. Vitreous hemorrhage occurred in 1 patient, and an additional patient required a second surgery using the same technique. Both of these patients did well with a final visual acuity of 20/40 and 20/50, respectively. Subluxation of iris-fixated IOL after PK can occur as a postoperative complication. The technique that we herein describe enables secure refixation of subluxated IOLs and yields favorable long-term results.

  18. High-grade spondylolisthesis: gradual reduction using Magerl's external fixator followed by circumferential fusion technique and long-term results.

    Science.gov (United States)

    Karampalis, Christos; Grevitt, Michael; Shafafy, Masood; Webb, John

    2012-05-01

    To report the results of a cohort of patients treated with this technique high lighting radiological and functional outcomes, discussing also benefits arising from a gradual reduction procedure compared with other techniques. We evaluated nine patients who have undergone high-grade listhesis reduction and circumferential fusion at our institution from 1988 to 2006. Average length of follow-up was 11 years (5-19). Functional outcomes and radiological measurements were recorded and reported. Slip magnitude was reduced by an average of 2.9 grades (Meyerding classification). Slip angle improved by an average of 66% (p = 0.0001), lumbosacral angle by 47% (p = 0.0002), sacral rotation by 51% (p = 0.0068) and sacral inclination by 47% (p = 0.0055). At the latest follow-up 88.9% had achieved solid fusion. Post-operative 10-point Visual Analogue Score (VAS) for back pain had improved by 70% (p Average postoperative Oswestry Disability Index for all patients was 8% (range 0-16%) and that for Low Back Outcome Scores was 56.6 (range 44-70). All components of Short Form 36 Health Survey were greater than 80%. Overall patients' expectations were met in 100%. This is an effective and safe technique which addresses the lumbosacral kyphosis and cosmetic deformity without the neurological complications which accompany other reduction and fusion techniques for high-grade spondylolisthesis.

  19. Validation Techniques of the Intern Models for Credit Risk

    Directory of Open Access Journals (Sweden)

    Bogdan Moinescu

    2006-11-01

    Full Text Available The new own funds adequacy device, officialy named “ International Convergence of Capital Measurement and Capital Standards”, describes the most important benchmark framework for micro-prudential supervision at the moment. The publication of the final text in June 2004, after five years of deliberations, represents the result of multiple analyses and comments provided by all interested parties, banking supervision authorities, associations and credit institutions. Provided the development of complex methodologies of risk measurement and management, on a large scale, by credit institutions, simple and static rules of the first accord have become less and less relevant during the last years. And so, the need of setting up a own funds adequacy framework which is much more risk sensitive and provides incentives to credit institutions on what concerns the improvement of risk measurement and management systems was met by approval of the Basel II Accord, which will, therefore, lead to the strengthening of financial stability. The revisal of the Accord was mainly focused on the increase of risk analysis and internal measurement and the changes made to their estimation allow banks to create their own methodological framework to calculate capital requirements (also considering each credit institution’ risk appetite.

  20. Results of the benchmark for blade structural models, part A

    DEFF Research Database (Denmark)

    Lekou, D.J.; Chortis, D.; Belen Fariñas, A.

    2013-01-01

    A benchmark on structural design methods for blades was performed within the InnWind.Eu project under WP2 “Lightweight Rotor” Task 2.2 “Lightweight structural design”. The present document is describes the results of the comparison simulation runs that were performed by the partners involved within...... Task 2.2 of the InnWind.Eu project. The benchmark is based on the reference wind