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Sample records for modeling sem method

  1. SEM-microphotogrammetry, a new take on an old method for generating high-resolution 3D models from SEM images.

    Science.gov (United States)

    Ball, A D; Job, P A; Walker, A E L

    2017-08-01

    The method we present here uses a scanning electron microscope programmed via macros to automatically capture dozens of images at suitable angles to generate accurate, detailed three-dimensional (3D) surface models with micron-scale resolution. We demonstrate that it is possible to use these Scanning Electron Microscope (SEM) images in conjunction with commercially available software originally developed for photogrammetry reconstructions from Digital Single Lens Reflex (DSLR) cameras and to reconstruct 3D models of the specimen. These 3D models can then be exported as polygon meshes and eventually 3D printed. This technique offers the potential to obtain data suitable to reconstruct very tiny features (e.g. diatoms, butterfly scales and mineral fabrics) at nanometre resolution. Ultimately, we foresee this as being a useful tool for better understanding spatial relationships at very high resolution. However, our motivation is also to use it to produce 3D models to be used in public outreach events and exhibitions, especially for the blind or partially sighted. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  2. A new method of measuring stock market manipulation through structural equation modeling (SEM)

    OpenAIRE

    Maxim, Maruf Rahman; Ashif, Abu Sadat Muhammad

    2017-01-01

    This paper proposes a new model of measuring a latent variable, stock market manipulation. The model bears close resemblance with the literature on economic well-being. It interprets the manipulation of a stock as a latent variable, in the form of a multiple indicators and multiple causes (MIMIC) model. This approach exploits systematic relations between various indicators of manipulation and between manipulation and multiple causes, which allows it to identify the determinants of manipulatio...

  3. Structuring Consumer Preferences with the SEM Method

    OpenAIRE

    Rosa, Franco

    2002-01-01

    Structuring preferences has been developed with econometric models using functional flexible parametric form and the exploring the perceptions about expressed and latent needs using different multivariate approaches. Purpose of this research is to explore the demand for a new drink using the mean-end chain (MEC) theory and multivariate SEM procedure. The first part is dedicated to description of specialty foods for their capacity to create new niche markets. The MEC theory is introduced to ex...

  4. AxiSEM3D: a new fast method for global wave propagation in 3-D Earth models with undulating discontinuities

    Science.gov (United States)

    Leng, K.; Nissen-Meyer, T.; van Driel, M.; Al-Attar, D.

    2016-12-01

    We present a new, computationally efficient numerical method to simulate global seismic wave propagation in realistic 3-D Earth models with laterally heterogeneous media and finite boundary perturbations. Our method is a hybrid of pseudo-spectral and spectral element methods (SEM). We characterize the azimuthal dependence of 3-D wavefields in terms of Fourier series, such that the 3-D equations of motion reduce to an algebraic system of coupled 2-D meridional equations, which can be solved by a 2-D spectral element method (based on www.axisem.info). Computational efficiency of our method stems from lateral smoothness of global Earth models (with respect to wavelength) as well as axial singularity of seismic point sources, which jointly confine the Fourier modes of wavefields to a few lower orders. All boundary perturbations that violate geometric spherical symmetry, including Earth's ellipticity, topography and bathymetry, undulations of internal discontinuities such as Moho and CMB, are uniformly considered by means of a Particle Relabeling Transformation.The MPI-based high performance C++ code AxiSEM3D, is now available for forward simulations upon 3-D Earth models with fluid outer core, ellipticity, and both mantle and crustal structures. We show novel benchmarks for global wave solutions in 3-D mantle structures between our method and an independent, fully discretized 3-D SEM with remarkable agreement. Performance comparisons are carried out on three state-of-the-art tomography models, with seismic period going down to 5s. It is shown that our method runs up to two orders of magnitude faster than the 3-D SEM for such settings, and such computational advantage scales favourably with seismic frequency. By examining wavefields passing through hypothetical Gaussian plumes of varying sharpness, we identify in model-wavelength space the limits where our method may lose its advantage.

  5. semPLS: Structural Equation Modeling Using Partial Least Squares

    Directory of Open Access Journals (Sweden)

    Armin Monecke

    2012-05-01

    Full Text Available Structural equation models (SEM are very popular in many disciplines. The partial least squares (PLS approach to SEM offers an alternative to covariance-based SEM, which is especially suited for situations when data is not normally distributed. PLS path modelling is referred to as soft-modeling-technique with minimum demands regarding mea- surement scales, sample sizes and residual distributions. The semPLS package provides the capability to estimate PLS path models within the R programming environment. Different setups for the estimation of factor scores can be used. Furthermore it contains modular methods for computation of bootstrap confidence intervals, model parameters and several quality indices. Various plot functions help to evaluate the model. The well known mobile phone dataset from marketing research is used to demonstrate the features of the package.

  6. An electron moiré method for a common SEM

    Institute of Scientific and Technical Information of China (English)

    Y.M.Xing; S.Kishimoto; Y.R.Zhao

    2006-01-01

    In the electron moiré method,a high-frequency grating is used to measure microscopic deformation,which promises significant potential applications for the method in the microscopic analysis of materials.However,a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope (SEM).Because only a few SEMs used in the material science studies are equipped with this device,the use of the electron moiré method is limited.In this study,an electron moiré method for a common SEM without the beam control device is presented.A grating based on a multi-scanning concept is fabricated in any observing mode.A real-time moiré pattern can also be generated in the SEM or an optical filtering system.Without the beam control device being a prerequisite,the electron moiré method can be more widely used.The experimental results from three different types of SEMS show that high quality gratings with uniform lines and less pitch error can be fabricated by this method,and moiré patterns can also be correctly generated.

  7. Design and Use of the Simple Event Model (SEM)

    NARCIS (Netherlands)

    van Hage, W.R.; Malaisé, V.; Segers, R.H.; Hollink, L.

    2011-01-01

    Events have become central elements in the representation of data from domains such as history, cultural heritage, multimedia and geography. The Simple Event Model (SEM) is created to model events in these various domains, without making assumptions about the domain-specific vocabularies used. SEM

  8. Model improvements to simulate charging in SEM

    Science.gov (United States)

    Arat, K. T.; Klimpel, T.; Hagen, C. W.

    2018-03-01

    Charging of insulators is a complex phenomenon to simulate since the accuracy of the simulations is very sensitive to the interaction of electrons with matter and electric fields. In this study, we report model improvements for a previously developed Monte-Carlo simulator to more accurately simulate samples that charge. The improvements include both modelling of low energy electron scattering and charging of insulators. The new first-principle scattering models provide a more realistic charge distribution cloud in the material, and a better match between non-charging simulations and experimental results. Improvements on charging models mainly focus on redistribution of the charge carriers in the material with an induced conductivity (EBIC) and a breakdown model, leading to a smoother distribution of the charges. Combined with a more accurate tracing of low energy electrons in the electric field, we managed to reproduce the dynamically changing charging contrast due to an induced positive surface potential.

  9. A simplified method for scanning electron microscopy (SEM) autoradiography

    International Nuclear Information System (INIS)

    Shahar, A.; Lasher, R.

    1980-01-01

    The combination of autoradiography with SEM provides a valuable tool for the study of labeled biological materials, but the previously described methods are complicated because they call first for the removal of gelatin from the film emulsion and this is then followed by deposition of gold vapor on the specimen. The authors describe a much simpler method which can easily be adapted to routine examination of cell cultures. In this method, gelatin is not removed; the film is coated with vaporized carbon only. This procedure permits visualization of both cellular image and distribution of silver grains. (Auth.)

  10. Continuous time modeling of panel data by means of SEM

    NARCIS (Netherlands)

    Oud, J.H.L.; Delsing, M.J.M.H.; Montfort, C.A.G.M.; Oud, J.H.L.; Satorra, A.

    2010-01-01

    After a brief history of continuous time modeling and its implementation in panel analysis by means of structural equation modeling (SEM), the problems of discrete time modeling are discussed in detail. This is done by means of the popular cross-lagged panel design. Next, the exact discrete model

  11. CD-SEM real time bias correction using reference metrology based modeling

    Science.gov (United States)

    Ukraintsev, V.; Banke, W.; Zagorodnev, G.; Archie, C.; Rana, N.; Pavlovsky, V.; Smirnov, V.; Briginas, I.; Katnani, A.; Vaid, A.

    2018-03-01

    Accuracy of patterning impacts yield, IC performance and technology time to market. Accuracy of patterning relies on optical proximity correction (OPC) models built using CD-SEM inputs and intra die critical dimension (CD) control based on CD-SEM. Sub-nanometer measurement uncertainty (MU) of CD-SEM is required for current technologies. Reported design and process related bias variation of CD-SEM is in the range of several nanometers. Reference metrology and numerical modeling are used to correct SEM. Both methods are slow to be used for real time bias correction. We report on real time CD-SEM bias correction using empirical models based on reference metrology (RM) data. Significant amount of currently untapped information (sidewall angle, corner rounding, etc.) is obtainable from SEM waveforms. Using additional RM information provided for specific technology (design rules, materials, processes) CD extraction algorithms can be pre-built and then used in real time for accurate CD extraction from regular CD-SEM images. The art and challenge of SEM modeling is in finding robust correlation between SEM waveform features and bias of CD-SEM as well as in minimizing RM inputs needed to create accurate (within the design and process space) model. The new approach was applied to improve CD-SEM accuracy of 45 nm GATE and 32 nm MET1 OPC 1D models. In both cases MU of the state of the art CD-SEM has been improved by 3x and reduced to a nanometer level. Similar approach can be applied to 2D (end of line, contours, etc.) and 3D (sidewall angle, corner rounding, etc.) cases.

  12. SEM based CARMA time series modeling for arbitrary N

    NARCIS (Netherlands)

    Oud, J.H.L.; Völkle, M.C.; Driver, C.C.

    2018-01-01

    This article explains in detail the state space specification and estimation of first and higher-order autoregressive moving-average models in continuous time (CARMA) in an extended structural equation modeling (SEM) context for N = 1 as well as N > 1. To illustrate the approach, simulations will be

  13. What Determines Lean Manufacturing Implementation? A CB-SEM Model

    Directory of Open Access Journals (Sweden)

    Tan Ching Ng

    2018-02-01

    Full Text Available This research aims to ascertain the determinants of effective Lean Manufacturing (LM. In this research, Covariance-based Structural Equation Modeling (CB-SEM analysis will be used in order to analyze the determinants. Through CB-SEM analysis, the significant key determinants can be determined and the direct relationships among determinants can be analyzed. Thus, the findings of this research can act as guidelines for achievement of LM effectiveness, not only providing necessary steps for successful implementation of lean, but also helping lean companies to achieve higher level of lean cost and time savings.

  14. From patterns to causal understanding: Structural equation modeling (SEM) in soil ecology

    Science.gov (United States)

    Eisenhauer, Nico; Powell, Jeff R; Grace, James B.; Bowker, Matthew A.

    2015-01-01

    In this perspectives paper we highlight a heretofore underused statistical method in soil ecological research, structural equation modeling (SEM). SEM is commonly used in the general ecological literature to develop causal understanding from observational data, but has been more slowly adopted by soil ecologists. We provide some basic information on the many advantages and possibilities associated with using SEM and provide some examples of how SEM can be used by soil ecologists to shift focus from describing patterns to developing causal understanding and inspiring new types of experimental tests. SEM is a promising tool to aid the growth of soil ecology as a discipline, particularly by supporting research that is increasingly hypothesis-driven and interdisciplinary, thus shining light into the black box of interactions belowground.

  15. Maximum Likelihood Dynamic Factor Modeling for Arbitrary "N" and "T" Using SEM

    Science.gov (United States)

    Voelkle, Manuel C.; Oud, Johan H. L.; von Oertzen, Timo; Lindenberger, Ulman

    2012-01-01

    This article has 3 objectives that build on each other. First, we demonstrate how to obtain maximum likelihood estimates for dynamic factor models (the direct autoregressive factor score model) with arbitrary "T" and "N" by means of structural equation modeling (SEM) and compare the approach to existing methods. Second, we go beyond standard time…

  16. Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A. [Electromagnetic cluster, Universiti Teknologi Petronas, 31750 Tronoh, Perak (Malaysia)

    2012-09-26

    The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.

  17. Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances

    International Nuclear Information System (INIS)

    Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A.

    2012-01-01

    The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.

  18. Evaluation of bone formation in calcium phosphate scaffolds with μCT-method validation using SEM.

    Science.gov (United States)

    Lewin, S; Barba, A; Persson, C; Franch, J; Ginebra, M-P; Öhman-Mägi, C

    2017-10-05

    There is a plethora of calcium phosphate (CaP) scaffolds used as synthetic substitutes to bone grafts. The scaffold performance is often evaluated from the quantity of bone formed within or in direct contact with the scaffold. Micro-computed tomography (μCT) allows three-dimensional evaluation of bone formation inside scaffolds. However, the almost identical x-ray attenuation of CaP and bone obtrude the separation of these phases in μCT images. Commonly, segmentation of bone in μCT images is based on gray scale intensity, with manually determined global thresholds. However, image analysis methods, and methods for manual thresholding in particular, lack standardization and may consequently suffer from subjectivity. The aim of the present study was to provide a methodological framework for addressing these issues. Bone formation in two types of CaP scaffold architectures (foamed and robocast), obtained from a larger animal study (a 12 week canine animal model) was evaluated by μCT. In addition, cross-sectional scanning electron microscopy (SEM) images were acquired as references to determine thresholds and to validate the result. μCT datasets were registered to the corresponding SEM reference. Global thresholds were then determined by quantitatively correlating the different area fractions in the μCT image, towards the area fractions in the corresponding SEM image. For comparison, area fractions were also quantified using global thresholds determined manually by two different approaches. In the validation the manually determined thresholds resulted in large average errors in area fraction (up to 17%), whereas for the evaluation using SEM references, the errors were estimated to be less than 3%. Furthermore, it was found that basing the thresholds on one single SEM reference gave lower errors than determining them manually. This study provides an objective, robust and less error prone method to determine global thresholds for the evaluation of bone formation in

  19. SEM Based CARMA Time Series Modeling for Arbitrary N.

    Science.gov (United States)

    Oud, Johan H L; Voelkle, Manuel C; Driver, Charles C

    2018-01-01

    This article explains in detail the state space specification and estimation of first and higher-order autoregressive moving-average models in continuous time (CARMA) in an extended structural equation modeling (SEM) context for N = 1 as well as N > 1. To illustrate the approach, simulations will be presented in which a single panel model (T = 41 time points) is estimated for a sample of N = 1,000 individuals as well as for samples of N = 100 and N = 50 individuals, followed by estimating 100 separate models for each of the one-hundred N = 1 cases in the N = 100 sample. Furthermore, we will demonstrate how to test the difference between the full panel model and each N = 1 model by means of a subject-group-reproducibility test. Finally, the proposed analyses will be applied in an empirical example, in which the relationships between mood at work and mood at home are studied in a sample of N = 55 women. All analyses are carried out by ctsem, an R-package for continuous time modeling, interfacing to OpenMx.

  20. A Proposal on the Quantitative Homogeneity Analysis Method of SEM Images for Material Inspections

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Song Hyun; Kim, Jong Woo; Shin, Chang Ho [Hanyang University, Seoul (Korea, Republic of); Choi, Jung-Hoon; Cho, In-Hak; Park, Hwan Seo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    A scanning electron microscope (SEM) is a method to inspect the surface microstructure of materials. The SEM uses electron beams for imaging high magnifications of material surfaces; therefore, various chemical analyses can be performed from the SEM images. Therefore, it is widely used for the material inspection, chemical characteristic analysis, and biological analysis. For the nuclear criticality analysis field, it is an important parameter to check the homogeneity of the compound material for using it in the nuclear system. In our previous study, the SEM was tried to use for the homogeneity analysis of the materials. In this study, a quantitative homogeneity analysis method of SEM images is proposed for the material inspections. The method is based on the stochastic analysis method with the information of the grayscales of the SEM images.

  1. A Proposal on the Quantitative Homogeneity Analysis Method of SEM Images for Material Inspections

    International Nuclear Information System (INIS)

    Kim, Song Hyun; Kim, Jong Woo; Shin, Chang Ho; Choi, Jung-Hoon; Cho, In-Hak; Park, Hwan Seo

    2015-01-01

    A scanning electron microscope (SEM) is a method to inspect the surface microstructure of materials. The SEM uses electron beams for imaging high magnifications of material surfaces; therefore, various chemical analyses can be performed from the SEM images. Therefore, it is widely used for the material inspection, chemical characteristic analysis, and biological analysis. For the nuclear criticality analysis field, it is an important parameter to check the homogeneity of the compound material for using it in the nuclear system. In our previous study, the SEM was tried to use for the homogeneity analysis of the materials. In this study, a quantitative homogeneity analysis method of SEM images is proposed for the material inspections. The method is based on the stochastic analysis method with the information of the grayscales of the SEM images

  2. AxiSEM3D: broadband seismic wavefields in 3-D aspherical Earth models

    Science.gov (United States)

    Leng, K.; Nissen-Meyer, T.; Zad, K. H.; van Driel, M.; Al-Attar, D.

    2017-12-01

    Seismology is the primary tool for data-informed inference of Earth structure and dynamics. Simulating seismic wave propagation at a global scale is fundamental to seismology, but remains as one of most challenging problems in scientific computing, because of both the multiscale nature of Earth's interior and the observable frequency band of seismic data. We present a novel numerical method to simulate global seismic wave propagation in realistic 3-D Earth models. Our method, named AxiSEM3D, is a hybrid of spectral element method and pseudospectral method. It reduces the azimuthal dimension of wavefields by means of a global Fourier series parameterization, of which the number of terms can be locally adapted to the inherent azimuthal smoothness of the wavefields. AxiSEM3D allows not only for material heterogeneities, such as velocity, density, anisotropy and attenuation, but also for finite undulations on radial discontinuities, both solid-solid and solid-fluid, and thereby a variety of aspherical Earth features such as ellipticity, topography, variable crustal thickness, and core-mantle boundary topography. Such interface undulations are equivalently interpreted as material perturbations of the contiguous media, based on the "particle relabelling transformation". Efficiency comparisons show that AxiSEM3D can be 1 to 3 orders of magnitude faster than conventional 3-D methods, with the speedup increasing with simulation frequency and decreasing with model complexity, but for all realistic structures the speedup remains at least one order of magnitude. The observable frequency range of global seismic data (up to 1 Hz) has been covered for wavefield modelling upon a 3-D Earth model with reasonable computing resources. We show an application of surface wave modelling within a state-of-the-art global crustal model (Crust1.0), with the synthetics compared to real data. The high-performance C++ code is released at github.com/AxiSEM3D/AxiSEM3D.

  3. The advancement of the built environment research through employment of structural equation modeling (SEM)

    Science.gov (United States)

    Wasilah, S.; Fahmyddin, T.

    2018-03-01

    The employment of structural equation modeling (SEM) in research has taken an increasing attention in among researchers in built environment. There is a gap to understand the attributes, application, and importance of this approach in data analysis in built environment study. This paper intends to provide fundamental comprehension of SEM method in data analysis, unveiling attributes, employment and significance and bestow cases to assess associations amongst variables and constructs. The study uses some main literature to grasp the essence of SEM regarding with built environment research. The better acknowledgment of this analytical tool may assist the researcher in the built environment to analyze data under complex research questions and to test multivariate models in a single study.

  4. Tillandsia stricta Sol (Bromeliaceae) leaves as monitors of airborne particulate matter-A comparative SEM methods evaluation: Unveiling an accurate and odd HP-SEM method.

    Science.gov (United States)

    de Oliveira, Martha Lima; de Melo, Edésio José Tenório; Miguens, Flávio Costa

    2016-09-01

    Airborne particulate matter (PM) has been included among the most important air pollutants by governmental environment agencies and academy researchers. The use of terrestrial plants for monitoring PM has been widely accepted, particularly when it is coupled with SEM/EDS. Herein, Tillandsia stricta leaves were used as monitors of PM, focusing on a comparative evaluation of Environmental SEM (ESEM) and High-Pressure SEM (HPSEM). In addition, specimens air-dried at formaldehyde atmosphere (AD/FA) were introduced as an SEM procedure. Hydrated specimen observation by ESEM was the best way to get information from T. stricta leaves. If any artifacts were introduced by AD/FA, they were indiscernible from those caused by CPD. Leaf anatomy was always well preserved. PM density was determined on adaxial and abaxial leaf epidermis for each of the SEM proceedings. When compared with ESEM, particle extraction varied from 0 to 20% in air-dried leaves while 23-78% of particles deposited on leaves surfaces were extracted by CPD procedures. ESEM was obviously the best choice over other methods but morphological artifacts increased in function of operation time while HPSEM operation time was without limit. AD/FA avoided the shrinkage observed in the air-dried leaves and particle extraction was low when compared with CPD. Structural and particle density results suggest AD/FA as an important methodological approach to air pollution biomonitoring that can be widely used in all electron microscopy labs. Otherwise, previous PM assessments using terrestrial plants as biomonitors and performed by conventional SEM could have underestimated airborne particulate matter concentration. © 2016 Wiley Periodicals, Inc.

  5. A brief discussion about image quality and SEM methods for quantitative fractography of polymer composites.

    Science.gov (United States)

    Hein, L R O; Campos, K A; Caltabiano, P C R O; Kostov, K G

    2013-01-01

    The methodology for fracture analysis of polymeric composites with scanning electron microscopes (SEM) is still under discussion. Many authors prefer to use sputter coating with a conductive material instead of applying low-voltage (LV) or variable-pressure (VP) methods, which preserves the original surfaces. The present work examines the effects of sputter coating with 25 nm of gold on the topography of carbon-epoxy composites fracture surfaces, using an atomic force microscope. Also, the influence of SEM imaging parameters on fractal measurements is evaluated for the VP-SEM and LV-SEM methods. It was observed that topographic measurements were not significantly affected by the gold coating at tested scale. Moreover, changes on SEM setup leads to nonlinear outcome on texture parameters, such as fractal dimension and entropy values. For VP-SEM or LV-SEM, fractal dimension and entropy values did not present any evident relation with image quality parameters, but the resolution must be optimized with imaging setup, accompanied by charge neutralization. © Wiley Periodicals, Inc.

  6. CUFE at SemEval-2016 Task 4: A Gated Recurrent Model for Sentiment Classification

    KAUST Repository

    Nabil, Mahmoud

    2016-06-16

    In this paper we describe a deep learning system that has been built for SemEval 2016 Task4 (Subtask A and B). In this work we trained a Gated Recurrent Unit (GRU) neural network model on top of two sets of word embeddings: (a) general word embeddings generated from unsupervised neural language model; and (b) task specific word embeddings generated from supervised neural language model that was trained to classify tweets into positive and negative categories. We also added a method for analyzing and splitting multi-words hashtags and appending them to the tweet body before feeding it to our model. Our models achieved 0.58 F1-measure for Subtask A (ranked 12/34) and 0.679 Recall for Subtask B (ranked 12/19).

  7. Effects of Missing Data Methods in SEM under Conditions of Incomplete and Nonnormal Data

    Science.gov (United States)

    Li, Jian; Lomax, Richard G.

    2017-01-01

    Using Monte Carlo simulations, this research examined the performance of four missing data methods in SEM under different multivariate distributional conditions. The effects of four independent variables (sample size, missing proportion, distribution shape, and factor loading magnitude) were investigated on six outcome variables: convergence rate,…

  8. A hybrid 3D SEM reconstruction method optimized for complex geologic material surfaces.

    Science.gov (United States)

    Yan, Shang; Adegbule, Aderonke; Kibbey, Tohren C G

    2017-08-01

    Reconstruction methods are widely used to extract three-dimensional information from scanning electron microscope (SEM) images. This paper presents a new hybrid reconstruction method that combines stereoscopic reconstruction with shape-from-shading calculations to generate highly-detailed elevation maps from SEM image pairs. The method makes use of an imaged glass sphere to determine the quantitative relationship between observed intensity and angles between the beam and surface normal, and the detector and surface normal. Two specific equations are derived to make use of image intensity information in creating the final elevation map. The equations are used together, one making use of intensities in the two images, the other making use of intensities within a single image. The method is specifically designed for SEM images captured with a single secondary electron detector, and is optimized to capture maximum detail from complex natural surfaces. The method is illustrated with a complex structured abrasive material, and a rough natural sand grain. Results show that the method is capable of capturing details such as angular surface features, varying surface roughness, and surface striations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. SEM Model Medical Solid Waste Hospital Management In Medan City

    Science.gov (United States)

    Simarmata, Verawaty; Pandia, Setiaty; Mawengkang, Herman

    2018-01-01

    In daily activities, hospitals, as one of the important health care unit, generate both medical solid waste and non-medical solid waste. The occurrence of medical solid waste could be from the results of treatment activities, such as, in the treatment room for a hospital inpatient, general clinic, a dental clinic, a mother and child clinic, laboratories and pharmacies. Most of the medical solid waste contains infectious and hazardous materials. Therefore it should be managed properly, otherwise it could be a source of new infectious for the community around the hospital as well as for health workers themselves. Efforts surveillance of various environmental factors need to be applied in accordance with the principles of sanitation focuses on environmental cleanliness. One of the efforts that need to be done in improving the quality of the environment is to undertake waste management activities, because with proper waste management is the most important in order to achieve an optimal degree of human health. Health development in Indonesian aims to achieve a future in which the Indonesian people live in a healthy environment, its people behave clean and healthy, able to reach quality health services, fair and equitable, so as to have optimal health status, health development paradigm anchored to the healthy. The healthy condition of the individual and society can be influenced by the environment. Poor environmental quality is a cause of various health problems. Efforts surveillance of various environmental factors need to be applied in accordance with the principles of sanitation focuses on environmental cleanliness. This paper proposes a model for managing the medical solid waste in hospitals in Medan city, in order to create healthy environment around hospitals.

  10. Understanding the Online : Jewellery Retail Market : an integrated model to conduct SEM

    OpenAIRE

    Wu, Yihong

    2013-01-01

    Research into e-commerce is becoming more and more popular; however the jewellery industry is somewhat special. There are very few studies having adapted a strategic marketing perspective on the online jewellery retail market. This study suggested an integrated online marketing strategy which focuses on the search engine marketing (SEM) approach. A detailed procedure of conducting search engine marketing (SEM) is introduced. Through the method of online questionnaires, with the help of soc...

  11. Evaluating Neighborhoods Livability in Nigeria: A Structural Equation Modelling (SEM Approach

    Directory of Open Access Journals (Sweden)

    Sule Abass Iyanda

    2018-01-01

    Full Text Available There is a growing concern about city livability around the world and of particular concern is the aspects of the person-environment relationship which encompasses many characteristics suffice to make a place livable. Extant literature provides livability dimensions such as housing unit characteristics, neighborhood facilities, economic vitality and safety environment. These livability dimensions as well as their attributes found in the extant literature have been reported to have high reliability measurement level. Although, various methods have been applied to examine relationships among the variables however structural equation modeling (SEM has been found more holistic as a modeling technique to understand and explain the relationships that may exist among variable measurements. Structural equation modeling simultaneously performs multivariate analysis including multiple regression, path and factor analysis in the cause-effect relationships between latent constructs. Therefore, this study investigates the key factors of livability of planned residential neighborhoods in Minna, Nigeria with the research objectives of – (a to study the livability level of the selected residential neighborhoods, (b to determine the dimensions and indicators which most influence the level of livability in the selected residential neighborhoods, and (c to reliably test the efficacy of structural equation modeling (SEM in the assessment of livability. The methodology adopted in this study includes- Data collection with the aid of structured questionnaire survey administered to the residents of the study area based on stratified random sampling. The data collected was analyzed with the aid of the Statistical Package for Social Sciences (SPSS 22.0 and AMOS 22.0 software for structural equation modeling (a second-order factor. The study revealed that livability as a second-order factor is indicated by economic vitality, safety environment, neighborhood facilities

  12. A Sandwich-Type Standard Error Estimator of SEM Models with Multivariate Time Series

    Science.gov (United States)

    Zhang, Guangjian; Chow, Sy-Miin; Ong, Anthony D.

    2011-01-01

    Structural equation models are increasingly used as a modeling tool for multivariate time series data in the social and behavioral sciences. Standard error estimators of SEM models, originally developed for independent data, require modifications to accommodate the fact that time series data are inherently dependent. In this article, we extend a…

  13. Prescriptive Statements and Educational Practice: What Can Structural Equation Modeling (SEM) Offer?

    Science.gov (United States)

    Martin, Andrew J.

    2011-01-01

    Longitudinal structural equation modeling (SEM) can be a basis for making prescriptive statements on educational practice and offers yields over "traditional" statistical techniques under the general linear model. The extent to which prescriptive statements can be made will rely on the appropriate accommodation of key elements of research design,…

  14. Adapted methods for scanning electron microscopy (SEM in assessment of human sperm morphology

    Directory of Open Access Journals (Sweden)

    Petra Nussdorfer

    2018-02-01

    Full Text Available Infertility is a widespread problem, and in some cases, the routine basic semen analysis is not sufficient to detect the cause of male infertility. The use of the scanning electron microscope (SEM could provide a detailed insight into spermatozoa morphology, but it requires specific sample preparation techniques. The purpose of this study was to select, adjust, and optimize a method for the preparation of spermatozoa samples prior to SEM analysis, and to establish the protocol required for its use in clinical practice. We examined sperm samples of 50 men. The samples were fixed with modified iso-osmolar aldehyde solution followed by osmium post-fixation. In the first method, dehydration of the cells and subsequent critical point drying (CPD were performed on a coverslip. In the second method, the samples were dehydrated in centrifuge tubes; hexamethyldisilazane (HMDS was used as a drying agent instead of CPD, and the samples were air-dried. The third procedure was based on a membrane filter. The samples were dehydrated and dried with HMDS in a Gooch crucible, continuously, without centrifugation or redispersion of the sample. Our results showed that the fixation with modified iso-osmolar aldehyde solution followed by osmium post-fixation, and combined with dehydration and CPD on a coverslip, is the most convenient procedure for SEM sample preparation. In the case of small-size samples or low sperm concentration, dehydration and drying with HMDS on the membrane filter enabled the best reliability, repeatability, and comparability of the results. The presented procedures are suitable for routine use, and they can be applied to confirm as well as to correct a diagnosis.

  15. Recent improvement of a FIB-SEM serial-sectioning method for precise 3D image reconstruction - application of the orthogonally-arranged FIB-SEM.

    Science.gov (United States)

    Hara, Toru

    2014-11-01

    plasma cleaner, many kinds of signals can be obtained simultaneously.jmicro;63/suppl_1/i5-a/DFU077F1F1DFU077F1Fig. 1.Schematic illustration described (a) a standard type arrangement, (b) an orthogonal type arrangement. Recent topics and Future prospectsWe have applied this instrument for wide area of microstructure analysis; Metals and Alloys, Semiconductor devices, Battery electrodes, Minerals, Biomaterials, and so on. In my presentation, I would like to introduce some of our application results and will discuss about future development of the methodology of a FIB-SEM serial sectioning. As the applied research field becomes wider, various requests for the method were arisen. However, most requests can be summarized as follows: observation of larger area, expansion of applicable sample, obtain many kind of information, linkage with other instruments. AcknowledgmentsThe instrument introduced in this work was installed at NIMS by a part of "Low-carbon research network Japan" funded by the MEXT,Japan. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Nanosilver microalgae biosynthesis: cell appearance based on SEM and EDX methods

    Science.gov (United States)

    Pancasakti Kusumaningrum, Hermin; Zainuri, Muhammad; Marhaendrajaya, Indras; Subagio, Agus

    2018-05-01

    Microbial contamination has caused public health problems in the world population. This problem has spurred the development of methods to overcome and prevent microbial invasion. The extensive use of antibiotics has facilitated the continued emergence and spread of resistant organisms. Synthesized of silver nanoparticle (AgNPs) on microalgae Chlorella pyrenoidosa offer environmentally safe antimicrobial agent. The present study is focused on the biosynthesis of AgNPs using microalgae C. pyrenoidosa. The research methods was conducted by insertion of nanosilver particle into microalgae cells with and without agitation to speed up the process of formation nanosilver microalgae. The formation of microalgae SNP was analyzes by UV-Vis spectrophotometer, Scanning Electron Micrograph (SEM) and Energy-dispersive X-ray spectroscopy (EDX) methods. The research result showed that nanosilver microalgae biosynthesis using the agitation treatment was exhibited better performance in particle insertion and cell stability, comparing with no agitation treatment. However, synthesis of nanosilver microalgae tend to reduce the cell size.

  17. Three-dimensional characterization of ODS ferritic steel using by FIB-SEM serial sectioning method.

    Science.gov (United States)

    Endo, T; Sugino, Y; Ohono, N; Ukai, S; Miyazaki, N; Wang, Y; Ohnuki, S

    2014-11-01

    Considerable attention has been paid to the research of the electron tomography due to determine the three-dimensional (3D) structure of materials [1]. One of the electron tomography techniques, focused ion beam/scanning electron microscopy (FIB-SEM) imaging has advantages of high resolutions (10 nm), large area observation (μm order) and simultaneous energy dispersive x- ray microanalysis (EDS)/ electron backscatter diffraction (EBSD) analysis. The purpose of this study, three-dimensional EBSD analysis of ODS ferritic steel which carried out cold work using FIB-SEM equipment was conducted, and it aimed at analyzing the microstructure obtained there. The zone annealing tests were conducted for ferritic steel [2,3], which were produced through mechanical alloying and hot-extrusion. After zone annealing, specimens were mechanically polished with #400∼4000 emery paper, 1 µm diamond paste and alumina colloidal silica. The serial sectioning and the 3D-electron backscattering diffraction (3D-EBSD) analysis were carried out. We made the micro pillar (30 x 30 x 15 µm). The EBSD measurements were carried out in each layer after serial sectioning at a step size and milling depth was 80 nm with 30 slices. After EBSD analysis, the series of cross-sectional images were aligned according to arbitrarily specified areas and then stacked up to form a volume. Consequently, we obtained the 3D-IPF maps for ODS ferritic steel. In this specimen, the {111} and {001} grains are layered by turns. In addition, the volume fraction value of both plane are similar. The aspect ratio increases with specimen depth. The 3D-EBSD mapping is useful to analysis of the bulk material since this method obtain many microstructure information, such a shape, volume and orientation of the crystal, grain boundary. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Estimation of pattern shape based on CD-SEM image by using MPPC method

    Science.gov (United States)

    Onozuka, T.; Ojima, Y.; Meessen, J.; Rijpers, B.

    2006-03-01

    This study demonstrates the MPPC (Multiple Parameters Profile Characterization) measurement method utilizing ArF photo resist patterns. MPPC is a technique for estimating the three dimensional profile of patterns which are imaged and measured on the CD-SEM (critical dimension scanning electron microscope). MPPC utilizes the secondary electron signal to calculate several indices including top CD, peak CD, top rounding, bottom footing, etc. This primary focused of this study is to understand the variations in pattern profile caused by changes in exposure condition. The results demonstrate the ability to extract pattern profile shape information by MPPC measurement that could not otherwise be detected by a conventional bottom CD measurement method. Furthermore, the results were compared to cross sectional images collected by STEM (scanning transmission electron microscope) to verify the accuracy of the MPPC technique. The peak CD results accurately estimate the pattern width when the sidewall angle of the feature is nearly vertical. Additionally, line edge roughness (LER) caused by pattern profile variations was evaluated utilizing MPPC. The results suggest that MPPC may be utilized to evaluate the roughness over the entire profile.

  19. Structural equation modeling methods and applications

    CERN Document Server

    Wang, Jichuan

    2012-01-01

    A reference guide for applications of SEM using Mplus Structural Equation Modeling: Applications Using Mplus is intended as both a teaching resource and a reference guide. Written in non-mathematical terms, this book focuses on the conceptual and practical aspects of Structural Equation Modeling (SEM). Basic concepts and examples of various SEM models are demonstrated along with recently developed advanced methods, such as mixture modeling and model-based power analysis and sample size estimate for SEM. The statistical modeling program, Mplus, is also featured and provides researchers with a

  20. SemFunSim: a new method for measuring disease similarity by integrating semantic and gene functional association.

    Directory of Open Access Journals (Sweden)

    Liang Cheng

    Full Text Available Measuring similarity between diseases plays an important role in disease-related molecular function research. Functional associations between disease-related genes and semantic associations between diseases are often used to identify pairs of similar diseases from different perspectives. Currently, it is still a challenge to exploit both of them to calculate disease similarity. Therefore, a new method (SemFunSim that integrates semantic and functional association is proposed to address the issue.SemFunSim is designed as follows. First of all, FunSim (Functional similarity is proposed to calculate disease similarity using disease-related gene sets in a weighted network of human gene function. Next, SemSim (Semantic Similarity is devised to calculate disease similarity using the relationship between two diseases from Disease Ontology. Finally, FunSim and SemSim are integrated to measure disease similarity.The high average AUC (area under the receiver operating characteristic curve (96.37% shows that SemFunSim achieves a high true positive rate and a low false positive rate. 79 of the top 100 pairs of similar diseases identified by SemFunSim are annotated in the Comparative Toxicogenomics Database (CTD as being targeted by the same therapeutic compounds, while other methods we compared could identify 35 or less such pairs among the top 100. Moreover, when using our method on diseases without annotated compounds in CTD, we could confirm many of our predicted candidate compounds from literature. This indicates that SemFunSim is an effective method for drug repositioning.

  1. The use of SEM/EDS method in mineralogical analysis of ordinary chondritic meteorite

    Directory of Open Access Journals (Sweden)

    Breda Mirtič

    2009-12-01

    Full Text Available The aim of this study was to evaluate the potential of scanning electron microscopy coupled with energy dispersiveX-ray spectroscopy (SEM/EDS for determination of mineral phases according to their stoichiometry and assessment of mineral composition of ordinary chondritic meteorite. For the purposes of this study, H3 type ordinary chondritic meteorite Abbott was selected. SEM/EDS allows identification and characterisation of mineralphases, whose size is below the resolution of an optical microscope. Mineral phases in chondrules and interstitial matrix were located in backscattered electron (BSE mode and were assessed from atomic proportions of constituent elements, obtained by the EDS analysis. SEM/EDS analyses of mineral phases showed that Abbott meteorite is characterised by Fe-rich (Fe, Ni-alloy kamacite, Fe-sulphide troilite or pyrrhotite, chromite, Mg-rich olivine, orthopyroxene bronzite or hypersthene, clinopyroxene Al-diopside, acid plagioclase oligoclase, accessory mineral chlorapatite and secondary minerals Fe-hydroxides (goethite or lepidocrocite. Results of semi-quantitative analyses confirmed that most of analysed mineralphases conform well to stoichiometric minerals with minor deviations of oxygen from stoichiometric proportions. Comparison between mineral phases in chondrules and interstitial matrix was also performed, however it showed no significant differences in elemental composition.Differences in chemical composition between minerals in interstitial matrix and chondrules are sometimes too small to be discernedby the SEM/EDS, therefore knowledge of SEM/EDS capabilities is important for correct interpretation of chondrite formation.

  2. PAT and SEM study of porous silicon formed by anodization methods

    International Nuclear Information System (INIS)

    Liu Jian; Wei Long; Wang Huiyao; Ma Chuangxin; Wang Baoyi

    2000-01-01

    The porous silicon formed by anodization of crystal silicon was studied by positron annihilation technique (PAT) and scanning electron microscopy (SEM). The PAT experiments showed that the mean life and vacancy defects increased with the increasing anodization time. While the intensities of the longest lifetime, several ns-tens ns (ortho-positronium) dropped down. Small single-crystal Si spheres with mean radius of a few μm were observed by SEM after anodization. Pits with mean radius of a few μm from the divorcement of single-crystal spheres were also observed after further anodization. The increases of vacancy defects might be that the extension of structures of porous silicon towards inner layer with anodization time and caused more vacancy defects in inner layer. The SEM observation presented another possibility of the increase of density of vacancy defects in surface layer induced by the change of structures

  3. SEM Anthology

    Science.gov (United States)

    Rodgers, Michelle; Zimar, Heather

    2004-01-01

    The "SEM Anthology" is a compilation of articles by more than 30 enrollment management professionals from a variety of institutions across the country. This collection, which has appeared in SEM Monthly over the past year, chronicles Strategic Enrollment Management efforts at campuses nationwide. The book illustrates the successes and challenges…

  4. Incorporating Latent Variables into Discrete Choice Models - A Simultaneous Estimation Approach Using SEM Software

    Directory of Open Access Journals (Sweden)

    Dirk Temme

    2008-12-01

    Full Text Available Integrated choice and latent variable (ICLV models represent a promising new class of models which merge classic choice models with the structural equation approach (SEM for latent variables. Despite their conceptual appeal, applications of ICLV models in marketing remain rare. We extend previous ICLV applications by first estimating a multinomial choice model and, second, by estimating hierarchical relations between latent variables. An empirical study on travel mode choice clearly demonstrates the value of ICLV models to enhance the understanding of choice processes. In addition to the usually studied directly observable variables such as travel time, we show how abstract motivations such as power and hedonism as well as attitudes such as a desire for flexibility impact on travel mode choice. Furthermore, we show that it is possible to estimate such a complex ICLV model with the widely available structural equation modeling package Mplus. This finding is likely to encourage more widespread application of this appealing model class in the marketing field.

  5. A Data Matrix Method for Improving the Quantification of Element Percentages of SEM/EDX Analysis

    Science.gov (United States)

    Lane, John

    2009-01-01

    A simple 2D M N matrix involving sample preparation enables the microanalyst to peer below the noise floor of element percentages reported by the SEM/EDX (scanning electron microscopy/ energy dispersive x-ray) analysis, thus yielding more meaningful data. Using the example of a 2 3 sample set, there are M = 2 concentration levels of the original mix under test: 10 percent ilmenite (90 percent silica) and 20 percent ilmenite (80 percent silica). For each of these M samples, N = 3 separate SEM/EDX samples were drawn. In this test, ilmenite is the element of interest. By plotting the linear trend of the M sample s known concentration versus the average of the N samples, a much higher resolution of elemental analysis can be performed. The resulting trend also shows how the noise is affecting the data, and at what point (of smaller concentrations) is it impractical to try to extract any further useful data.

  6. Methods for Additive Hydration Allowing Observation of Fully Hydrated State of Wet Samples in Environmental SEM

    Czech Academy of Sciences Publication Activity Database

    Neděla, Vilém

    2007-01-01

    Roč. 70, č. 2 (2007), s. 95-100 ISSN 1059-910X R&D Projects: GA ČR(CZ) GA102/05/0886; GA AV ČR KJB200650602 Institutional research plan: CEZ:AV0Z20650511 Keywords : agar * natural structure * biological specimens * environmental SEM Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.644, year: 2007

  7. A new method using Scanning Electron Microscopy (SEM) for preparation of anisopterous odonates.

    Science.gov (United States)

    Del Palacio, Alejandro; Sarmiento, Patricia Laura; Javier, Muzón

    2017-10-01

    Anisopterous odonate male's secondary genitalia is a complex of several structures, among them the vesica spermalis is the most informative with important specific characters. The observation of those characters, mostly of membranous nature, is difficult in the Scanning Electron Microscope due to dehydration and metallization processes. In this contribution, we discuss a new and low cost procedure for the observation of these characters in the SEM, compatible with the most common agents used for preserving specimens. © 2017 Wiley Periodicals, Inc.

  8. Projects Delay Factors of Saudi Arabia Construction Industry Using PLS-SEM Path Modelling Approach

    Directory of Open Access Journals (Sweden)

    Abdul Rahman Ismail

    2016-01-01

    Full Text Available This paper presents the development of PLS-SEM Path Model of delay factors of Saudi Arabia construction industry focussing on Mecca City. The model was developed and assessed using SmartPLS v3.0 software and it consists of 37 factors/manifests in 7 groups/independent variables and one dependent variable which is delay of the construction projects. The model was rigorously assessed at measurement and structural components and the outcomes found that the model has achieved the required threshold values. At structural level of the model, among the seven groups, the client and consultant group has the highest impact on construction delay with path coefficient β-value of 0.452 and the project management and contract administration group is having the least impact to the construction delay with β-value of 0.016. The overall model has moderate explaining power ability with R2 value of 0.197 for Saudi Arabia construction industry representation. This model will able to assist practitioners in Mecca city to pay more attention in risk analysis for potential construction delay.

  9. Defect window analysis by using SEM-contour based shape quantifying method for sub-20nm node production

    Science.gov (United States)

    Hibino, Daisuke; Hsu, Mingyi; Shindo, Hiroyuki; Izawa, Masayuki; Enomoto, Yuji; Lin, J. F.; Hu, J. R.

    2013-04-01

    The impact on yield loss due to systematic defect which remains after Optical Proximity Correction (OPC) modeling has increased, and achieving an acceptable yield has become more difficult in the leading technology beyond 20 nm node production. Furthermore Process-Window has become narrow because of the complexity of IC design and less process margin. In the past, the systematic defects have been inspected by human-eyes. However the judgment by human-eyes is sometime unstable and not accurate. Moreover an enormous amount of time and labor will have to be expended on the one-by-one judgment for several thousands of hot-spot defects. In order to overcome these difficulties and improve the yield and manufacturability, the automated system, which can quantify the shape difference with high accuracy and speed, is needed. Inspection points could be increased for getting higher yield, if the automated system achieves our goal. Defect Window Analysis (DWA) system by using high-precision-contour extraction from SEM image on real silicon and quantifying method which can calculate the difference between defect pattern and non-defect pattern automatically, which was developed by Hitachi High-Technologies, has been applied to the defect judgment instead of the judgment by human-eyes. The DWA result which describes process behavior might be feedback to design or OPC or mask. This new methodology and evaluation results will be presented in detail in this paper.

  10. Characterization of ash pond ashes from 3rd thermal power plant by SEM/EDX and XRD methods

    OpenAIRE

    A Minjigmaa; Ts Zolzaya; E Bayanjargal; B Davaabal; J Temuujin

    2014-01-01

      Coal combustion by products from ash pond of 3rdthermal power plant of Ulaanbaatar city have been collected in 2010 and 2013 years. The ash samples have been characterized by XRD, XRF and SEM-EDX methods in order to evaluate their chemical and mineralogical composition changes with disposed times. The mineralogical composition of ash varies with time though the chemical composition of the ashes were close each other. Possibly, inefficient operating condition of the TPS shows influence on th...

  11. ANALISA KUALITAS PELAYANAN BIOSKOP TERHADAP KEPUASAN DAN LOYALITAS PELANGGAN MENGGUNAKAN METODE STRUCTURAL EQUATION MODELING (SEM

    Directory of Open Access Journals (Sweden)

    Mochammad Edo Herokholiqi

    2018-04-01

    Full Text Available Bioskop XYZ adalah salah satu bioskop di wilayah kabupaten Sidoarjo yang mengutamakan kualitas dan kepuasan konsumen dengan terus memberikan layanan terbaik. Target pasar bioskop XYZ adalah masyarakat dengan ekonomi menengah ke bawah. Karena itu, pemilihan lokasi pendirian bioskop ini ialah pada tingkat kabupaten. Berkembangnya teknologi membuat persaingan bioskop semakin ketat baik dari pesaing, pembajakan film, harapan pelanggan meningkat serta bioskop yang masih dibutuhkan sebagai hiburan alternatif. Maka dari itu pengelola bioskop dituntut untuk lebih kreatif menarik pelanggan dengan berbagai cara antara lain dengan meningkatkan pelayanan. Untuk mengetahui pengaruh kualitas layanan terhadap kepuasan dan loyalitas pelanggan, serta pengaruh kepuasan pelanggan terhadap loyalitas pelanggan agar dapat memberikan beberapa usulan kepada bioskop berdasarkan hasil penelitian. Dalam meneliti hubungan variabel seperti permasalahan di atas digunakan metode Structural Equation Modeling (SEM. Hasil dari penelitian yang mengacu pada hasil uji hipotesa yang dilakukan menunjukkan bahwa variabel kualitas layanan berpengaruh terhadap kepuasan pelanggan, variabel kepuasan pelanggan berpengaruh terhadap loyalitas pelanggan namun variabel kualitas layanan tidak berpengaruh terhadap loyalitas pelanggan. Adapun indikator paling berpengaruh positif kualitas layananan yakni perhatian karyawan, pada kepuasan pelanggan yakni perasaan senang pelanggan dan pada variabel loyalitas pelanggan yakni merekomendasikan pada orang lain.

  12. Structural Equation Modeling (SEM) for Satisfaction and Dissatisfaction Ratings; Multiple Group Invariance Analysis across Scales with Different Response Format

    Science.gov (United States)

    Mazaheri, Mehrdad; Theuns, Peter

    2009-01-01

    The current study evaluates three hypothesized models on subjective well-being, comprising life domain ratings (LDR), overall satisfaction with life (OSWL), and overall dissatisfaction with life (ODWL), using structural equation modeling (SEM). A sample of 1,310 volunteering students, randomly assigned to six conditions, rated their overall life…

  13. Modeling Methods

    Science.gov (United States)

    Healy, Richard W.; Scanlon, Bridget R.

    2010-01-01

    Simulation models are widely used in all types of hydrologic studies, and many of these models can be used to estimate recharge. Models can provide important insight into the functioning of hydrologic systems by identifying factors that influence recharge. The predictive capability of models can be used to evaluate how changes in climate, water use, land use, and other factors may affect recharge rates. Most hydrological simulation models, including watershed models and groundwater-flow models, are based on some form of water-budget equation, so the material in this chapter is closely linked to that in Chapter 2. Empirical models that are not based on a water-budget equation have also been used for estimating recharge; these models generally take the form of simple estimation equations that define annual recharge as a function of precipitation and possibly other climatic data or watershed characteristics.Model complexity varies greatly. Some models are simple accounting models; others attempt to accurately represent the physics of water movement through each compartment of the hydrologic system. Some models provide estimates of recharge explicitly; for example, a model based on the Richards equation can simulate water movement from the soil surface through the unsaturated zone to the water table. Recharge estimates can be obtained indirectly from other models. For example, recharge is a parameter in groundwater-flow models that solve for hydraulic head (i.e. groundwater level). Recharge estimates can be obtained through a model calibration process in which recharge and other model parameter values are adjusted so that simulated water levels agree with measured water levels. The simulation that provides the closest agreement is called the best fit, and the recharge value used in that simulation is the model-generated estimate of recharge.

  14. Characterization of a millefiori glass find from Aquincum by SEM-EDX and micro-PIXE methods

    International Nuclear Information System (INIS)

    Uzonyi, I.; Csontos, K.; Verebes, A.; Cserhati, C.; Csedreki, L.; Kis-Varga, M.; Kiss, A.Z.

    2011-01-01

    Research has been focused on the analysis of archaeological glasses from the Roman age and medieval times. Study of ancient millefiori type glasses from the collection of Hungarian Museums has been started. A test measurement, carried out on a glass fragment supposedly part of a dish, was performed by SEM-EDX and micro-PIXE methods. Complementary analytical data were obtained for texture and composition. Results suggest that Roman and Mesopotamian techniques were used together. Our data contribute to data bases of millefiori glasses.

  15. Characterization of a millefiori glass find from Aquincum by SEM-EDX and micro-PIXE methods

    Energy Technology Data Exchange (ETDEWEB)

    Uzonyi, I., E-mail: uzonyi@atomki.hu [Institute of Nuclear Research of the Hungarian Academy of Sciences, H-4026 Debrecen, Bem ter 18/C (Hungary); Csontos, K.; Verebes, A. [Budapest History Museum, Aquincum Museum H-8211 Budapest, Zahony u. 4. (Hungary); Cserhati, C. [Department of Solid State Physics, University of Debrecen H-4032 Debrecen, Bem ter 18/B (Hungary); Csedreki, L.; Kis-Varga, M.; Kiss, A.Z. [Institute of Nuclear Research of the Hungarian Academy of Sciences, H-4026 Debrecen, Bem ter 18/C (Hungary)

    2011-10-15

    Research has been focused on the analysis of archaeological glasses from the Roman age and medieval times. Study of ancient millefiori type glasses from the collection of Hungarian Museums has been started. A test measurement, carried out on a glass fragment supposedly part of a dish, was performed by SEM-EDX and micro-PIXE methods. Complementary analytical data were obtained for texture and composition. Results suggest that Roman and Mesopotamian techniques were used together. Our data contribute to data bases of millefiori glasses.

  16. The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM.

    Science.gov (United States)

    Wilkerson, J Michael; Iantaffi, Alex; Smolenski, Derek J; Brady, Sonya S; Horvath, Keith J; Grey, Jeremy A; Rosser, B R Simon

    2012-01-01

    While the effects of sexually explicit media (SEM) on heterosexuals' sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM's experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs.

  17. Case Studies of Successful Schoolwide Enrichment Model-Reading (SEM-R) Classroom Implementations. Research Monograph Series. RM10204

    Science.gov (United States)

    Reis, Sally M.; Little, Catherine A.; Fogarty, Elizabeth; Housand, Angela M.; Housand, Brian C.; Sweeny, Sheelah M.; Eckert, Rebecca D.; Muller, Lisa M.

    2010-01-01

    The purpose of this qualitative study was to examine the scaling up of the Schoolwide Enrichment Model in Reading (SEM-R) in 11 elementary and middle schools in geographically diverse sites across the country. Qualitative comparative analysis was used in this study, with multiple data sources compiled into 11 in-depth school case studies…

  18. A SEM Model in Assessing the Effect of Convergent, Divergent and Logical Thinking on Students' Understanding of Chemical Phenomena

    Science.gov (United States)

    Stamovlasis, D.; Kypraios, N.; Papageorgiou, G.

    2015-01-01

    In this study, structural equation modeling (SEM) is applied to an instrument assessing students' understanding of chemical change. The instrument comprised items on understanding the structure of substances, chemical changes and their interpretation. The structural relationships among particular groups of items are investigated and analyzed using…

  19. Encapsulation of a Decision-Making Model to Optimize Supplier Selection via Structural Equation Modeling (SEM)

    Science.gov (United States)

    Sahul Hameed, Ruzanna; Thiruchelvam, Sivadass; Nasharuddin Mustapha, Kamal; Che Muda, Zakaria; Mat Husin, Norhayati; Ezanee Rusli, Mohd; Yong, Lee Choon; Ghazali, Azrul; Itam, Zarina; Hakimie, Hazlinda; Beddu, Salmia; Liyana Mohd Kamal, Nur

    2016-03-01

    This paper proposes a conceptual framework to compare criteria/factor that influence the supplier selection. A mixed methods approach comprising qualitative and quantitative survey will be used. The study intend to identify and define the metrics that key stakeholders at Public Works Department (PWD) believed should be used for supplier. The outcomes would foresee the possible initiatives to bring procurement in PWD to a strategic level. The results will provide a deeper understanding of drivers for supplier’s selection in the construction industry. The obtained output will benefit many parties involved in the supplier selection decision-making. The findings provides useful information and greater understanding of the perceptions that PWD executives hold regarding supplier selection and the extent to which these perceptions are consistent with findings from prior studies. The findings from this paper can be utilized as input for policy makers to outline any changes in the current procurement code of practice in order to enhance the degree of transparency and integrity in decision-making.

  20. An SEM Approach to Continuous Time Modeling of Panel Data: Relating Authoritarianism and Anomia

    Science.gov (United States)

    Voelkle, Manuel C.; Oud, Johan H. L.; Davidov, Eldad; Schmidt, Peter

    2012-01-01

    Panel studies, in which the same subjects are repeatedly observed at multiple time points, are among the most popular longitudinal designs in psychology. Meanwhile, there exists a wide range of different methods to analyze such data, with autoregressive and cross-lagged models being 2 of the most well known representatives. Unfortunately, in these…

  1. APLIKASI STRUCTURAL EQUATION MODEL (SEM DALAM PENENTUAN ALTERNATIF PENGELOLAAN LINGKUNGAN INDUSTRI KOMPONEN ALAT BERAT BERBASIS PARTISIPASI DAN KEMITRAAN MASYARAKAT

    Directory of Open Access Journals (Sweden)

    Budi Setyo Utomo

    2012-07-01

    Full Text Available As a company engaged in the industrial sector by producing certain components and localized in an industrial area, there will be an impact on the environment. These impacts can be positive in the form of employment, reducing dependence on imported heavy equipment, increase in foreign exchange due to reduced imports and increased exports, increased government revenue from taxes, public facilities improvement and supporting infrastructure, and opening up opportunities for other related industries. These impacts can also be negative in the form of environmental degradation such as noise disturbance, dust, and micro climate change, and changes in social and cultural conditions surrounding the industry. Data analysis was performed descriptively and with the Structural Equation Model (SEM. SEM is a multivariate statistical technique which is a combination of factor analysis and regression analysis (correlation, which aims to test the connections between existing variables in a model, whether it is between the indicator with the construct, or the connections between constructs. SEM model consists of two parts, which is the latent variable model and the observed variable model. In contrast to ordinary regression linking the causality between the observed variables, it is also possible in SEM to identify the causality between latent variables. The results of SEM analysis showed that the developed model has a fairly high level of validity that is shown by the minimum fit chi-square value of 93.15 (P = 0.00029. Based on said model, it shows that the company's performance in waste management is largely determined by employee integrity and objectivity of the new employees followed later by the independence of the employees in waste management. The most important factor that determines the employee integrity in waste management in the model is honesty, individual wisdom, and a sense of responsibility. The most important factor in the employee objectivity

  2. Characterization of ash pond ashes from 3rd thermal power plant by SEM/EDX and XRD methods

    Directory of Open Access Journals (Sweden)

    A Minjigmaa

    2014-10-01

    Full Text Available   Coal combustion by products from ash pond of 3rdthermal power plant of Ulaanbaatar city have been collected in 2010 and 2013 years. The ash samples have been characterized by XRD, XRF and SEM-EDX methods in order to evaluate their chemical and mineralogical composition changes with disposed times. The mineralogical composition of ash varies with time though the chemical composition of the ashes were close each other. Possibly, inefficient operating condition of the TPS shows influence on the mineralogical composition.DOI: http://dx.doi.org/10.5564/mjc.v14i0.201Mongolian Journal of Chemistry 14 (40, 2013, p61-65

  3. Multi Scale Finite Element Analyses By Using SEM-EBSD Crystallographic Modeling and Parallel Computing

    International Nuclear Information System (INIS)

    Nakamachi, Eiji

    2005-01-01

    A crystallographic homogenization procedure is introduced to the conventional static-explicit and dynamic-explicit finite element formulation to develop a multi scale - double scale - analysis code to predict the plastic strain induced texture evolution, yield loci and formability of sheet metal. The double-scale structure consists of a crystal aggregation - micro-structure - and a macroscopic elastic plastic continuum. At first, we measure crystal morphologies by using SEM-EBSD apparatus, and define a unit cell of micro structure, which satisfy the periodicity condition in the real scale of polycrystal. Next, this crystallographic homogenization FE code is applied to 3N pure-iron and 'Benchmark' aluminum A6022 polycrystal sheets. It reveals that the initial crystal orientation distribution - the texture - affects very much to a plastic strain induced texture and anisotropic hardening evolutions and sheet deformation. Since, the multi-scale finite element analysis requires a large computation time, a parallel computing technique by using PC cluster is developed for a quick calculation. In this parallelization scheme, a dynamic workload balancing technique is introduced for quick and efficient calculations

  4. Development and application of loop-mediated isothermal amplification methods targeting the seM gene for detection of Streptococcus equi subsp. equi.

    Science.gov (United States)

    Hobo, Seiji; Niwa, Hidekazu; Oku, Kazuomi

    2012-03-01

    Loop-mediated isothermal amplification (LAMP) constitutes a potentially valuable diagnostic tool for rapid diagnosis of contagious diseases. In this study, we developed a novel LAMP method (seM-LAMP) to detect the seM gene of Streptococcus equi subsp. equi (S. equi), the causative agent of strangles in equids. The seM-LAMP successfully amplified the target sequence of the seM gene at 63°C within 60 min. The sensitivity of the seM-LAMP was slightly lower than the 2nd reaction of the seM semi-nested PCR. To evaluate the species specificity of the seM-LAMP, we tested 100 S. equi and 189 non-S. equi strains. Significant amplification of the DNA originating from S. equi was observed within 60 min incubation, but no amplification of non-S. equi DNA occurred. The results were identical to those of seM semi-nested PCR. To investigate the clinical usefulness of the methods, the seM-LAMP and the seM semi-nested PCR were used to screen 590 nasal swabs obtained during an outbreak of strangles. Both methods showed that 79 and 511 swabs were S. equi positive and negative, respectively, and the results were identical to those of the culture examination. These results indicate that the seM-LAMP is potentially useful for the reliable routine diagnosis of Streptococcus equi subsp. equi infections.

  5. Assessing Actual Visit Behavior through Antecedents of Tourists Satisfaction among International Tourists in Jordan: A Structural Equation Modeling (SEM Approach

    Directory of Open Access Journals (Sweden)

    Ayed Moh’d Al Muala

    2011-06-01

    Full Text Available Jordan tourism industry is facing fluctuating tourist visit provoked by dissatisfaction, high visit risk, low hotel service, or negative Jordan image. This study aims to examine the relationships between the antecedents of tourist satisfaction and actual visit behavior in tourism of Jordan, and the mediating effect of tourist satisfaction (SAT in the relationship between Jordan image (JOM, service climate (SER and actual visit behavior (ACT. A total of 850 international tourists completed a survey that were conducted at southern sites in Jordan. Using structural equation modeling (SEM technique, confirmatory Factor Analysis (CFA was performed to examine the reliability and validity of the measurement, and the structural equation modeling techniques (Amos 6.0 were used to evaluate the casual model. Results of the study demonstrate the strong predictive power and explain of international tourists’ behavior in Jordan. The findings highlighted that the relationship between Jordan image and service climate are significant and positive on actual visit behavior.

  6. COMMIT at SemEval-2017 Task 5: Ontology-based Method for Sentiment Analysis of Financial Headlines

    NARCIS (Netherlands)

    Schouten, Kim; Frasincar, Flavius; de Jong, F.M.G.

    2017-01-01

    This paper describes our submission to Task 5 of SemEval 2017, Fine-Grained Sentiment Analysis on Financial Microblogs and News, where we limit ourselves to performing sentiment analysis on news headlines only (track 2). The approach presented in this paper uses a Support Vector Machine to do the

  7. Bottom-up nanoarchitecture of semiconductor nano-building blocks by controllable in situ SEM-FIB thermal soldering method

    KAUST Repository

    Zhang, Xuan

    2017-08-10

    Here we demonstrate that the building blocks of semiconductor WO3 nanowires can be controllably soldered together by a novel nano-soldering technique of in situ SEM-FIB thermal soldering, in which the soldering temperature can precisely remain in an optimal range to avoid a strong thermal diffusion.

  8. Bottom-up nanoarchitecture of semiconductor nano-building blocks by controllable in situ SEM-FIB thermal soldering method

    KAUST Repository

    Zhang, Xuan; Zheng, Xiujun; Zhang, Hong; Zhang, Junli; Fu, Jiecai; Zhang, Qiang; Peng, Chaoyi; Bai, Feiming; Zhang, Xixiang; Peng, Yong

    2017-01-01

    Here we demonstrate that the building blocks of semiconductor WO3 nanowires can be controllably soldered together by a novel nano-soldering technique of in situ SEM-FIB thermal soldering, in which the soldering temperature can precisely remain in an optimal range to avoid a strong thermal diffusion.

  9. A measuring system for mechanical characterization of thin films based on a compact in situ micro-tensile tester and SEM moiré method

    International Nuclear Information System (INIS)

    Li, Yanjie; Tang, Minjin; Xie, Huimin; Zhu, Ronghua; Luo, Qiang; Gu, Changzhi

    2013-01-01

    A measuring system for mechanical characterization of thin films based on a compact in situ micro-tensile tester and scanning electron microscope (SEM) moiré method is proposed. The load is exerted by the tensile tester and the full field strain is measured by SEM moiré method. The configuration of the tensile tester and the principle of SEM moiré method are introduced. In the tensile tester, a lever structure is designed to amplify the displacement imposed by lead–zirconate–titanate (PZT) actuator. The SEM moiré method is applied to measure the strain of the thin film, including both the average strain in the gage section and the local strain distribution at a specific region. As an application, the measuring system is applied to characterize the mechanical property of the free-standing aluminum thin film. The experimental results demonstrate the feasibility of the system and its good application potential for mechanical behavior analysis of film-like materials. (paper)

  10. SEM method for direct visual tracking of nanoscale morphological changes of platinum based electrocatalysts on fixed locations upon electrochemical or thermal treatments

    Energy Technology Data Exchange (ETDEWEB)

    Zorko, Milena [National Institute of Chemistry, Hajdrihova 19, Ljubljana (Slovenia); Centre of Excellence for Low-Carbon Technologies, Hajdrihova 19, Ljubljana (Slovenia); Jozinović, Barbara [Centre of Excellence for Low-Carbon Technologies, Hajdrihova 19, Ljubljana (Slovenia); Bele, Marjan [National Institute of Chemistry, Hajdrihova 19, Ljubljana (Slovenia); Centre of Excellence for Low-Carbon Technologies, Hajdrihova 19, Ljubljana (Slovenia); Hodnik, Nejc, E-mail: nejc.hodnik@ki.si [National Institute of Chemistry, Hajdrihova 19, Ljubljana (Slovenia); Gaberšček, Miran [National Institute of Chemistry, Hajdrihova 19, Ljubljana (Slovenia); Centre of Excellence for Low-Carbon Technologies, Hajdrihova 19, Ljubljana (Slovenia)

    2014-05-01

    A general method for tracking morphological surface changes on a nanometer scale with scanning electron microscopy (SEM) is introduced. We exemplify the usefulness of the method by showing consecutive SEM images of an identical location before and after the electrochemical and thermal treatments of platinum-based nanoparticles deposited on a high surface area carbon. Observations reveal an insight into platinum based catalyst degradation occurring during potential cycling treatment. The presence of chloride clearly increases the rate of degradation. At these conditions the dominant degradation mechanism seems to be the platinum dissolution with some subsequent redeposition on the top of the catalyst film. By contrast, at the temperature of 60 °C, under potentiostatic conditions some carbon corrosion and particle aggregation was observed. Temperature treatment simulating the annealing step of the synthesis reveals sintering of small platinum based composite aggregates into uniform spherical particles. The method provides a direct proof of induced surface phenomena occurring on a chosen location without the usual statistical uncertainty in usual, random SEM observations across relatively large surface areas. - Highlights: • A new SEM method for observations of identical locations. • Nanoscale morphological consecutive changes on identical locations. • Electrochemical and thermal treatments on platinum based nanoparticles. • Potential cycling induces platinum dissolution with redeposition on top of the film. • At 1.4 V vs. RHE and 60 °C carbon corrosion and particle aggregation is observed.

  11. The Effect of Nonnormality on CB-SEM and PLS-SEM Path Estimates

    OpenAIRE

    Z. Jannoo; B. W. Yap; N. Auchoybur; M. A. Lazim

    2014-01-01

    The two common approaches to Structural Equation Modeling (SEM) are the Covariance-Based SEM (CB-SEM) and Partial Least Squares SEM (PLS-SEM). There is much debate on the performance of CB-SEM and PLS-SEM for small sample size and when distributions are nonnormal. This study evaluates the performance of CB-SEM and PLS-SEM under normality and nonnormality conditions via a simulation. Monte Carlo Simulation in R programming language was employed to generate data based on the theoretical model w...

  12. Palyno-morphological characteristics of gymnosperm flora of pakistan and its taxonomic implications with LM and SEM methods.

    Science.gov (United States)

    Khan, Raees; Ul Abidin, Sheikh Zain; Ahmad, Mushtaq; Zafar, Muhammad; Liu, Jie; Amina, Hafiza

    2018-01-01

    The present study is intended to assess gymnosperms pollen flora of Pakistan using Light Microscope (LM) and Scanning Electron Microscopy (SEM) for its taxonomic significance in identification of gymnosperms. Pollens of 35 gymnosperm species (12 genera and five families) were collected from its various distributional sites of gymnosperms in Pakistan. LM and SEM were used to investigate different palyno-morphological characteristics. Five pollen types (i.e., Inaperturate, Monolete, Monoporate, Vesiculate-bisaccate and Polyplicate) were observed. Six In equatorial view seven types of pollens were observed, in which ten species were sub-angular, nine species were Traingular, six species were Perprolate, three species were Rhomboidal, three species were semi-angular, two species were rectangular and two species were prolate. While five types of pollen were observed in polar view, in which ten species were Spheroidal, nine species were Angular, eight were Interlobate, six species were Circular, two species were Elliptic. Eighteen species has rugulate and 17 species has faveolate ornamentation. Eighteen species has verrucate and 17 have gemmate type sculpturing. The data was analysed through cluster analysis. The study showed that these palyno-morphological features have significance value in classification and identification of gymnosperms. Based on these different palyno-morphological features, a taxonomic key was proposed for the accurate and fast identifications of gymnosperms from Pakistan. © 2017 Wiley Periodicals, Inc.

  13. EXPLORING MEDIATING ROLE OF INSTITUTIONAL IMAGE THROUGH A COMPLETE STRUCTURAL EQUATION MODELING (SEM: A PERSPECTVE OF HIGHER EDUCATION

    Directory of Open Access Journals (Sweden)

    Abu Osman

    2018-06-01

    Full Text Available The prime objective of this study is to investigate the mediating role of institutional image between student satisfaction, program quality, and service quality in the context of higher education. To attain this aim, the Nordic model was used as theoretical foundation of the study. The Structural Equation Modeling (SEM was used to analyze the influence of mediating variable and hypotheses testing. The population of this study was fourth-year business students of nine 'grade one' private universities in Bangladesh. Data (n=310 were gathered from students pursuing studies at different private universities in Bangladesh. The findings of this study revealed that image occupied full mediation role between student satisfaction and service quality. Furthermore, it also disclosed that the direct path of student satisfaction and service quality was not statistically significant. These exceptional findings indicate that academic experts should promote the institutional image, student satisfaction and program quality rigorously in order to enhance service quality of education. The outcomes of this study would provide substantial benefits to both practitioners and academics, especially in the context of private higher education. There is a deficiency of indirect link between student satisfaction, program quality and service quality. This study has integrated institutional image as a mediating variable to fulfill the deficiency between student satisfaction, program quality, and service quality.

  14. Chapter 24: Strategic Energy Management (SEM) Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, James [The Cadmus Group, Portland, OR (United States)

    2017-05-18

    Strategic energy management (SEM) focuses on achieving energy-efficiency improvements through systematic and planned changes in facility operations, maintenance, and behaviors (OM&B) and capital equipment upgrades in large energy-using facilities, including industrial buildings, commercial buildings, and multi-facility organizations such as campuses or communities. Facilities can institute a spectrum of SEM actions, ranging from a simple process for regularly identifying energy-savings actions, to establishing a formal, third-party recognized or certified SEM framework for continuous improvement of energy performance. In general, SEM programs that would be considered part of a utility program will contain a set of energy-reducing goals, principles, and practices emphasizing continuous improvements in energy performance or savings through energy management and an energy management system (EnMS).

  15. Application of the Matrix Pencil Method for Estimating the SEM (Singularity Expansion Method) Poles of Source Free Transient Responses From Multiple Look Directions

    National Research Council Canada - National Science Library

    Sarkar, Tapan

    2000-01-01

    .... The SEM poles are independent of the angle at which the transient response is recorded. The only difference between the various waveforms are that the residues at the various poles are of different magnitudes...

  16. SEM method for direct visual tracking of nanoscale morphological changes of platinum based electrocatalysts on fixed locations upon electrochemical or thermal treatments.

    Science.gov (United States)

    Zorko, Milena; Jozinović, Barbara; Bele, Marjan; Hodnik, Nejc; Gaberšček, Miran

    2014-05-01

    A general method for tracking morphological surface changes on a nanometer scale with scanning electron microscopy (SEM) is introduced. We exemplify the usefulness of the method by showing consecutive SEM images of an identical location before and after the electrochemical and thermal treatments of platinum-based nanoparticles deposited on a high surface area carbon. Observations reveal an insight into platinum based catalyst degradation occurring during potential cycling treatment. The presence of chloride clearly increases the rate of degradation. At these conditions the dominant degradation mechanism seems to be the platinum dissolution with some subsequent redeposition on the top of the catalyst film. By contrast, at the temperature of 60°C, under potentiostatic conditions some carbon corrosion and particle aggregation was observed. Temperature treatment simulating the annealing step of the synthesis reveals sintering of small platinum based composite aggregates into uniform spherical particles. The method provides a direct proof of induced surface phenomena occurring on a chosen location without the usual statistical uncertainty in usual, random SEM observations across relatively large surface areas. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A simple method for detection of gunshot residue particles from hands, hair, face, and clothing using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX).

    Science.gov (United States)

    Kage, S; Kudo, K; Kaizoji, A; Ryumoto, J; Ikeda, H; Ikeda, N

    2001-07-01

    We devised a simple and rapid method for detection of gunshot residue (GSR) particles, using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX) analysis. Experiments were done on samples containing GSR particles obtained from hands, hair, face, and clothing, using double-sided adhesive coated aluminum stubs (tape-lift method). SEM/WDX analyses for GSR were carried out in three steps: the first step was map analysis for barium (Ba) to search for GSR particles from lead styphnate primed ammunition, or tin (Sn) to search for GSR particles from mercury fulminate primed ammunition. The second step was determination of the location of GSR particles by X-ray imaging of Ba or Sn at a magnification of x 1000-2000 in the SEM, using data of map analysis, and the third step was identification of GSR particles, using WDX spectrometers. Analysis of samples from each primer of a stub took about 3 h. Practical applications were shown for utility of this method.

  18. Assessing the impacts of human activities and climate variations on grassland productivity by partial least squares structural equation modeling (PLS-SEM)

    Institute of Scientific and Technical Information of China (English)

    SHA Zongyao; XIE Yichun; TAN Xicheng; BAI Yongfei; LI Jonathan; LIU Xuefeng

    2017-01-01

    The cause-effect associations between geographical phenomena are an important focus in ecological research.Recent studies in structural equation modeling (SEM) demonstrated the potential for analyzing such associations.We applied the variance-based partial least squares SEM (PLS-SEM) and geographically-weighted regression (GWR) modeling to assess the human-climate impact on grassland productivity represented by above-ground biomass (AGB).The human and climate factors and their interaction were taken to explain the AGB variance by a PLS-SEM developed for the grassland ecosystem in Inner Mongolia,China.Results indicated that 65.5% of the AGB variance could be explained by the human and climate factors and their interaction.The case study showed that the human and climate factors imposed a significant and negative impact on the AGB and that their interaction alleviated to some extent the threat from the intensified human-climate pressure.The alleviation may be attributable to vegetation adaptation to high human-climate stresses,to human adaptation to climate conditions or/and to recent vegetation restoration programs in the highly degraded areas.Furthermore,the AGB response to the human and climate factors modeled by GWR exhibited significant spatial variations.This study demonstrated that the combination of PLS-SEM and GWR model is feasible to investigate the cause-effect relation in socio-ecological systems.

  19. Nutrition, Balance and Fear of Falling as Predictors of Risk for Falls among Filipino Elderly in Nursing Homes: A Structural Equation Model (SEM)

    Science.gov (United States)

    de Guzman, Allan B.; Ines, Joanna Louise C.; Inofinada, Nina Josefa A.; Ituralde, Nielson Louie J.; Janolo, John Robert E.; Jerezo, Jnyv L.; Jhun, Hyae Suk J.

    2013-01-01

    While a number of empirical studies have been conducted regarding risk for falls among the elderly, there is still a paucity of similar studies in a developing country like the Philippines. This study purports to test through Structural Equation Modeling (SEM) a model that shows the interaction between and among nutrition, balance, fear of…

  20. Ao leitor sem medo

    Directory of Open Access Journals (Sweden)

    José Eisenberg

    2000-05-01

    Full Text Available O texto resenha Ao leitor sem medo, de Renato Janine Ribeiro (Belo Horizonte, UFMG, 1999.This text is a review of Ao leitor sem medo by Renato Janine Ribeiro (Belo Horizonte, UFMG, 1999

  1. Sexual Arousal and Sexually Explicit Media (SEM)

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Stulhofer, Aleksandar; Lange, Theis

    2018-01-01

    -mainstream and mainstream SEM groups, and (iii) to explore the validity and predictive accuracy of the Non-Mainstream Pornography Arousal Scale (NPAS). METHODS: Online cross-sectional survey of 2,035 regular SEM users in Croatia. MAIN OUTCOMES MEASURES: Patterns of sexual arousal to 27 different SEM themes, sexual...

  2. Subepidermal moisture (SEM) and bioimpedance: a literature review of a novel method for early detection of pressure-induced tissue damage (pressure ulcers).

    Science.gov (United States)

    Moore, Zena; Patton, Declan; Rhodes, Shannon L; O'Connor, Tom

    2017-04-01

    Current detection of pressure ulcers relies on visual and tactile changes at the skin surface, but physiological changes below the skin precede surface changes and have a significant impact on tissue health. Inflammatory and apoptotic/necrotic changes in the epidermal and dermal layers of the skin, such as changes in interstitial fluid (also known as subepidermal moisture (SEM)), may precede surface changes by 3-10 days. Those same epidermal and subepidermal changes result in changes in the electrical properties (bioimpedance) of the tissue, thereby presenting an objective, non-invasive method for assessing tissue damage. Clinical studies of bioimpedance for the detection of pressure ulcers have demonstrated that changes in bioimpedance correlate with increasing severity of pressure ulcer stages. Studies have also demonstrated that at anatomical locations with pressure ulcers, bioimpedance varies with distance from the centre of the pressure ulcers. The SEM Scanner, a handheld medical device, offers an objective and reliable method for the assessment of local bioimpedance, and therefore, assessment of tissue damage before signs become visible to the unaided eye. This literature review summarises pressure ulcer pathophysiology, principles of bioimpedance and clinical research using bioimpedance technology to assess pressure ulcers. © 2016 The Authors. International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  3. Model Correction Factor Method

    DEFF Research Database (Denmark)

    Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes

    1997-01-01

    The model correction factor method is proposed as an alternative to traditional polynomial based response surface techniques in structural reliability considering a computationally time consuming limit state procedure as a 'black box'. The class of polynomial functions is replaced by a limit...... of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods...

  4. Study of the magnetic microstructure of high-coercivity sintered SmCo5 permanent magnets with the conventional Bitter pattern technique and the colloid-SEM method

    International Nuclear Information System (INIS)

    Szmaja, Witold

    2007-01-01

    The magnetic microstructure of high-coercivity sintered SmCo 5 permanent magnets was studied with the conventional Bitter pattern technique, and also for the first time with the colloid-scanning electron microscopy (colloid-SEM) method. Both techniques were supported by digital image acquisition, enhancement and analysis. Thanks to this, it was possible to obtain high-contrast and clear images of the magnetic microstructure and to analyze them in detail, and consequently also to achieve improvements over earlier results. In the thermally demagnetized state the grains were composed of magnetic domains. On the surface perpendicular to the alignment axis, the main domains forming a maze pattern and surface reverse spikes were observed. Investigations on the surface parallel to the alignment axis, especially by the colloid-SEM technique, provided a detailed insight into the orientation of grains. The alignment of grains was good, but certainly not perfect; there were also strongly misaligned grains, although generally very rare. In most cases the domain structures within grains were independent of their neighbors, but in some cases (not so rare) the domain walls were observed to continue through the grain boundaries, indicating significant magnetostatic interaction between neighboring grains. Studies of the behavior of the magnetic microstructure under the influence of an external magnetic field, performed for the first time on the surface parallel to the alignment axis (with the conventional Bitter pattern method), showed that the domain walls move easily within the grains and that the magnetization reversal mechanism is mainly related to the nucleation and growth of reverse domains, i.e. that sintered SmCo 5 magnets are nucleation-dominated systems. Groupwise magnetization reversal of adjacent magnetically coupled grains was observed, an unfavorable effect for high-coercivity magnets. Images obtained by the colloid-SEM technique and the conventional Bitter pattern

  5. Cheap non-toxic non-corrosive method of glass cleaning evaluated by contact angle, AFM, and SEM-EDX measurements.

    Science.gov (United States)

    Dey, Tania; Naughton, Daragh

    2017-05-01

    Glass surface cleaning is the very first step in advanced coating deposition and it also finds use in conserving museum objects. However, most of the wet chemical methods of glass cleaning use toxic and corrosive chemicals like concentrated sulfuric acid (H 2 SO 4 ), piranha (a mixture of concentrated sulfuric acid and 30% hydrogen peroxide), and hydrogen fluoride (HF). On the other hand, most of the dry cleaning techniques like UV-ozone, plasma, and laser treatment require costly instruments. In this report, five eco-friendly wet chemical methods of glass cleaning were evaluated in terms of contact angle (measured by optical tensiometer), nano-scale surface roughness (measured by atomic force microscopy or AFM), and elemental composition (measured by energy dispersive x-ray spectroscopy or SEM-EDX). These glass cleaning methods are devoid of harsh chemicals and costly equipment, hence can be applied in situ in close proximity with plantation such as greenhouse or upon subtle objects such as museum artifacts. Out of these five methods, three methods are based on the chemical principle of chelation. It was found that the citric acid cleaning method gave the greatest change in contact angle within the hydrophilic regime (14.25° for new glass) indicating effective cleansing and the least surface roughness (0.178 nm for new glass) indicating no corrosive effect. One of the glass sample showed unique features which were traced backed to the history of the glass usage.

  6. Advanced SEM imaging

    International Nuclear Information System (INIS)

    Joy, D. C.; Newbury, D. E.

    1998-01-01

    The scanning electron microscope (SEM) represents the most promising tool for metrology, defect review, and for the analysis of ULSI structures, but both fundamental problems such as electron-solid interactions, and practical considerations such as electron-optical constraints, are now setting a limit to performance. This paper examines the directions in which an advanced SEM might be developed to overcome these constraints. The SEM also offers considerable promise as a tool for the high spatial resolution X-ray microanalysis, especially for those situations where a thin cross-section is not practical and first surface analysis is required. The ways in which this capability can be incorporated in an advanced SEM are examined

  7. Advanced SEM imaging

    International Nuclear Information System (INIS)

    Joy, D.C.; Newbury, D.E.; Newbury, D.E.

    1998-01-01

    The scanning electron microscope (SEM) represents the most promising tool for metrology, defect review, and for the analysis of ULSI structures, but both fundamental problems such as electron-solid interactions, and practical considerations such as electron-optical constraints, are now setting a limit to performance. This paper examines the directions in which an advanced SEM might be developed to overcome these constraints. The SEM also offers considerable promise as a tool for the high spatial resolution X-ray microanalysis, especially for those situations where a thin cross-section is not practical and first surface analysis is required. The ways in which this capability can be incorporated in an advanced SEM are examined. copyright 1998 American Institute of Physics

  8. FAKTOR ADOPSI INTERNET MARKETING UNTUK USAHA MIKRO DAN USAHA KECIL MENENGAH (UMKM DI KABUPATEN KUDUS DENGAN SEM (STRUCTURAL EQUATION MODEL DAN FRAMEWORK COBIT 4.1

    Directory of Open Access Journals (Sweden)

    Endang Supriyati

    2013-06-01

    Full Text Available ABSTRAK Pemasaran melalui internet merupakan strategi baru dalam era teknologi informasi saat ini. Teknologi informasi diarahkan untuk mendukung proses bisnis utama dan pendukung yang ada di Usaha Mikro Dan Usaha Kecil Menengah (UMKM. Penelitian ini dilakukan pada UMKM di Kab Kudus yang bergerak di bidang konveksi dan kerajinan bordir. Analisa terhadap Tata Kelola TI diperoleh Domain COBIT yang sesuai yaitu PO5 (Mengukur Investasi TI. Indikator yang dianalisa adalah indikator penggunaan internet marketing. Dari identifikasi ini, kuisioner disebar ke UMKM. Pendekatan Struktural Equation Modeling (SEM digunakan untuk menganalisa secara empiris tentang faktor-faktor yang terkait dengan penggunaan internet marketing dalam memasarkan produk UMKM. Dari hasil penelitian ini menunjukkan bahwa korelasi Internet Marketing dengan PO5 cukup kuat (-0,358 akan tetapi arahnya negatif sehingga semakin kecil pengaturan investasi TI semakin kecil juga penggunaan Internet Marketing. Kata Kunci : UMKM, Internet marketing, COBIT, PO5, SEM

  9. TRAC methods and models

    International Nuclear Information System (INIS)

    Mahaffy, J.H.; Liles, D.R.; Bott, T.F.

    1981-01-01

    The numerical methods and physical models used in the Transient Reactor Analysis Code (TRAC) versions PD2 and PF1 are discussed. Particular emphasis is placed on TRAC-PF1, the version specifically designed to analyze small-break loss-of-coolant accidents

  10. Spectral-element Method for 3D Marine Controlled-source EM Modeling

    Science.gov (United States)

    Liu, L.; Yin, C.; Zhang, B., Sr.; Liu, Y.; Qiu, C.; Huang, X.; Zhu, J.

    2017-12-01

    As one of the predrill reservoir appraisal methods, marine controlled-source EM (MCSEM) has been widely used in mapping oil reservoirs to reduce risk of deep water exploration. With the technical development of MCSEM, the need for improved forward modeling tools has become evident. We introduce in this paper spectral element method (SEM) for 3D MCSEM modeling. It combines the flexibility of finite-element and high accuracy of spectral method. We use Galerkin weighted residual method to discretize the vector Helmholtz equation, where the curl-conforming Gauss-Lobatto-Chebyshev (GLC) polynomials are chosen as vector basis functions. As a kind of high-order complete orthogonal polynomials, the GLC have the characteristic of exponential convergence. This helps derive the matrix elements analytically and improves the modeling accuracy. Numerical 1D models using SEM with different orders show that SEM method delivers accurate results. With increasing SEM orders, the modeling accuracy improves largely. Further we compare our SEM with finite-difference (FD) method for a 3D reservoir model (Figure 1). The results show that SEM method is more effective than FD method. Only when the mesh is fine enough, can FD achieve the same accuracy of SEM. Therefore, to obtain the same precision, SEM greatly reduces the degrees of freedom and cost. Numerical experiments with different models (not shown here) demonstrate that SEM is an efficient and effective tool for MSCEM modeling that has significant advantages over traditional numerical methods.This research is supported by Key Program of National Natural Science Foundation of China (41530320), China Natural Science Foundation for Young Scientists (41404093), and Key National Research Project of China (2016YFC0303100, 2017YFC0601900).

  11. Spin-polarized SEM

    International Nuclear Information System (INIS)

    Konoto, Makoto

    2007-01-01

    Development of highly effective evaluation technology of magnetic structures on a nanometric scale is a key to understanding spintronics and related phenomena. A high-resolution spin-polarized scanning electron microscope (spin SEM) developed recently is quite suitable for probing such nanostructures because of the capability of analyzing local magnetization vectors in three dimensions. Utilizing the spin SEM, a layered antiferromagnetic structure with the 1nm-alternation of bilayer-sheet magnetization has been successfully resolved. The real-space imaging with full analysis of the temperature-dependent magnetization vectors will be demonstrated. (author)

  12. Um modelo semântico de publicações eletrônicas | A semantic model for electronic publishing

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Marcondes

    2011-03-01

    Full Text Available Resumo Publicações eletrônicas, apesar dos avanços das Tecnologias da Informação, são ainda calcados no modelo impresso. O formato textual impede que programas possam ser usados para o processamento “semântico” desses conteúdos. È porposto um modelo “semântico” de publicações cientificas eletrônicas, no qual as conclusões contidas no texto do artigo fornecidas por autores e representadas em formato “inteligível” por programas, permitindo recuperação semântica, identificação de indícios de novas descobertas científicas e de incoerências sobre este conhecimento. O modelo se baseia nos conceitos de estrutura profunda, ou semântica, da linguagem (CHOMSKY, 1975, de microestrutura, macroestrutura e superestrutura, (KINTSH, VAN DIJK, 1972, na estrutura retórica de artigos científicos (HUTCHINS, 1977, (GROSS, 1990 e nos elementos de metodologia cientifica, como problema, questão, objetivo, hipótese, experimento e conclusão. Resulta da análise de 89 artigos biomédicos. Foi desenvolvido um protótipo de sistema que implementa parcialmente o modelo. Questionários foram usados com autores para embasar o desenvolvimento do protótipo. O protótipo foi testando com pesquisadores-autores. Foram identificados quatro padrões de raciocínio e encadeamento dos elementos semânticos em artigos científicos. O modelo de conteúdo foi implementado como uma ontologia computacional. Foi desenvolvido e avaliado um protótipo de uma interface web de submissão artigos pelos autores a um sistema eletrônico de publicação de periódicos que implementa o modelo. Palavras-chave publicações eletrônicas; metodológica científica; comunicação científica; representação do conhecimento; ontologias; processamento semântico de conteúdos; e-Ciência Abstract Electronic publishing, although Information Technologies advancements, are still based in the print text model. The textual format prevents programs to semantic process

  13. SEM microcharacterization of semiconductors

    CERN Document Server

    Holt, D B

    1989-01-01

    Applications of SEM techniques of microcharacterization have proliferated to cover every type of material and virtually every branch of science and technology. This book emphasizes the fundamental physical principles. The first section deals with the foundation of microcharacterization in electron beam instruments and the second deals with the interpretation of the information obtained in the main operating modes of a scanning electron microscope.

  14. UV irradiation of track membranes as a method for obtaining the necessary value of brittleness for good fractures of samples for sem observations

    International Nuclear Information System (INIS)

    Sartowska, B.; Nowicki, A.; Orelovitch, O.; )

    2006-01-01

    Synthesis of nano- and microstructures of materials inside the pores of specific template-track membranes can be used to obtain nano- and microwires or nano- and microtubes. It is important for these applications to know the inner geometry of the pores like sizes, shape and surface morphology. Scanning electron microscopy technique (SEM) was used predominantly for this kind of membrane characterisation. The use of other methods of sample preparation as electron, gamma rays or UV irradiation allows to make them more brittle. In present paper authors describe preliminary results of the tensile measurements of membranes after UV irradiation. Poly(ethylene terephthalate) (PET) membrane 10 μm thick with pore diameter 1.0 μm were prepared t the Joint Institute for Nuclear Research (Dubna, Russia) using the standard procedure. The samples were irradiated with UV light with energy flux 2.8 W/cm 2 during different periods of time. The tensile measurements of the initial and irradiated materials were carried in the Institute of Nuclear Chemistry and Technology (Warsaw, Poland). In conclusion, authors claim that it is possible to find the dose of UV irradiation that ensures the fracture without elastic deformation. In the case when the time of UV irradiation increases up to 90 h, the PET membrane breaks without distortion of its channel structure

  15. Combined SEM/AVS and attenuation of concentration models for the assessment of bioavailability and mobility of metals in sediments of Sepetiba Bay (SE Brazil).

    Science.gov (United States)

    Ribeiro, Andreza Portella; Figueiredo, Ana Maria Graciano; dos Santos, José Osman; Dantas, Elizabeth; Cotrim, Marycel Elena Barboza; Figueira, Rubens Cesar Lopes; Silva Filho, Emmanoel V; Wasserman, Julio Cesar

    2013-03-15

    This study proposes a new methodology to study contamination, bioavailability and mobility of metals (Cd, Cu, Ni, Pb, and Zn) using chemical and geostatistics approaches in marine sediments of Sepetiba Bay (SE Brazil). The chemical model of SEM (simultaneously extracted metals)/AVS (acid volatile sulfides) ratio uses a technique of cold acid extraction of metals to evaluate their bioavailability, and the geostatistical model of attenuation of concentrations estimates the mobility of metals. By coupling the two it was observed that Sepetiba Port, the urban area of Sepetiba and the riverine discharges may constitute potential sources of metals to Sepetiba Bay. The metals are concentrated in the NE area of the bay, where they tend to have their lowest mobility, as shown by the attenuation model, and are not bioavailable, as they tend to associate with sulfide and organic matter originated in the mangrove forests of nearby Guaratiba area. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Space Experiment Module (SEM)

    Science.gov (United States)

    Brodell, Charles L.

    1999-01-01

    The Space Experiment Module (SEM) Program is an education initiative sponsored by the National Aeronautics and Space Administration (NASA) Shuttle Small Payloads Project. The program provides nationwide educational access to space for Kindergarten through University level students. The SEM program focuses on the science of zero-gravity and microgravity. Within the program, NASA provides small containers or "modules" for students to fly experiments on the Space Shuttle. The experiments are created, designed, built, and implemented by students with teacher and/or mentor guidance. Student experiment modules are flown in a "carrier" which resides in the cargo bay of the Space Shuttle. The carrier supplies power to, and the means to control and collect data from each experiment.

  17. Modes of Occurrence of Fluorine by Extraction and SEM Method in a Coal-Fired Power Plant from Inner Mongolia, China

    Directory of Open Access Journals (Sweden)

    Guangmeng Wang

    2015-12-01

    Full Text Available In this study, an extraction method and environmental scanning electron microscopy (SEM are employed to reveal the changes in the occurrence mode of fluorine in a coal-fired power plant in Inner Mongolia, China. The different occurrence states of fluorine during coal combustion and emission show that fluorine in coal mainly assumes insoluble inorganic mineral forms. The results illustrate that the three typical occurrence modes in coal are CaF2, MgF2 and AlF3. The fluorine in fly ash can be captured by an electrostatic precipitator (EPS or a bag filter. In contrast, the gaseous fluorine content in flue gas is only in the range of several parts per million; thus, it cannot be used in this study. The occurrence mode of fluorine in bottom ash and slag is inorganic villiaumite (e.g., soluble NaF, KF and insoluble CaF2 which is difficult to break down even at high temperatures. The occurrence mode of fluorine with the highest content in fly ash is physically adsorbed fluorine along the direction of the flue gas flow. The insoluble inorganic mineral fluoride content in fly ash is also high, but the gradually increasing fluorine content in fly ash is mainly caused by physical adsorption. Fluorine in the coal-fired power plant discharges mostly as solid products; however, very little fluorine emitted into the environment as gas products (HF, SiF4 cannot be captured. The parameters used in this study may provide useful references in developing a monitoring and control system for fluorine in coal-fired power plants.

  18. Framework for SEM contour analysis

    Science.gov (United States)

    Schneider, L.; Farys, V.; Serret, E.; Fenouillet-Beranger, C.

    2017-03-01

    SEM images provide valuable information about patterning capability. Geometrical properties such as Critical Dimension (CD) can be extracted from them and are used to calibrate OPC models, thus making OPC more robust and reliable. However, there is currently a shortage of appropriate metrology tools to inspect complex two-dimensional patterns in the same way as one would work with simple one-dimensional patterns. In this article we present a full framework for the analysis of SEM images. It has been proven to be fast, reliable and robust for every type of structure, and particularly for two-dimensional structures. To achieve this result, several innovative solutions have been developed and will be presented in the following pages. Firstly, we will present a new noise filter which is used to reduce noise on SEM images, followed by an efficient topography identifier, and finally we will describe the use of a topological skeleton as a measurement tool that can extend CD measurements on all kinds of patterns.

  19. O Cinema sem Imagens

    Directory of Open Access Journals (Sweden)

    Paulo Andrade

    2001-12-01

    Full Text Available A obra cinematográfica de Marguerite Duras, praticamente desconhecida pelo grande público, estabeleça intricadas relações com sua obra literária, ao promover a indiscernibilidade entre os dois campo, sem, contudo, instituir qualquer tipo de subordinação de um ao outro. O processo de criação do filme Lê camion, de 1977, aponta para outras possibilidades de se pensar o cinema e a literatura.

  20. Explorative methods in linear models

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar

    2004-01-01

    The author has developed the H-method of mathematical modeling that builds up the model by parts, where each part is optimized with respect to prediction. Besides providing with better predictions than traditional methods, these methods provide with graphic procedures for analyzing different feat...... features in data. These graphic methods extend the well-known methods and results of Principal Component Analysis to any linear model. Here the graphic procedures are applied to linear regression and Ridge Regression....

  1. Piecewise Structural Equation Model (SEM) Disentangles the Environmental Conditions Favoring Diatom Diazotroph Associations (DDAs) in the Western Tropical North Atlantic (WTNA).

    Science.gov (United States)

    Stenegren, Marcus; Berg, Carlo; Padilla, Cory C; David, Stefan-Sebastian; Montoya, Joseph P; Yager, Patricia L; Foster, Rachel A

    2017-01-01

    Diatom diazotroph associations (DDAs) are important components in the world's oceans, especially in the western tropical north Atlantic (WTNA), where blooms have a significant impact on carbon and nitrogen cycling. However, drivers of their abundances and distribution patterns remain unknown. Here, we examined abundance and distribution patterns for two DDA populations in relation to the Amazon River (AR) plume in the WTNA. Quantitative PCR assays, targeting two DDAs (het-1 and het-2) by their symbiont's nifH gene, served as input in a piecewise structural equation model (SEM). Collections were made during high (spring 2010) and low (fall 2011) flow discharges of the AR. The distributions of dissolved nutrients, chlorophyll- a , and DDAs showed coherent patterns indicative of areas influenced by the AR. A symbiotic Hemiaulus hauckii-Richelia (het-2) bloom (>10 6 cells L -1 ) occurred during higher discharge of the AR and was coincident with mesohaline to oceanic (30-35) sea surface salinities (SSS), and regions devoid of dissolved inorganic nitrogen (DIN), low concentrations of both DIP (>0.1 μmol L -1 ) and Si (>1.0 μmol L -1 ). The Richelia (het-1) associated with Rhizosolenia was only present in 2010 and at lower densities (10-1.76 × 10 5 nifH copies L -1 ) than het-2 and limited to regions of oceanic SSS (>36). The het-2 symbiont detected in 2011 was associated with H. membranaceus (>10 3 nifH copies L -1 ) and were restricted to regions with mesohaline SSS (31.8-34.3), immeasurable DIN, moderate DIP (0.1-0.60 μmol L -1 ) and higher Si (4.19-22.1 μmol L -1 ). The piecewise SEM identified a profound direct negative effect of turbidity on the het-2 abundance in spring 2010, while DIP and water turbidity had a more positive influence in fall 2011, corroborating our observations of DDAs at subsurface maximas. We also found a striking difference in the influence of salinity on DDA symbionts suggesting a niche differentiation and preferences in oceanic and

  2. Piecewise Structural Equation Model (SEM Disentangles the Environmental Conditions Favoring Diatom Diazotroph Associations (DDAs in the Western Tropical North Atlantic (WTNA

    Directory of Open Access Journals (Sweden)

    Marcus Stenegren

    2017-05-01

    Full Text Available Diatom diazotroph associations (DDAs are important components in the world’s oceans, especially in the western tropical north Atlantic (WTNA, where blooms have a significant impact on carbon and nitrogen cycling. However, drivers of their abundances and distribution patterns remain unknown. Here, we examined abundance and distribution patterns for two DDA populations in relation to the Amazon River (AR plume in the WTNA. Quantitative PCR assays, targeting two DDAs (het-1 and het-2 by their symbiont’s nifH gene, served as input in a piecewise structural equation model (SEM. Collections were made during high (spring 2010 and low (fall 2011 flow discharges of the AR. The distributions of dissolved nutrients, chlorophyll-a, and DDAs showed coherent patterns indicative of areas influenced by the AR. A symbiotic Hemiaulus hauckii-Richelia (het-2 bloom (>106 cells L-1 occurred during higher discharge of the AR and was coincident with mesohaline to oceanic (30–35 sea surface salinities (SSS, and regions devoid of dissolved inorganic nitrogen (DIN, low concentrations of both DIP (>0.1 μmol L-1 and Si (>1.0 μmol L-1. The Richelia (het-1 associated with Rhizosolenia was only present in 2010 and at lower densities (10-1.76 × 105nifH copies L-1 than het-2 and limited to regions of oceanic SSS (>36. The het-2 symbiont detected in 2011 was associated with H. membranaceus (>103nifH copies L-1 and were restricted to regions with mesohaline SSS (31.8–34.3, immeasurable DIN, moderate DIP (0.1–0.60 μmol L-1 and higher Si (4.19–22.1 μmol L-1. The piecewise SEM identified a profound direct negative effect of turbidity on the het-2 abundance in spring 2010, while DIP and water turbidity had a more positive influence in fall 2011, corroborating our observations of DDAs at subsurface maximas. We also found a striking difference in the influence of salinity on DDA symbionts suggesting a niche differentiation and preferences in oceanic and mesohaline

  3. Models and methods in thermoluminescence

    International Nuclear Information System (INIS)

    Furetta, C.

    2005-01-01

    This work contains a conference that was treated about the principles of the luminescence phenomena, the mathematical treatment concerning the thermoluminescent emission of light as well as the Randall-Wilkins model, the Garlick-Gibson model, the Adirovitch model, the May-Partridge model, the Braunlich-Scharman model, the mixed first and second order kinetics, the methods for evaluating the kinetics parameters such as the initial rise method, the various heating rates method, the isothermal decay method and those methods based on the analysis of the glow curve shape. (Author)

  4. Models and methods in thermoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Furetta, C. [ICN, UNAM, A.P. 70-543, Mexico D.F. (Mexico)

    2005-07-01

    This work contains a conference that was treated about the principles of the luminescence phenomena, the mathematical treatment concerning the thermoluminescent emission of light as well as the Randall-Wilkins model, the Garlick-Gibson model, the Adirovitch model, the May-Partridge model, the Braunlich-Scharman model, the mixed first and second order kinetics, the methods for evaluating the kinetics parameters such as the initial rise method, the various heating rates method, the isothermal decay method and those methods based on the analysis of the glow curve shape. (Author)

  5. Comparison of methods for the analysis of relatively simple mediation models.

    Science.gov (United States)

    Rijnhart, Judith J M; Twisk, Jos W R; Chinapaw, Mai J M; de Boer, Michiel R; Heymans, Martijn W

    2017-09-01

    Statistical mediation analysis is an often used method in trials, to unravel the pathways underlying the effect of an intervention on a particular outcome variable. Throughout the years, several methods have been proposed, such as ordinary least square (OLS) regression, structural equation modeling (SEM), and the potential outcomes framework. Most applied researchers do not know that these methods are mathematically equivalent when applied to mediation models with a continuous mediator and outcome variable. Therefore, the aim of this paper was to demonstrate the similarities between OLS regression, SEM, and the potential outcomes framework in three mediation models: 1) a crude model, 2) a confounder-adjusted model, and 3) a model with an interaction term for exposure-mediator interaction. Secondary data analysis of a randomized controlled trial that included 546 schoolchildren. In our data example, the mediator and outcome variable were both continuous. We compared the estimates of the total, direct and indirect effects, proportion mediated, and 95% confidence intervals (CIs) for the indirect effect across OLS regression, SEM, and the potential outcomes framework. OLS regression, SEM, and the potential outcomes framework yielded the same effect estimates in the crude mediation model, the confounder-adjusted mediation model, and the mediation model with an interaction term for exposure-mediator interaction. Since OLS regression, SEM, and the potential outcomes framework yield the same results in three mediation models with a continuous mediator and outcome variable, researchers can continue using the method that is most convenient to them.

  6. A time-resolved current method and TSC under vacuum conditions of SEM: Trapping and detrapping processes in thermal aged XLPE insulation cables

    Science.gov (United States)

    Boukezzi, L.; Rondot, S.; Jbara, O.; Boubakeur, A.

    2017-03-01

    Thermal aging of cross-linked polyethylene (XLPE) can cause serious concerns in the safety operation in high voltage system. To get a more detailed picture on the effect of thermal aging on the trapping and detrapping process of XLPE in the melting temperature range, Thermal Stimulated Current (TSC) have been implemented in a Scanning Electron Microscope (SEM) with a specific arrangement. The XLPE specimens are molded and aged at two temperatures (120 °C and 140 °C) situated close to the melting temperature of the material. The use of SEM allows us to measure both leakage and displacement currents induced in samples under electron irradiation. The first represents the conduction process of XLPE and the second gives information on the trapping of charges in the bulk of the material. TSC associated to the SEM leads to show spectra of XLPE discharge under thermal stimulation using both currents measured after electron irradiation. It was found that leakage current in the charging process may be related to the physical defects resulting in crystallinity variation under thermal aging. However the trapped charge can be affected by the carbonyl groups resulting from the thermo-oxidation degradation and the disorder in the material. It is evidenced from the TSC spectra of unaged XLPE that there is no detrapping charge under heat stimulation. Whereas the presence of peaks in the TSC spectra of thermally aged samples indicates that there is some amount of trapped charge released by heating. The detrapping behavior of aged XLPE is supported by the supposition of the existence of two trap levels: shallow traps and deep traps. Overall, physico-chemical reactions under thermal aging at high temperatures leads to the enhancement of shallow traps density and changes in range of traps depth. These changes induce degradation of electrical properties of XLPE.

  7. SEM analysis for irradiated materials

    International Nuclear Information System (INIS)

    Liu Xiaosong; Yao Liang

    2008-06-01

    A radiation-proof Scanning Electron Microscope (SEM) system is introduced. It has been widely used in various areas. For analyzing radioactive samples, normal SEM system needs lots of alterations. Based on KYKY-2800B SEM, the sample room, belt line, operating table and aerator were updated. New radiation-proof SEM system has used to analytic surface contaminated samples and RPV materials samples. An elementary means of SEM analysis for radioactive samples was studied, and this examination supported some available references for further irradiated fuel researches. (authors)

  8. Investigation of the agglomeration and amorphous transformation effects of neutron irradiation on the nanocrystalline silicon carbide (3C-SiC) using TEM and SEM methods

    Energy Technology Data Exchange (ETDEWEB)

    Huseynov, Elchin M., E-mail: elchin.h@yahoo.com [Department of Nanotechnology and Radiation Material Science, National Nuclear Research Center, Inshaatchilar pr. 4, AZ 1073 Baku (Azerbaijan); Institute of Radiation Problems of Azerbaijan National Academy of Sciences, B.Vahabzade 9, AZ 1143 Baku (Azerbaijan)

    2017-04-01

    Nanocrystalline 3C-SiC particles irradiated by neutron flux during 20 h in TRIGA Mark II light water pool type research reactor. Silicon carbide nanoparticles were analyzed by Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM) devices before and after neutron irradiation. The agglomeration of nanoparticles was studied comparatively before and after neutron irradiation. After neutron irradiation the amorphous layer surrounding the nanoparticles was analyzed in TEM device. Neutron irradiation defects in the 3C-SiC nanoparticles and other effects investigated by TEM device. The effect of irradiation on the crystal structure of the nanomaterial was studied by selected area electron diffraction (SAED) and electron diffraction patterns (EDP) analysis.

  9. Multivariate analysis: models and method

    International Nuclear Information System (INIS)

    Sanz Perucha, J.

    1990-01-01

    Data treatment techniques are increasingly used since computer methods result of wider access. Multivariate analysis consists of a group of statistic methods that are applied to study objects or samples characterized by multiple values. A final goal is decision making. The paper describes the models and methods of multivariate analysis

  10. The microscopic (optical and SEM) examination of dental calculus deposits (DCD). Potential interest in forensic anthropology of a bio-archaeological method.

    Science.gov (United States)

    Charlier, Philippe; Huynh-Charlier, Isabelle; Munoz, Olivia; Billard, Michel; Brun, Luc; de la Grandmaison, Geoffroy Lorin

    2010-07-01

    This article describes the potential interest in forensic anthropology of the microscopic analysis of dental calculus deposits (DCD), a calcified residue frequently found on the surface of teeth. Its sampling and analysis seem straightforward and relatively reproducible. Samples came from archaeological material (KHB-1 Ra's al-Khabbah and RH-5 Ra's al-Hamra, two Prehistoric graveyards located in the Sultanate of Oman, dated between the 5th and 4th millennium B.C.; Montenzio Vecchia, an Etruscan-Celtic necropolis from the north of Italy, dated between the 5th and 3rd century B.C.; body rests of Agnès Sorel, French royal mistress died in 1450 A.D.; skeleton of Pierre Hazard, French royal notary from the 15th century A.D.). Samples were studies by direct optical microscope (OM) or scanning electron microscopy (SEM). Many cytological, histological and elemental analyses were possible, producing precious data for the identification of these remains, the reconstitution of their alimentation and occupational habits, and propositions for manner of death. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Graph modeling systems and methods

    Science.gov (United States)

    Neergaard, Mike

    2015-10-13

    An apparatus and a method for vulnerability and reliability modeling are provided. The method generally includes constructing a graph model of a physical network using a computer, the graph model including a plurality of terminating vertices to represent nodes in the physical network, a plurality of edges to represent transmission paths in the physical network, and a non-terminating vertex to represent a non-nodal vulnerability along a transmission path in the physical network. The method additionally includes evaluating the vulnerability and reliability of the physical network using the constructed graph model, wherein the vulnerability and reliability evaluation includes a determination of whether each terminating and non-terminating vertex represents a critical point of failure. The method can be utilized to evaluate wide variety of networks, including power grid infrastructures, communication network topologies, and fluid distribution systems.

  12. ADOxx Modelling Method Conceptualization Environment

    Directory of Open Access Journals (Sweden)

    Nesat Efendioglu

    2017-04-01

    Full Text Available The importance of Modelling Methods Engineering is equally rising with the importance of domain specific languages (DSL and individual modelling approaches. In order to capture the relevant semantic primitives for a particular domain, it is necessary to involve both, (a domain experts, who identify relevant concepts as well as (b method engineers who compose a valid and applicable modelling approach. This process consists of a conceptual design of formal or semi-formal of modelling method as well as a reliable, migratable, maintainable and user friendly software development of the resulting modelling tool. Modelling Method Engineering cycle is often under-estimated as both the conceptual architecture requires formal verification and the tool implementation requires practical usability, hence we propose a guideline and corresponding tools to support actors with different background along this complex engineering process. Based on practical experience in business, more than twenty research projects within the EU frame programmes and a number of bilateral research initiatives, this paper introduces the phases, corresponding a toolbox and lessons learned with the aim to support the engineering of a modelling method. ”The proposed approach is illustrated and validated within use cases from three different EU-funded research projects in the fields of (1 Industry 4.0, (2 e-learning and (3 cloud computing. The paper discusses the approach, the evaluation results and derived outlooks.

  13. Diverse methods for integrable models

    NARCIS (Netherlands)

    Fehér, G.

    2017-01-01

    This thesis is centered around three topics, sharing integrability as a common theme. This thesis explores different methods in the field of integrable models. The first two chapters are about integrable lattice models in statistical physics. The last chapter describes an integrable quantum chain.

  14. Iterative method for Amado's model

    International Nuclear Information System (INIS)

    Tomio, L.

    1980-01-01

    A recently proposed iterative method for solving scattering integral equations is applied to the spin doublet and spin quartet neutron-deuteron scattering in the Amado model. The method is tested numerically in the calculation of scattering lengths and phase-shifts and results are found better than those obtained by using the conventional Pade technique. (Author) [pt

  15. Advanced metrology by offline SEM data processing

    Science.gov (United States)

    Lakcher, Amine; Schneider, Loïc.; Le-Gratiet, Bertrand; Ducoté, Julien; Farys, Vincent; Besacier, Maxime

    2017-06-01

    Today's technology nodes contain more and more complex designs bringing increasing challenges to chip manufacturing process steps. It is necessary to have an efficient metrology to assess process variability of these complex patterns and thus extract relevant data to generate process aware design rules and to improve OPC models. Today process variability is mostly addressed through the analysis of in-line monitoring features which are often designed to support robust measurements and as a consequence are not always very representative of critical design rules. CD-SEM is the main CD metrology technique used in chip manufacturing process but it is challenged when it comes to measure metrics like tip to tip, tip to line, areas or necking in high quantity and with robustness. CD-SEM images contain a lot of information that is not always used in metrology. Suppliers have provided tools that allow engineers to extract the SEM contours of their features and to convert them into a GDS. Contours can be seen as the signature of the shape as it contains all the dimensional data. Thus the methodology is to use the CD-SEM to take high quality images then generate SEM contours and create a data base out of them. Contours are used to feed an offline metrology tool that will process them to extract different metrics. It was shown in two previous papers that it is possible to perform complex measurements on hotspots at different process steps (lithography, etch, copper CMP) by using SEM contours with an in-house offline metrology tool. In the current paper, the methodology presented previously will be expanded to improve its robustness and combined with the use of phylogeny to classify the SEM images according to their geometrical proximities.

  16. SEM: A user's manual for materials science

    International Nuclear Information System (INIS)

    Gabriel, B.L.

    1985-01-01

    This book provides a reference of techniques used by the metallurgical microscopist. It contains an introduction to the instrumentation and methods of scanning electron microscopy with historical as well as state-of-the-art methodologies. Topics covered include: SEM instrumentation, photography, energy dispersive spectroscopy, introduction to sample preparation, polished samples, fracture surfaces, replicas and thin films

  17. Variational methods in molecular modeling

    CERN Document Server

    2017-01-01

    This book presents tutorial overviews for many applications of variational methods to molecular modeling. Topics discussed include the Gibbs-Bogoliubov-Feynman variational principle, square-gradient models, classical density functional theories, self-consistent-field theories, phase-field methods, Ginzburg-Landau and Helfrich-type phenomenological models, dynamical density functional theory, and variational Monte Carlo methods. Illustrative examples are given to facilitate understanding of the basic concepts and quantitative prediction of the properties and rich behavior of diverse many-body systems ranging from inhomogeneous fluids, electrolytes and ionic liquids in micropores, colloidal dispersions, liquid crystals, polymer blends, lipid membranes, microemulsions, magnetic materials and high-temperature superconductors. All chapters are written by leading experts in the field and illustrated with tutorial examples for their practical applications to specific subjects. With emphasis placed on physical unders...

  18. Methods for testing transport models

    International Nuclear Information System (INIS)

    Singer, C.; Cox, D.

    1993-01-01

    This report documents progress to date under a three-year contract for developing ''Methods for Testing Transport Models.'' The work described includes (1) choice of best methods for producing ''code emulators'' for analysis of very large global energy confinement databases, (2) recent applications of stratified regressions for treating individual measurement errors as well as calibration/modeling errors randomly distributed across various tokamaks, (3) Bayesian methods for utilizing prior information due to previous empirical and/or theoretical analyses, (4) extension of code emulator methodology to profile data, (5) application of nonlinear least squares estimators to simulation of profile data, (6) development of more sophisticated statistical methods for handling profile data, (7) acquisition of a much larger experimental database, and (8) extensive exploratory simulation work on a large variety of discharges using recently improved models for transport theories and boundary conditions. From all of this work, it has been possible to define a complete methodology for testing new sets of reference transport models against much larger multi-institutional databases

  19. Shell model Monte Carlo methods

    International Nuclear Information System (INIS)

    Koonin, S.E.; Dean, D.J.; Langanke, K.

    1997-01-01

    We review quantum Monte Carlo methods for dealing with large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in fluctuating one-body fields; the resultant path integral is evaluated stochastically. We first discuss the motivation, formalism, and implementation of such Shell Model Monte Carlo (SMMC) methods. There then follows a sampler of results and insights obtained from a number of applications. These include the ground state and thermal properties of pf-shell nuclei, the thermal and rotational behavior of rare-earth and γ-soft nuclei, and the calculation of double beta-decay matrix elements. Finally, prospects for further progress in such calculations are discussed. (orig.)

  20. Shell model Monte Carlo methods

    International Nuclear Information System (INIS)

    Koonin, S.E.

    1996-01-01

    We review quantum Monte Carlo methods for dealing with large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in fluctuating one-body fields; resultant path integral is evaluated stochastically. We first discuss the motivation, formalism, and implementation of such Shell Model Monte Carlo methods. There then follows a sampler of results and insights obtained from a number of applications. These include the ground state and thermal properties of pf-shell nuclei, thermal behavior of γ-soft nuclei, and calculation of double beta-decay matrix elements. Finally, prospects for further progress in such calculations are discussed. 87 refs

  1. FIB-SEM tomography in biology.

    Science.gov (United States)

    Kizilyaprak, Caroline; Bittermann, Anne Greet; Daraspe, Jean; Humbel, Bruno M

    2014-01-01

    Three-dimensional information is much easier to understand than a set of two-dimensional images. Therefore a layman is thrilled by the pseudo-3D image taken in a scanning electron microscope (SEM) while, when seeing a transmission electron micrograph, his imagination is challenged. First approaches to gain insight in the third dimension were to make serial microtome sections of a region of interest (ROI) and then building a model of the object. Serial microtome sectioning is a tedious and skill-demanding work and therefore seldom done. In the last two decades with the increase of computer power, sophisticated display options, and the development of new instruments, an SEM with a built-in microtome as well as a focused ion beam scanning electron microscope (FIB-SEM), serial sectioning, and 3D analysis has become far easier and faster.Due to the relief like topology of the microtome trimmed block face of resin-embedded tissue, the ROI can be searched in the secondary electron mode, and at the selected spot, the ROI is prepared with the ion beam for 3D analysis. For FIB-SEM tomography, a thin slice is removed with the ion beam and the newly exposed face is imaged with the electron beam, usually by recording the backscattered electrons. The process, also called "slice and view," is repeated until the desired volume is imaged.As FIB-SEM allows 3D imaging of biological fine structure at high resolution of only small volumes, it is crucial to perform slice and view at carefully selected spots. Finding the region of interest is therefore a prerequisite for meaningful imaging. Thin layer plastification of biofilms offers direct access to the original sample surface and allows the selection of an ROI for site-specific FIB-SEM tomography just by its pronounced topographic features.

  2. Model reduction methods for vector autoregressive processes

    CERN Document Server

    Brüggemann, Ralf

    2004-01-01

    1. 1 Objective of the Study Vector autoregressive (VAR) models have become one of the dominant research tools in the analysis of macroeconomic time series during the last two decades. The great success of this modeling class started with Sims' (1980) critique of the traditional simultaneous equation models (SEM). Sims criticized the use of 'too many incredible restrictions' based on 'supposed a priori knowledge' in large scale macroeconometric models which were popular at that time. Therefore, he advo­ cated largely unrestricted reduced form multivariate time series models, unrestricted VAR models in particular. Ever since his influential paper these models have been employed extensively to characterize the underlying dynamics in systems of time series. In particular, tools to summarize the dynamic interaction between the system variables, such as impulse response analysis or forecast error variance decompo­ sitions, have been developed over the years. The econometrics of VAR models and related quantities i...

  3. On the Nature of SEM Estimates of ARMA Parameters.

    Science.gov (United States)

    Hamaker, Ellen L.; Dolan, Conor V.; Molenaar, Peter C. M.

    2002-01-01

    Reexamined the nature of structural equation modeling (SEM) estimates of autoregressive moving average (ARMA) models, replicated the simulation experiments of P. Molenaar, and examined the behavior of the log-likelihood ratio test. Simulation studies indicate that estimates of ARMA parameters observed with SEM software are identical to those…

  4. Methods for testing transport models

    International Nuclear Information System (INIS)

    Singer, C.; Cox, D.

    1991-01-01

    Substantial progress has been made over the past year on six aspects of the work supported by this grant. As a result, we have in hand for the first time a fairly complete set of transport models and improved statistical methods for testing them against large databases. We also have initial results of such tests. These results indicate that careful application of presently available transport theories can reasonably well produce a remarkably wide variety of tokamak data

  5. Secondary emission monitor (SEM) grids.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    A great variety of Secondary Emission Monitors (SEM) are used all over the PS Complex. At other accelerators they are also called wire-grids, harps, etc. They are used to measure beam density profiles (from which beam size and emittance can be derived) in single-pass locations (not on circulating beams). Top left: two individual wire-planes. Top right: a combination of a horizontal and a vertical wire plane. Bottom left: a ribbon grid in its frame, with connecting wires. Bottom right: a SEM-grid with its insertion/retraction mechanism.

  6. Focal adhesion interactions with topographical structures: a novel method for immuno-SEM labelling of focal adhesions in S-phase cells.

    Science.gov (United States)

    Biggs, M J P; Richards, R G; Wilkinson, C D W; Dalby, M J

    2008-07-01

    Current understanding of the mechanisms involved in osseointegration following implantation of a biomaterial has led to adhesion quantification being implemented as an assay of cytocompatibility. Such measurement can be hindered by intra-sample variation owing to morphological changes associated with the cell cycle. Here we report on a new scanning electron microscopical method for the simultaneous immunogold labelling of cellular focal adhesions and S-phase nuclei identified by BrdU incorporation. Prior to labelling, cellular membranes are removed by tritonization and antigens of non-interest blocked by serum incubation. Adhesion plaque-associated vinculin and S-phase nuclei were both separately labelled with a 1.4 nm gold colloid and visualized by subsequent colloid enhancement via silver deposition. This study is specifically concerned with the effects microgroove topographies have on adhesion formation in S-phase osteoblasts. By combining backscattered electron (BSE) imaging with secondary electron (SE) imaging it was possible to visualize S-phase nuclei and the immunogold-labelled adhesion sites in one energy 'plane' and the underlying nanotopography in another. Osteoblast adhesion to these nanotopographies was ascertained by quantification of adhesion complex formation.

  7. Network modelling methods for FMRI.

    Science.gov (United States)

    Smith, Stephen M; Miller, Karla L; Salimi-Khorshidi, Gholamreza; Webster, Matthew; Beckmann, Christian F; Nichols, Thomas E; Ramsey, Joseph D; Woolrich, Mark W

    2011-01-15

    There is great interest in estimating brain "networks" from FMRI data. This is often attempted by identifying a set of functional "nodes" (e.g., spatial ROIs or ICA maps) and then conducting a connectivity analysis between the nodes, based on the FMRI timeseries associated with the nodes. Analysis methods range from very simple measures that consider just two nodes at a time (e.g., correlation between two nodes' timeseries) to sophisticated approaches that consider all nodes simultaneously and estimate one global network model (e.g., Bayes net models). Many different methods are being used in the literature, but almost none has been carefully validated or compared for use on FMRI timeseries data. In this work we generate rich, realistic simulated FMRI data for a wide range of underlying networks, experimental protocols and problematic confounds in the data, in order to compare different connectivity estimation approaches. Our results show that in general correlation-based approaches can be quite successful, methods based on higher-order statistics are less sensitive, and lag-based approaches perform very poorly. More specifically: there are several methods that can give high sensitivity to network connection detection on good quality FMRI data, in particular, partial correlation, regularised inverse covariance estimation and several Bayes net methods; however, accurate estimation of connection directionality is more difficult to achieve, though Patel's τ can be reasonably successful. With respect to the various confounds added to the data, the most striking result was that the use of functionally inaccurate ROIs (when defining the network nodes and extracting their associated timeseries) is extremely damaging to network estimation; hence, results derived from inappropriate ROI definition (such as via structural atlases) should be regarded with great caution. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. SEM: A Cultural Change Agent

    Science.gov (United States)

    Barnes, Bradley; Bourke, Brian

    2015-01-01

    The authors advance the concept that institutional culture is a purposeful framework by which to view SEM's utility, particularly as a cultural change agent. Through the connection of seemingly independent functions of performance and behavior, implications emerge that deepen the understanding of the influence of culture on performance outcomes…

  9. Structural Equations and Causal Explanations: Some Challenges for Causal SEM

    Science.gov (United States)

    Markus, Keith A.

    2010-01-01

    One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete…

  10. SEM-based characterization techniques

    International Nuclear Information System (INIS)

    Russell, P.E.

    1986-01-01

    The scanning electron microscope is now a common instrument in materials characterization laboratories. The basic role of the SEM as a topographic imaging system has steadily been expanding to include a variety of SEM-based analytical techniques. These techniques cover the range of basic semiconductor materials characterization to live-time device characterization of operating LSI or VLSI devices. This paper introduces many of the more commonly used techniques, describes the modifications or additions to a conventional SEM required to utilize the techniques, and gives examples of the use of such techniques. First, the types of signals available from a sample being irradiated by an electron beam are reviewed. Then, where applicable, the type of spectroscopy or microscopy which has evolved to utilize the various signal types are described. This is followed by specific examples of the use of such techniques to solve problems related to semiconductor technology. Techniques emphasized include: x-ray fluorescence spectroscopy, electron beam induced current (EBIC), stroboscopic voltage analysis, cathodoluminescnece and electron beam IC metrology. Current and future trends of some of the these techniques, as related to the semiconductor industry are discussed

  11. The influence of environment temperature on SEM image quality

    International Nuclear Information System (INIS)

    Chen, Li; Liu, Junshan

    2015-01-01

    As the structure dimension goes down to the nano-scale, it often requires a scanning electron microscope (SEM) to provide image magnification up to 100 000  ×. However, SEM images at such a high magnification usually suffer from high resolution value and low signal-to-noise ratio, which results in low quality of the SEM image. In this paper, the quality of the SEM image is improved by optimizing the environment temperature. The experimental results indicate that at 100 000  ×, the quality of the SEM image is influenced by the environment temperature, whereas at 50 000  × it is not. At 100 000  × the best SEM image quality can be achieved from the environment temperature ranging 292 from 294 K, and the SEM image quality evaluated by the double stimulus continuous quality scale method can increase from grade 1 to grade 5. It is expected that this image quality improving method can be used in routine measurements with ordinary SEMs to get high quality images by optimizing the environment temperature. (paper)

  12. International Conference on SEMS 2012

    CERN Document Server

    Liu, Chuang; Scientific explanation and methodology of science; SEMS 2012

    2014-01-01

    This volume contains the contributed papers of invitees to SEMS 2012 who have also given talks at the conference. The invitees are experts in philosophy of science and technology from Asia (besides China), Australia, Europe, Latin America, North America, as well as from within China. The papers in this volume represent the latest work of each researcher in his or her expertise; and as a result, they give a good representation of the cutting-edge researches in diverse areas in different parts of the world.

  13. 3D reconstruction of SEM images by use of optical photogrammetry software.

    Science.gov (United States)

    Eulitz, Mona; Reiss, Gebhard

    2015-08-01

    Reconstruction of the three-dimensional (3D) surface of an object to be examined is widely used for structure analysis in science and many biological questions require information about their true 3D structure. For Scanning Electron Microscopy (SEM) there has been no efficient non-destructive solution for reconstruction of the surface morphology to date. The well-known method of recording stereo pair images generates a 3D stereoscope reconstruction of a section, but not of the complete sample surface. We present a simple and non-destructive method of 3D surface reconstruction from SEM samples based on the principles of optical close range photogrammetry. In optical close range photogrammetry a series of overlapping photos is used to generate a 3D model of the surface of an object. We adapted this method to the special SEM requirements. Instead of moving a detector around the object, the object itself was rotated. A series of overlapping photos was stitched and converted into a 3D model using the software commonly used for optical photogrammetry. A rabbit kidney glomerulus was used to demonstrate the workflow of this adaption. The reconstruction produced a realistic and high-resolution 3D mesh model of the glomerular surface. The study showed that SEM micrographs are suitable for 3D reconstruction by optical photogrammetry. This new approach is a simple and useful method of 3D surface reconstruction and suitable for various applications in research and teaching. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Analytical methods used at model facility

    International Nuclear Information System (INIS)

    Wing, N.S.

    1984-01-01

    A description of analytical methods used at the model LEU Fuel Fabrication Facility is presented. The methods include gravimetric uranium analysis, isotopic analysis, fluorimetric analysis, and emission spectroscopy

  15. Social Context, Self-Perceptions and Student Engagement: A SEM Investigation of the Self-System Model of Motivational Development (SSMMD)

    Science.gov (United States)

    Dupont, Serge; Galand, Benoit; Nils, Frédéric; Hospel, Virginie

    2014-01-01

    Introduction: The present study aimed to test a theoretically-based model (the self-system model of motivational development) including at the same time the extent to which the social context provides structure, warmth and autonomy support, the students' perceived autonomy, relatedness and competence, and behavioral, cognitive and emotional…

  16. Quantitative approach on SEM images of microstructure of clay soils

    Institute of Scientific and Technical Information of China (English)

    施斌; 李生林; M.Tolkachev

    1995-01-01

    The working principles of Videolab Image Processing System (VIPS), the examining methods of orientation of microstructural units of clay soils and analysing results on SEM images of some typical microstructures of clay soils using the VIPS are introduced.

  17. DETECTION OF DELAMINATION IN A COMPOSITE PLATE BY SEM

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A numerical method of integration of Green's functi ons of strip element method (SEM) is proposed. The response of ultrasonic sourc e generated by a transducer on the surface of a multi-ply composite plate conta ining a delamination is analyzed by the use of SEM. The numerical results show that the scanning features of the ultrasonic waves may be used to identify the d elamination inside the composite plate .

  18. A methodological basis for SEM autoradiography: biosynthesis and radioligand binding

    International Nuclear Information System (INIS)

    Cheng, G.; Hodges, G.M.; Trejdosiewicz, L.K.

    1985-01-01

    A method is described for scanning electron microscope (SEM) autoradiography whereby preservation of high resolution cell surface details is retained together with degelatination of the emulsion without gross loss or redistribution of silver grains. This method should provide a convenient medium-sized marker for SEM (using secondary, backscattered electron and X-ray imaging) topographic studies of biosynthesized molecules, and of cell surface receptors and antigens, using indirect or direct labelling procedures with radio-labelled ligands. (author)

  19. Assessment of engineered surfaces roughness by high-resolution 3D SEM photogrammetry

    Energy Technology Data Exchange (ETDEWEB)

    Gontard, L.C., E-mail: lionelcg@gmail.com [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, Puerto Real 11510 (Spain); López-Castro, J.D.; González-Rovira, L. [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Escuela Superior de Ingeniería, Laboratorio de Corrosión, Universidad de Cádiz, Puerto Real 11519 (Spain); Vázquez-Martínez, J.M. [Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, Universidad de Cádiz, Puerto Real 11519 (Spain); Varela-Feria, F.M. [Servicio de Microscopía Centro de Investigación, Tecnología e Innovación (CITIUS), Universidad de Sevilla, Av. Reina Mercedes 4b, 41012 Sevilla (Spain); Marcos, M. [Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, Universidad de Cádiz, Puerto Real 11519 (Spain); and others

    2017-06-15

    Highlights: • We describe a method to acquire a high-angle tilt series of SEM images that is symmetrical respect to the zero tilt of the sample stage. The method can be applied in any SEM microscope. • Using the method, high-resolution 3D SEM photogrammetry can be applied on planar surfaces. • 3D models of three surfaces patterned with grooves are reconstructed with high resolution using multi-view freeware photogrammetry software as described in LC Gontard et al. Ultramicroscopy, 2016. • From the 3D models roughness parameters are measured • 3D SEM high-resolution photogrammetry is compared with two conventional methods used for roughness characetrization: stereophotogrammetry and contact profilometry. • It provides three-dimensional information with high-resolution that is out of reach for any other metrological technique. - Abstract: We describe a methodology to obtain three-dimensional models of engineered surfaces using scanning electron microscopy and multi-view photogrammetry (3DSEM). For the reconstruction of the 3D models of the surfaces we used freeware available in the cloud. The method was applied to study the surface roughness of metallic samples patterned with parallel grooves by means of laser. The results are compared with measurements obtained using stylus profilometry (PR) and SEM stereo-photogrammetry (SP). The application of 3DSEM is more time demanding than PR or SP, but it provides a more accurate representation of the surfaces. The results obtained with the three techniques are compared by investigating the influence of sampling step on roughness parameters.

  20. Energy models: methods and trends

    Energy Technology Data Exchange (ETDEWEB)

    Reuter, A [Division of Energy Management and Planning, Verbundplan, Klagenfurt (Austria); Kuehner, R [IER Institute for Energy Economics and the Rational Use of Energy, University of Stuttgart, Stuttgart (Germany); Wohlgemuth, N [Department of Economy, University of Klagenfurt, Klagenfurt (Austria)

    1997-12-31

    Energy environmental and economical systems do not allow for experimentation since this would be dangerous, too expensive or even impossible. Instead, mathematical models are applied for energy planning. Experimenting is replaced by varying the structure and some parameters of `energy models`, computing the values of depending parameters, comparing variations, and interpreting their outcomings. Energy models are as old as computers. In this article the major new developments in energy modeling will be pointed out. We distinguish between 3 reasons of new developments: progress in computer technology, methodological progress and novel tasks of energy system analysis and planning. 2 figs., 19 refs.

  1. Energy models: methods and trends

    International Nuclear Information System (INIS)

    Reuter, A.; Kuehner, R.; Wohlgemuth, N.

    1996-01-01

    Energy environmental and economical systems do not allow for experimentation since this would be dangerous, too expensive or even impossible. Instead, mathematical models are applied for energy planning. Experimenting is replaced by varying the structure and some parameters of 'energy models', computing the values of depending parameters, comparing variations, and interpreting their outcomings. Energy models are as old as computers. In this article the major new developments in energy modeling will be pointed out. We distinguish between 3 reasons of new developments: progress in computer technology, methodological progress and novel tasks of energy system analysis and planning

  2. A Structural Equation Model (SEM) of the Impact of Transformational, Visionary, Charismatic and Ethical Leadership Styles on the Development of Wise Leadership among Filipino Private Secondary School Principals

    Science.gov (United States)

    Parco-Tropicales, Marishirl; de Guzman, Allan B.

    2014-01-01

    In recent years, wisdom is seen as a key resource for school leaders in dealing with the dynamics of the changing school environments. This study purports to expand the growing interest on wisdom by testing a model that describes the impact of transformational, visionary, charismatic and ethical leadership styles on wise leadership development…

  3. Exploring the Association between Transformational Leadership and Teacher's Self-Efficacy in Greek Education System: A Multilevel SEM Model

    Science.gov (United States)

    Gkolia, Aikaterini; Koustelios, Athanasios; Belias, Dimitrios

    2018-01-01

    The main aim of this study is to examine the effect of principals' transformational leadership on teachers' self-efficacy across 77 different Greek elementary and secondary schools based on a centralized education system. For the investigation of the above effect multilevel Structural Equation Modelling analysis was conducted, recognizing the…

  4. Candidate Prediction Models and Methods

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg; Nielsen, Torben Skov; Madsen, Henrik

    2005-01-01

    This document lists candidate prediction models for Work Package 3 (WP3) of the PSO-project called ``Intelligent wind power prediction systems'' (FU4101). The main focus is on the models transforming numerical weather predictions into predictions of power production. The document also outlines...... the possibilities w.r.t. different numerical weather predictions actually available to the project....

  5. Moderators, mediators, and bidirectional relationships in the International Classification of Functioning, Disability and Health (ICF) framework: An empirical investigation using a longitudinal design and Structural Equation Modeling (SEM).

    Science.gov (United States)

    Rouquette, Alexandra; Badley, Elizabeth M; Falissard, Bruno; Dub, Timothée; Leplege, Alain; Coste, Joël

    2015-06-01

    The International Classification of Functioning, Disability and Health (ICF) published in 2001 describes the consequences of health conditions with three components of impairments in body structures or functions, activity limitations and participation restrictions. Two of the new features of the conceptual model were the possibility of feedback effects between each ICF component and the introduction of contextual factors conceptualized as moderators of the relationship between the components. The aim of this longitudinal study is to provide empirical evidence of these two kinds of effect. Structural equation modeling was used to analyze data from a French population-based cohort of 548 patients with knee osteoarthritis recruited between April 2007 and March 2009 and followed for three years. Indicators of the body structure and function, activity and participation components of the ICF were derived from self-administered standardized instruments. The measurement model revealed four separate factors for body structures impairments, body functions impairments, activity limitations and participation restrictions. The classic sequence from body impairments to participation restrictions through activity limitations was found at each assessment time. Longitudinal study of the ICF component relationships showed a feedback pathway indicating that the level of participation restrictions at baseline was predictive of activity limitations three years later. Finally, the moderating role of personal (age, sex, mental health, etc.) and environmental factors (family relationships, mobility device use, etc.) was investigated. Three contextual factors (sex, family relationships and walking stick use) were found to be moderators for the relationship between the body impairments and the activity limitations components. Mental health was found to be a mediating factor of the effect of activity limitations on participation restrictions. Copyright © 2015 Elsevier Ltd. All rights

  6. Multiple-Group Analysis Using the sem Package in the R System

    Science.gov (United States)

    Evermann, Joerg

    2010-01-01

    Multiple-group analysis in covariance-based structural equation modeling (SEM) is an important technique to ensure the invariance of latent construct measurements and the validity of theoretical models across different subpopulations. However, not all SEM software packages provide multiple-group analysis capabilities. The sem package for the R…

  7. Automated CD-SEM metrology for efficient TD and HVM

    Science.gov (United States)

    Starikov, Alexander; Mulapudi, Satya P.

    2008-03-01

    CD-SEM is the metrology tool of choice for patterning process development and production process control. We can make these applications more efficient by extracting more information from each CD-SEM image. This enables direct monitors of key process parameters, such as lithography dose and focus, or predicting the outcome of processing, such as etched dimensions or electrical parameters. Automating CD-SEM recipes at the early stages of process development can accelerate technology characterization, segmentation of variance and process improvements. This leverages the engineering effort, reduces development costs and helps to manage the risks inherent in new technology. Automating CD-SEM for manufacturing enables efficient operations. Novel SEM Alarm Time Indicator (SATI) makes this task manageable. SATI pulls together data mining, trend charting of the key recipe and Operations (OPS) indicators, Pareto of OPS losses and inputs for root cause analysis. This approach proved natural to our FAB personnel. After minimal initial training, we applied new methods in 65nm FLASH manufacture. This resulted in significant lasting improvements of CD-SEM recipe robustness, portability and automation, increased CD-SEM capacity and MT productivity.

  8. In Situ Characterization of Boehmite Particles in Water Using Liquid SEM.

    Science.gov (United States)

    Yao, Juan; Arey, Bruce W; Yang, Li; Zhang, Fei; Komorek, Rachel; Chun, Jaehun; Yu, Xiao-Ying

    2017-09-27

    In situ imaging and elemental analysis of boehmite (AlOOH) particles in water is realized using the System for Analysis at the Liquid Vacuum Interface (SALVI) and Scanning Electron Microscopy (SEM). This paper describes the method and key steps in integrating the vacuum compatible SAVLI to SEM and obtaining secondary electron (SE) images of particles in liquid in high vacuum. Energy dispersive x-ray spectroscopy (EDX) is used to obtain elemental analysis of particles in liquid and control samples including deionized (DI) water only and an empty channel as well. Synthesized boehmite (AlOOH) particles suspended in liquid are used as a model in the liquid SEM illustration. The results demonstrate that the particles can be imaged in the SE mode with good resolution (i.e., 400 nm). The AlOOH EDX spectrum shows significant signal from the aluminum (Al) when compared with the DI water and the empty channel control. In situ liquid SEM is a powerful technique to study particles in liquid with many exciting applications. This procedure aims to provide technical know-how in order to conduct liquid SEM imaging and EDX analysis using SALVI and to reduce potential pitfalls when using this approach.

  9. 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.

  10. Computer-Aided Modelling Methods and Tools

    DEFF Research Database (Denmark)

    Cameron, Ian; Gani, Rafiqul

    2011-01-01

    The development of models for a range of applications requires methods and tools. In many cases a reference model is required that allows the generation of application specific models that are fit for purpose. There are a range of computer aided modelling tools available that help to define the m...

  11. A business case method for business models

    OpenAIRE

    Meertens, Lucas Onno; Starreveld, E.; Iacob, Maria Eugenia; Nieuwenhuis, Lambertus Johannes Maria; Shishkov, Boris

    2013-01-01

    Intuitively, business cases and business models are closely connected. However, a thorough literature review revealed no research on the combination of them. Besides that, little is written on the evaluation of business models at all. This makes it difficult to compare different business model alternatives and choose the best one. In this article, we develop a business case method to objectively compare business models. It is an eight-step method, starting with business drivers and ending wit...

  12. Mechatronic Systems Design Methods, Models, Concepts

    CERN Document Server

    Janschek, Klaus

    2012-01-01

    In this textbook, fundamental methods for model-based design of mechatronic systems are presented in a systematic, comprehensive form. The method framework presented here comprises domain-neutral methods for modeling and performance analysis: multi-domain modeling (energy/port/signal-based), simulation (ODE/DAE/hybrid systems), robust control methods, stochastic dynamic analysis, and quantitative evaluation of designs using system budgets. The model framework is composed of analytical dynamic models for important physical and technical domains of realization of mechatronic functions, such as multibody dynamics, digital information processing and electromechanical transducers. Building on the modeling concept of a technology-independent generic mechatronic transducer, concrete formulations for electrostatic, piezoelectric, electromagnetic, and electrodynamic transducers are presented. More than 50 fully worked out design examples clearly illustrate these methods and concepts and enable independent study of th...

  13. Element-by-element parallel spectral-element methods for 3-D teleseismic wave modeling

    KAUST Repository

    Liu, Shaolin

    2017-09-28

    The development of an efficient algorithm for teleseismic wave field modeling is valuable for calculating the gradients of the misfit function (termed misfit gradients) or Fréchet derivatives when the teleseismic waveform is used for adjoint tomography. Here, we introduce an element-by-element parallel spectral-element method (EBE-SEM) for the efficient modeling of teleseismic wave field propagation in a reduced geology model. Under the plane-wave assumption, the frequency-wavenumber (FK) technique is implemented to compute the boundary wave field used to construct the boundary condition of the teleseismic wave incidence. To reduce the memory required for the storage of the boundary wave field for the incidence boundary condition, a strategy is introduced to efficiently store the boundary wave field on the model boundary. The perfectly matched layers absorbing boundary condition (PML ABC) is formulated using the EBE-SEM to absorb the scattered wave field from the model interior. The misfit gradient can easily be constructed in each time step during the calculation of the adjoint wave field. Three synthetic examples demonstrate the validity of the EBE-SEM for use in teleseismic wave field modeling and the misfit gradient calculation.

  14. Coherence method of identifying signal noise model

    International Nuclear Information System (INIS)

    Vavrin, J.

    1981-01-01

    The noise analysis method is discussed in identifying perturbance models and their parameters by a stochastic analysis of the noise model of variables measured on a reactor. The analysis of correlations is made in the frequency region using coherence analysis methods. In identifying an actual specific perturbance, its model should be determined and recognized in a compound model of the perturbance system using the results of observation. The determination of the optimum estimate of the perturbance system model is based on estimates of related spectral densities which are determined from the spectral density matrix of the measured variables. Partial and multiple coherence, partial transfers, the power spectral densities of the input and output variables of the noise model are determined from the related spectral densities. The possibilities of applying the coherence identification methods were tested on a simple case of a simulated stochastic system. Good agreement was found of the initial analytic frequency filters and the transfers identified. (B.S.)

  15. Model Uncertainty Quantification Methods In Data Assimilation

    Science.gov (United States)

    Pathiraja, S. D.; Marshall, L. A.; Sharma, A.; Moradkhani, H.

    2017-12-01

    Data Assimilation involves utilising observations to improve model predictions in a seamless and statistically optimal fashion. Its applications are wide-ranging; from improving weather forecasts to tracking targets such as in the Apollo 11 mission. The use of Data Assimilation methods in high dimensional complex geophysical systems is an active area of research, where there exists many opportunities to enhance existing methodologies. One of the central challenges is in model uncertainty quantification; the outcome of any Data Assimilation study is strongly dependent on the uncertainties assigned to both observations and models. I focus on developing improved model uncertainty quantification methods that are applicable to challenging real world scenarios. These include developing methods for cases where the system states are only partially observed, where there is little prior knowledge of the model errors, and where the model error statistics are likely to be highly non-Gaussian.

  16. A Method for Model Checking Feature Interactions

    DEFF Research Database (Denmark)

    Pedersen, Thomas; Le Guilly, Thibaut; Ravn, Anders Peter

    2015-01-01

    This paper presents a method to check for feature interactions in a system assembled from independently developed concurrent processes as found in many reactive systems. The method combines and refines existing definitions and adds a set of activities. The activities describe how to populate the ...... the definitions with models to ensure that all interactions are captured. The method is illustrated on a home automation example with model checking as analysis tool. In particular, the modelling formalism is timed automata and the analysis uses UPPAAL to find interactions....

  17. Numerical methods and modelling for engineering

    CERN Document Server

    Khoury, Richard

    2016-01-01

    This textbook provides a step-by-step approach to numerical methods in engineering modelling. The authors provide a consistent treatment of the topic, from the ground up, to reinforce for students that numerical methods are a set of mathematical modelling tools which allow engineers to represent real-world systems and compute features of these systems with a predictable error rate. Each method presented addresses a specific type of problem, namely root-finding, optimization, integral, derivative, initial value problem, or boundary value problem, and each one encompasses a set of algorithms to solve the problem given some information and to a known error bound. The authors demonstrate that after developing a proper model and understanding of the engineering situation they are working on, engineers can break down a model into a set of specific mathematical problems, and then implement the appropriate numerical methods to solve these problems. Uses a “building-block” approach, starting with simpler mathemati...

  18. Review of various dynamic modeling methods and development of an intuitive modeling method for dynamic systems

    International Nuclear Information System (INIS)

    Shin, Seung Ki; Seong, Poong Hyun

    2008-01-01

    Conventional static reliability analysis methods are inadequate for modeling dynamic interactions between components of a system. Various techniques such as dynamic fault tree, dynamic Bayesian networks, and dynamic reliability block diagrams have been proposed for modeling dynamic systems based on improvement of the conventional modeling methods. In this paper, we review these methods briefly and introduce dynamic nodes to the existing Reliability Graph with General Gates (RGGG) as an intuitive modeling method to model dynamic systems. For a quantitative analysis, we use a discrete-time method to convert an RGGG to an equivalent Bayesian network and develop a software tool for generation of probability tables

  19. Probability-of-Superiority SEM (PS-SEM—Detecting Probability-Based Multivariate Relationships in Behavioral Research

    Directory of Open Access Journals (Sweden)

    Johnson Ching-Hong Li

    2018-06-01

    Full Text Available In behavioral research, exploring bivariate relationships between variables X and Y based on the concept of probability-of-superiority (PS has received increasing attention. Unlike the conventional, linear-based bivariate relationship (e.g., Pearson's correlation, PS defines that X and Y can be related based on their likelihood—e.g., a student who is above mean in SAT has 63% likelihood of achieving an above-mean college GPA. Despite its increasing attention, the concept of PS is restricted to a simple bivariate scenario (X-Y pair, which hinders the development and application of PS in popular multivariate modeling such as structural equation modeling (SEM. Therefore, this study addresses an empirical-based simulation study that explores the potential of detecting PS-based relationship in SEM, called PS-SEM. The simulation results showed that the proposed PS-SEM method can detect and identify PS-based when data follow PS-based relationships, thereby providing a useful method for researchers to explore PS-based SEM in their studies. Conclusions, implications, and future directions based on the findings are also discussed.

  20. Geostatistical methods applied to field model residuals

    DEFF Research Database (Denmark)

    Maule, Fox; Mosegaard, K.; Olsen, Nils

    consists of measurement errors and unmodelled signal), and is typically assumed to be uncorrelated and Gaussian distributed. We have applied geostatistical methods to analyse the residuals of the Oersted(09d/04) field model [http://www.dsri.dk/Oersted/Field_models/IGRF_2005_candidates/], which is based...

  1. Modeling complex work systems - method meets reality

    NARCIS (Netherlands)

    van der Veer, Gerrit C.; Hoeve, Machteld; Lenting, Bert

    1996-01-01

    Modeling an existing task situation is often a first phase in the (re)design of information systems. For complex systems design, this model should consider both the people and the organization involved, the work, and situational aspects. Groupware Task Analysis (GTA) as part of a method for the

  2. Cache memory modelling method and system

    OpenAIRE

    Posadas Cobo, Héctor; Villar Bonet, Eugenio; Díaz Suárez, Luis

    2011-01-01

    The invention relates to a method for modelling a data cache memory of a destination processor, in order to simulate the behaviour of said data cache memory during the execution of a software code on a platform comprising said destination processor. According to the invention, the simulation is performed on a native platform having a processor different from the destination processor comprising the aforementioned data cache memory to be modelled, said modelling being performed by means of the...

  3. A survey of real face modeling methods

    Science.gov (United States)

    Liu, Xiaoyue; Dai, Yugang; He, Xiangzhen; Wan, Fucheng

    2017-09-01

    The face model has always been a research challenge in computer graphics, which involves the coordination of multiple organs in faces. This article explained two kinds of face modeling method which is based on the data driven and based on parameter control, analyzed its content and background, summarized their advantages and disadvantages, and concluded muscle model which is based on the anatomy of the principle has higher veracity and easy to drive.

  4. Sparsity-Based Super Resolution for SEM Images.

    Science.gov (United States)

    Tsiper, Shahar; Dicker, Or; Kaizerman, Idan; Zohar, Zeev; Segev, Mordechai; Eldar, Yonina C

    2017-09-13

    The scanning electron microscope (SEM) is an electron microscope that produces an image of a sample by scanning it with a focused beam of electrons. The electrons interact with the atoms in the sample, which emit secondary electrons that contain information about the surface topography and composition. The sample is scanned by the electron beam point by point, until an image of the surface is formed. Since its invention in 1942, the capabilities of SEMs have become paramount in the discovery and understanding of the nanometer world, and today it is extensively used for both research and in industry. In principle, SEMs can achieve resolution better than one nanometer. However, for many applications, working at subnanometer resolution implies an exceedingly large number of scanning points. For exactly this reason, the SEM diagnostics of microelectronic chips is performed either at high resolution (HR) over a small area or at low resolution (LR) while capturing a larger portion of the chip. Here, we employ sparse coding and dictionary learning to algorithmically enhance low-resolution SEM images of microelectronic chips-up to the level of the HR images acquired by slow SEM scans, while considerably reducing the noise. Our methodology consists of two steps: an offline stage of learning a joint dictionary from a sequence of LR and HR images of the same region in the chip, followed by a fast-online super-resolution step where the resolution of a new LR image is enhanced. We provide several examples with typical chips used in the microelectronics industry, as well as a statistical study on arbitrary images with characteristic structural features. Conceptually, our method works well when the images have similar characteristics, as microelectronics chips do. This work demonstrates that employing sparsity concepts can greatly improve the performance of SEM, thereby considerably increasing the scanning throughput without compromising on analysis quality and resolution.

  5. Constructive Epistemic Modeling: A Hierarchical Bayesian Model Averaging Method

    Science.gov (United States)

    Tsai, F. T. C.; Elshall, A. S.

    2014-12-01

    Constructive epistemic modeling is the idea that our understanding of a natural system through a scientific model is a mental construct that continually develops through learning about and from the model. Using the hierarchical Bayesian model averaging (HBMA) method [1], this study shows that segregating different uncertain model components through a BMA tree of posterior model probabilities, model prediction, within-model variance, between-model variance and total model variance serves as a learning tool [2]. First, the BMA tree of posterior model probabilities permits the comparative evaluation of the candidate propositions of each uncertain model component. Second, systemic model dissection is imperative for understanding the individual contribution of each uncertain model component to the model prediction and variance. Third, the hierarchical representation of the between-model variance facilitates the prioritization of the contribution of each uncertain model component to the overall model uncertainty. We illustrate these concepts using the groundwater modeling of a siliciclastic aquifer-fault system. The sources of uncertainty considered are from geological architecture, formation dip, boundary conditions and model parameters. The study shows that the HBMA analysis helps in advancing knowledge about the model rather than forcing the model to fit a particularly understanding or merely averaging several candidate models. [1] Tsai, F. T.-C., and A. S. Elshall (2013), Hierarchical Bayesian model averaging for hydrostratigraphic modeling: Uncertainty segregation and comparative evaluation. Water Resources Research, 49, 5520-5536, doi:10.1002/wrcr.20428. [2] Elshall, A.S., and F. T.-C. Tsai (2014). Constructive epistemic modeling of groundwater flow with geological architecture and boundary condition uncertainty under Bayesian paradigm, Journal of Hydrology, 517, 105-119, doi: 10.1016/j.jhydrol.2014.05.027.

  6. Accurate Modeling Method for Cu Interconnect

    Science.gov (United States)

    Yamada, Kenta; Kitahara, Hiroshi; Asai, Yoshihiko; Sakamoto, Hideo; Okada, Norio; Yasuda, Makoto; Oda, Noriaki; Sakurai, Michio; Hiroi, Masayuki; Takewaki, Toshiyuki; Ohnishi, Sadayuki; Iguchi, Manabu; Minda, Hiroyasu; Suzuki, Mieko

    This paper proposes an accurate modeling method of the copper interconnect cross-section in which the width and thickness dependence on layout patterns and density caused by processes (CMP, etching, sputtering, lithography, and so on) are fully, incorporated and universally expressed. In addition, we have developed specific test patterns for the model parameters extraction, and an efficient extraction flow. We have extracted the model parameters for 0.15μm CMOS using this method and confirmed that 10%τpd error normally observed with conventional LPE (Layout Parameters Extraction) was completely dissolved. Moreover, it is verified that the model can be applied to more advanced technologies (90nm, 65nm and 55nm CMOS). Since the interconnect delay variations due to the processes constitute a significant part of what have conventionally been treated as random variations, use of the proposed model could enable one to greatly narrow the guardbands required to guarantee a desired yield, thereby facilitating design closure.

  7. SEM facility for examination of reactive and radioactive materials

    International Nuclear Information System (INIS)

    Downs, G.L.; Tucker, P.A.

    1977-01-01

    A scanning electron microscope (SEM) facility for the examination of tritium-containing materials is operational at Mound Laboratory. The SEM is installed with the sample chamber incorporated as an integral part of an inert gas glovebox facility to enable easy handling of radioactive and pyrophoric materials. A standard SEM (ETEC Model B-1) was modified to meet dimensional, operational, and safety-related requirements. a glovebox was designed and fabricated which permitted access with the gloves to all parts of the SEM sample chamber to facilitate director and accessory replacement and repairs. A separate console combining the electron optical column and specimen chamber was interfaced to the glovebox by a custom-made, neoprene bellows so that the vibrations normally associated with the blowers and pumps were damped. Photomicrographs of tritiated pyrophoric materials show the usefulness of this facility. Some of the difficulties involved in the investigation of these materials are also discussed. The SEM is also equipped with an energy dispersive x-ray detector (ORTEC) and a Secondary Ion Mass Spectrometer (3M) attachments. This latter attachment allows analysis of secondary ions with masses ranging from 1-300 amu. (Auth.)

  8. Recent advances in 3D SEM surface reconstruction.

    Science.gov (United States)

    Tafti, Ahmad P; Kirkpatrick, Andrew B; Alavi, Zahrasadat; Owen, Heather A; Yu, Zeyun

    2015-11-01

    The scanning electron microscope (SEM), as one of the most commonly used instruments in biology and material sciences, employs electrons instead of light to determine the surface properties of specimens. However, the SEM micrographs still remain 2D images. To effectively measure and visualize the surface attributes, we need to restore the 3D shape model from the SEM images. 3D surface reconstruction is a longstanding topic in microscopy vision as it offers quantitative and visual information for a variety of applications consisting medicine, pharmacology, chemistry, and mechanics. In this paper, we attempt to explain the expanding body of the work in this area, including a discussion of recent techniques and algorithms. With the present work, we also enhance the reliability, accuracy, and speed of 3D SEM surface reconstruction by designing and developing an optimized multi-view framework. We then consider several real-world experiments as well as synthetic data to examine the qualitative and quantitative attributes of our proposed framework. Furthermore, we present a taxonomy of 3D SEM surface reconstruction approaches and address several challenging issues as part of our future work. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. SEM probe of IC radiation sensitivity

    Science.gov (United States)

    Gauthier, M. K.; Stanley, A. G.

    1979-01-01

    Scanning Electron Microscope (SEM) used to irradiate single integrated circuit (IC) subcomponent to test for radiation sensitivity can localize area of IC less than .03 by .03 mm for determination of exact location of radiation sensitive section.

  10. Measuring topographies from conventional SEM acquisitions.

    Science.gov (United States)

    Shi, Qiwei; Roux, Stéphane; Latourte, Félix; Hild, François; Loisnard, Dominique; Brynaert, Nicolas

    2018-04-27

    The present study extends the stereoscopic imaging principle for estimating the surface topography to two orientations, namely, normal to the electron beam axis and inclined at 70° as suited for EBSD analyses. In spite of the large angle difference, it is shown that the topography can be accurately determined using regularized global Digital Image Correlation. The surface topography is compared to another estimate issued from a 3D FIB-SEM procedure where the sample surface is first covered by a Pt layer, and its initial topography is progressively revealed from successive FIB-milling. These two methods are successfully compared on a 6% strained steel specimen in an in situ mechanical test. This analysis is supplemented by a third approach estimating the change of topography from crystal rotations as measured from successive EBSD images. This last technique ignores plastic deformation, and thus only holds in an elastic regime. For the studied example, despite the large plastic flow, it is shown that crystal rotation already accounts for a significant part of the deformation-induced topography. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Global Optimization Ensemble Model for Classification Methods

    Science.gov (United States)

    Anwar, Hina; Qamar, Usman; Muzaffar Qureshi, Abdul Wahab

    2014-01-01

    Supervised learning is the process of data mining for deducing rules from training datasets. A broad array of supervised learning algorithms exists, every one of them with its own advantages and drawbacks. There are some basic issues that affect the accuracy of classifier while solving a supervised learning problem, like bias-variance tradeoff, dimensionality of input space, and noise in the input data space. All these problems affect the accuracy of classifier and are the reason that there is no global optimal method for classification. There is not any generalized improvement method that can increase the accuracy of any classifier while addressing all the problems stated above. This paper proposes a global optimization ensemble model for classification methods (GMC) that can improve the overall accuracy for supervised learning problems. The experimental results on various public datasets showed that the proposed model improved the accuracy of the classification models from 1% to 30% depending upon the algorithm complexity. PMID:24883382

  12. Global Optimization Ensemble Model for Classification Methods

    Directory of Open Access Journals (Sweden)

    Hina Anwar

    2014-01-01

    Full Text Available Supervised learning is the process of data mining for deducing rules from training datasets. A broad array of supervised learning algorithms exists, every one of them with its own advantages and drawbacks. There are some basic issues that affect the accuracy of classifier while solving a supervised learning problem, like bias-variance tradeoff, dimensionality of input space, and noise in the input data space. All these problems affect the accuracy of classifier and are the reason that there is no global optimal method for classification. There is not any generalized improvement method that can increase the accuracy of any classifier while addressing all the problems stated above. This paper proposes a global optimization ensemble model for classification methods (GMC that can improve the overall accuracy for supervised learning problems. The experimental results on various public datasets showed that the proposed model improved the accuracy of the classification models from 1% to 30% depending upon the algorithm complexity.

  13. Simulation of FIB-SEM images for analysis of porous microstructures.

    Science.gov (United States)

    Prill, Torben; Schladitz, Katja

    2013-01-01

    Focused ion beam nanotomography-scanning electron microscopy tomography yields high-quality three-dimensional images of materials microstructures at the nanometer scale combining serial sectioning using a focused ion beam with SEM. However, FIB-SEM tomography of highly porous media leads to shine-through artifacts preventing automatic segmentation of the solid component. We simulate the SEM process in order to generate synthetic FIB-SEM image data for developing and validating segmentation methods. Monte-Carlo techniques yield accurate results, but are too slow for the simulation of FIB-SEM tomography requiring hundreds of SEM images for one dataset alone. Nevertheless, a quasi-analytic description of the specimen and various acceleration techniques, including a track compression algorithm and an acceleration for the simulation of secondary electrons, cut down the computing time by orders of magnitude, allowing for the first time to simulate FIB-SEM tomography. © Wiley Periodicals, Inc.

  14. Modelling methods for milk intake measurements

    International Nuclear Information System (INIS)

    Coward, W.A.

    1999-01-01

    One component of the first Research Coordination Programme was a tutorial session on modelling in in-vivo tracer kinetic methods. This section describes the principles that are involved and how these can be translated into spreadsheets using Microsoft Excel and the SOLVER function to fit the model to the data. The purpose of this section is to describe the system developed within the RCM, and how it is used

  15. Calibração de um modelo de umidade para um solo aluvial sem cobertura vegetal Calibration of a soil moisture model for an alluvial soil without vegetable cover

    Directory of Open Access Journals (Sweden)

    Eduardo C. B. de Araújo

    2001-12-01

    Full Text Available O presente trabalho foi conduzido na região semi-árida em solo aluvial eutrófico, em área irrigada da Fazenda Experimental Vale do Curu, pertencente à Universidade Federal do Ceará. O experimento se desenvolveu no período de 4/10/99 a 10/3/00, mantendo-se o solo sem vegetação, com objetivo de calibrar o modelo de umidade do solo para atividades agrícolas (MUSAG e determinar os parâmetros associados às funções que compõem o modelo (infiltração, percolação e evaporação. A calibração consistiu em se medir a umidade no solo, na profundidade de 0 a 0,30 m, com uma sonda de nêutrons, e comparar essas medidas com a umidade no solo estimada pelo modelo parametrizado. O MUSAG permitiu valores estimados de armazenamento hídrico, estatisticamente não diferentes dos valores determinados pela sonda de nêutrons para a profundidade de 0 - 0,30 m. O modelo apresentou resultado menos satisfatório para estimativa da umidade em períodos com maior freqüência de precipitação, seguindo a tendência dos valores observados, porém subestimando-os.This work was carried out at the Experimental Farm of the Universidade Federal do Ceará, Curu River Valley, in the State of Ceará, Brazil, from October 4, 1999 to March 10, 2000, to calibrate, under field conditions, the so called soil moisture model for agricultural activities (MUSAG determining the parameters associated to the model functions (infiltration, percolation and evaporation.The measurements of soil water storage were done with a neutron probe, and compared with that predicted by the model. The MUSAG provided values of storage water, statistically not different from the values determined by the neutron probe for the depth of 0 - 0,30 m. The model did not provide reasonable estimates of the soil moisture during periods with larger precipitation frequency, however, the predictions followed the tendency of the observed values, but underestimating them.

  16. Diffuse interface methods for multiphase flow modeling

    International Nuclear Information System (INIS)

    Jamet, D.

    2004-01-01

    Full text of publication follows:Nuclear reactor safety programs need to get a better description of some stages of identified incident or accident scenarios. For some of them, such as the reflooding of the core or the dryout of fuel rods, the heat, momentum and mass transfers taking place at the scale of droplets or bubbles are part of the key physical phenomena for which a better description is needed. Experiments are difficult to perform at these very small scales and direct numerical simulations is viewed as a promising way to give new insight into these complex two-phase flows. This type of simulations requires numerical methods that are accurate, efficient and easy to run in three space dimensions and on parallel computers. Despite many years of development, direct numerical simulation of two-phase flows is still very challenging, mostly because it requires solving moving boundary problems. To avoid this major difficulty, a new class of numerical methods is arising, called diffuse interface methods. These methods are based on physical theories dating back to van der Waals and mostly used in materials science. In these methods, interfaces separating two phases are modeled as continuous transitions zones instead of surfaces of discontinuity. Since all the physical variables encounter possibly strong but nevertheless always continuous variations across the interfacial zones, these methods virtually eliminate the difficult moving boundary problem. We show that these methods lead to a single-phase like system of equations, which makes it easier to code in 3D and to make parallel compared to more classical methods. The first method presented is dedicated to liquid-vapor flows with phase-change. It is based on the van der Waals' theory of capillarity. This method has been used to study nucleate boiling of a pure fluid and of dilute binary mixtures. We discuss the importance of the choice and the meaning of the order parameter, i.e. a scalar which discriminates one

  17. Model-Based Method for Sensor Validation

    Science.gov (United States)

    Vatan, Farrokh

    2012-01-01

    Fault detection, diagnosis, and prognosis are essential tasks in the operation of autonomous spacecraft, instruments, and in situ platforms. One of NASA s key mission requirements is robust state estimation. Sensing, using a wide range of sensors and sensor fusion approaches, plays a central role in robust state estimation, and there is a need to diagnose sensor failure as well as component failure. Sensor validation can be considered to be part of the larger effort of improving reliability and safety. The standard methods for solving the sensor validation problem are based on probabilistic analysis of the system, from which the method based on Bayesian networks is most popular. Therefore, these methods can only predict the most probable faulty sensors, which are subject to the initial probabilities defined for the failures. The method developed in this work is based on a model-based approach and provides the faulty sensors (if any), which can be logically inferred from the model of the system and the sensor readings (observations). The method is also more suitable for the systems when it is hard, or even impossible, to find the probability functions of the system. The method starts by a new mathematical description of the problem and develops a very efficient and systematic algorithm for its solution. The method builds on the concepts of analytical redundant relations (ARRs).

  18. Fuzzy Control and Connected Region Marking Algorithm-Based SEM Nanomanipulation

    Directory of Open Access Journals (Sweden)

    Dongjie Li

    2012-01-01

    Full Text Available The interactive nanomanipulation platform is established based on fuzzy control and connected region marking (CRM algorithm in SEM. The 3D virtual nanomanipulation model is developed to make up the insufficiency of the 2D SEM image information, which provides the operator with depth and real-time visual feedback information to guide the manipulation. The haptic device Omega3 is used as the master to control the 3D motion of the nanopositioner in master-slave mode and offer the force sensing to the operator controlled with fuzzy control algorithm. Aiming at sensing of force feedback during the nanomanipulation, the collision detection method of the virtual nanomanipulation model and the force rending model are studied to realize the force feedback of nanomanipulation. The CRM algorithm is introduced to process the SEM image which provides effective position data of the objects for updating the virtual environment (VE, and relevant issues such as calibration and update rate of VE are also discussed. Finally, the performance of the platform is validated by the ZnO nanowire manipulation experiments.

  19. SEM based overlay measurement between resist and buried patterns

    Science.gov (United States)

    Inoue, Osamu; Okagawa, Yutaka; Hasumi, Kazuhisa; Shao, Chuanyu; Leray, Philippe; Lorusso, Gian; Baudemprez, Bart

    2016-03-01

    With the continuous shrink in pattern size and increased density, overlay control has become one of the most critical issues in semiconductor manufacturing. Recently, SEM based overlay of AEI (After Etch Inspection) wafer has been used for reference and optimization of optical overlay (both Image Based Overlay (IBO) and Diffraction Based Overlay (DBO)). Overlay measurement at AEI stage contributes monitor and forecast the yield after formation by etch and calibrate optical measurement tools. however those overlay value seems difficult directly for feedback to a scanner. Therefore, there is a clear need to have SEM based overlay measurements of ADI (After Develop Inspection) wafers in order to serve as reference for optical overlay and make necessary corrections before wafers go to etch. Furthermore, to make the corrections as accurate as possible, actual device like feature dimensions need to be measured post ADI. This device size measurement is very unique feature of CDSEM , which can be measured with smaller area. This is currently possible only with the CD-SEM. This device size measurement is very unique feature of CD-SEM , which can be measured with smaller area. In this study, we assess SEM based overlay measurement of ADI and AEI wafer by using a sample from an N10 process flow. First, we demonstrate SEM based overlay performance at AEI by using dual damascene process for Via 0 (V0) and metal 1 (M1) layer. We also discuss the overlay measurements between litho-etch-litho stages of a triple patterned M1 layer and double pattern V0. Second, to illustrate the complexities in image acquisition and measurement we will measure overlay between M1B resist and buried M1A-Hard mask trench. Finally, we will show how high accelerating voltage can detect buried pattern information by BSE (Back Scattering Electron). In this paper we discuss the merits of this method versus standard optical metrology based corrections.

  20. Developing a TQM quality management method model

    NARCIS (Netherlands)

    Zhang, Zhihai

    1997-01-01

    From an extensive review of total quality management literature, the external and internal environment affecting an organization's quality performance and the eleven primary elements of TQM are identified. Based on the primary TQM elements, a TQM quality management method model is developed. This

  1. Deposition of ZnSO4 · 3Zn(OH2 · 4H2O films by SILAR method and their study by XRD, SEM and µ-Raman Depósito de películas de ZnSO4 • 3Zn(OH2 • 4H2O por el método SILAR y su estudio por DRX, SEM Y μ-RAMAN

    Directory of Open Access Journals (Sweden)

    F N Jiménez García

    2012-06-01

    Full Text Available ZnSO4 · 3Zn(OH2 · 4H2O(Zinc Sulfate Hidroxide Hidrate films were obtained on glass substrates by SILAR method. It was employed a precursorsolution of ZnSO4 and MnSO4 and water near boiling point complexed with 1 ml of NH4OH as a second solution. Films were treated on air at 300oC by 1 hour. Both films ZnSO4·3Zn(OH2·4H2O as ZnO are important protective against zinc corrosion because they are passive films that give a longer duration to material, it is therefore relevant to study their response to temperature changes. For those reasons films were analyzed before and after thermal treatment to study the structural and morphological changes by X ray diffraction (XRD, Scanning electron microscopy (SEM and Raman Microscopy techniques. It was found before thermal treatment by XRD thepresence of ZnSO4 · 3Zn(OH2 · 4H2O triclinic phase and after such treatment the ZnO hexagonal phase was evidenced. The morphology identified by SEM before thermal treatment was sheets formed by platelet like structure of micrometric size which changes after thermal treatment to a combination ofthose sheets with flowers like structure characteristic of ZnO hexagonal. By µ-Raman the hexagonal ZnO phase before thermal treatment as the triclinicZnSO4 · 3Zn(OH2 · 4H2O phase after thermal treatment were confirmed.One objective of this study was to obtain this protective corrosion material in a controlled manner by techiniques of low cost and high simplicity as Silarmethod. Which, even under temperture increases continue being protective corrosion although suffers phase changes because new phases have protectivecorrosive characteristics too.Se obtuvieron películas de ZnSO4 · 3Zn(OH2 · 4H2O (Zinc Sulfate Hidroxide Hidrate sobre sustratos de vidrio mediante procedimiento SILAR. Se empleó una solución precursora de ZnSO4 y MnSO4 y una segunda solución de agua a ebullición acomplejada con 1 ml de NH4OH. Se realizó tratamiento térmico en aire a 300oC por

  2. Acceleration methods and models in Sn calculations

    International Nuclear Information System (INIS)

    Sbaffoni, M.M.; Abbate, M.J.

    1984-01-01

    In some neutron transport problems solved by the discrete ordinate method, it is relatively common to observe some particularities as, for example, negative fluxes generation, slow and insecure convergences and solution instabilities. The commonly used models for neutron flux calculation and acceleration methods included in the most used codes were analyzed, in face of their use in problems characterized by a strong upscattering effect. Some special conclusions derived from this analysis are presented as well as a new method to perform the upscattering scaling for solving the before mentioned problems in this kind of cases. This method has been included in the DOT3.5 code (two dimensional discrete ordinates radiation transport code) generating a new version of wider application. (Author) [es

  3. Oxford CyberSEM: remote microscopy

    International Nuclear Information System (INIS)

    Rahman, M; Kirkland, A; Cockayne, D; Meyer, R

    2008-01-01

    The Internet has enabled researchers to communicate over vast geographical distances, sharing ideas and documents. e-Science, underpinned by Grid and Web Services, has enabled electronic communications to the next level where, in addition to document sharing, researchers can increasingly control high precision scientific instruments over the network. The Oxford CyberSEM project developed a simple Java applet via which samples placed in a JEOL 5510LV Scanning Electron Microscope (SEM) can be manipulated and examined collaboratively over the Internet. Designed with schoolchildren in mind, CyberSEM does not require any additional hardware or software other than a generic Java-enabled web browser. This paper reflects on both the technical and social challenges in designing real-time systems for controlling scientific equipments in collaborative environments. Furthermore, it proposes potential deployment beyond the classroom setting.

  4. Partial Least Squares Strukturgleichungsmodellierung (PLS-SEM)

    DEFF Research Database (Denmark)

    Hair, Joseph F.; Hult, G. Tomas M.; Ringle, Christian M.

    (PLS-SEM) hat sich in der wirtschafts- und sozialwissenschaftlichen Forschung als geeignetes Verfahren zur Schätzung von Kausalmodellen behauptet. Dank der Anwenderfreundlichkeit des Verfahrens und der vorhandenen Software ist es inzwischen auch in der Praxis etabliert. Dieses Buch liefert eine...... anwendungsorientierte Einführung in die PLS-SEM. Der Fokus liegt auf den Grundlagen des Verfahrens und deren praktischer Umsetzung mit Hilfe der SmartPLS-Software. Das Konzept des Buches setzt dabei auf einfache Erläuterungen statistischer Ansätze und die anschauliche Darstellung zahlreicher Anwendungsbeispiele anhand...... einer einheitlichen Fallstudie. Viele Grafiken, Tabellen und Illustrationen erleichtern das Verständnis der PLS-SEM. Zudem werden dem Leser herunterladbare Datensätze, Aufgaben und weitere Fachartikel zur Vertiefung angeboten. Damit eignet sich das Buch hervorragend für Studierende, Forscher und...

  5. Alternative methods of modeling wind generation using production costing models

    International Nuclear Information System (INIS)

    Milligan, M.R.; Pang, C.K.

    1996-08-01

    This paper examines the methods of incorporating wind generation in two production costing models: one is a load duration curve (LDC) based model and the other is a chronological-based model. These two models were used to evaluate the impacts of wind generation on two utility systems using actual collected wind data at two locations with high potential for wind generation. The results are sensitive to the selected wind data and the level of benefits of wind generation is sensitive to the load forecast. The total production cost over a year obtained by the chronological approach does not differ significantly from that of the LDC approach, though the chronological commitment of units is more realistic and more accurate. Chronological models provide the capability of answering important questions about wind resources which are difficult or impossible to address with LDC models

  6. Mathematical methods and models in composites

    CERN Document Server

    Mantic, Vladislav

    2014-01-01

    This book provides a representative selection of the most relevant, innovative, and useful mathematical methods and models applied to the analysis and characterization of composites and their behaviour on micro-, meso-, and macroscale. It establishes the fundamentals for meaningful and accurate theoretical and computer modelling of these materials in the future. Although the book is primarily concerned with fibre-reinforced composites, which have ever-increasing applications in fields such as aerospace, many of the results presented can be applied to other kinds of composites. The topics cover

  7. Intelligent structural optimization: Concept, Model and Methods

    International Nuclear Information System (INIS)

    Lu, Dagang; Wang, Guangyuan; Peng, Zhang

    2002-01-01

    Structural optimization has many characteristics of Soft Design, and so, it is necessary to apply the experience of human experts to solving the uncertain and multidisciplinary optimization problems in large-scale and complex engineering systems. With the development of artificial intelligence (AI) and computational intelligence (CI), the theory of structural optimization is now developing into the direction of intelligent optimization. In this paper, a concept of Intelligent Structural Optimization (ISO) is proposed. And then, a design process model of ISO is put forward in which each design sub-process model are discussed. Finally, the design methods of ISO are presented

  8. Electromagnetic modeling method for eddy current signal analysis

    International Nuclear Information System (INIS)

    Lee, D. H.; Jung, H. K.; Cheong, Y. M.; Lee, Y. S.; Huh, H.; Yang, D. J.

    2004-10-01

    An electromagnetic modeling method for eddy current signal analysis is necessary before an experiment is performed. Electromagnetic modeling methods consists of the analytical method and the numerical method. Also, the numerical methods can be divided by Finite Element Method(FEM), Boundary Element Method(BEM) and Volume Integral Method(VIM). Each modeling method has some merits and demerits. Therefore, the suitable modeling method can be chosen by considering the characteristics of each modeling. This report explains the principle and application of each modeling method and shows the comparison modeling programs

  9. Mathematical Models and Methods for Living Systems

    CERN Document Server

    Chaplain, Mark; Pugliese, Andrea

    2016-01-01

    The aim of these lecture notes is to give an introduction to several mathematical models and methods that can be used to describe the behaviour of living systems. This emerging field of application intrinsically requires the handling of phenomena occurring at different spatial scales and hence the use of multiscale methods. Modelling and simulating the mechanisms that cells use to move, self-organise and develop in tissues is not only fundamental to an understanding of embryonic development, but is also relevant in tissue engineering and in other environmental and industrial processes involving the growth and homeostasis of biological systems. Growth and organization processes are also important in many tissue degeneration and regeneration processes, such as tumour growth, tissue vascularization, heart and muscle functionality, and cardio-vascular diseases.

  10. Correlative SEM SERS for quantitative analysis of dimer nanoparticles.

    Science.gov (United States)

    Timmermans, F J; Lenferink, A T M; van Wolferen, H A G M; Otto, C

    2016-11-14

    A Raman microscope integrated with a scanning electron microscope was used to investigate plasmonic structures by correlative SEM-SERS analysis. The integrated Raman-SEM microscope combines high-resolution electron microscopy information with SERS signal enhancement from selected nanostructures with adsorbed Raman reporter molecules. Correlative analysis is performed for dimers of two gold nanospheres. Dimers were selected on the basis of SEM images from multi aggregate samples. The effect of the orientation of the dimer with respect to the polarization state of the laser light and the effect of the particle gap size on the Raman signal intensity is observed. Additionally, calculations are performed to simulate the electric near field enhancement. These simulations are based on the morphologies observed by electron microscopy. In this way the experiments are compared with the enhancement factor calculated with near field simulations and are subsequently used to quantify the SERS enhancement factor. Large differences between experimentally observed and calculated enhancement factors are regularly detected, a phenomenon caused by nanoscale differences between the real and 'simplified' simulated structures. Quantitative SERS experiments reveal the structure induced enhancement factor, ranging from ∼200 to ∼20 000, averaged over the full nanostructure surface. The results demonstrate correlative Raman-SEM microscopy for the quantitative analysis of plasmonic particles and structures, thus enabling a new analytical method in the field of SERS and plasmonics.

  11. New method dynamically models hydrocarbon fractionation

    Energy Technology Data Exchange (ETDEWEB)

    Kesler, M.G.; Weissbrod, J.M.; Sheth, B.V. [Kesler Engineering, East Brunswick, NJ (United States)

    1995-10-01

    A new method for calculating distillation column dynamics can be used to model time-dependent effects of independent disturbances for a range of hydrocarbon fractionation. It can model crude atmospheric and vacuum columns, with relatively few equilibrium stages and a large number of components, to C{sub 3} splitters, with few components and up to 300 equilibrium stages. Simulation results are useful for operations analysis, process-control applications and closed-loop control in petroleum, petrochemical and gas processing plants. The method is based on an implicit approach, where the time-dependent variations of inventory, temperatures, liquid and vapor flows and compositions are superimposed at each time step on the steady-state solution. Newton-Raphson (N-R) techniques are then used to simultaneously solve the resulting finite-difference equations of material, equilibrium and enthalpy balances that characterize distillation dynamics. The important innovation is component-aggregation and tray-aggregation to contract the equations without compromising accuracy. This contraction increases the N-R calculations` stability. It also significantly increases calculational speed, which is particularly important in dynamic simulations. This method provides a sound basis for closed-loop, supervisory control of distillation--directly or via multivariable controllers--based on a rigorous, phenomenological column model.

  12. Method of generating a computer readable model

    DEFF Research Database (Denmark)

    2008-01-01

    A method of generating a computer readable model of a geometrical object constructed from a plurality of interconnectable construction elements, wherein each construction element has a number of connection elements for connecting the construction element with another construction element. The met......A method of generating a computer readable model of a geometrical object constructed from a plurality of interconnectable construction elements, wherein each construction element has a number of connection elements for connecting the construction element with another construction element....... The method comprises encoding a first and a second one of the construction elements as corresponding data structures, each representing the connection elements of the corresponding construction element, and each of the connection elements having associated with it a predetermined connection type. The method...... further comprises determining a first connection element of the first construction element and a second connection element of the second construction element located in a predetermined proximity of each other; and retrieving connectivity information of the corresponding connection types of the first...

  13. Search Engine Marketing (SEM: Financial & Competitive Advantages of an Effective Hotel SEM Strategy

    Directory of Open Access Journals (Sweden)

    Leora Halpern Lanz

    2015-05-01

    Full Text Available Search Engine Marketing and Optimization (SEO, SEM are keystones of a hotels marketing strategy, in fact research shows that 90% of travelers start their vacation planning with a Google search. Learn five strategies that can enhance a hotels SEO and SEM strategies to boost bookings.

  14. Search Engine Marketing (SEM): Financial & Competitive Advantages of an Effective Hotel SEM Strategy

    OpenAIRE

    Leora Halpern Lanz

    2015-01-01

    Search Engine Marketing and Optimization (SEO, SEM) are keystones of a hotels marketing strategy, in fact research shows that 90% of travelers start their vacation planning with a Google search. Learn five strategies that can enhance a hotels SEO and SEM strategies to boost bookings.

  15. Does Sexually Explicit Media (SEM) Affect Me?

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Træen, Bente; Noor, Syed W

    2015-01-01

    and understanding of one’s sexual orientation.First-person effects refer to self-perceived and self-reported effects of SEM consumptionas experienced by the consumer. In addition, the study examined and provided athorough validation of the psychometric properties of the seven-item PornographyConsumption Effect...

  16. Building a SEM Analytics Reporting Portfolio

    Science.gov (United States)

    Goff, Jay W.; Williams, Brian G.; Kilgore, Wendy

    2016-01-01

    Effective strategic enrollment management (SEM) efforts require vast amounts of internal and external data to ensure that meaningful reporting and analysis systems can assist managers in decision making. A wide range of information is integral for leading effective and efficient student recruitment and retention programs. This article is designed…

  17. SEM and Raman studies of CNT films on porous Si

    Science.gov (United States)

    Belka, R.; Keczkowska, J.; Suchańska, M.; Firek, P.; Wronka, H.; Kozłowski, M.; Radomska, J.; Czerwosz, E.; Craciunoiu, F.

    2017-08-01

    Carbon nanotube (CNT) films deposited on different porous silica substrates were studied by Scanning Electron Microscopy (SEM) and Raman Spectroscopy (RS). The films samples were prepared by a two-step method consisting of PVD and CVD processes. In the first step the nanocomposite Ni-C film was obtained by evaporation in dynamic vacuum from two separated sources of fullerenes and nickel acetate. Those films were deposited on porous silica and DLC/porous silica substrates. Analysis of SEM imaging showed that the obtained film are composed of carbon nanotubes, the distribution, size and quality of which depend on the type of substrate. The CNT films were studied by RS method to determine the influence of the substrate type on disordering of carbonaceous structure and quality of CNT in deposited films.

  18. Application of SEM and EDX in studying biomineralization in plant tissues.

    Science.gov (United States)

    He, Honghua; Kirilak, Yaowanuj

    2014-01-01

    This chapter describes protocols using formalin-acetic acid-alcohol (FAA) to fix plant tissues for studying biomineralization by means of scanning electron microscopy (SEM) and qualitative energy-dispersive X-ray microanalysis (EDX). Specimen preparation protocols for SEM and EDX mainly include fixation, dehydration, critical point drying (CPD), mounting, and coating. Gold-coated specimens are used for SEM imaging, while gold- and carbon-coated specimens are prepared for qualitative X-ray microanalyses separately to obtain complementary information on the elemental compositions of biominerals. During the specimen preparation procedure for SEM, some biominerals may be dislodged or scattered, making it difficult to determine their accurate locations, and light microscopy is used to complement SEM studies. Specimen preparation protocols for light microscopy generally include fixation, dehydration, infiltration and embedding with resin, microtome sectioning, and staining. In addition, microwave processing methods are adopted here to speed up the specimen preparation process for both SEM and light microscopy.

  19. Engineering design of systems models and methods

    CERN Document Server

    Buede, Dennis M

    2009-01-01

    The ideal introduction to the engineering design of systems-now in a new edition. The Engineering Design of Systems, Second Edition compiles a wealth of information from diverse sources to provide a unique, one-stop reference to current methods for systems engineering. It takes a model-based approach to key systems engineering design activities and introduces methods and models used in the real world. Features new to this edition include: * The addition of Systems Modeling Language (SysML) to several of the chapters, as well as the introduction of new terminology * Additional material on partitioning functions and components * More descriptive material on usage scenarios based on literature from use case development * Updated homework assignments * The software product CORE (from Vitech Corporation) is used to generate the traditional SE figures and the software product MagicDraw UML with SysML plugins (from No Magic, Inc.) is used for the SysML figures This book is designed to be an introductory reference ...

  20. Railway Track Allocation: Models and Methods

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

    2011-01-01

    Efficiently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in finding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a conflict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

  1. Railway Track Allocation: Models and Methods

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

    Eciently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in nding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a con ict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

  2. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: MODELING

    Directory of Open Access Journals (Sweden)

    Brînduşa-Antonela SBÎRCEA

    2011-01-01

    Full Text Available By using active and participatory methods it is hoped that pupils will not only come to a deeper understanding of the issues involved, but also that their motivation will be heightened. Pupil involvement in their learning is essential. Moreover, by using a variety of teaching techniques, we can help students make sense of the world in different ways, increasing the likelihood that they will develop a conceptual understanding. The teacher must be a good facilitator, monitoring and supporting group dynamics. Modeling is an instructional strategy in which the teacher demonstrates a new concept or approach to learning and pupils learn by observing. In the teaching of biology the didactic materials are fundamental tools in the teaching-learning process. Reading about scientific concepts or having a teacher explain them is not enough. Research has shown that modeling can be used across disciplines and in all grade and ability level classrooms. Using this type of instruction, teachers encourage learning.

  3. Boundary element method for modelling creep behaviour

    International Nuclear Information System (INIS)

    Zarina Masood; Shah Nor Basri; Abdel Majid Hamouda; Prithvi Raj Arora

    2002-01-01

    A two dimensional initial strain direct boundary element method is proposed to numerically model the creep behaviour. The boundary of the body is discretized into quadratic element and the domain into quadratic quadrilaterals. The variables are also assumed to have a quadratic variation over the elements. The boundary integral equation is solved for each boundary node and assembled into a matrix. This matrix is solved by Gauss elimination with partial pivoting to obtain the variables on the boundary and in the interior. Due to the time-dependent nature of creep, the solution has to be derived over increments of time. Automatic time incrementation technique and backward Euler method for updating the variables are implemented to assure stability and accuracy of results. A flowchart of the solution strategy is also presented. (Author)

  4. Surface physics theoretical models and experimental methods

    CERN Document Server

    Mamonova, Marina V; Prudnikova, I A

    2016-01-01

    The demands of production, such as thin films in microelectronics, rely on consideration of factors influencing the interaction of dissimilar materials that make contact with their surfaces. Bond formation between surface layers of dissimilar condensed solids-termed adhesion-depends on the nature of the contacting bodies. Thus, it is necessary to determine the characteristics of adhesion interaction of different materials from both applied and fundamental perspectives of surface phenomena. Given the difficulty in obtaining reliable experimental values of the adhesion strength of coatings, the theoretical approach to determining adhesion characteristics becomes more important. Surface Physics: Theoretical Models and Experimental Methods presents straightforward and efficient approaches and methods developed by the authors that enable the calculation of surface and adhesion characteristics for a wide range of materials: metals, alloys, semiconductors, and complex compounds. The authors compare results from the ...

  5. Experimental modeling methods in Industrial Engineering

    Directory of Open Access Journals (Sweden)

    Peter Trebuňa

    2009-03-01

    Full Text Available Dynamic approaches to a management system of the present industrial practice, forcing businesses to address management issues in-house continuous improvement of production and non-production processes. Experience has repeatedly demonstrated the need for a system approach not only in analysis but also in the planning and actual implementation of these processes. Therefore, the contribution is focused on the description of the modeling in industrial practice by a system approach, in order to avoid erroneous application of the decision to the implementation phase, and thus prevent any longer applying methods "attempt - fallacy".

  6. Mechanics, Models and Methods in Civil Engineering

    CERN Document Server

    Maceri, Franco

    2012-01-01

    „Mechanics, Models and Methods in Civil Engineering” collects leading papers dealing with actual Civil Engineering problems. The approach is in the line of the Italian-French school and therefore deeply couples mechanics and mathematics creating new predictive theories, enhancing clarity in understanding, and improving effectiveness in applications. The authors of the contributions collected here belong to the Lagrange Laboratory, an European Research Network active since many years. This book will be of a major interest for the reader aware of modern Civil Engineering.

  7. The forward tracking, an optical model method

    CERN Document Server

    Benayoun, M

    2002-01-01

    This Note describes the so-called Forward Tracking, and the underlying optical model, developed in the context of LHCb-Light studies. Starting from Velo tracks, cheated or found by real pattern recognition, the tracks are found in the ST1-3 chambers after the magnet. The main ingredient to the method is a parameterisation of the track in the ST1-3 region, based on the Velo track parameters and an X seed in one ST station. Performance with the LHCb-Minus and LHCb-Light setups is given.

  8. Statistical Models and Methods for Lifetime Data

    CERN Document Server

    Lawless, Jerald F

    2011-01-01

    Praise for the First Edition"An indispensable addition to any serious collection on lifetime data analysis and . . . a valuable contribution to the statistical literature. Highly recommended . . ."-Choice"This is an important book, which will appeal to statisticians working on survival analysis problems."-Biometrics"A thorough, unified treatment of statistical models and methods used in the analysis of lifetime data . . . this is a highly competent and agreeable statistical textbook."-Statistics in MedicineThe statistical analysis of lifetime or response time data is a key tool in engineering,

  9. Bases de Datos Semánticas

    Directory of Open Access Journals (Sweden)

    Irving Caro Fierros

    2016-12-01

    Full Text Available En 1992, cuando Tim Berners-Lee dio a conocer la primera  versión  de  la  Web,  su  visión  a  futuro  era  incorporar metadatos  con  información  semántica  en  las  páginas  Web.  Es precisamente   a   principios   de   este   siglo   que   inicia   el   auge repentino  de  la  Web  semántica  en  el  ambiente  académico  e Internet. El modelo de datos semántico se define como un modelo conceptual que permite definir el significado de los datos a través de  sus  relaciones  con  otros.  En  este  sentido,  el  formato  de representación  de  los  datos  es  fundamental  para  proporcionar información de carácter semántico. La tecnología enfocada en las bases de datos semánticas se encuentra actualmente en un punto de  inflexión,  al  pasar  del  ámbito  académico  y  de  investigación  a ser una opción comercial completa. En este artículo se realiza un análisis  del  concepto  de  base  de  datos  semántica.  También  se presenta  un  caso  de  estudio  donde  se  ejemplifican  operaciones básicas  que  involucran  la  gestión  de  la  información  almacenada en este tipo de base de datos.

  10. QEM*SEM: a necessary tool in the metallurgical evaluation of ore bodies

    International Nuclear Information System (INIS)

    Creelman, R.A.; Gottlieb, P.; Sutherland, D.; Jackson, R.

    1989-01-01

    The QEM*SEM system for automated image analysis of mineral samples is described. Details of the equipment are given together with information on the methods of measurement. Finally some practical applications are described where QEM*SEM has been used for the solution of metallurgical problems. 14 refs., 1 fig

  11. A Bayesian statistical method for quantifying model form uncertainty and two model combination methods

    International Nuclear Information System (INIS)

    Park, Inseok; Grandhi, Ramana V.

    2014-01-01

    Apart from parametric uncertainty, model form uncertainty as well as prediction error may be involved in the analysis of engineering system. Model form uncertainty, inherently existing in selecting the best approximation from a model set cannot be ignored, especially when the predictions by competing models show significant differences. In this research, a methodology based on maximum likelihood estimation is presented to quantify model form uncertainty using the measured differences of experimental and model outcomes, and is compared with a fully Bayesian estimation to demonstrate its effectiveness. While a method called the adjustment factor approach is utilized to propagate model form uncertainty alone into the prediction of a system response, a method called model averaging is utilized to incorporate both model form uncertainty and prediction error into it. A numerical problem of concrete creep is used to demonstrate the processes for quantifying model form uncertainty and implementing the adjustment factor approach and model averaging. Finally, the presented methodology is applied to characterize the engineering benefits of a laser peening process

  12. Three dimensional rock microstructures: insights from FIB-SEM tomography

    Science.gov (United States)

    Drury, Martyn; Pennock, Gill; de Winter, Matthijs

    2016-04-01

    Most studies of rock microstructures investigate two-dimensional sections or thin slices of three dimensional grain structures. With advances of X-ray and electron tomography methods the 3-D microstructure can be(relatively) routinely investigated on scales from a few microns to cm. 3D studies are needed to investigate the connectivity of microstructures and to test the assumptions we use to calculate 3D properties from 2D sections. We have used FIB-SEM tomography to study the topology of melts in synthetic olivine rocks, 3D crystal growth microstructures, pore networks and subgrain structures. The technique uses a focused ion beam to make serial sections with a spacing of tens to hundreds of nanometers. Each section is then imaged or mapped using the electron beam. The 3D geometry of grains and subgrains can be investigated using orientation contrast or EBSD mapping. FIB-SEM tomography of rocks and minerals can be limited by charging of the uncoated surfaces exposed by the ion beam. The newest generation of FIB-SEMs have much improved low voltage imaging capability allowing high resolution charge free imaging. Low kV FIB-SEM tomography is now widely used to study the connectivity of pore networks. In-situ fluids can also be studied using cryo-FIB-SEM on frozen samples, although special freezing techniques are needed to avoid artifacts produced by ice crystallization. FIB-SEM tomography is complementary, in terms of spatial resolution and sampled volume, to TEM tomography and X-ray tomography, and the combination of these methods can cover a wide range of scales. Our studies on melt topology in synthetic olivine rocks with a high melt content show that many grain boundaries are wetted by nanometre scale melt layers that are too thin to resolve by X-ray tomography. A variety of melt layer geometries occur consistent with several mechanisms of melt layer formation. The nature of melt geometries along triple line junctions and quadruple points can be resolved

  13. SEM investigation of heart tissue samples

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, R; Amoroso, M [Physics Department, University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies (Trinidad and Tobago)

    2010-07-01

    We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm{sup 3} blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.

  14. SEM investigation of heart tissue samples

    International Nuclear Information System (INIS)

    Saunders, R; Amoroso, M

    2010-01-01

    We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm 3 blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.

  15. Viewing Integrated-Circuit Interconnections By SEM

    Science.gov (United States)

    Lawton, Russel A.; Gauldin, Robert E.; Ruiz, Ronald P.

    1990-01-01

    Back-scattering of energetic electrons reveals hidden metal layers. Experiment shows that with suitable operating adjustments, scanning electron microscopy (SEM) used to look for defects in aluminum interconnections in integrated circuits. Enables monitoring, in situ, of changes in defects caused by changes in temperature. Gives truer picture of defects, as etching can change stress field of metal-and-passivation pattern, causing changes in defects.

  16. Bases de Datos Semánticas

    OpenAIRE

    Irving Caro Fierros; Víctor Hugo Menéndez Domínguez; María Enriqueta Castellanos Bolaños

    2016-01-01

    En 1992, cuando Tim Berners-Lee dio a conocer la primera  versión  de  la  Web,  su  visión  a  futuro  era  incorporar metadatos  con  información  semántica  en  las  páginas  Web.  Es precisamente   a   principios   de   este   siglo   que   inicia   el   auge repentino  de  la  Web  semántica  en  el  ambiente  académico  e Internet. El modelo de datos semántico se define como un modelo conceptual que permite definir el significado de los datos a través de  sus  relaciones  con  otros.  E...

  17. Effect of defuzzification method of fuzzy modeling

    Science.gov (United States)

    Lapohos, Tibor; Buchal, Ralph O.

    1994-10-01

    Imprecision can arise in fuzzy relational modeling as a result of fuzzification, inference and defuzzification. These three sources of imprecision are difficult to separate. We have determined through numerical studies that an important source of imprecision is the defuzzification stage. This imprecision adversely affects the quality of the model output. The most widely used defuzzification algorithm is known by the name of `center of area' (COA) or `center of gravity' (COG). In this paper, we show that this algorithm not only maps the near limit values of the variables improperly but also introduces errors for middle domain values of the same variables. Furthermore, the behavior of this algorithm is a function of the shape of the reference sets. We compare the COA method to the weighted average of cluster centers (WACC) procedure in which the transformation is carried out based on the values of the cluster centers belonging to each of the reference membership functions instead of using the functions themselves. We show that this procedure is more effective and computationally much faster than the COA. The method is tested for a family of reference sets satisfying certain constraints, that is, for any support value the sum of reference membership function values equals one and the peak values of the two marginal membership functions project to the boundaries of the universe of discourse. For all the member sets of this family of reference sets the defuzzification errors do not get bigger as the linguistic variables tend to their extreme values. In addition, the more reference sets that are defined for a certain linguistic variable, the less the average defuzzification error becomes. In case of triangle shaped reference sets there is no defuzzification error at all. Finally, an alternative solution is provided that improves the performance of the COA method.

  18. Critical factors in SEM 3D stereo microscopy

    International Nuclear Information System (INIS)

    Marinello, F; Savio, E; Bariani, P; Horsewell, A; De Chiffre, L

    2008-01-01

    This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables and measurement parameters on reconstruction accuracy. Investigations were performed on a novel sample, specifically developed and implemented for the tests. The description is based on the model function introduced by Piazzesi and adapted for eucentrically tilted stereopairs. Two main classes of influencing factors are recognized: the first one is related to the measurement operation and the instrument set-up; the second concerns the quality of scanned images and represents the major criticality in the application of SEMs for 3D characterizations

  19. Three dimensional imaging of surface geometry in SEM

    International Nuclear Information System (INIS)

    Slowko, W.

    1997-01-01

    A great advantage of scanning electron microscopy (SEM) is its ability of the surface topography in the way as a human eye is accustomed to see lights and shadows on macroobjects. However, SEM's can hardly display vertical dimensions of the structures. One of possible solutions is reconstruction of the surface profiles by directional detection of secondary electrons and proper signal processing. However, the surface profile still gives two dimensional information and the method should be extended to obtain fully three dimensional imaging. The extension consists in a simultaneous reconstruction of the surface profiles in two perpendicular directions (x and y) and their superposition. The solution proposed is based on a quadrupole detector system and a computer or analogue system for signal processing. Quantitative data of the surface topography can be displayed in many manners in the system of two or three co-ordinates with use of pseudo-colour for the altitude coding. (author)

  20. Modeling error distributions of growth curve models through Bayesian methods.

    Science.gov (United States)

    Zhang, Zhiyong

    2016-06-01

    Growth curve models are widely used in social and behavioral sciences. However, typical growth curve models often assume that the errors are normally distributed although non-normal data may be even more common than normal data. In order to avoid possible statistical inference problems in blindly assuming normality, a general Bayesian framework is proposed to flexibly model normal and non-normal data through the explicit specification of the error distributions. A simulation study shows when the distribution of the error is correctly specified, one can avoid the loss in the efficiency of standard error estimates. A real example on the analysis of mathematical ability growth data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 is used to show the application of the proposed methods. Instructions and code on how to conduct growth curve analysis with both normal and non-normal error distributions using the the MCMC procedure of SAS are provided.

  1. Development of modelling method selection tool for health services management: from problem structuring methods to modelling and simulation methods.

    Science.gov (United States)

    Jun, Gyuchan T; Morris, Zoe; Eldabi, Tillal; Harper, Paul; Naseer, Aisha; Patel, Brijesh; Clarkson, John P

    2011-05-19

    There is an increasing recognition that modelling and simulation can assist in the process of designing health care policies, strategies and operations. However, the current use is limited and answers to questions such as what methods to use and when remain somewhat underdeveloped. The aim of this study is to provide a mechanism for decision makers in health services planning and management to compare a broad range of modelling and simulation methods so that they can better select and use them or better commission relevant modelling and simulation work. This paper proposes a modelling and simulation method comparison and selection tool developed from a comprehensive literature review, the research team's extensive expertise and inputs from potential users. Twenty-eight different methods were identified, characterised by their relevance to different application areas, project life cycle stages, types of output and levels of insight, and four input resources required (time, money, knowledge and data). The characterisation is presented in matrix forms to allow quick comparison and selection. This paper also highlights significant knowledge gaps in the existing literature when assessing the applicability of particular approaches to health services management, where modelling and simulation skills are scarce let alone money and time. A modelling and simulation method comparison and selection tool is developed to assist with the selection of methods appropriate to supporting specific decision making processes. In particular it addresses the issue of which method is most appropriate to which specific health services management problem, what the user might expect to be obtained from the method, and what is required to use the method. In summary, we believe the tool adds value to the scarce existing literature on methods comparison and selection.

  2. Comparison of SEM and VPSEM imaging techniques with respect to Streptococcus mutans biofilm topography.

    Science.gov (United States)

    Weber, Kathryn; Delben, Juliana; Bromage, Timothy G; Duarte, Simone

    2014-01-01

    The study compared images of mature Streptococcus mutans biofilms captured at increasing magnification to determine which microscopy method is most acceptable for imaging the biofilm topography and the extracellular polymeric substance (EPS). In vitro S. mutans biofilms were imaged using (1) scanning electron microscopy (SEM), which requires a dehydration process; (2) SEM and ruthenium red (SEM-RR), which has been shown to support the EPS of biofilms during the SEM dehydration; and (3) variable pressure scanning electron microscopy (VPSEM), which does not require the intensive dehydration process of SEM. The dehydration process and high chamber vacuum of both SEM techniques devastated the biofilm EPS, removed supporting structures, and caused cracking on the biofilm surface. The VPSEM offered the most comprehensive representation of the S. mutans biofilm morphology. VPSEM provides similar contrast and focus as the SEM, but the procedure is far less time-consuming, and the use of hazardous chemicals associated with SEM dehydration protocol is avoided with the VPSEM. The inaccurate representations of the biofilm EPS in SEM experimentation is a possible source of inaccurate data and impediments in the study of S. mutans biofilms. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  3. Does your SEM really tell the truth? How would you know? part 3: vibration and drift

    Science.gov (United States)

    Postek, Michael T.; Vladár, András. E.; Cizmar, Petr

    2014-09-01

    This is the third of a series of papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST. Scanned particle beam instruments especially the scanning electron microscope (SEM) have gone through tremendous evolution to become indispensable tools for many and diverse scientifi c and industrial applications. These improvements have signifi cantly enhanced their performance and made them far easier to operate. But, ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the need for extensive operator training. Unfortunately, this has led to the concept that the SEM is just another expensive digital camera or another peripheral device connected to a computer and that all of the issues related to obtaining quality data have been solved. Hence, a person (or company) using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and they believe everything they see on the micrograph is always correct. But, as described in this and the earlier presentations this may not be the case. The fi rst paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modelling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper, discussed another major issue confronting the microscopist: specimen contamination and methods of contamination elimination. This third paper, discusses vibration and drift and some useful solutions.

  4. Nanomanufacturing concerns about measurements made in the SEM Part III: vibration and drift

    Science.gov (United States)

    Postek, Michael T.; Vladár, András. E.; Cizmar, Petr

    2014-08-01

    Many advanced manufacturing processes employ scanning electron microscopes (SEM) for on-line critical measurements for process and quality control. This is the third of a series of papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST. Scanned particle beam instruments especially the scanning electron microscope have gone through tremendous evolution to become indispensable tools for many and diverse scientifi c and industrial applications. These improvements have signifi cantly enhanced their performance and made them far easier to operate. But, ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the need for extensive operator training. Unfortunately, this has led to the concept that the SEM is just another expensive digital camera or another peripheral device connected to a computer and that all of the issues related to obtaining quality data have been solved. Hence, a person (or company) using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and they believe everything they see on the micrograph is always correct. But, as described in this and the earlier presentations this may not be the case. The fi rst paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modelling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper, discussed another major issue confronting the microscopist: specimen contamination and methods of contamination elimination. This third paper, discusses vibration and drift and some useful solutions.

  5. Nanomanufacturing Concerns about Measurements Made in the SEM Part IV: Charging and its Mitigation.

    Science.gov (United States)

    Postek, Michael T; Vladár, András E

    2015-01-01

    This is the fourth part of a series of tutorial papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST and other research institutions. Scanned particle beam instruments especially the scanning electron microscope (SEM) have gone through tremendous evolution to become indispensable tools for many and diverse scientific and industrial applications. These improvements have significantly enhanced their performance and made them far easier to operate. But, the ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the apparent need for extensive operator training. Unfortunately, this has led to the idea that the SEM is just another expensive "digital camera" or another peripheral device connected to a computer and that all of the problems in obtaining good quality images and data have been solved. Hence, one using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and believing that, everything one sees on the micrograph is always correct. But, as described in this and the earlier papers, this may not be the case. Care must always be taken when reliable quantitative data are being sought. The first paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modeling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper has discussed another major issue confronting the microscopist: specimen contamination and methods to eliminate it. The third paper discussed mechanical vibration and stage drift and some useful solutions to mitigate the problems caused by them, and here, in this the fourth contribution, the issues related to specimen "charging" and its mitigation are discussed relative to

  6. Characterization of Yeast Biofilm by Cryo-SEM and FIB-SEM

    Czech Academy of Sciences Publication Activity Database

    Hrubanová, Kamila; Nebesářová, Jana; Růžička, F.; Dluhoš, J.; Krzyžánek, Vladislav

    2013-01-01

    Roč. 19, S2 (2013), s. 226-227 ISSN 1431-9276 R&D Projects: GA MŠk EE.2.3.20.0103; GA TA ČR TE01020118; GA ČR GAP205/11/1687 Institutional support: RVO:68081731 ; RVO:60077344 Keywords : yeast biofilm * cryo-SEM * FIB-SEM Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.757, year: 2013

  7. Two novel approaches to study arthropod anatomy by using dualbeam FIB/SEM.

    Science.gov (United States)

    Di Giulio, Andrea; Muzzi, Maurizio

    2018-03-01

    Transmission Electron Microscopy (TEM) has always been the conventional method to study arthropod ultrastructure, while the use of Scanning Electron Microscopy (SEM) was mainly devoted to the examination of the external cuticular structures by secondary electrons. The new generation field emission SEMs are capable to generate images at sub-cellular level, comparable to TEM images employing backscattered electrons. The potential of this kind of acquisition becomes very powerful in the dual beam FIB/SEM where the SEM column is combined with a Focused Ion Beam (FIB) column. FIB uses ions as a nano-scalpel to slice samples fixed and embedded in resin, replacing traditional ultramicrotomy. We here present two novel methods, which optimize the use of FIB/SEM for studying arthropod anatomy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Mathematical models and methods for planet Earth

    CERN Document Server

    Locatelli, Ugo; Ruggeri, Tommaso; Strickland, Elisabetta

    2014-01-01

    In 2013 several scientific activities have been devoted to mathematical researches for the study of planet Earth. The current volume presents a selection of the highly topical issues presented at the workshop “Mathematical Models and Methods for Planet Earth”, held in Roma (Italy), in May 2013. The fields of interest span from impacts of dangerous asteroids to the safeguard from space debris, from climatic changes to monitoring geological events, from the study of tumor growth to sociological problems. In all these fields the mathematical studies play a relevant role as a tool for the analysis of specific topics and as an ingredient of multidisciplinary problems. To investigate these problems we will see many different mathematical tools at work: just to mention some, stochastic processes, PDE, normal forms, chaos theory.

  9. Gait variability: methods, modeling and meaning

    Directory of Open Access Journals (Sweden)

    Hausdorff Jeffrey M

    2005-07-01

    Full Text Available Abstract The study of gait variability, the stride-to-stride fluctuations in walking, offers a complementary way of quantifying locomotion and its changes with aging and disease as well as a means of monitoring the effects of therapeutic interventions and rehabilitation. Previous work has suggested that measures of gait variability may be more closely related to falls, a serious consequence of many gait disorders, than are measures based on the mean values of other walking parameters. The Current JNER series presents nine reports on the results of recent investigations into gait variability. One novel method for collecting unconstrained, ambulatory data is reviewed, and a primer on analysis methods is presented along with a heuristic approach to summarizing variability measures. In addition, the first studies of gait variability in animal models of neurodegenerative disease are described, as is a mathematical model of human walking that characterizes certain complex (multifractal features of the motor control's pattern generator. Another investigation demonstrates that, whereas both healthy older controls and patients with a higher-level gait disorder walk more slowly in reduced lighting, only the latter's stride variability increases. Studies of the effects of dual tasks suggest that the regulation of the stride-to-stride fluctuations in stride width and stride time may be influenced by attention loading and may require cognitive input. Finally, a report of gait variability in over 500 subjects, probably the largest study of this kind, suggests how step width variability may relate to fall risk. Together, these studies provide new insights into the factors that regulate the stride-to-stride fluctuations in walking and pave the way for expanded research into the control of gait and the practical application of measures of gait variability in the clinical setting.

  10. FDTD method and models in optical education

    Science.gov (United States)

    Lin, Xiaogang; Wan, Nan; Weng, Lingdong; Zhu, Hao; Du, Jihe

    2017-08-01

    In this paper, finite-difference time-domain (FDTD) method has been proposed as a pedagogical way in optical education. Meanwhile, FDTD solutions, a simulation software based on the FDTD algorithm, has been presented as a new tool which helps abecedarians to build optical models and to analyze optical problems. The core of FDTD algorithm is that the time-dependent Maxwell's equations are discretized to the space and time partial derivatives, and then, to simulate the response of the interaction between the electronic pulse and the ideal conductor or semiconductor. Because the solving of electromagnetic field is in time domain, the memory usage is reduced and the simulation consequence on broadband can be obtained easily. Thus, promoting FDTD algorithm in optical education is available and efficient. FDTD enables us to design, analyze and test modern passive and nonlinear photonic components (such as bio-particles, nanoparticle and so on) for wave propagation, scattering, reflection, diffraction, polarization and nonlinear phenomena. The different FDTD models can help teachers and students solve almost all of the optical problems in optical education. Additionally, the GUI of FDTD solutions is so friendly to abecedarians that learners can master it quickly.

  11. The Effectiveness of Self-Expandable Metallic Stent Insertion in Treating Right-Sided Colonic Obstruction: A Comparison between SEMS and Decompression Tube Placement and an Investigation of the Safety and Difficulties of SEMS Insertion in Right Colons

    Directory of Open Access Journals (Sweden)

    Rintaro Moroi

    2014-01-01

    Full Text Available Objectives. Self-expandable metallic stent (SEMS is widely used to treat malignant colonic obstruction. However, most reports about SEMS insertion have concentrated on the left colon. This study aimed to (1 investigate the effectiveness of SEMS insertion compared with conventional decompression tube for right-sided colonic obstruction and (2 compare the safety and technical success of SEMS insertion between left- and right-sided colonic obstructions. Methods. The data from thirty-seven patients who underwent SEMS or conventional decompression tube placement for malignant colonic obstruction in our hospital were analyzed retrospectively. Technical and clinical success, complications, and technical difficulties were analyzed. We compared the results between SEMS insertion and decompression tube placement in right colons and the outcomes of SEMS insertion between right- and left-sided colonic obstructions. Results. For right colons, the clinical success rate of SEMS insertion (100% was significantly higher than that of decompression tube placement (55.9%. Concerning SEMS insertion, the technical difficulty and safety of SEMS insertion were similar between right- and left-sided colonic obstructions. Conclusion. SEMS insertion for right-sided colon is significantly more effective than conventional decompression tube placement, and this procedure was safer and less technically challenging than expected. SEMS insertion should be considered for treating right-sided malignant colonic obstruction.

  12. The relationship between cost estimates reliability and BIM adoption: SEM analysis

    Science.gov (United States)

    Ismail, N. A. A.; Idris, N. H.; Ramli, H.; Rooshdi, R. R. Raja Muhammad; Sahamir, S. R.

    2018-02-01

    This paper presents the usage of Structural Equation Modelling (SEM) approach in analysing the effects of Building Information Modelling (BIM) technology adoption in improving the reliability of cost estimates. Based on the questionnaire survey results, SEM analysis using SPSS-AMOS application examined the relationships between BIM-improved information and cost estimates reliability factors, leading to BIM technology adoption. Six hypotheses were established prior to SEM analysis employing two types of SEM models, namely the Confirmatory Factor Analysis (CFA) model and full structural model. The SEM models were then validated through the assessment on their uni-dimensionality, validity, reliability, and fitness index, in line with the hypotheses tested. The final SEM model fit measures are: P-value=0.000, RMSEA=0.0790.90, TLI=0.956>0.90, NFI=0.935>0.90 and ChiSq/df=2.259; indicating that the overall index values achieved the required level of model fitness. The model supports all the hypotheses evaluated, confirming that all relationship exists amongst the constructs are positive and significant. Ultimately, the analysis verified that most of the respondents foresee better understanding of project input information through BIM visualization, its reliable database and coordinated data, in developing more reliable cost estimates. They also perceive to accelerate their cost estimating task through BIM adoption.

  13. O ciberativismo sem bússola

    Directory of Open Access Journals (Sweden)

    Francisco Rüdiger

    2014-07-01

    Full Text Available Questiona-se no texto se uma abordagem que, no essencial, relata a trajetória do chamado ciberativismo de acordo com seus próprios termos se justifica academicamente ou, em vez disso, se mantém prisioneira de uma mitologia que o fenômeno, em si mesmo, já construiu e, por isso, autoriza seus sujeitos a dispensarem sem prejuízo eventual contribuição de origem universitária.

  14. Afasia global sem hemiparesia: relato de caso

    OpenAIRE

    SILVA,MARCUS TULIUS TEIXEIRA DA; CAVALCANTI,JOSÉ LUÍS DE SÁ; MOREIRA,DENISE MADEIRA

    2000-01-01

    Afasia global geralmente é acompanhada por hemiparesia direita devido à extensão da lesão subjacente. Recentemente têm sido registrados na literatura casos em que tal síndrome ou não se acompanha do déficit motor ou este é apenas transitório, sendo esta condição conhecida como afasia global sem hemiparesia (AGSH). Relatamos caso de AGSH devido a infarto cerebral embólico cardiogênico, corroborando a tese de que esta condição pode ter valor preditivo para o diagnóstico de infartos embólicos....

  15. Free wake models for vortex methods

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, K. [Technical Univ. Berlin, Aerospace Inst. (Germany)

    1997-08-01

    The blade element method works fast and good. For some problems (rotor shapes or flow conditions) it could be better to use vortex methods. Different methods for calculating a wake geometry will be presented. (au)

  16. Analysis of microtraces in invasive traumas using SEM/EDS.

    Science.gov (United States)

    Vermeij, E J; Zoon, P D; Chang, S B C G; Keereweer, I; Pieterman, R; Gerretsen, R R R

    2012-01-10

    Scanning electron microscopy in combination with energy-dispersive X-ray spectrometry (SEM/EDS) is a proven forensic tool and has been used to analyze several kinds of trace evidence. A forensic application of SEM/EDS is the examination of morphological characteristics of tool marks that tools and instruments leave on bone. The microtraces that are left behind by these tools and instruments on the bone are, however, often ignored or not noticed at all. In this paper we will describe the use of SEM/EDS for the analysis of microtraces in invasive sharp-force, blunt-force and bone-hacking traumas in bone. This research is part of a larger multi-disciplinary approach in which pathologists, forensic anthropologists, toolmark and microtrace experts work together to link observed injuries to a suspected weapon or, in case of an unknown weapon, to indicate a group of objects that could have been used as a weapon. Although there are a few difficulties one have to consider, the method itself is rather simple and straightforward to apply. A sample of dry and clean bone is placed into the SEM sample chamber and brightness and contrast are set such that bone appears grey, metal appears white and organic material appears black. The sample is then searched manually to find relevant features. Once features are found their elemental composition is measured by an energy dispersive X-ray spectrometer (EDS). This method is illustrated using several cases. It is shown that SEM/EDS analysis of microtraces in bone is a valuable tool to get clues about an unknown weapon and can associate a specific weapon with injuries on the basis of appearance and elemental composition. In particular the separate results from the various disciplines are complementary and may be combined to reach a conclusion with a stronger probative value. This is not only useful in the courtroom but above all in criminal investigations when one have to know for what weapon or object to look for. Copyright © 2011

  17. The SEM description of interaction of a transient electromagnetic wave with an object

    Science.gov (United States)

    Pearson, L. W.; Wilton, D. R.

    1980-01-01

    The singularity expansion method (SEM), proposed as a means for determining and representing the transient surface current density induced on a scatterer by a transient electromagnetic wave is described. The resulting mathematical description of the transient surface current on the object is discussed. The data required to represent the electromagnetic scattering properties of a given object are examined. Experimental methods which were developed for the determination of the SEM description are discussed. The feasibility of characterizing the surface current induced on aircraft flying in proximity to a lightning stroke by way of SEM is examined.

  18. Quantitative roughness characterization and 3D reconstruction of electrode surface using cyclic voltammetry and SEM image

    Energy Technology Data Exchange (ETDEWEB)

    Dhillon, Shweta; Kant, Rama, E-mail: rkant@chemistry.du.ac.in

    2013-10-01

    Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.

  19. Quantitative roughness characterization and 3D reconstruction of electrode surface using cyclic voltammetry and SEM image

    International Nuclear Information System (INIS)

    Dhillon, Shweta; Kant, Rama

    2013-01-01

    Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.

  20. A business case method for business models

    NARCIS (Netherlands)

    Meertens, Lucas Onno; Starreveld, E.; Iacob, Maria Eugenia; Nieuwenhuis, Lambertus Johannes Maria; Shishkov, Boris

    2013-01-01

    Intuitively, business cases and business models are closely connected. However, a thorough literature review revealed no research on the combination of them. Besides that, little is written on the evaluation of business models at all. This makes it difficult to compare different business model

  1. El semáforo loco

    OpenAIRE

    González de Zachrisson, Hena

    2016-01-01

    El semáforo lo acababan de instalar en Vía Brasil y Calle 50 y estaba contento de poder mantener el orden del tránsito en tan importante calle. Sin embargo, pronto descubrió que su tarea no era fácil. Su territorio estaba atestado de muchachos que vendían frutas y vegetales y para escapar de ellos, los conductores hacían regatas para cruzar la calle antes de que la luz cambiara a rojo. —Todo a un dólar! —gritaban los chicos mostrando su bolsa de guineo, naranja, melón, maíz, papaya, c...

  2. In-situ SEM electrochemistry and radiolysis

    DEFF Research Database (Denmark)

    Møller-Nilsen, Rolf Erling Robberstad; Norby, Poul

    are backscattered and an image is reconstructed by the microscope. But the high energy electrons are a form of ionising radiation which can significantly affect the chemistry in liquid experiments. Ionising radiation can split water, produce radicals, reduce dissolved metal ions to metal particles, and more...... experiments. During the course of these studies it has also been possible to improve on the EC-SEM system. This has resulted in pyrolysed carbon electrodes, which offer the benefit of stability at 0.75 V higher potentials than traditional gold thin-film electrodes. With the quantitative insight...... microelectrodes on the windows to enable studies of electrohcemical processes. In this way it is possible to perform in-situ electrochemical experiments such as electroplating and charge and discharge analysis of battery electrodes. In a typical liquid cell, electrons are accelerated to sufficiently high energies...

  3. Cultivo de células mesenquimais do sangue de cordão umbilical com e sem uso do gradiente de densidade Ficoll-Paque Blood mesenchymal stem cell culture from the umbilical cord with and without Ficoll-Paque density gradient method

    Directory of Open Access Journals (Sweden)

    Rosa Sayoko Kawasaki-Oyama

    2008-03-01

    Full Text Available OBJETIVOS: Implantação de técnicas de isolamento e cultivo de células-tronco mesenquimais do sangue de cordão umbilical humano, com e sem uso de gradiente de densidade Ficoll-Paque (d=1,077g/ml. MÉTODOS: Dez amostras de sangue de cordão umbilical humano de gestação a termo foram submetidas a dois procedimentos de cultivo de células-tronco mesenquimais: sem gradiente de densidade Ficoll-Paque e com gradiente de densidade. As células foram semeadas em frascos de 25cm² a uma densidade de 1x10(7células nucleadas/cm² (sem Ficoll e 1,0x10(6 células mononucleares/cm² (com Ficoll. As células aderentes foram submetidas a marcação citoquímica com fosfatase ácida e reativo de Schiff. RESULTADOS: No procedimento sem gradiente de densidade Ficoll, foram obtidas 2,0-13,0x10(7 células nucleadas (mediana=2,35x10(7 e, no procedimento com gradiente de densidade Ficoll, foram obtidas 3,7-15,7x10(6 células mononucleares (mediana=7,2x10(6. Em todas as culturas foram observadas células aderentes 24 horas após o início de cultivo. As células apresentaram morfologias fibroblastóides ou epitelióides. Na maioria das culturas houve proliferação celular nas primeiras semanas de cultivo, mas após a segunda semana, somente três culturas provenientes do método sem gradiente de densidade Ficoll-Paque mantiveram crescimento celular, formando focos confluentes de células. Essas culturas foram submetidas a várias etapas de tripsinização para espalhamento ou subdivisão e permaneceram em cultivo por períodos que variaram de dois a três meses. CONCLUSÃO: Nas amostras estudadas, o isolamento e cultivo de células-tronco mesenquimais do sangue de cordão umbilical humano pelo método sem gradiente de densidade Ficoll-Paque foi mais eficiente do que o método com gradiente de densidade Ficoll-Paque.OBJECTIVES: Implantation of cell separation and mesenchymal stem cell culture techniques from human umbilical cord blood with and without using the

  4. How Qualitative Methods Can be Used to Inform Model Development.

    Science.gov (United States)

    Husbands, Samantha; Jowett, Susan; Barton, Pelham; Coast, Joanna

    2017-06-01

    Decision-analytic models play a key role in informing healthcare resource allocation decisions. However, there are ongoing concerns with the credibility of models. Modelling methods guidance can encourage good practice within model development, but its value is dependent on its ability to address the areas that modellers find most challenging. Further, it is important that modelling methods and related guidance are continually updated in light of any new approaches that could potentially enhance model credibility. The objective of this article was to highlight the ways in which qualitative methods have been used and recommended to inform decision-analytic model development and enhance modelling practices. With reference to the literature, the article discusses two key ways in which qualitative methods can be, and have been, applied. The first approach involves using qualitative methods to understand and inform general and future processes of model development, and the second, using qualitative techniques to directly inform the development of individual models. The literature suggests that qualitative methods can improve the validity and credibility of modelling processes by providing a means to understand existing modelling approaches that identifies where problems are occurring and further guidance is needed. It can also be applied within model development to facilitate the input of experts to structural development. We recommend that current and future model development would benefit from the greater integration of qualitative methods, specifically by studying 'real' modelling processes, and by developing recommendations around how qualitative methods can be adopted within everyday modelling practice.

  5. Three-Dimensional (3D) Nanometrology Based on Scanning Electron Microscope (SEM) Stereophotogrammetry.

    Science.gov (United States)

    Tondare, Vipin N; Villarrubia, John S; Vlada R, András E

    2017-10-01

    Three-dimensional (3D) reconstruction of a sample surface from scanning electron microscope (SEM) images taken at two perspectives has been known for decades. Nowadays, there exist several commercially available stereophotogrammetry software packages. For testing these software packages, in this study we used Monte Carlo simulated SEM images of virtual samples. A virtual sample is a model in a computer, and its true dimensions are known exactly, which is impossible for real SEM samples due to measurement uncertainty. The simulated SEM images can be used for algorithm testing, development, and validation. We tested two stereophotogrammetry software packages and compared their reconstructed 3D models with the known geometry of the virtual samples used to create the simulated SEM images. Both packages performed relatively well with simulated SEM images of a sample with a rough surface. However, in a sample containing nearly uniform and therefore low-contrast zones, the height reconstruction error was ≈46%. The present stereophotogrammetry software packages need further improvement before they can be used reliably with SEM images with uniform zones.

  6. Three-dimensional intracellular structure of a whole rice mesophyll cell observed with FIB-SEM.

    Science.gov (United States)

    Oi, Takao; Enomoto, Sakiko; Nakao, Tomoyo; Arai, Shigeo; Yamane, Koji; Taniguchi, Mitsutaka

    2017-07-01

    Ultrathin sections of rice leaf blades observed two-dimensionally using a transmission electron microscope (TEM) show that the chlorenchyma is composed of lobed mesophyll cells, with intricate cell boundaries, and lined with chloroplasts. The lobed cell shape and chloroplast positioning are believed to enhance the area available for the gas exchange surface for photosynthesis in rice leaves. However, a cell image revealing the three-dimensional (3-D) ultrastructure of rice mesophyll cells has not been visualized. In this study, a whole rice mesophyll cell was observed using a focused ion beam scanning electron microscope (FIB-SEM), which provides many serial sections automatically, rapidly and correctly, thereby enabling 3-D cell structure reconstruction. Rice leaf blades were fixed chemically using the method for conventional TEM observation, embedded in resin and subsequently set in the FIB-SEM chamber. Specimen blocks were sectioned transversely using the FIB, and block-face images were captured using the SEM. The sectioning and imaging were repeated overnight for 200-500 slices (each 50 nm thick). The resultant large-volume image stacks ( x = 25 μm, y = 25 μm, z = 10-25 μm) contained one or two whole mesophyll cells. The 3-D models of whole mesophyll cells were reconstructed using image processing software. The reconstructed cell models were discoid shaped with several lobes around the cell periphery. The cell shape increased the surface area, and the ratio of surface area to volume was twice that of a cylinder having the same volume. The chloroplasts occupied half the cell volume and spread as sheets along the cell lobes, covering most of the inner cell surface, with adjacent chloroplasts in close contact with each other. Cellular and sub-cellular ultrastructures of a whole mesophyll cell in a rice leaf blade are demonstrated three-dimensionally using a FIB-SEM. The 3-D models and numerical information support the hypothesis that rice mesophyll

  7. Enhancing nanoscale SEM image segmentation and reconstruction with crystallographic orientation data and machine learning

    International Nuclear Information System (INIS)

    Converse, Matthew I.; Fullwood, David T.

    2013-01-01

    Current methods of image segmentation and reconstructions from scanning electron micrographs can be inadequate for resolving nanoscale gaps in composite materials (1–20 nm). Such information is critical to both accurate material characterizations and models of piezoresistive response. The current work proposes the use of crystallographic orientation data and machine learning for enhancing this process. It is first shown how a machine learning algorithm can be used to predict the connectivity of nanoscale grains in a Nickel nanostrand/epoxy composite. This results in 71.9% accuracy for a 2D algorithm and 62.4% accuracy in 3D. Finally, it is demonstrated how these algorithms can be used to predict the location of gaps between distinct nanostrands — gaps which would otherwise not be detected with the sole use of a scanning electron microscope. - Highlights: • A method is proposed for enhancing the segmentation/reconstruction of SEM images. • 3D crystallographic orientation data from a nickel nanocomposite is collected. • A machine learning algorithm is used to detect trends in adjacent grains. • This algorithm is then applied to predict likely regions of nanoscale gaps. • These gaps would otherwise be unresolved with the sole use of an SEM

  8. A combined technique using SEM and TOPSIS for the commercialization capability of R&D project evaluation

    Directory of Open Access Journals (Sweden)

    Charttirot Karaveg

    2015-07-01

    Full Text Available There is a high risk of R&D based innovation being commercialized, especially in the innovation transfer process which is a concern to many entrepreneurs and researchers. The purpose of this research is to develop the criteria of R&D commercialization capability and to propose a combined technique of Structural Equation Modelling (SEM and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS for R&D project evaluation. The research utilized a mixed-method approach. The first phase comprised a qualitative study on commercialization criteria development though the survey research of 272 successful entrepreneurs and researchers in all industrial sectors in Thailand. The data was collected with a structured questionnaire and analyzed by SEM. The second phase was involved with SEM-TOPSIS technique development and a case study of 45 R&D projects in research institutes and incubators for technique validation. The research results reveal that there were six criteria for R&D project commercialization capability, these are arranged according to the significance; marketing, technology, finance, non-financial impact, intellectual property, and human resource. The holistic criteria is presented in decreasing order on the ambiguous subjectivity of the fuzzy-expert system, to help with effectively funding R&D and to prevent a resource meltdown. This study applies SEM to the relative weighting of hierarchical criteria. The TOPSIS approach is employed to rank the alternative performance. An integrated SEM-TOPSIS is proposed for the first time and applied to present R&D projects shown to be effective and feasible in evaluating R&D commercialization capacity.

  9. The luminal surface of thyroid cysts in SEM

    DEFF Research Database (Denmark)

    Zelander, T; Kirkeby, S

    1978-01-01

    Four of the five kinds of cells constituting the walls of thyroid cysts can be identified in the SEM. These are cuboidal cells, mucous cells, cells with large granules and ciliated cells. A correlation between SEM and TEM observations is attempted.......Four of the five kinds of cells constituting the walls of thyroid cysts can be identified in the SEM. These are cuboidal cells, mucous cells, cells with large granules and ciliated cells. A correlation between SEM and TEM observations is attempted....

  10. Dynamic spatial panels : models, methods, and inferences

    NARCIS (Netherlands)

    Elhorst, J. Paul

    This paper provides a survey of the existing literature on the specification and estimation of dynamic spatial panel data models, a collection of models for spatial panels extended to include one or more of the following variables and/or error terms: a dependent variable lagged in time, a dependent

  11. Methods of Medical Guidelines Modelling in GLIF.

    Czech Academy of Sciences Publication Activity Database

    Buchtela, David; Anger, Z.; Peleška, Jan (ed.); Tomečková, Marie; Veselý, Arnošt; Zvárová, Jana

    2005-01-01

    Roč. 11, - (2005), s. 1529-1532 ISSN 1727-1983. [EMBEC'05. European Medical and Biomedical Conference /3./. Prague, 20.11.2005-25.11.2005] Institutional research plan: CEZ:AV0Z10300504 Keywords : medical guidelines * knowledge modelling * GLIF model Subject RIV: BD - Theory of Information

  12. Sem-edx and ftir studies of chlorinated rubber coating

    International Nuclear Information System (INIS)

    Bano, H.; Khan, M.I.

    2013-01-01

    Summary: Anticorrosive performance of chlorinated rubber coating has been investigated by visual examination, Scanning electron microscopy (SEM)/Energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. After surface preparation, commercially available coating system based on chlorinated rubber (primer)/chlorinated rubber (topcoat) formulation was applied on mild steel test panels (10cm x 15cm sizes). Prepared coated panels were exposed at marine, industrial and urban test sites located in Karachi, Pakistan according to ISO 8565 norm. Accelerated testing was performed by using a salt spray chamber (ASTM B117 norm). Accelerated weathering methods are the methods in which the factors responsible for the degradation of coatings are artificially intensified in order to achieve the rapid degradation of coatings. Visual examination of blistering and rusting as well as SEM micrographs indicated a more severe degradation of the coating surface characteristics at natural exposure testing sites (particularly at marine test site) than for accelerated (salt spray) testing. EDX determination of the Oxygen/Carbon (O/C) ratios also indicated increased degradation at natural test sites compared to the accelerated (salt spray) testing. Photooxidation of the binder results in the formation of carbonyl compounds as revealed by FTIR spectroscopy which also indicated dehydrochlorination. (author)

  13. Classification and printability of EUV mask defects from SEM images

    Science.gov (United States)

    Cho, Wonil; Price, Daniel; Morgan, Paul A.; Rost, Daniel; Satake, Masaki; Tolani, Vikram L.

    2017-10-01

    -to-Aerial printability) analysis of every defect. First, a defect-free or reference mask SEM is rendered from the post-OPC design, and the defective signature is detected from the defect-reference difference image. These signatures help assess the true nature of the defect as evident in e-beam imaging; for example, excess or missing absorber, line-edge roughness, contamination, etc. Next, defect and reference contours are extracted from the grayscale SEM images and fed into the simulation engine with an EUV scanner model to generate corresponding EUV defect and reference aerial images. These are then analyzed for printability and dispositioned using an Aerial Image Analyzer (AIA) application to automatically measure and determine the amount of CD errors. Thus by integrating EUV ADC and S2A applications together, every defect detection is characterized for its type and printability which is essential for not only determining which defects to repair, but also in monitoring the performance of EUV mask process tools. The accuracy of the S2A print modeling has been verified with other commercially-available simulators, and will also be verified with actual wafer print results. With EUV lithography progressing towards volume manufacturing at 5nm technology, and the likelihood of EBMI inspectors approaching the horizon, the EUV ADC-S2A system will continue serving an essential role of dispositioning defects off e-beam imaging.

  14. Assessment of engineered surfaces roughness by high-resolution 3D SEM photogrammetry.

    Science.gov (United States)

    Gontard, L C; López-Castro, J D; González-Rovira, L; Vázquez-Martínez, J M; Varela-Feria, F M; Marcos, M; Calvino, J J

    2017-06-01

    We describe a methodology to obtain three-dimensional models of engineered surfaces using scanning electron microscopy and multi-view photogrammetry (3DSEM). For the reconstruction of the 3D models of the surfaces we used freeware available in the cloud. The method was applied to study the surface roughness of metallic samples patterned with parallel grooves by means of laser. The results are compared with measurements obtained using stylus profilometry (PR) and SEM stereo-photogrammetry (SP). The application of 3DSEM is more time demanding than PR or SP, but it provides a more accurate representation of the surfaces. The results obtained with the three techniques are compared by investigating the influence of sampling step on roughness parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Fluid Methods for Modeling Large, Heterogeneous Networks

    National Research Council Canada - National Science Library

    Towsley, Don; Gong, Weibo; Hollot, Kris; Liu, Yong; Misra, Vishal

    2005-01-01

    .... The resulting fluid models were used to develop novel active queue management mechanisms resulting in more stable TCP performance and novel rate controllers for the purpose of providing minimum rate...

  16. Combining static and dynamic modelling methods: a comparison of four methods

    NARCIS (Netherlands)

    Wieringa, Roelf J.

    1995-01-01

    A conceptual model of a system is an explicit description of the behaviour required of the system. Methods for conceptual modelling include entity-relationship (ER) modelling, data flow modelling, Jackson System Development (JSD) and several object-oriented analysis method. Given the current

  17. A Pattern-Oriented Approach to a Methodical Evaluation of Modeling Methods

    Directory of Open Access Journals (Sweden)

    Michael Amberg

    1996-11-01

    Full Text Available The paper describes a pattern-oriented approach to evaluate modeling methods and to compare various methods with each other from a methodical viewpoint. A specific set of principles (the patterns is defined by investigating the notations and the documentation of comparable modeling methods. Each principle helps to examine some parts of the methods from a specific point of view. All principles together lead to an overall picture of the method under examination. First the core ("method neutral" meaning of each principle is described. Then the methods are examined regarding the principle. Afterwards the method specific interpretations are compared with each other and with the core meaning of the principle. By this procedure, the strengths and weaknesses of modeling methods regarding methodical aspects are identified. The principles are described uniformly using a principle description template according to descriptions of object oriented design patterns. The approach is demonstrated by evaluating a business process modeling method.

  18. Characterisation of nanoparticles by means of high-resolution SEM/EDS in transmission mode

    International Nuclear Information System (INIS)

    Hodoroaba, V-D; Rades, S; Mielke, J; Ortel, E; Salge, T; Schmidt, R

    2016-01-01

    Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass - thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS. (paper)

  19. Inter-operator and inter-device agreement and reliability of the SEM Scanner.

    Science.gov (United States)

    Clendenin, Marta; Jaradeh, Kindah; Shamirian, Anasheh; Rhodes, Shannon L

    2015-02-01

    The SEM Scanner is a medical device designed for use by healthcare providers as part of pressure ulcer prevention programs. The objective of this study was to evaluate the inter-rater and inter-device agreement and reliability of the SEM Scanner. Thirty-one (31) volunteers free of pressure ulcers or broken skin at the sternum, sacrum, and heels were assessed with the SEM Scanner. Each of three operators utilized each of three devices to collect readings from four anatomical sites (sternum, sacrum, left and right heels) on each subject for a total of 108 readings per subject collected over approximately 30 min. For each combination of operator-device-anatomical site, three SEM readings were collected. Inter-operator and inter-device agreement and reliability were estimated. Over the course of this study, more than 3000 SEM Scanner readings were collected. Agreement between operators was good with mean differences ranging from -0.01 to 0.11. Inter-operator and inter-device reliability exceeded 0.80 at all anatomical sites assessed. The results of this study demonstrate the high reliability and good agreement of the SEM Scanner across different operators and different devices. Given the limitations of current methods to prevent and detect pressure ulcers, the SEM Scanner shows promise as an objective, reliable tool for assessing the presence or absence of pressure-induced tissue damage such as pressure ulcers. Copyright © 2015 Bruin Biometrics, LLC. Published by Elsevier Ltd.. All rights reserved.

  20. Analysis list: sem-4 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available sem-4 Larvae + ce10 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.1....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem...-4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/sem-4.Larvae.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/Larvae.gml ...

  1. Stirling Energy Module (SEM) as Micro-CHP; Stirling Energy Module (SEM) als Mini-BHKW

    Energy Technology Data Exchange (ETDEWEB)

    Schlegel, A.

    2006-07-01

    Since many years, a lot of effort is being put into the development of combined heat and power units (CHP) for the decentralised production of electric power. For long time, the main focus was on fuel cells. In the meantime, the Stirling technology, which is based upon classical mechanical engineering and innovative technical concepts, proceeded in its development as well. The following article describes the technology and the actual state of the development of the Stirling Energy Module (SEM) for the application as Micro-CHP in one-family-houses. SEM is based on a free-piston engine with a linear power generator, producing electric power while heating. The Stirling engine is planned the be introduced into the market as a replacement for the conventional heating systems within a couple of years. (author)

  2. Accurate Electromagnetic Modeling Methods for Integrated Circuits

    NARCIS (Netherlands)

    Sheng, Z.

    2010-01-01

    The present development of modern integrated circuits (IC’s) is characterized by a number of critical factors that make their design and verification considerably more difficult than before. This dissertation addresses the important questions of modeling all electromagnetic behavior of features on

  3. Reduced Order Modeling Methods for Turbomachinery Design

    Science.gov (United States)

    2009-03-01

    and Ma- terials Conference, May 2006. [45] A. Gelman , J. B. Carlin, H. S. Stern, and D. B. Rubin, Bayesian Data Analysis. New York, NY: Chapman I& Hall...Macian- Juan , and R. Chawla, “A statistical methodology for quantif ca- tion of uncertainty in best estimate code physical models,” Annals of Nuclear En

  4. Introduction to mathematical models and methods

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqi, A. H.; Manchanda, P. [Gautam Budha University, Gautam Budh Nagar-201310 (India); Department of Mathematics, Guru Nanak Dev University, Amritsar (India)

    2012-07-17

    Some well known mathematical models in the form of partial differential equations representing real world systems are introduced along with fundamental concepts of Image Processing. Notions such as seismic texture, seismic attributes, core data, well logging, seismic tomography and reservoirs simulation are discussed.

  5. A catalog of automated analysis methods for enterprise models.

    Science.gov (United States)

    Florez, Hector; Sánchez, Mario; Villalobos, Jorge

    2016-01-01

    Enterprise models are created for documenting and communicating the structure and state of Business and Information Technologies elements of an enterprise. After models are completed, they are mainly used to support analysis. Model analysis is an activity typically based on human skills and due to the size and complexity of the models, this process can be complicated and omissions or miscalculations are very likely. This situation has fostered the research of automated analysis methods, for supporting analysts in enterprise analysis processes. By reviewing the literature, we found several analysis methods; nevertheless, they are based on specific situations and different metamodels; then, some analysis methods might not be applicable to all enterprise models. This paper presents the work of compilation (literature review), classification, structuring, and characterization of automated analysis methods for enterprise models, expressing them in a standardized modeling language. In addition, we have implemented the analysis methods in our modeling tool.

  6. Comparative SEM analysis of nine F22 aligner cleaning strategies.

    Science.gov (United States)

    Lombardo, Luca; Martini, Marco; Cervinara, Francesca; Spedicato, Giorgio Alfredo; Oliverio, Teresa; Siciliani, Giuseppe

    2017-12-01

    The orthodontics industry has paid great attention to the aesthetics of orthodontic appliances, seeking to make them as invisible as possible. There are several advantages to clear aligner systems, including aesthetics, comfort, chairside time reduction, and the fact that they can be removed for meals and oral hygiene procedures. Five patients were each given a series of F22 aligners, each to be worn for 14 days and nights, with the exception of meal and brushing times. Patients were instructed to clean each aligner using a prescribed strategy, and sections of the used aligners were observed under SEM. One grey-scale SEM image was saved per aligner in JPEG format with an 8-bit colour depth, and a total of 45 measurements on the grey scale ("Value" variable) were made. This dataset was analysed statistically via repeated measures ANOVA to determine the effect of each of the nine cleaning strategies in each of the five patients. A statistically significant difference in the efficacy of the cleaning strategies was detected. Specifically, rinsing with water alone was significantly less efficacious, and a combination of cationic detergent solution and ultrasonication was significantly more efficacious than the other methods (p aligners.

  7. Modeling Storm Surges Using Discontinuous Galerkin Methods

    Science.gov (United States)

    2016-06-01

    layer non-reflecting boundary condition (NRBC) on the right wall of the model. A NRBC is when an artificial boundary , B, is created, which truncates the... applications ,” Journal of Computational Physics, 2004. [30] P. L. Butzer and R. Weis, “On the lax equivalence theorem equipped with orders,” Journal of...closer to the shoreline. In our simulation, we also learned of the effects spurious waves can have on the results. Due to boundary conditions, a

  8. A Versatile Nonlinear Method for Predictive Modeling

    Science.gov (United States)

    Liou, Meng-Sing; Yao, Weigang

    2015-01-01

    As computational fluid dynamics techniques and tools become widely accepted for realworld practice today, it is intriguing to ask: what areas can it be utilized to its potential in the future. Some promising areas include design optimization and exploration of fluid dynamics phenomena (the concept of numerical wind tunnel), in which both have the common feature where some parameters are varied repeatedly and the computation can be costly. We are especially interested in the need for an accurate and efficient approach for handling these applications: (1) capturing complex nonlinear dynamics inherent in a system under consideration and (2) versatility (robustness) to encompass a range of parametric variations. In our previous paper, we proposed to use first-order Taylor expansion collected at numerous sampling points along a trajectory and assembled together via nonlinear weighting functions. The validity and performance of this approach was demonstrated for a number of problems with a vastly different input functions. In this study, we are especially interested in enhancing the method's accuracy; we extend it to include the second-orer Taylor expansion, which however requires a complicated evaluation of Hessian matrices for a system of equations, like in fluid dynamics. We propose a method to avoid these Hessian matrices, while maintaining the accuracy. Results based on the method are presented to confirm its validity.

  9. Diffusion in condensed matter methods, materials, models

    CERN Document Server

    Kärger, Jörg

    2005-01-01

    Diffusion as the process of particle transport due to stochastic movement is a phenomenon of crucial relevance for a large variety of processes and materials. This comprehensive, handbook- style survey of diffusion in condensed matter gives detailed insight into diffusion as the process of particle transport due to stochastic movement. Leading experts in the field describe in 23 chapters the different aspects of diffusion, covering microscopic and macroscopic experimental techniques and exemplary results for various classes of solids, liquids and interfaces as well as several theoretical concepts and models. Students and scientists in physics, chemistry, materials science, and biology will benefit from this detailed compilation.

  10. Continual integration method in the polaron model

    International Nuclear Information System (INIS)

    Kochetov, E.A.; Kuleshov, S.P.; Smondyrev, M.A.

    1981-01-01

    The article is devoted to the investigation of a polaron system on the base of a variational approach formulated on the language of continuum integration. The variational method generalizing the Feynman one for the case of the system pulse different from zero has been formulated. The polaron state has been investigated at zero temperature. A problem of the bound state of two polarons exchanging quanta of a scalar field as well as a problem of polaron scattering with an external field in the Born approximation have been considered. Thermodynamics of the polaron system has been investigated, namely, high-temperature expansions for mean energy and effective polaron mass have been studied [ru

  11. Modeling conflict : research methods, quantitative modeling, and lessons learned.

    Energy Technology Data Exchange (ETDEWEB)

    Rexroth, Paul E.; Malczynski, Leonard A.; Hendrickson, Gerald A.; Kobos, Peter Holmes; McNamara, Laura A.

    2004-09-01

    This study investigates the factors that lead countries into conflict. Specifically, political, social and economic factors may offer insight as to how prone a country (or set of countries) may be for inter-country or intra-country conflict. Largely methodological in scope, this study examines the literature for quantitative models that address or attempt to model conflict both in the past, and for future insight. The analysis concentrates specifically on the system dynamics paradigm, not the political science mainstream approaches of econometrics and game theory. The application of this paradigm builds upon the most sophisticated attempt at modeling conflict as a result of system level interactions. This study presents the modeling efforts built on limited data and working literature paradigms, and recommendations for future attempts at modeling conflict.

  12. Structural equation and log-linear modeling: a comparison of methods in the analysis of a study on caregivers' health

    Directory of Open Access Journals (Sweden)

    Rosenbaum Peter L

    2006-10-01

    Full Text Available Abstract Background In this paper we compare the results in an analysis of determinants of caregivers' health derived from two approaches, a structural equation model and a log-linear model, using the same data set. Methods The data were collected from a cross-sectional population-based sample of 468 families in Ontario, Canada who had a child with cerebral palsy (CP. The self-completed questionnaires and the home-based interviews used in this study included scales reflecting socio-economic status, child and caregiver characteristics, and the physical and psychological well-being of the caregivers. Both analytic models were used to evaluate the relationships between child behaviour, caregiving demands, coping factors, and the well-being of primary caregivers of children with CP. Results The results were compared, together with an assessment of the positive and negative aspects of each approach, including their practical and conceptual implications. Conclusion No important differences were found in the substantive conclusions of the two analyses. The broad confirmation of the Structural Equation Modeling (SEM results by the Log-linear Modeling (LLM provided some reassurance that the SEM had been adequately specified, and that it broadly fitted the data.

  13. "Method, system and storage medium for generating virtual brick models"

    DEFF Research Database (Denmark)

    2009-01-01

    An exemplary embodiment is a method for generating a virtual brick model. The virtual brick models are generated by users and uploaded to a centralized host system. Users can build virtual models themselves or download and edit another user's virtual brick models while retaining the identity...

  14. A Systematic Identification Method for Thermodynamic Property Modelling

    DEFF Research Database (Denmark)

    Ana Perederic, Olivia; Cunico, Larissa; Sarup, Bent

    2017-01-01

    In this work, a systematic identification method for thermodynamic property modelling is proposed. The aim of the method is to improve the quality of phase equilibria prediction by group contribution based property prediction models. The method is applied to lipid systems where the Original UNIFAC...... model is used. Using the proposed method for estimating the interaction parameters using only VLE data, a better phase equilibria prediction for both VLE and SLE was obtained. The results were validated and compared with the original model performance...

  15. Laser filamentation mathematical methods and models

    CERN Document Server

    Lorin, Emmanuel; Moloney, Jerome

    2016-01-01

    This book is focused on the nonlinear theoretical and mathematical problems associated with ultrafast intense laser pulse propagation in gases and in particular, in air. With the aim of understanding the physics of filamentation in gases, solids, the atmosphere, and even biological tissue, specialists in nonlinear optics and filamentation from both physics and mathematics attempt to rigorously derive and analyze relevant non-perturbative models. Modern laser technology allows the generation of ultrafast (few cycle) laser pulses, with intensities exceeding the internal electric field in atoms and molecules (E=5x109 V/cm or intensity I = 3.5 x 1016 Watts/cm2 ). The interaction of such pulses with atoms and molecules leads to new, highly nonlinear nonperturbative regimes, where new physical phenomena, such as High Harmonic Generation (HHG), occur, and from which the shortest (attosecond - the natural time scale of the electron) pulses have been created. One of the major experimental discoveries in this nonlinear...

  16. Models and methods of emotional concordance.

    Science.gov (United States)

    Hollenstein, Tom; Lanteigne, Dianna

    2014-04-01

    Theories of emotion generally posit the synchronized, coordinated, and/or emergent combination of psychophysiological, cognitive, and behavioral components of the emotion system--emotional concordance--as a functional definition of emotion. However, the empirical support for this claim has been weak or inconsistent. As an introduction to this special issue on emotional concordance, we consider three domains of explanations as to why this theory-data gap might exist. First, theory may need to be revised to more accurately reflect past research. Second, there may be moderating factors such as emotion regulation, context, or individual differences that have obscured concordance. Finally, the methods typically used to test theory may be inadequate. In particular, we review a variety of potential issues: intensity of emotions elicited in the laboratory, nonlinearity, between- versus within-subject associations, the relative timing of components, bivariate versus multivariate approaches, and diversity of physiological processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Theoretical methods and models for mechanical properties of soft biomaterials

    Directory of Open Access Journals (Sweden)

    Zhonggang Feng

    2017-06-01

    Full Text Available We review the most commonly used theoretical methods and models for the mechanical properties of soft biomaterials, which include phenomenological hyperelastic and viscoelastic models, structural biphasic and network models, and the structural alteration theory. We emphasize basic concepts and recent developments. In consideration of the current progress and needs of mechanobiology, we introduce methods and models for tackling micromechanical problems and their applications to cell biology. Finally, the challenges and perspectives in this field are discussed.

  18. Surgery on spinal epidural metastases (SEM) in renal cell carcinoma: a plea for a new paradigm.

    Science.gov (United States)

    Bakker, Nicolaas A; Coppes, Maarten H; Vergeer, Rob A; Kuijlen, Jos M A; Groen, Rob J M

    2014-09-01

    Prediction models for outcome of decompressive surgical resection of spinal epidural metastases (SEM) have in common that they have been developed for all types of SEM, irrespective of the type of primary tumor. It is our experience in clinical practice, however, that these models often fail to accurately predict outcome in the individual patient. To investigate whether decision making could be optimized by applying tumor-specific prediction models. For the proof of concept, we analyzed patients with SEM from renal cell carcinoma that we have operated on. Retrospective chart analysis 2006 to 2012. Twenty-one consecutive patients with symptomatic SEM of renal cell carcinoma. Predictive factors for survival. Next to established predictive factors for survival, we analyzed the predictive value of the Motzer criteria in these patients. The Motzer criteria comprise a specific and validated risk model for survival in patients with renal cell carcinoma. After multivariable analysis, only Motzer intermediate (hazard ratio [HR] 17.4, 95% confidence interval [CI] 1.82-166, p=.01) and high risk (HR 39.3, 95% CI 3.10-499, p=.005) turned out to be significantly associated with survival in patients with renal cell carcinoma that we have operated on. In this study, we have demonstrated that decision making could have been optimized by implementing the Motzer criteria next to established prediction models. We, therefore, suggest that in future, in patients with SEM from renal cell carcinoma, the Motzer criteria are also taken into account. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Canticum Novum: música sem palavras e palavras sem som no pensamento de Santo Agostinho

    Directory of Open Access Journals (Sweden)

    Lorenzo Mammì

    2000-04-01

    Full Text Available NO De Magistro, Santo Agostinho coloca a reza e o canto numa posição similar, à margem das funções imediatamente comunicativas da linguagem. A reflexão agostiniana sobre a reza se baseia nos hábitos cristãos da leitura, da oração e da meditação silenciosas. Há sobre o canto, na prática igualmente inovadora do jubilus, melodia sem palavra destinada aos momentos mais intensos e gaudiosos da liturgia. A oração silenciosa e o jubilus são temas recorrentes da literatura patrística, mas Agostinho os aborda de maneira original, desenhando, a partir das palavras sem som da oração e do som sem palavra do jubilus, o perfil de um discurso interior, que não se destina aos homens, mas a Deus.IN HIS De Magistro Saint Augustine places prayer and song on a similar level, alongside the language immediately communicative functions. His considerations on prayer are grounded on the Christian habits of silent reading, prayer and meditation; those on song, on the equally innovating practice called jubilus, which is melody without words designed for the intensest and most joyous liturgical moments. Silent prayer and jubilus are recurring topics in patristic literature, but Augustine deals with them in an original way, drawing from the soundless words of prayer and the wordless sound of jubilus an inner discourse, addressed not to men but to God.

  20. METHODICAL MODEL FOR TEACHING BASIC SKI TURN

    Directory of Open Access Journals (Sweden)

    Danijela Kuna

    2013-07-01

    Full Text Available With the aim of forming an expert model of the most important operators for basic ski turn teaching in ski schools, an experiment was conducted on a sample of 20 ski experts from different countries (Croatia, Bosnia and Herzegovina and Slovenia. From the group of the most commonly used operators for teaching basic ski turn the experts picked the 6 most important: uphill turn and jumping into snowplough, basic turn with hand sideways, basic turn with clapping, ski poles in front, ski poles on neck, uphill turn with active ski guiding. Afterwards, ranking and selection of the most efficient operators was carried out. Due to the set aim of research, a Chi square test was used, as well as the differences between frequencies of chosen operators, differences between values of the most important operators and differences between experts due to their nationality. Statistically significant differences were noticed between frequencies of chosen operators (c2= 24.61; p=0.01, while differences between values of the most important operators were not obvious (c2= 1.94; p=0.91. Meanwhile, the differences between experts concerning thier nationality were only noticeable in the expert evaluation of ski poles on neck operator (c2=7.83; p=0.02. Results of current research are reflected in obtaining useful information about methodological priciples of learning basic ski turn organization in ski schools.

  1. Filler segmentation of SEM paper images based on mathematical morphology.

    Science.gov (United States)

    Ait Kbir, M; Benslimane, Rachid; Princi, Elisabetta; Vicini, Silvia; Pedemonte, Enrico

    2007-07-01

    Recent developments in microscopy and image processing have made digital measurements on high-resolution images of fibrous materials possible. This helps to gain a better understanding of the structure and other properties of the material at micro level. In this paper SEM image segmentation based on mathematical morphology is proposed. In fact, paper models images (Whatman, Murillo, Watercolor, Newsprint paper) selected in the context of the Euro Mediterranean PaperTech Project have different distributions of fibers and fillers, caused by the presence of SiAl and CaCO3 particles. It is a microscopy challenge to make filler particles in the sheet distinguishable from the other components of the paper surface. This objectif is reached here by using switable strutural elements and mathematical morphology operators.

  2. SEM-EDX--a useful tool for forensic examinations

    International Nuclear Information System (INIS)

    Zadora, G.; Brozek-Mucha, Z.

    2003-01-01

    There are two main aims of forensic examination of the physical evidences. The first aim is comparison of the evidence with the reference material (called discrimination). The task is to find out whether they could have come from the same object. The second aim, when there is no comparative material available, is a classification of the evidence sample into a group of objects taking into account its specific chemical and physical properties. Scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX) is a powerful tool for forensic scientists to classify and discriminate evidence material because they can simultaneously examine the morphology and the elemental composition of objects. Moreover, the obtained results could be enhanced using some methods of chemometric analysis. A few examples of problems related to the classification and discrimination of selected types of microtraces are presented

  3. Estimating Model Probabilities using Thermodynamic Markov Chain Monte Carlo Methods

    Science.gov (United States)

    Ye, M.; Liu, P.; Beerli, P.; Lu, D.; Hill, M. C.

    2014-12-01

    Markov chain Monte Carlo (MCMC) methods are widely used to evaluate model probability for quantifying model uncertainty. In a general procedure, MCMC simulations are first conducted for each individual model, and MCMC parameter samples are then used to approximate marginal likelihood of the model by calculating the geometric mean of the joint likelihood of the model and its parameters. It has been found the method of evaluating geometric mean suffers from the numerical problem of low convergence rate. A simple test case shows that even millions of MCMC samples are insufficient to yield accurate estimation of the marginal likelihood. To resolve this problem, a thermodynamic method is used to have multiple MCMC runs with different values of a heating coefficient between zero and one. When the heating coefficient is zero, the MCMC run is equivalent to a random walk MC in the prior parameter space; when the heating coefficient is one, the MCMC run is the conventional one. For a simple case with analytical form of the marginal likelihood, the thermodynamic method yields more accurate estimate than the method of using geometric mean. This is also demonstrated for a case of groundwater modeling with consideration of four alternative models postulated based on different conceptualization of a confining layer. This groundwater example shows that model probabilities estimated using the thermodynamic method are more reasonable than those obtained using the geometric method. The thermodynamic method is general, and can be used for a wide range of environmental problem for model uncertainty quantification.

  4. Comparison of Transmission Line Methods for Surface Acoustic Wave Modeling

    Science.gov (United States)

    Wilson, William; Atkinson, Gary

    2009-01-01

    Surface Acoustic Wave (SAW) technology is low cost, rugged, lightweight, extremely low power and can be used to develop passive wireless sensors. For these reasons, NASA is investigating the use of SAW technology for Integrated Vehicle Health Monitoring (IVHM) of aerospace structures. To facilitate rapid prototyping of passive SAW sensors for aerospace applications, SAW models have been developed. This paper reports on the comparison of three methods of modeling SAWs. The three models are the Impulse Response Method (a first order model), and two second order matrix methods; the conventional matrix approach, and a modified matrix approach that is extended to include internal finger reflections. The second order models are based upon matrices that were originally developed for analyzing microwave circuits using transmission line theory. Results from the models are presented with measured data from devices. Keywords: Surface Acoustic Wave, SAW, transmission line models, Impulse Response Method.

  5. Modeling shallow water flows using the discontinuous Galerkin method

    CERN Document Server

    Khan, Abdul A

    2014-01-01

    Replacing the Traditional Physical Model Approach Computational models offer promise in improving the modeling of shallow water flows. As new techniques are considered, the process continues to change and evolve. Modeling Shallow Water Flows Using the Discontinuous Galerkin Method examines a technique that focuses on hyperbolic conservation laws and includes one-dimensional and two-dimensional shallow water flows and pollutant transports. Combines the Advantages of Finite Volume and Finite Element Methods This book explores the discontinuous Galerkin (DG) method, also known as the discontinuous finite element method, in depth. It introduces the DG method and its application to shallow water flows, as well as background information for implementing and applying this method for natural rivers. It considers dam-break problems, shock wave problems, and flows in different regimes (subcritical, supercritical, and transcritical). Readily Adaptable to the Real World While the DG method has been widely used in the fie...

  6. An Expectation-Maximization Method for Calibrating Synchronous Machine Models

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Da; Zhou, Ning; Lu, Shuai; Lin, Guang

    2013-07-21

    The accuracy of a power system dynamic model is essential to its secure and efficient operation. Lower confidence in model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, this paper proposes an expectation-maximization (EM) method to calibrate the synchronous machine model using phasor measurement unit (PMU) data. First, an extended Kalman filter (EKF) is applied to estimate the dynamic states using measurement data. Then, the parameters are calculated based on the estimated states using maximum likelihood estimation (MLE) method. The EM method iterates over the preceding two steps to improve estimation accuracy. The proposed EM method’s performance is evaluated using a single-machine infinite bus system and compared with a method where both state and parameters are estimated using an EKF method. Sensitivity studies of the parameter calibration using EM method are also presented to show the robustness of the proposed method for different levels of measurement noise and initial parameter uncertainty.

  7. SEM analysis of ionizing radiation effects in linear integrated circuits. [Scanning Electron Microscope

    Science.gov (United States)

    Stanley, A. G.; Gauthier, M. K.

    1977-01-01

    A successful diagnostic technique was developed using a scanning electron microscope (SEM) as a precision tool to determine ionization effects in integrated circuits. Previous SEM methods radiated the entire semiconductor chip or major areas. The large area exposure methods do not reveal the exact components which are sensitive to radiation. To locate these sensitive components a new method was developed, which consisted in successively irradiating selected components on the device chip with equal doses of electrons /10 to the 6th rad (Si)/, while the whole device was subjected to representative bias conditions. A suitable device parameter was measured in situ after each successive irradiation with the beam off.

  8. The importance of scanning electron microscopy (sem in taxonomy and morphology of Chironomidae (Diptera

    Directory of Open Access Journals (Sweden)

    Andrzej Kownacki

    2015-07-01

    Full Text Available The paper reports on the value of scanning electron microscopy (SEM in the taxonomy and morphology of Chironomidae. This method has been relatively rarely used in Chironomidae studies. Our studies suggest that the SEM method provides a lot of new information. For example, the plastron plate of the thoracic horn of Macropelopia nebulosa (Meigen under light microscopy is visible as points, while under SEM we have found that it consists of a reticular structure with holes. By using SEM a more precise picture of the body structure of Chironomidae can be revealed. It allows researchers to explain inconsistencies in the existing descriptions of species. Another advantage of the SEM method is obtaining spatial images of the body and organs of Chironomidae. However, the SEM method also has some limitations. The main problem is dirt or debris (e.g. algae, mud, secretions, mucus, bacteria, etc., which often settles on the external surface of structures, especially those which are uneven or covered with hair. The dirt should be removed after collection of chironomid material because if left in place it can become chemically fixed to various surfaces. It unnecessarily remains at the surface and final microscopic images may contain artifacts that obscure chironomid structures being investigated. In this way many details of the surface are thus unreadable. The results reported here indicate that SEM examination helps us to identify new morphological features and details that will facilitate the identification of species of Chironomidae and may help to clarify the function of various parts of the body. Fast development of electron microscope technique allows us to learn more about structure of different organisms.

  9. On Angular Sampling Methods for 3-D Spatial Channel Models

    DEFF Research Database (Denmark)

    Fan, Wei; Jämsä, Tommi; Nielsen, Jesper Ødum

    2015-01-01

    This paper discusses generating three dimensional (3D) spatial channel models with emphasis on the angular sampling methods. Three angular sampling methods, i.e. modified uniform power sampling, modified uniform angular sampling, and random pairing methods are proposed and investigated in detail....... The random pairing method, which uses only twenty sinusoids in the ray-based model for generating the channels, presents good results if the spatial channel cluster is with a small elevation angle spread. For spatial clusters with large elevation angle spreads, however, the random pairing method would fail...... and the other two methods should be considered....

  10. Comparative SEM analysis of nine F22 aligner cleaning strategies

    Directory of Open Access Journals (Sweden)

    Luca Lombardo

    2017-09-01

    Full Text Available Abstract Background The orthodontics industry has paid great attention to the aesthetics of orthodontic appliances, seeking to make them as invisible as possible. There are several advantages to clear aligner systems, including aesthetics, comfort, chairside time reduction, and the fact that they can be removed for meals and oral hygiene procedures. Methods Five patients were each given a series of F22 aligners, each to be worn for 14 days and nights, with the exception of meal and brushing times. Patients were instructed to clean each aligner using a prescribed strategy, and sections of the used aligners were observed under SEM. One grey-scale SEM image was saved per aligner in JPEG format with an 8-bit colour depth, and a total of 45 measurements on the grey scale (“Value” variable were made. This dataset was analysed statistically via repeated measures ANOVA to determine the effect of each of the nine cleaning strategies in each of the five patients. Results A statistically significant difference in the efficacy of the cleaning strategies was detected. Specifically, rinsing with water alone was significantly less efficacious, and a combination of cationic detergent solution and ultrasonication was significantly more efficacious than the other methods (p < 0.05. Conclusions Of the nine cleaning strategies examined, only that involving 5 min of ultrasonication at 42 k Hz combined with a 0.3% germicidal cationic detergent was observed to be statistically effective at removing the bacterial biofilm from the surface of F22 aligners.

  11. Qualidade de vida de pessoas colostomizadas com e sem uso de métodos de controle intestinal Calidad de vida de personas colostomizadas con o sin uso de métodos de control intestinal Quality of life of the colostomized person with or without use of methods of bowel control

    Directory of Open Access Journals (Sweden)

    Isabel Umbelina Ribeiro Cesaretti

    2010-02-01

    Full Text Available OBJETIVO: Avaliar e comparar a qualidade de vida (QV de pessoas colostomizadas que utilizam e não utilizam os métodos de controle intestinal (MCI, ou seja, a irrigação e o sistema oclusor da colostomia, considerando a hipótese de que aquelas que os utilizam têm melhor QV. Método: O estudo foi desenvolvido no Ambulatório do Hospital Heliópolis, após a aprovação do projeto pelo Comitê de Ética, usando o WHOQoL-abreviado. A amostra foi constituída de dois grupos: 50 pessoas colostomizadas usando os dois MCI e 50, sem os MCI. Resultados: A QV do Grupo com MCI foi significativamente melhor em todos os Domínios e na QV Geral do que daquelas do Grupo sem MCI. Conclusão: O estudo confirmou a hipótese de que a QV do Grupo com MCI é melhor do que a do Grupo sem MCI.OBJETIVO: Evaluar y comparar la calidad de vida (CV de las personas colostomizadas, con y sin el uso de los métodos de control intestinal (MCI, es decir, la irrigación y el sistema obturador de la colostomia, teniendo en cuenta la hipótesis de que aquellas que los utilizan tienen mejor CV. Método: El estudio fue llevado a cabo en el Ambulatorio del Hospital Heliópolis después de la aprobación del proyecto por lo Comité de Ética, usando el WHOQoL-bref. La muestra fue constituida de dos grupos: 50 personas colostomizadas usando los dos MCI y 50, sin los MCI. Resultados: Las personas del Grupo con MCI tenían CV perceptiblemente mejor, siendo eso observado en todos los Dominios y en la CV General, que aquellas del Grupo sin MCI. Conclusión: El estudio confirmo la hipótesis que la CV del Grupo con MCI es mejor que la del Grupo sin MCI.OBJECTIVE: To evaluate and to compare the quality of life (QoL of colostomy people, using or not using the bowel control methods (BCM, in other words, the colostomy irrigation and the plug system, considering the hypothesis that people who used them had better QoL. Method: This study was carried out in the Heliópolis Hospital Outpatient

  12. An iterative method for accelerated degradation testing data of smart electricity meter

    Science.gov (United States)

    Wang, Xiaoming; Xie, Jinzhe

    2017-01-01

    In order to evaluate the performance of smart electricity meter (SEM), we must spend a lot of time censoring its status. For example, if we assess to the meter stability of the SEM which needs several years at least according to the standards. So accelerated degradation testing (ADT) is a useful method to assess the performance of the SEM. As we known, the Wiener process is a prevalent method to interpret the performance degradation. This paper proposes an iterative method for ADT data of SEM. The simulation study verifies the application and superiority of the proposed model than other ADT methods.

  13. Methods for model selection in applied science and engineering.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr.

    2004-10-01

    Mathematical models are developed and used to study the properties of complex systems and/or modify these systems to satisfy some performance requirements in just about every area of applied science and engineering. A particular reason for developing a model, e.g., performance assessment or design, is referred to as the model use. Our objective is the development of a methodology for selecting a model that is sufficiently accurate for an intended use. Information on the system being modeled is, in general, incomplete, so that there may be two or more models consistent with the available information. The collection of these models is called the class of candidate models. Methods are developed for selecting the optimal member from a class of candidate models for the system. The optimal model depends on the available information, the selected class of candidate models, and the model use. Classical methods for model selection, including the method of maximum likelihood and Bayesian methods, as well as a method employing a decision-theoretic approach, are formulated to select the optimal model for numerous applications. There is no requirement that the candidate models be random. Classical methods for model selection ignore model use and require data to be available. Examples are used to show that these methods can be unreliable when data is limited. The decision-theoretic approach to model selection does not have these limitations, and model use is included through an appropriate utility function. This is especially important when modeling high risk systems, where the consequences of using an inappropriate model for the system can be disastrous. The decision-theoretic method for model selection is developed and applied for a series of complex and diverse applications. These include the selection of the: (1) optimal order of the polynomial chaos approximation for non-Gaussian random variables and stationary stochastic processes, (2) optimal pressure load model to be

  14. SELECT NUMERICAL METHODS FOR MODELING THE DYNAMICS SYSTEMS

    Directory of Open Access Journals (Sweden)

    Tetiana D. Panchenko

    2016-07-01

    Full Text Available The article deals with the creation of methodical support for mathematical modeling of dynamic processes in elements of the systems and complexes. As mathematical models ordinary differential equations have been used. The coefficients of the equations of the models can be nonlinear functions of the process. The projection-grid method is used as the main tool. It has been described iterative method algorithms taking into account the approximate solution prior to the first iteration and proposed adaptive control computing process. The original method of estimation error in the calculation solutions as well as for a given level of error of the technique solutions purpose adaptive method for solving configuration parameters is offered. A method for setting an adaptive method for solving the settings for a given level of error is given. The proposed method can be used for distributed computing.

  15. Comparative analysis of various methods for modelling permanent magnet machines

    NARCIS (Netherlands)

    Ramakrishnan, K.; Curti, M.; Zarko, D.; Mastinu, G.; Paulides, J.J.H.; Lomonova, E.A.

    2017-01-01

    In this paper, six different modelling methods for permanent magnet (PM) electric machines are compared in terms of their computational complexity and accuracy. The methods are based primarily on conformal mapping, mode matching, and harmonic modelling. In the case of conformal mapping, slotted air

  16. Feature evaluation of complex hysteresis smoothing and its practical applications to noisy SEM images.

    Science.gov (United States)

    Suzuki, Kazuhiko; Oho, Eisaku

    2013-01-01

    Quality of a scanning electron microscopy (SEM) image is strongly influenced by noise. This is a fundamental drawback of the SEM instrument. Complex hysteresis smoothing (CHS) has been previously developed for noise removal of SEM images. This noise removal is performed by monitoring and processing properly the amplitude of the SEM signal. As it stands now, CHS may not be so utilized, though it has several advantages for SEM. For example, the resolution of image processed by CHS is basically equal to that of the original image. In order to find wide application of the CHS method in microscopy, the feature of CHS, which has not been so clarified until now is evaluated correctly. As the application of the result obtained by the feature evaluation, cursor width (CW), which is the sole processing parameter of CHS, is determined more properly using standard deviation of noise Nσ. In addition, disadvantage that CHS cannot remove the noise with excessively large amplitude is improved by a certain postprocessing. CHS is successfully applicable to SEM images with various noise amplitudes. © Wiley Periodicals, Inc.

  17. Advanced methods of solid oxide fuel cell modeling

    CERN Document Server

    Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

    2011-01-01

    Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

  18. Extending product modeling methods for integrated product development

    DEFF Research Database (Denmark)

    Bonev, Martin; Wörösch, Michael; Hauksdóttir, Dagný

    2013-01-01

    Despite great efforts within the modeling domain, the majority of methods often address the uncommon design situation of an original product development. However, studies illustrate that development tasks are predominantly related to redesigning, improving, and extending already existing products...... and PVM methods, in a presented Product Requirement Development model some of the individual drawbacks of each method could be overcome. Based on the UML standard, the model enables the representation of complex hierarchical relationships in a generic product model. At the same time it uses matrix....... Updated design requirements have then to be made explicit and mapped against the existing product architecture. In this paper, existing methods are adapted and extended through linking updated requirements to suitable product models. By combining several established modeling techniques, such as the DSM...

  19. Estimation methods for nonlinear state-space models in ecology

    DEFF Research Database (Denmark)

    Pedersen, Martin Wæver; Berg, Casper Willestofte; Thygesen, Uffe Høgsbro

    2011-01-01

    The use of nonlinear state-space models for analyzing ecological systems is increasing. A wide range of estimation methods for such models are available to ecologists, however it is not always clear, which is the appropriate method to choose. To this end, three approaches to estimation in the theta...... logistic model for population dynamics were benchmarked by Wang (2007). Similarly, we examine and compare the estimation performance of three alternative methods using simulated data. The first approach is to partition the state-space into a finite number of states and formulate the problem as a hidden...... Markov model (HMM). The second method uses the mixed effects modeling and fast numerical integration framework of the AD Model Builder (ADMB) open-source software. The third alternative is to use the popular Bayesian framework of BUGS. The study showed that state and parameter estimation performance...

  20. Quality index method (QIM application on shef life estimation of skinned fillets of Nile tilapia (Oreochromis niloticus kept in iceAplicação do método do índice de qualidade (MIQ para o estudo da vida útil de filés de tilápia do Nilo (Oreochromis niloticus sem pele, armazenados em gelo

    Directory of Open Access Journals (Sweden)

    Karoline Mikaelle de Paiva Soares

    2012-12-01

    Full Text Available The objective of this study was to develop the Quality Index Method (QIM for skinned fillets from farmed Nile tilapia (Oreochromis niloticus, and apply it in the establishment of its shelf life. The skinned fillets (120 g in average were kept in boxes with ice in the proportion of 1:1 (fillet:ice under average temperature of 0°C and stored at refrigeration chamber (4°C during 18 days. To evaluate the freshness during storage time sensory analysis (QIM and physicochemical (pH and TVB-N were performed every 72 hours from time zero, in triplicate. The maximum life of the Nile tilapia fillet in ice was estimated at 15 days. The MIQ was considered effective in evaluating the freshness of the Nile tilapia, since the sensory rejection by MIQ was determinant in the shelf life establishment. O objetivo do presente trabalho foi desenvolver o Método do Índice de Qualidade (MIQ para filé sem pele de tilápia do Nilo (Oreochromis niloticus, cultivada, e aplicá-lo no estabelecimento da sua vida útil. Os filés (média de 120 g cada foram mantidos em caixas com gelo na proporção de 1:1 (filé:gelo na temperatura média de 0°C e armazenados em câmaras de refrigeração (4°C por 18 dias. Para avaliar o frescor durante o armazenamento, realizaram-se análises sensoriais (MIQ e físico-químicas (pH e Nitrogênio das Bases Voláteis Totais a cada 72 horas, a partir do tempo zero, em triplicata. A vida útil máxima do filé sem pele de tilápia do Nilo, em gelo, foi estimada em 15 dias. O MIQ foi considerado eficiente na avaliação do frescor da tilápia do Nilo, já que a rejeição sensorial pelo MIQ foi determinante no estabelecimento da vida de prateleira.

  1. Architecture oriented modeling and simulation method for combat mission profile

    Directory of Open Access Journals (Sweden)

    CHEN Xia

    2017-05-01

    Full Text Available In order to effectively analyze the system behavior and system performance of combat mission profile, an architecture-oriented modeling and simulation method is proposed. Starting from the architecture modeling,this paper describes the mission profile based on the definition from National Military Standard of China and the US Department of Defense Architecture Framework(DoDAFmodel, and constructs the architecture model of the mission profile. Then the transformation relationship between the architecture model and the agent simulation model is proposed to form the mission profile executable model. At last,taking the air-defense mission profile as an example,the agent simulation model is established based on the architecture model,and the input and output relations of the simulation model are analyzed. It provides method guidance for the combat mission profile design.

  2. Modelling a coal subcrop using the impedance method

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.A.; Thiel, D.V.; O' Keefe, S.G. [Griffith University, Nathan, Qld. (Australia). School of Microelectronic Engineering

    2000-07-01

    An impedance model was generated for two coal subcrops in the Biloela and Middlemount areas (Queensland, Australia). The model results were compared with actual surface impedance data. It was concluded that the impedance method satisfactorily modelled the surface response of the coal subcrops in two dimensions. There were some discrepancies between the field data and the model results, due to factors such as the method of discretization of the solution space in the impedance model and the lack of consideration of the three-dimensional nature of the coal outcrops. 10 refs., 8 figs.

  3. Systems and methods for modeling and analyzing networks

    Science.gov (United States)

    Hill, Colin C; Church, Bruce W; McDonagh, Paul D; Khalil, Iya G; Neyarapally, Thomas A; Pitluk, Zachary W

    2013-10-29

    The systems and methods described herein utilize a probabilistic modeling framework for reverse engineering an ensemble of causal models, from data and then forward simulating the ensemble of models to analyze and predict the behavior of the network. In certain embodiments, the systems and methods described herein include data-driven techniques for developing causal models for biological networks. Causal network models include computational representations of the causal relationships between independent variables such as a compound of interest and dependent variables such as measured DNA alterations, changes in mRNA, protein, and metabolites to phenotypic readouts of efficacy and toxicity.

  4. Monte Carlo methods and models in finance and insurance

    CERN Document Server

    Korn, Ralf; Kroisandt, Gerald

    2010-01-01

    Offering a unique balance between applications and calculations, Monte Carlo Methods and Models in Finance and Insurance incorporates the application background of finance and insurance with the theory and applications of Monte Carlo methods. It presents recent methods and algorithms, including the multilevel Monte Carlo method, the statistical Romberg method, and the Heath-Platen estimator, as well as recent financial and actuarial models, such as the Cheyette and dynamic mortality models. The authors separately discuss Monte Carlo techniques, stochastic process basics, and the theoretical background and intuition behind financial and actuarial mathematics, before bringing the topics together to apply the Monte Carlo methods to areas of finance and insurance. This allows for the easy identification of standard Monte Carlo tools and for a detailed focus on the main principles of financial and insurance mathematics. The book describes high-level Monte Carlo methods for standard simulation and the simulation of...

  5. Two Undergraduate Process Modeling Courses Taught Using Inductive Learning Methods

    Science.gov (United States)

    Soroush, Masoud; Weinberger, Charles B.

    2010-01-01

    This manuscript presents a successful application of inductive learning in process modeling. It describes two process modeling courses that use inductive learning methods such as inquiry learning and problem-based learning, among others. The courses include a novel collection of multi-disciplinary complementary process modeling examples. They were…

  6. An automatic and effective parameter optimization method for model tuning

    Directory of Open Access Journals (Sweden)

    T. Zhang

    2015-11-01

    simulation results show that the optimum combination of these parameters determined using this method is able to improve the model's overall performance by 9 %. The proposed methodology and software framework can be easily applied to other GCMs to speed up the model development process, especially regarding unavoidable comprehensive parameter tuning during the model development stage.

  7. Markov chain Monte Carlo methods in directed graphical models

    DEFF Research Database (Denmark)

    Højbjerre, Malene

    Directed graphical models present data possessing a complex dependence structure, and MCMC methods are computer-intensive simulation techniques to approximate high-dimensional intractable integrals, which emerge in such models with incomplete data. MCMC computations in directed graphical models h...

  8. Solving the nuclear shell model with an algebraic method

    International Nuclear Information System (INIS)

    Feng, D.H.; Pan, X.W.; Guidry, M.

    1997-01-01

    We illustrate algebraic methods in the nuclear shell model through a concrete example, the fermion dynamical symmetry model (FDSM). We use this model to introduce important concepts such as dynamical symmetry, symmetry breaking, effective symmetry, and diagonalization within a higher-symmetry basis. (orig.)

  9. Modeling of Landslides with the Material Point Method

    DEFF Research Database (Denmark)

    Andersen, Søren Mikkel; Andersen, Lars

    2008-01-01

    A numerical model for studying the dynamic evolution of landslides is presented. The numerical model is based on the Generalized Interpolation Material Point Method. A simplified slope with a house placed on top is analysed. An elasto-plastic material model based on the Mohr-Coulomb yield criterion...

  10. Modelling of Landslides with the Material-point Method

    DEFF Research Database (Denmark)

    Andersen, Søren; Andersen, Lars

    2009-01-01

    A numerical model for studying the dynamic evolution of landslides is presented. The numerical model is based on the Generalized Interpolation Material Point Method. A simplified slope with a house placed on top is analysed. An elasto-plastic material model based on the Mohr-Coulomb yield criterion...

  11. Unsteady panel method for complex configurations including wake modeling

    CSIR Research Space (South Africa)

    Van Zyl, Lourens H

    2008-01-01

    Full Text Available implementations of the DLM are however not very versatile in terms of geometries that can be modeled. The ZONA6 code offers a versatile surface panel body model including a separated wake model, but uses a pressure panel method for lifting surfaces. This paper...

  12. Design of nuclear power generation plants adopting model engineering method

    International Nuclear Information System (INIS)

    Waki, Masato

    1983-01-01

    The utilization of model engineering as the method of design has begun about ten years ago in nuclear power generation plants. By this method, the result of design can be confirmed three-dimensionally before actual production, and it is the quick and sure method to meet the various needs in design promptly. The adoption of models aims mainly at the improvement of the quality of design since the high safety is required for nuclear power plants in spite of the complex structure. The layout of nuclear power plants and piping design require the model engineering to arrange rationally enormous quantity of things in a limited period. As the method of model engineering, there are the use of check models and of design models, and recently, the latter method has been mainly taken. The procedure of manufacturing models and engineering is explained. After model engineering has been completed, the model information must be expressed in drawings, and the automation of this process has been attempted by various methods. The computer processing of design is in progress, and its role is explained (CAD system). (Kako, I.)

  13. Minimal resin embedding of multicellular specimens for targeted FIB-SEM imaging.

    Science.gov (United States)

    Schieber, Nicole L; Machado, Pedro; Markert, Sebastian M; Stigloher, Christian; Schwab, Yannick; Steyer, Anna M

    2017-01-01

    Correlative light and electron microscopy (CLEM) is a powerful tool to perform ultrastructural analysis of targeted tissues or cells. The large field of view of the light microscope (LM) enables quick and efficient surveys of the whole specimen. It is also compatible with live imaging, giving access to functional assays. CLEM protocols take advantage of the features to efficiently retrace the position of targeted sites when switching from one modality to the other. They more often rely on anatomical cues that are visible both by light and electron microscopy. We present here a simple workflow where multicellular specimens are embedded in minimal amounts of resin, exposing their surface topology that can be imaged by scanning electron microscopy (SEM). LM and SEM both benefit from a large field of view that can cover whole model organisms. As a result, targeting specific anatomic locations by focused ion beam-SEM (FIB-SEM) tomography becomes straightforward. We illustrate this application on three different model organisms, used in our laboratory: the zebrafish embryo Danio rerio, the marine worm Platynereis dumerilii, and the dauer larva of the nematode Caenorhabditis elegans. Here we focus on the experimental steps to reduce the amount of resin covering the samples and to image the specimens inside an FIB-SEM. We expect this approach to have widespread applications for volume electron microscopy on multiple model organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Refinement of Monte Carlo simulations of electron-specimen interaction in low-voltage SEM

    International Nuclear Information System (INIS)

    Kieft, Erik; Bosch, Eric

    2008-01-01

    A Monte Carlo tool is presented for the simulation of secondary electron (SE) emission in a scanning electron microscope (SEM). The tool is based on the Geant4 platform of CERN. The modularity of this platform makes it comparatively easy to add and test individual physical models. Our aim has been to develop a flexible and generally applicable tool, while at the same time including a good description of low-energy (<50 eV) interactions of electrons with matter. To this end we have combined Mott cross-sections with phonon-scattering based cross-sections for the elastic scattering of electrons, and we have adopted a dielectric function theory approach for inelastic scattering and generation of SEs. A detailed model of the electromagnetic fields from an actual SEM column has been included in the tool for ray tracing of secondary and backscattered electrons. Our models have been validated against experimental results through comparison of the simulation results with experimental yields, SE spectra and SEM images. It is demonstrated that the resulting simulation package is capable of quantitatively predicting experimental SEM images and is an important tool in building a deeper understanding of SEM imaging.

  15. Method of modeling the cognitive radio using Opnet Modeler

    OpenAIRE

    Yakovenko, I. V.; Poshtarenko, V. M.; Kostenko, R. V.

    2012-01-01

    This article is a review of the first wireless standard based on cognitive radio networks. The necessity of wireless networks based on the technology of cognitive radio. An example of the use of standard IEEE 802.22 in Wimax network through which was implemented in the simulation software environment Opnet Modeler. Schedules to check the performance of HTTP and FTP protocols CR network. Simulation results justify the use of standard IEEE 802.22 in wireless networks. Ця стаття являє собою о...

  16. Does Your SEM Really Tell the Truth?-How Would You Know? Part 4: Charging and its Mitigation.

    Science.gov (United States)

    Postek, Michael T; Vladár, András E

    2015-01-01

    This is the fourth part of a series of tutorial papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST and other research institutions. Scanned particle beam instruments, especially the scanning electron microscope (SEM), have gone through tremendous evolution to become indispensable tools for many and diverse scientifc and industrial applications. These improvements have significantly enhanced their performance and made them far easier to operate. But, the ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the apparent need for extensive operator training. Unfortunately, this has led to the idea that the SEM is just another expensive "digital camera" or another peripheral device connected to a computer and that all of the problems in obtaining good quality images and data have been solved. Hence, one using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and believing that, everything one sees on the micrograph is always correct. But, as described in this and the earlier papers, this may not be the case. Care must always be taken when reliable quantitative data are being sought. The first paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modeling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper has discussed another major issue confronting the microscopist: specimen contamination and methods to eliminate it. The third paper discussed mechanical vibration and stage drift and some useful solutions to mitigate the problems caused by them, and here, in this the fourth contribution, the issues related to specimen "charging" and its mitigation are discussed relative to

  17. FIB and MIP: understanding nanoscale porosity in molecularly imprinted polymers via 3D FIB/SEM tomography.

    Science.gov (United States)

    Neusser, G; Eppler, S; Bowen, J; Allender, C J; Walther, P; Mizaikoff, B; Kranz, C

    2017-10-05

    We present combined focused ion beam/scanning electron beam (FIB/SEM) tomography as innovative method for differentiating and visualizing the distribution and connectivity of pores within molecularly imprinted polymers (MIPs) and non-imprinted control polymers (NIPs). FIB/SEM tomography is used in cell biology for elucidating three-dimensional structures such as organelles, but has not yet been extensively applied for visualizing the heterogeneity of nanoscopic pore networks, interconnectivity, and tortuosity in polymers. To our best knowledge, the present study is the first application of this strategy for analyzing the nanoscale porosity of MIPs. MIPs imprinted for propranolol - and the corresponding NIPs - were investigated establishing FIB/SEM tomography as a viable future strategy complementing conventional isotherm studies. For visualizing and understanding the properties of pore networks in detail, polymer particles were stained with osmium tetroxide (OsO 4 ) vapor, and embedded in epoxy resin. Staining with OsO 4 provides excellent contrast during high-resolution SEM imaging. After optimizing the threshold to discriminate between the stained polymer matrix, and pores filled with epoxy resin, a 3D model of the sampled volume may be established for deriving not only the pore volume and pore surface area, but also to visualize the interconnectivity and tortuosity of the pores within the sampled polymer volume. Detailed studies using different types of cross-linkers and the effect of hydrolysis on the resulting polymer properties have been investigated. In comparison of MIP and NIP, it could be unambiguously shown that the interconnectivity of the visualized pores in MIPs is significantly higher vs. the non-imprinted polymer, and that the pore volume and pore area is 34% and approx. 35% higher within the MIP matrix. This confirms that the templating process not only induces selective binding sites, but indeed also affects the physical properties of such

  18. Description and calibration beamline SEM/Ion Chamber Current Digitizer

    International Nuclear Information System (INIS)

    Schoo, D.

    1994-05-01

    This report discusses the following on beamline SEM/ion chamber current digitizers: Module description; testing and calibration; common setup procedures; summary of fault indications and associated causes; summary of input and output connections; SEM conversion constant table; ion chamber conversion constant table; hexadecimal to decimal conversion table; and schematic diagram

  19. lsnjbhakta@gmail.com A Comparative SEM-EDS Elemental

    African Journals Online (AJOL)

    Michael Horsfall

    effect on food production in terrestrial and aquatic compartment in ... Processing and SEM-EDS analysis of mud: In the laboratory, the ... and for SEM image observation was 15 kV, applying .... by weathering in the Omi acid clay deposit, Japan.

  20. Canticum Novum: música sem palavras e palavras sem som no pensamento de Santo Agostinho

    OpenAIRE

    Mammì, Lorenzo

    2000-01-01

    NO De Magistro, Santo Agostinho coloca a reza e o canto numa posição similar, à margem das funções imediatamente comunicativas da linguagem. A reflexão agostiniana sobre a reza se baseia nos hábitos cristãos da leitura, da oração e da meditação silenciosas. Há sobre o canto, na prática igualmente inovadora do jubilus, melodia sem palavra destinada aos momentos mais intensos e gaudiosos da liturgia. A oração silenciosa e o jubilus são temas recorrentes da literatura patrística, mas Agostinho o...

  1. A RECREATION OPTIMIZATION MODEL BASED ON THE TRAVEL COST METHOD

    OpenAIRE

    Hof, John G.; Loomis, John B.

    1983-01-01

    A recreation allocation model is developed which efficiently selects recreation areas and degree of development from an array of proposed and existing sites. The model does this by maximizing the difference between gross recreation benefits and travel, investment, management, and site-opportunity costs. The model presented uses the Travel Cost Method for estimating recreation benefits within an operations research framework. The model is applied to selection of potential wilderness areas in C...

  2. Continuum methods of physical modeling continuum mechanics, dimensional analysis, turbulence

    CERN Document Server

    Hutter, Kolumban

    2004-01-01

    The book unifies classical continuum mechanics and turbulence modeling, i.e. the same fundamental concepts are used to derive model equations for material behaviour and turbulence closure and complements these with methods of dimensional analysis. The intention is to equip the reader with the ability to understand the complex nonlinear modeling in material behaviour and turbulence closure as well as to derive or invent his own models. Examples are mostly taken from environmental physics and geophysics.

  3. Numerical methods for modeling photonic-crystal VCSELs

    DEFF Research Database (Denmark)

    Dems, Maciej; Chung, Il-Sug; Nyakas, Peter

    2010-01-01

    We show comparison of four different numerical methods for simulating Photonic-Crystal (PC) VCSELs. We present the theoretical basis behind each method and analyze the differences by studying a benchmark VCSEL structure, where the PC structure penetrates all VCSEL layers, the entire top-mirror DBR...... to the effective index method. The simulation results elucidate the strength and weaknesses of the analyzed methods; and outline the limits of applicability of the different models....

  4. A Model-Driven Development Method for Management Information Systems

    Science.gov (United States)

    Mizuno, Tomoki; Matsumoto, Keinosuke; Mori, Naoki

    Traditionally, a Management Information System (MIS) has been developed without using formal methods. By the informal methods, the MIS is developed on its lifecycle without having any models. It causes many problems such as lack of the reliability of system design specifications. In order to overcome these problems, a model theory approach was proposed. The approach is based on an idea that a system can be modeled by automata and set theory. However, it is very difficult to generate automata of the system to be developed right from the start. On the other hand, there is a model-driven development method that can flexibly correspond to changes of business logics or implementing technologies. In the model-driven development, a system is modeled using a modeling language such as UML. This paper proposes a new development method for management information systems applying the model-driven development method to a component of the model theory approach. The experiment has shown that a reduced amount of efforts is more than 30% of all the efforts.

  5. Extension of local front reconstruction method with controlled coalescence model

    Science.gov (United States)

    Rajkotwala, A. H.; Mirsandi, H.; Peters, E. A. J. F.; Baltussen, M. W.; van der Geld, C. W. M.; Kuerten, J. G. M.; Kuipers, J. A. M.

    2018-02-01

    The physics of droplet collisions involves a wide range of length scales. This poses a challenge to accurately simulate such flows with standard fixed grid methods due to their inability to resolve all relevant scales with an affordable number of computational grid cells. A solution is to couple a fixed grid method with subgrid models that account for microscale effects. In this paper, we improved and extended the Local Front Reconstruction Method (LFRM) with a film drainage model of Zang and Law [Phys. Fluids 23, 042102 (2011)]. The new framework is first validated by (near) head-on collision of two equal tetradecane droplets using experimental film drainage times. When the experimental film drainage times are used, the LFRM method is better in predicting the droplet collisions, especially at high velocity in comparison with other fixed grid methods (i.e., the front tracking method and the coupled level set and volume of fluid method). When the film drainage model is invoked, the method shows a good qualitative match with experiments, but a quantitative correspondence of the predicted film drainage time with the experimental drainage time is not obtained indicating that further development of film drainage model is required. However, it can be safely concluded that the LFRM coupled with film drainage models is much better in predicting the collision dynamics than the traditional methods.

  6. Prospective Mathematics Teachers' Opinions about Mathematical Modeling Method and Applicability of This Method

    Science.gov (United States)

    Akgün, Levent

    2015-01-01

    The aim of this study is to identify prospective secondary mathematics teachers' opinions about the mathematical modeling method and the applicability of this method in high schools. The case study design, which is among the qualitative research methods, was used in the study. The study was conducted with six prospective secondary mathematics…

  7. A Comparison of Surface Acoustic Wave Modeling Methods

    Science.gov (United States)

    Wilson, W. c.; Atkinson, G. M.

    2009-01-01

    Surface Acoustic Wave (SAW) technology is low cost, rugged, lightweight, extremely low power and can be used to develop passive wireless sensors. For these reasons, NASA is investigating the use of SAW technology for Integrated Vehicle Health Monitoring (IVHM) of aerospace structures. To facilitate rapid prototyping of passive SAW sensors for aerospace applications, SAW models have been developed. This paper reports on the comparison of three methods of modeling SAWs. The three models are the Impulse Response Method a first order model, and two second order matrix methods; the conventional matrix approach, and a modified matrix approach that is extended to include internal finger reflections. The second order models are based upon matrices that were originally developed for analyzing microwave circuits using transmission line theory. Results from the models are presented with measured data from devices.

  8. Hematite/silver nanoparticle bilayers on mica--AFM, SEM and streaming potential studies.

    Science.gov (United States)

    Morga, Maria; Adamczyk, Zbigniew; Oćwieja, Magdalena; Bielańska, Elżbieta

    2014-06-15

    Bilayers of hematite/silver nanoparticles were obtained in the self-assembly process and thoroughly characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), and in situ streaming potential measurements. The hematite nanoparticles, forming a supporting layer, were 22 nm in diameter, exhibiting an isoelectric point at pH 8.9. The silver nanoparticles, used to obtain an external layer, were 29 nm in diameter, and remained negative within the pH range 3 to 11. In order to investigate the particle deposition, mica sheets were used as a model solid substrate. The coverage of the supporting layer was adjusted by changing the bulk concentration of the hematite suspension and the deposition time. Afterward, silver nanoparticle monolayers of controlled coverage were deposited under the diffusion-controlled transport. The coverage of bilayers was determined by a direct enumeration of deposited particles from SEM micrographs and AFM images. Additionally, the formation of the hematite/silver bilayers was investigated by streaming potential measurements carried out under in situ conditions. The effect of the mica substrate and the coverage of a supporting layer on the zeta potential of bilayers was systematically studied. It was established that for the coverage exceeding 0.20, the zeta potential of bilayers was independent on the substrate and the supporting layer coverage. This behavior was theoretically interpreted in terms of the 3D electrokinetic model. Beside significance for basic sciences, these measurements allowed to develop a robust method of preparing nanoparticle bilayers of controlled properties, having potential applications in catalytic processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Object Oriented Modeling : A method for combining model and software development

    NARCIS (Netherlands)

    Van Lelyveld, W.

    2010-01-01

    When requirements for a new model cannot be met by available modeling software, new software can be developed for a specific model. Methods for the development of both model and software exist, but a method for combined development has not been found. A compatible way of thinking is required to

  10. Method for modeling social care processes for national information exchange.

    Science.gov (United States)

    Miettinen, Aki; Mykkänen, Juha; Laaksonen, Maarit

    2012-01-01

    Finnish social services include 21 service commissions of social welfare including Adoption counselling, Income support, Child welfare, Services for immigrants and Substance abuse care. This paper describes the method used for process modeling in the National project for IT in Social Services in Finland (Tikesos). The process modeling in the project aimed to support common national target state processes from the perspective of national electronic archive, increased interoperability between systems and electronic client documents. The process steps and other aspects of the method are presented. The method was developed, used and refined during the three years of process modeling in the national project.

  11. [A new method of fabricating photoelastic model by rapid prototyping].

    Science.gov (United States)

    Fan, Li; Huang, Qing-feng; Zhang, Fu-qiang; Xia, Yin-pei

    2011-10-01

    To explore a novel method of fabricating the photoelastic model using rapid prototyping technique. A mandible model was made by rapid prototyping with computerized three-dimensional reconstruction, then the photoelastic model with teeth was fabricated by traditional impression duplicating and mould casting. The photoelastic model of mandible with teeth, which was fabricated indirectly by rapid prototyping, was very similar to the prototype in geometry and physical parameters. The model was of high optical sensibility and met the experimental requirements. Photoelastic model of mandible with teeth indirectly fabricated by rapid prototyping meets the photoelastic experimental requirements well.

  12. Stencil method: a Markov model for transport in porous media

    Science.gov (United States)

    Delgoshaie, A. H.; Tchelepi, H.; Jenny, P.

    2016-12-01

    In porous media the transport of fluid is dominated by flow-field heterogeneity resulting from the underlying transmissibility field. Since the transmissibility is highly uncertain, many realizations of a geological model are used to describe the statistics of the transport phenomena in a Monte Carlo framework. One possible way to avoid the high computational cost of physics-based Monte Carlo simulations is to model the velocity field as a Markov process and use Markov Chain Monte Carlo. In previous works multiple Markov models for discrete velocity processes have been proposed. These models can be divided into two general classes of Markov models in time and Markov models in space. Both of these choices have been shown to be effective to some extent. However some studies have suggested that the Markov property cannot be confirmed for a temporal Markov process; Therefore there is not a consensus about the validity and value of Markov models in time. Moreover, previous spacial Markov models have only been used for modeling transport on structured networks and can not be readily applied to model transport in unstructured networks. In this work we propose a novel approach for constructing a Markov model in time (stencil method) for a discrete velocity process. The results form the stencil method are compared to previously proposed spacial Markov models for structured networks. The stencil method is also applied to unstructured networks and can successfully describe the dispersion of particles in this setting. Our conclusion is that both temporal Markov models and spacial Markov models for discrete velocity processes can be valid for a range of model parameters. Moreover, we show that the stencil model can be more efficient in many practical settings and is suited to model dispersion both on structured and unstructured networks.

  13. SmartShadow models and methods for pervasive computing

    CERN Document Server

    Wu, Zhaohui

    2013-01-01

    SmartShadow: Models and Methods for Pervasive Computing offers a new perspective on pervasive computing with SmartShadow, which is designed to model a user as a personality ""shadow"" and to model pervasive computing environments as user-centric dynamic virtual personal spaces. Just like human beings' shadows in the physical world, it follows people wherever they go, providing them with pervasive services. The model, methods, and software infrastructure for SmartShadow are presented and an application for smart cars is also introduced.  The book can serve as a valuable reference work for resea

  14. A numerical method for a transient two-fluid model

    International Nuclear Information System (INIS)

    Le Coq, G.; Libmann, M.

    1978-01-01

    The transient boiling two-phase flow is studied. In nuclear reactors, the driving conditions for the transient boiling are a pump power decay or/and an increase in heating power. The physical model adopted for the two-phase flow is the two fluid model with the assumption that the vapor remains at saturation. The numerical method for solving the thermohydraulics problems is a shooting method, this method is highly implicit. A particular problem exists at the boiling and condensation front. A computer code using this numerical method allow the calculation of a transient boiling initiated by a steady state for a PWR or for a LMFBR

  15. Structural equation modeling in pediatric psychology: overview and review of applications.

    Science.gov (United States)

    Nelson, Timothy D; Aylward, Brandon S; Steele, Ric G

    2008-08-01

    To describe the use of structural equation modeling (SEM) in the Journal of Pediatric Psychology (JPP) and to discuss the usefulness of SEM applications in pediatric psychology research. The use of SEM in JPP between 1997 and 2006 was examined and compared to leading journals in clinical psychology, clinical child psychology, and child development. SEM techniques were used in psychology research, although investigations employing these methods are becoming more prevalent. Despite its infrequent use to date, SEM is a potentially useful tool for advancing pediatric psychology research with a number of advantages over traditional statistical methods.

  16. Physical Model Method for Seismic Study of Concrete Dams

    Directory of Open Access Journals (Sweden)

    Bogdan Roşca

    2008-01-01

    Full Text Available The study of the dynamic behaviour of concrete dams by means of the physical model method is very useful to understand the failure mechanism of these structures to action of the strong earthquakes. Physical model method consists in two main processes. Firstly, a study model must be designed by a physical modeling process using the dynamic modeling theory. The result is a equations system of dimensioning the physical model. After the construction and instrumentation of the scale physical model a structural analysis based on experimental means is performed. The experimental results are gathered and are available to be analysed. Depending on the aim of the research may be designed an elastic or a failure physical model. The requirements for the elastic model construction are easier to accomplish in contrast with those required for a failure model, but the obtained results provide narrow information. In order to study the behaviour of concrete dams to strong seismic action is required the employment of failure physical models able to simulate accurately the possible opening of joint, sliding between concrete blocks and the cracking of concrete. The design relations for both elastic and failure physical models are based on dimensional analysis and consist of similitude relations among the physical quantities involved in the phenomenon. The using of physical models of great or medium dimensions as well as its instrumentation creates great advantages, but this operation involves a large amount of financial, logistic and time resources.

  17. A simple flow-concentration modelling method for integrating water ...

    African Journals Online (AJOL)

    A simple flow-concentration modelling method for integrating water quality and ... flow requirements are assessed for maintenance low flow, drought low flow ... the instream concentrations of chemical constituents that will arise from different ...

  18. Comparison of surrogate models with different methods in ...

    Indian Academy of Sciences (India)

    In this article, polynomial regression (PR), radial basis function artificial neural network (RBFANN), and kriging ..... 10 kriging models with different parameters were also obtained. ..... shapes using stochastic optimization methods and com-.

  19. Method and apparatus for modeling, visualization and analysis of materials

    KAUST Repository

    Aboulhassan, Amal; Hadwiger, Markus

    2016-01-01

    processor and based on the received data, geometric features of the material. The example method further includes extracting, by the processor, particle paths within the material based on the computed geometric features, and geometrically modeling

  20. Advances in Applications of Hierarchical Bayesian Methods with Hydrological Models

    Science.gov (United States)

    Alexander, R. B.; Schwarz, G. E.; Boyer, E. W.

    2017-12-01

    Mechanistic and empirical watershed models are increasingly used to inform water resource decisions. Growing access to historical stream measurements and data from in-situ sensor technologies has increased the need for improved techniques for coupling models with hydrological measurements. Techniques that account for the intrinsic uncertainties of both models and measurements are especially needed. Hierarchical Bayesian methods provide an efficient modeling tool for quantifying model and prediction uncertainties, including those associated with measurements. Hierarchical methods can also be used to explore spatial and temporal variations in model parameters and uncertainties that are informed by hydrological measurements. We used hierarchical Bayesian methods to develop a hybrid (statistical-mechanistic) SPARROW (SPAtially Referenced Regression On Watershed attributes) model of long-term mean annual streamflow across diverse environmental and climatic drainages in 18 U.S. hydrological regions. Our application illustrates the use of a new generation of Bayesian methods that offer more advanced computational efficiencies than the prior generation. Evaluations of the effects of hierarchical (regional) variations in model coefficients and uncertainties on model accuracy indicates improved prediction accuracies (median of 10-50%) but primarily in humid eastern regions, where model uncertainties are one-third of those in arid western regions. Generally moderate regional variability is observed for most hierarchical coefficients. Accounting for measurement and structural uncertainties, using hierarchical state-space techniques, revealed the effects of spatially-heterogeneous, latent hydrological processes in the "localized" drainages between calibration sites; this improved model precision, with only minor changes in regional coefficients. Our study can inform advances in the use of hierarchical methods with hydrological models to improve their integration with stream

  1. Multifunctional Collaborative Modeling and Analysis Methods in Engineering Science

    Science.gov (United States)

    Ransom, Jonathan B.; Broduer, Steve (Technical Monitor)

    2001-01-01

    Engineers are challenged to produce better designs in less time and for less cost. Hence, to investigate novel and revolutionary design concepts, accurate, high-fidelity results must be assimilated rapidly into the design, analysis, and simulation process. This assimilation should consider diverse mathematical modeling and multi-discipline interactions necessitated by concepts exploiting advanced materials and structures. Integrated high-fidelity methods with diverse engineering applications provide the enabling technologies to assimilate these high-fidelity, multi-disciplinary results rapidly at an early stage in the design. These integrated methods must be multifunctional, collaborative, and applicable to the general field of engineering science and mechanics. Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple-method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized. The multifunctional methodology presented provides an effective mechanism by which domains with diverse idealizations are

  2. Nonstandard Finite Difference Method Applied to a Linear Pharmacokinetics Model

    Directory of Open Access Journals (Sweden)

    Oluwaseun Egbelowo

    2017-05-01

    Full Text Available We extend the nonstandard finite difference method of solution to the study of pharmacokinetic–pharmacodynamic models. Pharmacokinetic (PK models are commonly used to predict drug concentrations that drive controlled intravenous (I.V. transfers (or infusion and oral transfers while pharmacokinetic and pharmacodynamic (PD interaction models are used to provide predictions of drug concentrations affecting the response of these clinical drugs. We structure a nonstandard finite difference (NSFD scheme for the relevant system of equations which models this pharamcokinetic process. We compare the results obtained to standard methods. The scheme is dynamically consistent and reliable in replicating complex dynamic properties of the relevant continuous models for varying step sizes. This study provides assistance in understanding the long-term behavior of the drug in the system, and validation of the efficiency of the nonstandard finite difference scheme as the method of choice.

  3. Automated SEM Modal Analysis Applied to the Diogenites

    Science.gov (United States)

    Bowman, L. E.; Spilde, M. N.; Papike, James J.

    1996-01-01

    Analysis of volume proportions of minerals, or modal analysis, is routinely accomplished by point counting on an optical microscope, but the process, particularly on brecciated samples such as the diogenite meteorites, is tedious and prone to error by misidentification of very small fragments, which may make up a significant volume of the sample. Precise volume percentage data can be gathered on a scanning electron microscope (SEM) utilizing digital imaging and an energy dispersive spectrometer (EDS). This form of automated phase analysis reduces error, and at the same time provides more information than could be gathered using simple point counting alone, such as particle morphology statistics and chemical analyses. We have previously studied major, minor, and trace-element chemistry of orthopyroxene from a suite of diogenites. This abstract describes the method applied to determine the modes on this same suite of meteorites and the results of that research. The modal abundances thus determined add additional information on the petrogenesis of the diogenites. In addition, low-abundance phases such as spinels were located for further analysis by this method.

  4. 3D Face modeling using the multi-deformable method.

    Science.gov (United States)

    Hwang, Jinkyu; Yu, Sunjin; Kim, Joongrock; Lee, Sangyoun

    2012-09-25

    In this paper, we focus on the problem of the accuracy performance of 3D face modeling techniques using corresponding features in multiple views, which is quite sensitive to feature extraction errors. To solve the problem, we adopt a statistical model-based 3D face modeling approach in a mirror system consisting of two mirrors and a camera. The overall procedure of our 3D facial modeling method has two primary steps: 3D facial shape estimation using a multiple 3D face deformable model and texture mapping using seamless cloning that is a type of gradient-domain blending. To evaluate our method's performance, we generate 3D faces of 30 individuals and then carry out two tests: accuracy test and robustness test. Our method shows not only highly accurate 3D face shape results when compared with the ground truth, but also robustness to feature extraction errors. Moreover, 3D face rendering results intuitively show that our method is more robust to feature extraction errors than other 3D face modeling methods. An additional contribution of our method is that a wide range of face textures can be acquired by the mirror system. By using this texture map, we generate realistic 3D face for individuals at the end of the paper.

  5. Thermal Efficiency Degradation Diagnosis Method Using Regression Model

    International Nuclear Information System (INIS)

    Jee, Chang Hyun; Heo, Gyun Young; Jang, Seok Won; Lee, In Cheol

    2011-01-01

    This paper proposes an idea for thermal efficiency degradation diagnosis in turbine cycles, which is based on turbine cycle simulation under abnormal conditions and a linear regression model. The correlation between the inputs for representing degradation conditions (normally unmeasured but intrinsic states) and the simulation outputs (normally measured but superficial states) was analyzed with the linear regression model. The regression models can inversely response an associated intrinsic state for a superficial state observed from a power plant. The diagnosis method proposed herein is classified into three processes, 1) simulations for degradation conditions to get measured states (referred as what-if method), 2) development of the linear model correlating intrinsic and superficial states, and 3) determination of an intrinsic state using the superficial states of current plant and the linear regression model (referred as inverse what-if method). The what-if method is to generate the outputs for the inputs including various root causes and/or boundary conditions whereas the inverse what-if method is the process of calculating the inverse matrix with the given superficial states, that is, component degradation modes. The method suggested in this paper was validated using the turbine cycle model for an operating power plant

  6. Dynamic model based on Bayesian method for energy security assessment

    International Nuclear Information System (INIS)

    Augutis, Juozas; Krikštolaitis, Ričardas; Pečiulytė, Sigita; Žutautaitė, Inga

    2015-01-01

    Highlights: • Methodology for dynamic indicator model construction and forecasting of indicators. • Application of dynamic indicator model for energy system development scenarios. • Expert judgement involvement using Bayesian method. - Abstract: The methodology for the dynamic indicator model construction and forecasting of indicators for the assessment of energy security level is presented in this article. An indicator is a special index, which provides numerical values to important factors for the investigated area. In real life, models of different processes take into account various factors that are time-dependent and dependent on each other. Thus, it is advisable to construct a dynamic model in order to describe these dependences. The energy security indicators are used as factors in the dynamic model. Usually, the values of indicators are obtained from statistical data. The developed dynamic model enables to forecast indicators’ variation taking into account changes in system configuration. The energy system development is usually based on a new object construction. Since the parameters of changes of the new system are not exactly known, information about their influences on indicators could not be involved in the model by deterministic methods. Thus, dynamic indicators’ model based on historical data is adjusted by probabilistic model with the influence of new factors on indicators using the Bayesian method

  7. Two updating methods for dissipative models with non symmetric matrices

    International Nuclear Information System (INIS)

    Billet, L.; Moine, P.; Aubry, D.

    1997-01-01

    In this paper the feasibility of the extension of two updating methods to rotating machinery models is considered, the particularity of rotating machinery models is to use non-symmetric stiffness and damping matrices. It is shown that the two methods described here, the inverse Eigen-sensitivity method and the error in constitutive relation method can be adapted to such models given some modification.As far as inverse sensitivity method is concerned, an error function based on the difference between right hand calculated and measured Eigen mode shapes and calculated and measured Eigen values is used. Concerning the error in constitutive relation method, the equation which defines the error has to be modified due to the non definite positiveness of the stiffness matrix. The advantage of this modification is that, in some cases, it is possible to focus the updating process on some specific model parameters. Both methods were validated on a simple test model consisting in a two-bearing and disc rotor system. (author)

  8. A sediment graph model based on SCS-CN method

    Science.gov (United States)

    Singh, P. K.; Bhunya, P. K.; Mishra, S. K.; Chaube, U. C.

    2008-01-01

    SummaryThis paper proposes new conceptual sediment graph models based on coupling of popular and extensively used methods, viz., Nash model based instantaneous unit sediment graph (IUSG), soil conservation service curve number (SCS-CN) method, and Power law. These models vary in their complexity and this paper tests their performance using data of the Nagwan watershed (area = 92.46 km 2) (India). The sensitivity of total sediment yield and peak sediment flow rate computations to model parameterisation is analysed. The exponent of the Power law, β, is more sensitive than other model parameters. The models are found to have substantial potential for computing sediment graphs (temporal sediment flow rate distribution) as well as total sediment yield.

  9. Automated Model Fit Method for Diesel Engine Control Development

    NARCIS (Netherlands)

    Seykens, X.; Willems, F.P.T.; Kuijpers, B.; Rietjens, C.

    2014-01-01

    This paper presents an automated fit for a control-oriented physics-based diesel engine combustion model. This method is based on the combination of a dedicated measurement procedure and structured approach to fit the required combustion model parameters. Only a data set is required that is

  10. Fuzzy Clustering Methods and their Application to Fuzzy Modeling

    DEFF Research Database (Denmark)

    Kroszynski, Uri; Zhou, Jianjun

    1999-01-01

    Fuzzy modeling techniques based upon the analysis of measured input/output data sets result in a set of rules that allow to predict system outputs from given inputs. Fuzzy clustering methods for system modeling and identification result in relatively small rule-bases, allowing fast, yet accurate....... An illustrative synthetic example is analyzed, and prediction accuracy measures are compared between the different variants...

  11. Automated model fit method for diesel engine control development

    NARCIS (Netherlands)

    Seykens, X.L.J.; Willems, F.P.T.; Kuijpers, B.; Rietjens, C.J.H.

    2014-01-01

    This paper presents an automated fit for a control-oriented physics-based diesel engine combustion model. This method is based on the combination of a dedicated measurement procedure and structured approach to fit the required combustion model parameters. Only a data set is required that is

  12. Attitude Research in Science Education: Contemporary Models and Methods.

    Science.gov (United States)

    Crawley, Frank E.; Kobala, Thomas R., Jr.

    1994-01-01

    Presents a summary of models and methods of attitude research which are embedded in the theoretical tenets of social psychology and in the broader framework of constructivism. Focuses on the construction of social reality rather than the construction of physical reality. Models include theory of reasoned action, theory of planned behavior, and…

  13. Approximating methods for intractable probabilistic models: Applications in neuroscience

    DEFF Research Database (Denmark)

    Højen-Sørensen, Pedro

    2002-01-01

    This thesis investigates various methods for carrying out approximate inference in intractable probabilistic models. By capturing the relationships between random variables, the framework of graphical models hints at which sets of random variables pose a problem to the inferential step. The appro...

  14. Hierarchical modelling for the environmental sciences statistical methods and applications

    CERN Document Server

    Clark, James S

    2006-01-01

    New statistical tools are changing the way in which scientists analyze and interpret data and models. Hierarchical Bayes and Markov Chain Monte Carlo methods for analysis provide a consistent framework for inference and prediction where information is heterogeneous and uncertain, processes are complicated, and responses depend on scale. Nowhere are these methods more promising than in the environmental sciences.

  15. Methods for teaching geometric modelling and computer graphics

    Energy Technology Data Exchange (ETDEWEB)

    Rotkov, S.I.; Faitel`son, Yu. Ts.

    1992-05-01

    This paper considers methods for teaching the methods and algorithms of geometric modelling and computer graphics to programmers, designers and users of CAD and computer-aided research systems. There is a bibliography that can be used to prepare lectures and practical classes. 37 refs., 1 tab.

  16. SEM studies of the structure of the gels prepared from untreated and radiation modified potato starch

    International Nuclear Information System (INIS)

    Cieśla, Krystyna; Sartowska, Bożena; Królak, Edward

    2015-01-01

    Potato starch was irradiated with a 60 Co gamma rays using doses of 5, 10, 20 and 30 kGy. Gels containing ca. 9.1% of starch were prepared by heating the starch suspensions in the heating chamber stabilized at 100 °C. Four procedures were applied for preparation of the samples in regard to SEM studies and the ability to observe the radiation effect by SEM was assessed for each method. Differences were observed between the SEM images recorded for the non-irradiated samples prepared using all the methods, and those irradiated. Images of the non-irradiated gels indicate generally a honey-comb structure, while smooth areas but with oriented fractures has appeared after irradiation. Modification of gel structure corresponds to the applied dose. The results were related to the process of gel formation (as observed by means of the hot stage microscope) to decrease in swelling power of the irradiated starch and to decreased viscosity of the resulting gels. It can be concluded that the differences in structural properties of gels shown by SEM result probably due to the better homogenization of the gels formed after radiation induced degradation. - Highlights: • Four procedures of the preservation of starch gels for SEM studies were applied. • The ability to observe the radiation effect by SEM was assessed for each method. • Dose dependent changes in the gel structure were discovered. • It was related to decrease in the swelling power and decreased viscosity of the gels. • A hot-stage microscope was applied in order to follow the gelatinization process

  17. SEM-EBSP能知道些什么

    Institute of Scientific and Technical Information of China (English)

    张唯敏

    2003-01-01

    @@ 1 SEM-EBSP是什么 所谓SEM-EBSP是指采用在扫描电子显微镜(SEM)镜体中的反射电子菊池线衍射的结晶方位分析.被称为菊池图形的衍射图形可因结晶的稍许倾斜而大大地改变其位置,因此,通过解析菊池图形就能正确地知道结晶方位.

  18. Improvement of geometrical measurements from 3D-SEM reconstructions

    DEFF Research Database (Denmark)

    Carli, Lorenzo; De Chiffre, Leonardo; Horsewell, Andy

    2009-01-01

    The quantification of 3D geometry at the nanometric scale is a major metrological challenge. In this work geometrical measurements on cylindrical items obtained with a 3D-SEM were investigated. Two items were measured: a wire gauge having a 0.25 mm nominal diameter and a hypodermic needle having...... that the diameter estimation performed using the 3D-SEM leads to an overestimation of approx. 7% compared to the reference values obtained using a 1-D length measuring machine. Standard deviation of SEM measurements performed on the wire gauge is approx. 1.5 times lower than the one performed on the hypodermic...

  19. Improvement of CD-SEM mark position measurement accuracy

    Science.gov (United States)

    Kasa, Kentaro; Fukuhara, Kazuya

    2014-04-01

    CD-SEM is now attracting attention as a tool that can accurately measure positional error of device patterns. However, the measurement accuracy can get worse due to pattern asymmetry as in the case of image based overlay (IBO) and diffraction based overlay (DBO). For IBO and DBO, a way of correcting the inaccuracy arising from measurement patterns was suggested. For CD-SEM, although a way of correcting CD bias was proposed, it has not been argued how to correct the inaccuracy arising from pattern asymmetry using CD-SEM. In this study we will propose how to quantify and correct the measurement inaccuracy affected by pattern asymmetry.

  20. Using Structural Equation Modelling (SEM) to predict use of ...

    African Journals Online (AJOL)

    mother to child transmission of HIV . It was found to be effective in changing behaviour and studies ... indirectly via intention (willingness) in order to influence the behaviour of coming for VCT. This is because VCT .... similar to those reported in hospital or satellite. (stand-alone) VCT centres, we feel that our findings can also ...

  1. Vortex Tube Modeling Using the System Identification Method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jaeyoung; Jeong, Jiwoong; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of); Im, Seokyeon [Tongmyong Univ., Busan (Korea, Republic of)

    2017-05-15

    In this study, vortex tube system model is developed to predict the temperature of the hot and the cold sides. The vortex tube model is developed based on the system identification method, and the model utilized in this work to design the vortex tube is ARX type (Auto-Regressive with eXtra inputs). The derived polynomial model is validated against experimental data to verify the overall model accuracy. It is also shown that the derived model passes the stability test. It is confirmed that the derived model closely mimics the physical behavior of the vortex tube from both the static and dynamic numerical experiments by changing the angles of the low-temperature side throttle valve, clearly showing temperature separation. These results imply that the system identification based modeling can be a promising approach for the prediction of complex physical systems, including the vortex tube.

  2. Large-signal modeling method for power FETs and diodes

    Energy Technology Data Exchange (ETDEWEB)

    Sun Lu; Wang Jiali; Wang Shan; Li Xuezheng; Shi Hui; Wang Na; Guo Shengping, E-mail: sunlu_1019@126.co [School of Electromechanical Engineering, Xidian University, Xi' an 710071 (China)

    2009-06-01

    Under a large signal drive level, a frequency domain black box model of the nonlinear scattering function is introduced into power FETs and diodes. A time domain measurement system and a calibration method based on a digital oscilloscope are designed to extract the nonlinear scattering function of semiconductor devices. The extracted models can reflect the real electrical performance of semiconductor devices and propose a new large-signal model to the design of microwave semiconductor circuits.

  3. Large-signal modeling method for power FETs and diodes

    International Nuclear Information System (INIS)

    Sun Lu; Wang Jiali; Wang Shan; Li Xuezheng; Shi Hui; Wang Na; Guo Shengping

    2009-01-01

    Under a large signal drive level, a frequency domain black box model of the nonlinear scattering function is introduced into power FETs and diodes. A time domain measurement system and a calibration method based on a digital oscilloscope are designed to extract the nonlinear scattering function of semiconductor devices. The extracted models can reflect the real electrical performance of semiconductor devices and propose a new large-signal model to the design of microwave semiconductor circuits.

  4. A MODELING METHOD OF FLUTTERING LEAVES BASED ON POINT CLOUD

    OpenAIRE

    J. Tang; Y. Wang; Y. Zhao; Y. Zhao; W. Hao; X. Ning; K. Lv; Z. Shi; M. Zhao

    2017-01-01

    Leaves falling gently or fluttering are common phenomenon in nature scenes. The authenticity of leaves falling plays an important part in the dynamic modeling of natural scenes. The leaves falling model has a widely applications in the field of animation and virtual reality. We propose a novel modeling method of fluttering leaves based on point cloud in this paper. According to the shape, the weight of leaves and the wind speed, three basic trajectories of leaves falling are defined, which ar...

  5. Optimization Models and Methods Developed at the Energy Systems Institute

    OpenAIRE

    N.I. Voropai; V.I. Zorkaltsev

    2013-01-01

    The paper presents shortly some optimization models of energy system operation and expansion that have been created at the Energy Systems Institute of the Siberian Branch of the Russian Academy of Sciences. Consideration is given to the optimization models of energy development in Russia, a software package intended for analysis of power system reliability, and model of flow distribution in hydraulic systems. A general idea of the optimization methods developed at the Energy Systems Institute...

  6. Modelling of Airship Flight Mechanics by the Projection Equivalent Method

    OpenAIRE

    Frantisek Jelenciak; Michael Gerke; Ulrich Borgolte

    2015-01-01

    This article describes the projection equivalent method (PEM) as a specific and relatively simple approach for the modelling of aircraft dynamics. By the PEM it is possible to obtain a mathematic al model of the aerodynamic forces and momentums acting on different kinds of aircraft during flight. For the PEM, it is a characteristic of it that - in principle - it provides an acceptable regression model of aerodynamic forces and momentums which exhibits reasonable and plausible behaviour from a...

  7. A discontinuous Galerkin method on kinetic flocking models

    OpenAIRE

    Tan, Changhui

    2014-01-01

    We study kinetic representations of flocking models. They arise from agent-based models for self-organized dynamics, such as Cucker-Smale and Motsch-Tadmor models. We prove flocking behavior for the kinetic descriptions of flocking systems, which indicates a concentration in velocity variable in infinite time. We propose a discontinuous Galerkin method to treat the asymptotic $\\delta$-singularity, and construct high order positive preserving scheme to solve kinetic flocking systems.

  8. Sparse Event Modeling with Hierarchical Bayesian Kernel Methods

    Science.gov (United States)

    2016-01-05

    SECURITY CLASSIFICATION OF: The research objective of this proposal was to develop a predictive Bayesian kernel approach to model count data based on...several predictive variables. Such an approach, which we refer to as the Poisson Bayesian kernel model, is able to model the rate of occurrence of... kernel methods made use of: (i) the Bayesian property of improving predictive accuracy as data are dynamically obtained, and (ii) the kernel function

  9. Modelo de web semántica para universidades

    Directory of Open Access Journals (Sweden)

    Karla Abad

    2015-12-01

    Full Text Available A raíz del estudio de estado actual de micrositios y repositorios en la Universidad Estatal Península de Santa Elena se encontró que su información carecía de semántica óptima y adecuada. Bajo estas circunstancias, se plantea entonces la necesidad de crear un modelo de estructura de web semántica para Universidades, el cual posteriormente fue aplicado a micrositios y repositorio digital de la UPSE, como caso de prueba. Parte de este proyecto incluye la instalación de módulos de software con sus respectivas configuraciones y la utilización de estándares de metadatos como DUBLIN CORE, para la mejora del SEO (optimización en motores de búsqueda; con ello se ha logrado la generación de metadatos estandarizados y la creación de políticas para la subida de información. El uso de metadatos transforma datos simples en estructuras bien organizadas que aportan información y conocimiento para generar resultados en buscadores web. Al culminar la implementación del modelo de web semántica es posible decir que la universidad ha mejorado su presencia y visibilidad en la web a través del indexamiento de información en diferentes motores de búsqueda y posicionamiento en la categorización de universidades y de repositorios de Webometrics (ranking que proporciona clasificación de universidades de todo el mundo.   Abstract After examining the current microsites and repositories situation in University, Peninsula of Santa Elena´s, it was found that information lacked optimal and appropriate semantic. Under these circumstances, there is a need to create a semantic web structure model for Universities, which was subsequently applied to UPSE´s microsites and digital repositories, as a test study case. Part of this project includes the installation of software modules with their respective configurations and the use of metadata standards such as DUBLIN CORE, to improve the SEO (Search Engine Optimization; with these applications, it was

  10. Higher-order triangular spectral element method with optimized cubature points for seismic wavefield modeling

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Youshan, E-mail: ysliu@mail.iggcas.ac.cn [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029 (China); Teng, Jiwen, E-mail: jwteng@mail.iggcas.ac.cn [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029 (China); Xu, Tao, E-mail: xutao@mail.iggcas.ac.cn [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029 (China); CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100101 (China); Badal, José, E-mail: badal@unizar.es [Physics of the Earth, Sciences B, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain)

    2017-05-01

    The mass-lumped method avoids the cost of inverting the mass matrix and simultaneously maintains spatial accuracy by adopting additional interior integration points, known as cubature points. To date, such points are only known analytically in tensor domains, such as quadrilateral or hexahedral elements. Thus, the diagonal-mass-matrix spectral element method (SEM) in non-tensor domains always relies on numerically computed interpolation points or quadrature points. However, only the cubature points for degrees 1 to 6 are known, which is the reason that we have developed a p-norm-based optimization algorithm to obtain higher-order cubature points. In this way, we obtain and tabulate new cubature points with all positive integration weights for degrees 7 to 9. The dispersion analysis illustrates that the dispersion relation determined from the new optimized cubature points is comparable to that of the mass and stiffness matrices obtained by exact integration. Simultaneously, the Lebesgue constant for the new optimized cubature points indicates its surprisingly good interpolation properties. As a result, such points provide both good interpolation properties and integration accuracy. The Courant–Friedrichs–Lewy (CFL) numbers are tabulated for the conventional Fekete-based triangular spectral element (TSEM), the TSEM with exact integration, and the optimized cubature-based TSEM (OTSEM). A complementary study demonstrates the spectral convergence of the OTSEM. A numerical example conducted on a half-space model demonstrates that the OTSEM improves the accuracy by approximately one order of magnitude compared to the conventional Fekete-based TSEM. In particular, the accuracy of the 7th-order OTSEM is even higher than that of the 14th-order Fekete-based TSEM. Furthermore, the OTSEM produces a result that can compete in accuracy with the quadrilateral SEM (QSEM). The high accuracy of the OTSEM is also tested with a non-flat topography model. In terms of computational

  11. Higher-order triangular spectral element method with optimized cubature points for seismic wavefield modeling

    Science.gov (United States)

    Liu, Youshan; Teng, Jiwen; Xu, Tao; Badal, José

    2017-05-01

    The mass-lumped method avoids the cost of inverting the mass matrix and simultaneously maintains spatial accuracy by adopting additional interior integration points, known as cubature points. To date, such points are only known analytically in tensor domains, such as quadrilateral or hexahedral elements. Thus, the diagonal-mass-matrix spectral element method (SEM) in non-tensor domains always relies on numerically computed interpolation points or quadrature points. However, only the cubature points for degrees 1 to 6 are known, which is the reason that we have developed a p-norm-based optimization algorithm to obtain higher-order cubature points. In this way, we obtain and tabulate new cubature points with all positive integration weights for degrees 7 to 9. The dispersion analysis illustrates that the dispersion relation determined from the new optimized cubature points is comparable to that of the mass and stiffness matrices obtained by exact integration. Simultaneously, the Lebesgue constant for the new optimized cubature points indicates its surprisingly good interpolation properties. As a result, such points provide both good interpolation properties and integration accuracy. The Courant-Friedrichs-Lewy (CFL) numbers are tabulated for the conventional Fekete-based triangular spectral element (TSEM), the TSEM with exact integration, and the optimized cubature-based TSEM (OTSEM). A complementary study demonstrates the spectral convergence of the OTSEM. A numerical example conducted on a half-space model demonstrates that the OTSEM improves the accuracy by approximately one order of magnitude compared to the conventional Fekete-based TSEM. In particular, the accuracy of the 7th-order OTSEM is even higher than that of the 14th-order Fekete-based TSEM. Furthermore, the OTSEM produces a result that can compete in accuracy with the quadrilateral SEM (QSEM). The high accuracy of the OTSEM is also tested with a non-flat topography model. In terms of computational

  12. Higher-order triangular spectral element method with optimized cubature points for seismic wavefield modeling

    International Nuclear Information System (INIS)

    Liu, Youshan; Teng, Jiwen; Xu, Tao; Badal, José

    2017-01-01

    The mass-lumped method avoids the cost of inverting the mass matrix and simultaneously maintains spatial accuracy by adopting additional interior integration points, known as cubature points. To date, such points are only known analytically in tensor domains, such as quadrilateral or hexahedral elements. Thus, the diagonal-mass-matrix spectral element method (SEM) in non-tensor domains always relies on numerically computed interpolation points or quadrature points. However, only the cubature points for degrees 1 to 6 are known, which is the reason that we have developed a p-norm-based optimization algorithm to obtain higher-order cubature points. In this way, we obtain and tabulate new cubature points with all positive integration weights for degrees 7 to 9. The dispersion analysis illustrates that the dispersion relation determined from the new optimized cubature points is comparable to that of the mass and stiffness matrices obtained by exact integration. Simultaneously, the Lebesgue constant for the new optimized cubature points indicates its surprisingly good interpolation properties. As a result, such points provide both good interpolation properties and integration accuracy. The Courant–Friedrichs–Lewy (CFL) numbers are tabulated for the conventional Fekete-based triangular spectral element (TSEM), the TSEM with exact integration, and the optimized cubature-based TSEM (OTSEM). A complementary study demonstrates the spectral convergence of the OTSEM. A numerical example conducted on a half-space model demonstrates that the OTSEM improves the accuracy by approximately one order of magnitude compared to the conventional Fekete-based TSEM. In particular, the accuracy of the 7th-order OTSEM is even higher than that of the 14th-order Fekete-based TSEM. Furthermore, the OTSEM produces a result that can compete in accuracy with the quadrilateral SEM (QSEM). The high accuracy of the OTSEM is also tested with a non-flat topography model. In terms of computational

  13. A method for model identification and parameter estimation

    International Nuclear Information System (INIS)

    Bambach, M; Heinkenschloss, M; Herty, M

    2013-01-01

    We propose and analyze a new method for the identification of a parameter-dependent model that best describes a given system. This problem arises, for example, in the mathematical modeling of material behavior where several competing constitutive equations are available to describe a given material. In this case, the models are differential equations that arise from the different constitutive equations, and the unknown parameters are coefficients in the constitutive equations. One has to determine the best-suited constitutive equations for a given material and application from experiments. We assume that the true model is one of the N possible parameter-dependent models. To identify the correct model and the corresponding parameters, we can perform experiments, where for each experiment we prescribe an input to the system and observe a part of the system state. Our approach consists of two stages. In the first stage, for each pair of models we determine the experiment, i.e. system input and observation, that best differentiates between the two models, and measure the distance between the two models. Then we conduct N(N − 1) or, depending on the approach taken, N(N − 1)/2 experiments and use the result of the experiments as well as the previously computed model distances to determine the true model. We provide sufficient conditions on the model distances and measurement errors which guarantee that our approach identifies the correct model. Given the model, we identify the corresponding model parameters in the second stage. The problem in the second stage is a standard parameter estimation problem and we use a method suitable for the given application. We illustrate our approach on three examples, including one where the models are elliptic partial differential equations with different parameterized right-hand sides and an example where we identify the constitutive equation in a problem from computational viscoplasticity. (paper)

  14. Statistical models and methods for reliability and survival analysis

    CERN Document Server

    Couallier, Vincent; Huber-Carol, Catherine; Mesbah, Mounir; Huber -Carol, Catherine; Limnios, Nikolaos; Gerville-Reache, Leo

    2013-01-01

    Statistical Models and Methods for Reliability and Survival Analysis brings together contributions by specialists in statistical theory as they discuss their applications providing up-to-date developments in methods used in survival analysis, statistical goodness of fit, stochastic processes for system reliability, amongst others. Many of these are related to the work of Professor M. Nikulin in statistics over the past 30 years. The authors gather together various contributions with a broad array of techniques and results, divided into three parts - Statistical Models and Methods, Statistical

  15. New airtight transfer box for SEM experiments: Application to lithium and sodium metals observation and analyses.

    Science.gov (United States)

    Stephant, Nicolas; Grissa, Rabeb; Guillou, Fanch; Bretaudeau, Mickaël; Borjon-Piron, Yann; Guillet, Jacques; Moreau, Philippe

    2018-04-18

    The surface of some materials reacts very quickly on contact with air, either because it is oxidized or because it gets humidity from the air. For the sake of original surface observation by scanning electron microscopy (SEM), we conceived an airtight transfer box to keep the samples under vacuum from the place of manufacturing to the SEM chamber. This object is designed to fit in all the models of SEM including those provided with an airlock chamber. The design is voluntarily simplified to allow the manufacturing of the object by a standard mechanical workshop. The transfer box can be easily opened by gravity inside the SEM and allows the preservation of the best vacuum inside, before opening. SEM images and energy dispersive spectroscopy (EDX) analyses of metallic lithium and sodium samples are presented prior and after exposure to the air. X-ray Photoelectron Spectroscopy (XPS) analyses of all samples are also discussed in order to investigate the chemical environments of the detected elements. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Soft tissue digestion of Paradiplozoon vaalense for SEM of sclerites and simultaneous molecular analysis.

    Science.gov (United States)

    Dos Santos, Q M; Avenant-Oldewage, A

    2015-02-01

    Classification of most monogeneans is primarily based on size, shape, and arrangement of haptoral sclerites. These structures are often obscured or misinterpreted when studied using light microscopy, leading to confusion regarding defining characters. Scanning electron microscopy (SEM) has predominantly been used to study haptoral sclerites in smaller monogeneans, focusing on hooks and anchors. In the Diplozoidae, SEM has not been used to study haptoral sclerites. Using new and modified techniques, the sclerites of diplozoids collected in South Africa were successfully studied using SEM. The digestion buffer from a DNA extraction kit was used to digest the surrounding tissue, and Poly-L-lysine-coated and concavity slides were employed to limit the movement and loss of sclerites, with the latter being more user-friendly. In addition to the success of visualizing the sclerites using SEM, the digested tissue from as little as half of the haptor provided viable genetic material for molecular characterization. From the results presented here, the study of the sclerites of larger monogeneans using SEM, including those bearing clamps, is a viable possibility for future research. Also, this method may be beneficial for the study of other, non-haptoral sclerites, such as cirri in other families of monogeneans. During this study, Labeo capensis was noted as a valid host of Paradiplozoon vaalense in a region of the Vaal River where the type host, Labeo umbratus, appears to be absent.

  17. Marginal adaptation of a low-shrinkage silorane-based composite: A SEM-analysis

    DEFF Research Database (Denmark)

    Schmidt, Malene; Bindslev, Preben Hørsted; Poulsen, Sven

    2012-01-01

    shrinkage, has been marketed. Objective. To investigate whether reduced polymerization shrinkage improves the marginal adaptation of composite restorations. Material and methods. A total of 156 scanning electron microscopy (SEM) pictures (78 baseline, 78 follow-up) of the occlusal part of Class II......-casts of the restorations were used for SEM pictures at x 16 magnification. Pictures from baseline and follow-up (398 days, SD 29 days) were randomized and the examiner was blinded to the material and the age of the restoration. Stereologic measurements were used to calculate the length and the width of the marginal...

  18. Modelling viscoacoustic wave propagation with the lattice Boltzmann method.

    Science.gov (United States)

    Xia, Muming; Wang, Shucheng; Zhou, Hui; Shan, Xiaowen; Chen, Hanming; Li, Qingqing; Zhang, Qingchen

    2017-08-31

    In this paper, the lattice Boltzmann method (LBM) is employed to simulate wave propagation in viscous media. LBM is a kind of microscopic method for modelling waves through tracking the evolution states of a large number of discrete particles. By choosing different relaxation times in LBM experiments and using spectrum ratio method, we can reveal the relationship between the quality factor Q and the parameter τ in LBM. A two-dimensional (2D) homogeneous model and a two-layered model are tested in the numerical experiments, and the LBM results are compared against the reference solution of the viscoacoustic equations based on the Kelvin-Voigt model calculated by finite difference method (FDM). The wavefields and amplitude spectra obtained by LBM coincide with those by FDM, which demonstrates the capability of the LBM with one relaxation time. The new scheme is relatively simple and efficient to implement compared with the traditional lattice methods. In addition, through a mass of experiments, we find that the relaxation time of LBM has a quantitative relationship with Q. Such a novel scheme offers an alternative forward modelling kernel for seismic inversion and a new model to describe the underground media.

  19. Sem-observation of developing plant organs using deep-frozen specimens

    NARCIS (Netherlands)

    NN,

    1982-01-01

    The SEM-observation of plant material normally requires dehydrated, dry specimens coated with carbon or metal. Unfortunately, the standard drying methods (including the critical-point-drying-technique) often cause shrinking and deformation of the specimen surface; therefore, SEMstudies on plant

  20. Dimensional verification of high aspect micro structures using FIB-SEM

    DEFF Research Database (Denmark)

    Zhang, Yang; Hansen, Hans Nørgaard

    2013-01-01

    -SEM) assisted by Spip®. The micro features are circular holes 10μm in diameter and 20μm deep, with a 20μm pitch. Various inspection methods were attempted to obtain dimensional information. Due to the dimension, neither optical instrument nor atomic force microscope (AFM) was capable to perform the measurement...

  1. Quantitative Sociodynamics Stochastic Methods and Models of Social Interaction Processes

    CERN Document Server

    Helbing, Dirk

    2010-01-01

    This new edition of Quantitative Sociodynamics presents a general strategy for interdisciplinary model building and its application to a quantitative description of behavioral changes based on social interaction processes. Originally, the crucial methods for the modeling of complex systems (stochastic methods and nonlinear dynamics) were developed in physics and mathematics, but they have very often proven their explanatory power in chemistry, biology, economics and the social sciences as well. Quantitative Sociodynamics provides a unified and comprehensive overview of the different stochastic methods, their interrelations and properties. In addition, it introduces important concepts from nonlinear dynamics (e.g. synergetics, chaos theory). The applicability of these fascinating concepts to social phenomena is carefully discussed. By incorporating decision-theoretical approaches, a fundamental dynamic model is obtained, which opens new perspectives in the social sciences. It includes many established models a...

  2. Quantitative sociodynamics stochastic methods and models of social interaction processes

    CERN Document Server

    Helbing, Dirk

    1995-01-01

    Quantitative Sociodynamics presents a general strategy for interdisciplinary model building and its application to a quantitative description of behavioural changes based on social interaction processes. Originally, the crucial methods for the modeling of complex systems (stochastic methods and nonlinear dynamics) were developed in physics but they have very often proved their explanatory power in chemistry, biology, economics and the social sciences. Quantitative Sociodynamics provides a unified and comprehensive overview of the different stochastic methods, their interrelations and properties. In addition, it introduces the most important concepts from nonlinear dynamics (synergetics, chaos theory). The applicability of these fascinating concepts to social phenomena is carefully discussed. By incorporating decision-theoretical approaches a very fundamental dynamic model is obtained which seems to open new perspectives in the social sciences. It includes many established models as special cases, e.g. the log...

  3. Generalized framework for context-specific metabolic model extraction methods

    Directory of Open Access Journals (Sweden)

    Semidán eRobaina Estévez

    2014-09-01

    Full Text Available Genome-scale metabolic models are increasingly applied to investigate the physiology not only of simple prokaryotes, but also eukaryotes, such as plants, characterized with compartmentalized cells of multiple types. While genome-scale models aim at including the entirety of known metabolic reactions, mounting evidence has indicated that only a subset of these reactions is active in a given context, including: developmental stage, cell type, or environment. As a result, several methods have been proposed to reconstruct context-specific models from existing genome-scale models by integrating various types of high-throughput data. Here we present a mathematical framework that puts all existing methods under one umbrella and provides the means to better understand their functioning, highlight similarities and differences, and to help users in selecting a most suitable method for an application.

  4. Quantitative Methods in Supply Chain Management Models and Algorithms

    CERN Document Server

    Christou, Ioannis T

    2012-01-01

    Quantitative Methods in Supply Chain Management presents some of the most important methods and tools available for modeling and solving problems arising in the context of supply chain management. In the context of this book, “solving problems” usually means designing efficient algorithms for obtaining high-quality solutions. The first chapter is an extensive optimization review covering continuous unconstrained and constrained linear and nonlinear optimization algorithms, as well as dynamic programming and discrete optimization exact methods and heuristics. The second chapter presents time-series forecasting methods together with prediction market techniques for demand forecasting of new products and services. The third chapter details models and algorithms for planning and scheduling with an emphasis on production planning and personnel scheduling. The fourth chapter presents deterministic and stochastic models for inventory control with a detailed analysis on periodic review systems and algorithmic dev...

  5. Dynamic systems models new methods of parameter and state estimation

    CERN Document Server

    2016-01-01

    This monograph is an exposition of a novel method for solving inverse problems, a method of parameter estimation for time series data collected from simulations of real experiments. These time series might be generated by measuring the dynamics of aircraft in flight, by the function of a hidden Markov model used in bioinformatics or speech recognition or when analyzing the dynamics of asset pricing provided by the nonlinear models of financial mathematics. Dynamic Systems Models demonstrates the use of algorithms based on polynomial approximation which have weaker requirements than already-popular iterative methods. Specifically, they do not require a first approximation of a root vector and they allow non-differentiable elements in the vector functions being approximated. The text covers all the points necessary for the understanding and use of polynomial approximation from the mathematical fundamentals, through algorithm development to the application of the method in, for instance, aeroplane flight dynamic...

  6. Method and apparatus for modeling, visualization and analysis of materials

    KAUST Repository

    Aboulhassan, Amal

    2016-08-25

    A method, apparatus, and computer readable medium are provided for modeling of materials and visualization of properties of the materials. An example method includes receiving data describing a set of properties of a material, and computing, by a processor and based on the received data, geometric features of the material. The example method further includes extracting, by the processor, particle paths within the material based on the computed geometric features, and geometrically modeling, by the processor, the material using the geometric features and the extracted particle paths. The example method further includes generating, by the processor and based on the geometric modeling of the material, one or more visualizations regarding the material, and causing display, by a user interface, of the one or more visualizations.

  7. Model based methods and tools for process systems engineering

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    need to be integrated with work-flows and data-flows for specific product-process synthesis-design problems within a computer-aided framework. The framework therefore should be able to manage knowledge-data, models and the associated methods and tools needed by specific synthesis-design work...... of model based methods and tools within a computer aided framework for product-process synthesis-design will be highlighted.......Process systems engineering (PSE) provides means to solve a wide range of problems in a systematic and efficient manner. This presentation will give a perspective on model based methods and tools needed to solve a wide range of problems in product-process synthesis-design. These methods and tools...

  8. Development of an Economical Interfacing Circuit for Upgrading of SEM Data Printing System

    International Nuclear Information System (INIS)

    Punnachaiya, S.; Thong-Aram, D.

    2002-01-01

    The operating conditions of a Scanning Electron Microscope (SEM) i.e., magnification, accelerating voltage, micron mark and film identification labeling, are very important for the accurate interpretation of a micrograph picture. In the old model SEM, the built-in data printing system for film identification can be inputted only the numerical number. This will be made a confusing problems when various operating conditions were applied in routine work. An economical interfacing circuit, therefore, was developed to upgrade the data printing system for capable of alphanumerical labeling. The developed circuit was tested on both data printing systems of JSM-T220 and JSM-T330 (JEOL SEM). It was found that the interfacing function worked properly and easily installed

  9. Kernel Method Based Human Model for Enhancing Interactive Evolutionary Optimization

    Science.gov (United States)

    Zhao, Qiangfu; Liu, Yong

    2015-01-01

    A fitness landscape presents the relationship between individual and its reproductive success in evolutionary computation (EC). However, discrete and approximate landscape in an original search space may not support enough and accurate information for EC search, especially in interactive EC (IEC). The fitness landscape of human subjective evaluation in IEC is very difficult and impossible to model, even with a hypothesis of what its definition might be. In this paper, we propose a method to establish a human model in projected high dimensional search space by kernel classification for enhancing IEC search. Because bivalent logic is a simplest perceptual paradigm, the human model is established by considering this paradigm principle. In feature space, we design a linear classifier as a human model to obtain user preference knowledge, which cannot be supported linearly in original discrete search space. The human model is established by this method for predicting potential perceptual knowledge of human. With the human model, we design an evolution control method to enhance IEC search. From experimental evaluation results with a pseudo-IEC user, our proposed model and method can enhance IEC search significantly. PMID:25879050

  10. Estimation of pump operational state with model-based methods

    International Nuclear Information System (INIS)

    Ahonen, Tero; Tamminen, Jussi; Ahola, Jero; Viholainen, Juha; Aranto, Niina; Kestilae, Juha

    2010-01-01

    Pumps are widely used in industry, and they account for 20% of the industrial electricity consumption. Since the speed variation is often the most energy-efficient method to control the head and flow rate of a centrifugal pump, frequency converters are used with induction motor-driven pumps. Although a frequency converter can estimate the operational state of an induction motor without external measurements, the state of a centrifugal pump or other load machine is not typically considered. The pump is, however, usually controlled on the basis of the required flow rate or output pressure. As the pump operational state can be estimated with a general model having adjustable parameters, external flow rate or pressure measurements are not necessary to determine the pump flow rate or output pressure. Hence, external measurements could be replaced with an adjustable model for the pump that uses estimates of the motor operational state. Besides control purposes, modelling the pump operation can provide useful information for energy auditing and optimization purposes. In this paper, two model-based methods for pump operation estimation are presented. Factors affecting the accuracy of the estimation methods are analyzed. The applicability of the methods is verified by laboratory measurements and tests in two pilot installations. Test results indicate that the estimation methods can be applied to the analysis and control of pump operation. The accuracy of the methods is sufficient for auditing purposes, and the methods can inform the user if the pump is driven inefficiently.

  11. Infrared spectra, Raman laser, XRD, DSC/TGA and SEM ...

    Indian Academy of Sciences (India)

    Administrator

    cussed and the X-ray diffraction, scanning electron microscopy (SEM) and atomic force microscope (AFM) ... acetamide as a simple organic compound at high tempera- ture has less ..... properties of selenium surface, AFM-microscopy tapping.

  12. Novel field emission SEM column with beam deceleration technology

    Energy Technology Data Exchange (ETDEWEB)

    Jiruše, Jaroslav; Havelka, Miloslav; Lopour, Filip

    2014-11-15

    A novel field-emission SEM column has been developed that features Beam Deceleration Mode, high-probe current and ultra-fast scanning. New detection system in the column is introduced to detect true secondary electron signal. The resolution power at low energy was doubled for conventional SEM optics and moderately improved for immersion optics. Application examples at low landing energies include change of contrast, imaging of non-conductive samples and thin layers. - Highlights: • A novel field-emission SEM column has been developed. • Implemented beam deceleration improves the SEM resolution at 1 keV two times. • New column maintains high analytical potential and wide field of view. • Detectors integrated in the column allow gaining true SE and BE signal separately. • Performance of the column is demonstrated on low energy applications.

  13. Role of scanning electron microscope )SEM) in metal failure analysis

    International Nuclear Information System (INIS)

    Shaiful Rizam Shamsudin; Hafizal Yazid; Mohd Harun; Siti Selina Abd Hamid; Nadira Kamarudin; Zaiton Selamat; Mohd Shariff Sattar; Muhamad Jalil

    2005-01-01

    Scanning electron microscope (SEM) is a scientific instrument that uses a beam of highly energetic electrons to examine the surface and phase distribution of specimens on a micro scale through the live imaging of secondary electrons (SE) and back-scattered electrons (BSE) images. One of the main activities of SEM Laboratory at MINT is for failure analysis on metal part and components. The capability of SEM is excellent for determining the root cause of metal failures such as ductility or brittleness, stress corrosion, fatigue and other types of failures. Most of our customers that request for failure analysis are from local petrochemical plants, manufacturers of automotive components, pipeline maintenance personnel and engineers who involved in the development of metal parts and component. This paper intends to discuss some of the technical concepts in failure analysis associated with SEM. (Author)

  14. Novel field emission SEM column with beam deceleration technology

    International Nuclear Information System (INIS)

    Jiruše, Jaroslav; Havelka, Miloslav; Lopour, Filip

    2014-01-01

    A novel field-emission SEM column has been developed that features Beam Deceleration Mode, high-probe current and ultra-fast scanning. New detection system in the column is introduced to detect true secondary electron signal. The resolution power at low energy was doubled for conventional SEM optics and moderately improved for immersion optics. Application examples at low landing energies include change of contrast, imaging of non-conductive samples and thin layers. - Highlights: • A novel field-emission SEM column has been developed. • Implemented beam deceleration improves the SEM resolution at 1 keV two times. • New column maintains high analytical potential and wide field of view. • Detectors integrated in the column allow gaining true SE and BE signal separately. • Performance of the column is demonstrated on low energy applications

  15. Hydrological model uncertainty due to spatial evapotranspiration estimation methods

    Science.gov (United States)

    Yu, Xuan; Lamačová, Anna; Duffy, Christopher; Krám, Pavel; Hruška, Jakub

    2016-05-01

    Evapotranspiration (ET) continues to be a difficult process to estimate in seasonal and long-term water balances in catchment models. Approaches to estimate ET typically use vegetation parameters (e.g., leaf area index [LAI], interception capacity) obtained from field observation, remote sensing data, national or global land cover products, and/or simulated by ecosystem models. In this study we attempt to quantify the uncertainty that spatial evapotranspiration estimation introduces into hydrological simulations when the age of the forest is not precisely known. The Penn State Integrated Hydrologic Model (PIHM) was implemented for the Lysina headwater catchment, located 50°03‧N, 12°40‧E in the western part of the Czech Republic. The spatial forest patterns were digitized from forest age maps made available by the Czech Forest Administration. Two ET methods were implemented in the catchment model: the Biome-BGC forest growth sub-model (1-way coupled to PIHM) and with the fixed-seasonal LAI method. From these two approaches simulation scenarios were developed. We combined the estimated spatial forest age maps and two ET estimation methods to drive PIHM. A set of spatial hydrologic regime and streamflow regime indices were calculated from the modeling results for each method. Intercomparison of the hydrological responses to the spatial vegetation patterns suggested considerable variation in soil moisture and recharge and a small uncertainty in the groundwater table elevation and streamflow. The hydrologic modeling with ET estimated by Biome-BGC generated less uncertainty due to the plant physiology-based method. The implication of this research is that overall hydrologic variability induced by uncertain management practices was reduced by implementing vegetation models in the catchment models.

  16. Applied systems ecology: models, data, and statistical methods

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, L L

    1976-01-01

    In this report, systems ecology is largely equated to mathematical or computer simulation modelling. The need for models in ecology stems from the necessity to have an integrative device for the diversity of ecological data, much of which is observational, rather than experimental, as well as from the present lack of a theoretical structure for ecology. Different objectives in applied studies require specialized methods. The best predictive devices may be regression equations, often non-linear in form, extracted from much more detailed models. A variety of statistical aspects of modelling, including sampling, are discussed. Several aspects of population dynamics and food-chain kinetics are described, and it is suggested that the two presently separated approaches should be combined into a single theoretical framework. It is concluded that future efforts in systems ecology should emphasize actual data and statistical methods, as well as modelling.

  17. Methods improvements incorporated into the SAPHIRE ASP models

    International Nuclear Information System (INIS)

    Sattison, M.B.; Blackman, H.S.; Novack, S.D.

    1995-01-01

    The Office for Analysis and Evaluation of Operational Data (AEOD) has sought the assistance of the Idaho National Engineering Laboratory (INEL) to make some significant enhancements to the SAPHIRE-based Accident Sequence Precursor (ASP) models recently developed by the INEL. The challenge of this project is to provide the features of a full-scale PRA within the framework of the simplified ASP models. Some of these features include: (1) uncertainty analysis addressing the standard PRA uncertainties and the uncertainties unique to the ASP models and methods, (2) incorporation and proper quantification of individual human actions and the interaction among human actions, (3) enhanced treatment of common cause failures, and (4) extension of the ASP models to more closely mimic full-scale PRAs (inclusion of more initiators, explicitly modeling support system failures, etc.). This paper provides an overview of the methods being used to make the above improvements

  18. Improved Cell Culture Method for Growing Contracting Skeletal Muscle Models

    Science.gov (United States)

    Marquette, Michele L.; Sognier, Marguerite A.

    2013-01-01

    An improved method for culturing immature muscle cells (myoblasts) into a mature skeletal muscle overcomes some of the notable limitations of prior culture methods. The development of the method is a major advance in tissue engineering in that, for the first time, a cell-based model spontaneously fuses and differentiates into masses of highly aligned, contracting myotubes. This method enables (1) the construction of improved two-dimensional (monolayer) skeletal muscle test beds; (2) development of contracting three-dimensional tissue models; and (3) improved transplantable tissues for biomedical and regenerative medicine applications. With adaptation, this method also offers potential application for production of other tissue types (i.e., bone and cardiac) from corresponding precursor cells.

  19. Quality control of clinker products by SEM and XRF analysis

    International Nuclear Information System (INIS)

    Ziad Abu Kaddourah; Khairun Azizi

    1996-01-01

    The microstructure and chemical properties of industrial Portland cement clinkers have been examined by SEM and XRF methods to establish the nature of the clinkers and how variations in the clinker characteristics can be used to control the clinker quality. The clinker nodules were found to show differences in the chemical composition and microstructure between the inner and outer parts of the clinker nodules. Microstructure studies of industrial Portland cement clinker have shown that the outer part of the nodules are enriched in silicate more than the inner part. There is better crystallization and larger alite crystal size in the outer part than in the inner part. The alite crystal size varied between 16.2 -46.12 μ m. The clinker chemical composition was found to affect the residual >45 μ m, where a higher belite content causes an increase in the residual >45 μ m in the the cement product and will cause a decrease in the concrete strength of the cement product. The aluminate and ferrite crystals and the microcracks within the alite crystal are clear in some clinker only. The quality of the raw material preparation, burning and cooling stages can be controlled using the microstructure of the clinker product

  20. Evaluation of depth of field in SEM images in terms of the information-passing capacity (IPC) and contrast gradient in SEM image

    International Nuclear Information System (INIS)

    Sato, Mitsugu; Ishitani, Tohru; Watanabe, Shunya; Nakagawa, Mine

    2004-01-01

    The depth of field (DoF) in scanning electron microscope (SEM) images has been determined by estimating the change of image sharpness or resolution near the exact focus position. The image sharpness or resolution along the optical axis is determined by calculating the information-passing capacity (IPC) of an optical system taking into account the effect of pixel size of the image. The change of image sharpness near the exact focus position is determined by measuring the slope gradient of the line profile in SEM images obtained at various focal positions of beam. The change of image sharpness along the optical axis determined by the IPC agrees well with those determined by the slope gradient of line profiles in SEM images when a Gaussian distribution having radius 0.86L p (L p : pixel size in image) at which the intensity has fallen to 1/e of the maximum is applied to the IPC calculation for each pixel intensity. The change of image sharpness near the exact focus position has also been compared with those determined by the CG (Contrast-to-Gradient) method. The CG method slightly underestimates the change of image sharpness compared with those determined by the IPC method

  1. Methods and models in mathematical biology deterministic and stochastic approaches

    CERN Document Server

    Müller, Johannes

    2015-01-01

    This book developed from classes in mathematical biology taught by the authors over several years at the Technische Universität München. The main themes are modeling principles, mathematical principles for the analysis of these models, and model-based analysis of data. The key topics of modern biomathematics are covered: ecology, epidemiology, biochemistry, regulatory networks, neuronal networks, and population genetics. A variety of mathematical methods are introduced, ranging from ordinary and partial differential equations to stochastic graph theory and  branching processes. A special emphasis is placed on the interplay between stochastic and deterministic models.

  2. A Pansharpening Method Based on HCT and Joint Sparse Model

    Directory of Open Access Journals (Sweden)

    XU Ning

    2016-04-01

    Full Text Available A novel fusion method based on the hyperspherical color transformation (HCT and joint sparsity model is proposed for decreasing the spectral distortion of fused image further. In the method, an intensity component and angles of each band of the multispectral image is obtained by HCT firstly, and then the intensity component is fused with the panchromatic image through wavelet transform and joint sparsity model. In the joint sparsity model, the redundant and complement information of the different images can be efficiently extracted and employed to yield the high quality results. Finally, the fused multi spectral image is obtained by inverse transforms of wavelet and HCT on the new lower frequency image and the angle components, respectively. Experimental results on Pleiades-1 and WorldView-2 satellites indicate that the proposed method achieves remarkable results.

  3. FIB-SEM cathodoluminescence tomography: practical and theoretical considerations.

    Science.gov (United States)

    De Winter, D A M; Lebbink, M N; Wiggers De Vries, D F; Post, J A; Drury, M R

    2011-09-01

    Focused ion beam-scanning electron microscope (FIB-SEM) tomography is a powerful application in obtaining three-dimensional (3D) information. The FIB creates a cross section and subsequently removes thin slices. The SEM takes images using secondary or backscattered electrons, or maps every slice using X-rays and/or electron backscatter diffraction patterns. The objective of this study is to assess the possibilities of combining FIB-SEM tomography with cathodoluminescence (CL) imaging. The intensity of CL emission is related to variations in defect or impurity concentrations. A potential problem with FIB-SEM CL tomography is that ion milling may change the defect state of the material and the CL emission. In addition the conventional tilted sample geometry used in FIB-SEM tomography is not compatible with conventional CL detectors. Here we examine the influence of the FIB on CL emission in natural diamond and the feasibility of FIB-SEM CL tomography. A systematic investigation establishes that the ion beam influences CL emission of diamond, with a dependency on both the ion beam and electron beam acceleration voltage. CL emission in natural diamond is enhanced particularly at low ion beam and electron beam voltages. This enhancement of the CL emission can be partly explained by an increase in surface defects induced by ion milling. CL emission enhancement could be used to improve the CL image quality. To conduct FIB-SEM CL tomography, a recently developed novel specimen geometry is adopted to enable sequential ion milling and CL imaging on an untilted sample. We show that CL imaging can be manually combined with FIB-SEM tomography with a modified protocol for 3D microstructure reconstruction. In principle, automated FIB-SEM CL tomography should be feasible, provided that dedicated CL detectors are developed that allow subsequent milling and CL imaging without manual intervention, as the current CL detector needs to be manually retracted before a slice can be milled

  4. Continuum-Kinetic Models and Numerical Methods for Multiphase Applications

    Science.gov (United States)

    Nault, Isaac Michael

    This thesis presents a continuum-kinetic approach for modeling general problems in multiphase solid mechanics. In this context, a continuum model refers to any model, typically on the macro-scale, in which continuous state variables are used to capture the most important physics: conservation of mass, momentum, and energy. A kinetic model refers to any model, typically on the meso-scale, which captures the statistical motion and evolution of microscopic entitites. Multiphase phenomena usually involve non-negligible micro or meso-scopic effects at the interfaces between phases. The approach developed in the thesis attempts to combine the computational performance benefits of a continuum model with the physical accuracy of a kinetic model when applied to a multiphase problem. The approach is applied to modeling a single particle impact in Cold Spray, an engineering process that intimately involves the interaction of crystal grains with high-magnitude elastic waves. Such a situation could be classified a multiphase application due to the discrete nature of grains on the spatial scale of the problem. For this application, a hyper elasto-plastic model is solved by a finite volume method with approximate Riemann solver. The results of this model are compared for two types of plastic closure: a phenomenological macro-scale constitutive law, and a physics-based meso-scale Crystal Plasticity model.

  5. Statistical learning modeling method for space debris photometric measurement

    Science.gov (United States)

    Sun, Wenjing; Sun, Jinqiu; Zhang, Yanning; Li, Haisen

    2016-03-01

    Photometric measurement is an important way to identify the space debris, but the present methods of photometric measurement have many constraints on star image and need complex image processing. Aiming at the problems, a statistical learning modeling method for space debris photometric measurement is proposed based on the global consistency of the star image, and the statistical information of star images is used to eliminate the measurement noises. First, the known stars on the star image are divided into training stars and testing stars. Then, the training stars are selected as the least squares fitting parameters to construct the photometric measurement model, and the testing stars are used to calculate the measurement accuracy of the photometric measurement model. Experimental results show that, the accuracy of the proposed photometric measurement model is about 0.1 magnitudes.

  6. Efficient model learning methods for actor-critic control.

    Science.gov (United States)

    Grondman, Ivo; Vaandrager, Maarten; Buşoniu, Lucian; Babuska, Robert; Schuitema, Erik

    2012-06-01

    We propose two new actor-critic algorithms for reinforcement learning. Both algorithms use local linear regression (LLR) to learn approximations of the functions involved. A crucial feature of the algorithms is that they also learn a process model, and this, in combination with LLR, provides an efficient policy update for faster learning. The first algorithm uses a novel model-based update rule for the actor parameters. The second algorithm does not use an explicit actor but learns a reference model which represents a desired behavior, from which desired control actions can be calculated using the inverse of the learned process model. The two novel methods and a standard actor-critic algorithm are applied to the pendulum swing-up problem, in which the novel methods achieve faster learning than the standard algorithm.

  7. Methods of mathematical modelling continuous systems and differential equations

    CERN Document Server

    Witelski, Thomas

    2015-01-01

    This book presents mathematical modelling and the integrated process of formulating sets of equations to describe real-world problems. It describes methods for obtaining solutions of challenging differential equations stemming from problems in areas such as chemical reactions, population dynamics, mechanical systems, and fluid mechanics. Chapters 1 to 4 cover essential topics in ordinary differential equations, transport equations and the calculus of variations that are important for formulating models. Chapters 5 to 11 then develop more advanced techniques including similarity solutions, matched asymptotic expansions, multiple scale analysis, long-wave models, and fast/slow dynamical systems. Methods of Mathematical Modelling will be useful for advanced undergraduate or beginning graduate students in applied mathematics, engineering and other applied sciences.

  8. Curve fitting methods for solar radiation data modeling

    Energy Technology Data Exchange (ETDEWEB)

    Karim, Samsul Ariffin Abdul, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my; Singh, Balbir Singh Mahinder, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my [Department of Fundamental and Applied Sciences, Faculty of Sciences and Information Technology, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan (Malaysia)

    2014-10-24

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R{sup 2}. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  9. Curve fitting methods for solar radiation data modeling

    Science.gov (United States)

    Karim, Samsul Ariffin Abdul; Singh, Balbir Singh Mahinder

    2014-10-01

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R2. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  10. Curve fitting methods for solar radiation data modeling

    International Nuclear Information System (INIS)

    Karim, Samsul Ariffin Abdul; Singh, Balbir Singh Mahinder

    2014-01-01

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R 2 . The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods

  11. Discrete gradient methods for solving variational image regularisation models

    International Nuclear Information System (INIS)

    Grimm, V; McLachlan, Robert I; McLaren, David I; Quispel, G R W; Schönlieb, C-B

    2017-01-01

    Discrete gradient methods are well-known methods of geometric numerical integration, which preserve the dissipation of gradient systems. In this paper we show that this property of discrete gradient methods can be interesting in the context of variational models for image processing, that is where the processed image is computed as a minimiser of an energy functional. Numerical schemes for computing minimisers of such energies are desired to inherit the dissipative property of the gradient system associated to the energy and consequently guarantee a monotonic decrease of the energy along iterations, avoiding situations in which more computational work might lead to less optimal solutions. Under appropriate smoothness assumptions on the energy functional we prove that discrete gradient methods guarantee a monotonic decrease of the energy towards stationary states, and we promote their use in image processing by exhibiting experiments with convex and non-convex variational models for image deblurring, denoising, and inpainting. (paper)

  12. A meshless method for modeling convective heat transfer

    Energy Technology Data Exchange (ETDEWEB)

    Carrington, David B [Los Alamos National Laboratory

    2010-01-01

    A meshless method is used in a projection-based approach to solve the primitive equations for fluid flow with heat transfer. The method is easy to implement in a MATLAB format. Radial basis functions are used to solve two benchmark test cases: natural convection in a square enclosure and flow with forced convection over a backward facing step. The results are compared with two popular and widely used commercial codes: COMSOL, a finite element model, and FLUENT, a finite volume-based model.

  13. High resolution SEM imaging of gold nanoparticles in cells and tissues.

    Science.gov (United States)

    Goldstein, A; Soroka, Y; Frušić-Zlotkin, M; Popov, I; Kohen, R

    2014-12-01

    The growing demand of gold nanoparticles in medical applications increases the need for simple and efficient characterization methods of the interaction between the nanoparticles and biological systems. Due to its nanometre resolution, modern scanning electron microscopy (SEM) offers straightforward visualization of metallic nanoparticles down to a few nanometre size, almost without any special preparation step. However, visualization of biological materials in SEM requires complicated preparation procedure, which is typically finished by metal coating needed to decrease charging artefacts and quick radiation damage of biomaterials in the course of SEM imaging. The finest conductive metal coating available is usually composed of a few nanometre size clusters, which are almost identical to the metal nanoparticles employed in medical applications. Therefore, SEM monitoring of metal nanoparticles within cells and tissues is incompatible with the conventional preparation methods. In this work, we show that charging artefacts related to non-conductive biological specimen can be successfully eliminated by placing the uncoated biological sample on a conductive substrate. By growing the cells on glass pre-coated with a chromium layer, we were able to observe the uptake of 10 nm gold nanoparticles inside uncoated and unstained macrophages and keratinocytes cells. Imaging in back scattered electrons allowed observation of gold nanoparticles located inside the cells, while imaging in secondary electron gave information on gold nanoparticles located on the surface of the cells. By mounting a skin cross-section on an improved conductive holder, consisting of a silicon substrate coated with copper, we were able to observe penetration of gold nanoparticles of only 5 nm size through the skin barrier in an uncoated skin tissue. The described method offers a convenient modification in preparation procedure for biological samples to be analyzed in SEM. The method provides high

  14. Deterministic operations research models and methods in linear optimization

    CERN Document Server

    Rader, David J

    2013-01-01

    Uniquely blends mathematical theory and algorithm design for understanding and modeling real-world problems Optimization modeling and algorithms are key components to problem-solving across various fields of research, from operations research and mathematics to computer science and engineering. Addressing the importance of the algorithm design process. Deterministic Operations Research focuses on the design of solution methods for both continuous and discrete linear optimization problems. The result is a clear-cut resource for understanding three cornerstones of deterministic operations resear

  15. Evaluation process radiological in ternopil region method of box models

    Directory of Open Access Journals (Sweden)

    І.В. Матвєєва

    2006-02-01

    Full Text Available  Results of radionuclides Sr-90 flows analyses in the ecosystem of Kotsubinchiky village of Ternopolskaya oblast were analyzed. The block-scheme of ecosystem and its mathematical model using the box models method were made. It allowed us to evaluate the ways of dose’s loadings formation of internal irradiation for miscellaneous population groups – working people, retirees, children, and also to prognose the dynamic of these loadings during the years after the Chernobyl accident.

  16. The Langevin method and Hubbard-like models

    International Nuclear Information System (INIS)

    Gross, M.; Hamber, H.

    1989-01-01

    The authors reexamine the difficulties associated with application of the Langevin method to numerical simulation of models with non-positive definite statistical weights, including the Hubbard model. They show how to avoid the violent crossing of the zeroes of the weight and how to move those nodes away from the real axis. However, it still appears necessary to keep track of the sign (or phase) of the weight

  17. Regression modeling methods, theory, and computation with SAS

    CERN Document Server

    Panik, Michael

    2009-01-01

    Regression Modeling: Methods, Theory, and Computation with SAS provides an introduction to a diverse assortment of regression techniques using SAS to solve a wide variety of regression problems. The author fully documents the SAS programs and thoroughly explains the output produced by the programs.The text presents the popular ordinary least squares (OLS) approach before introducing many alternative regression methods. It covers nonparametric regression, logistic regression (including Poisson regression), Bayesian regression, robust regression, fuzzy regression, random coefficients regression,

  18. An alternative method for centrifugal compressor loading factor modelling

    Science.gov (United States)

    Galerkin, Y.; Drozdov, A.; Rekstin, A.; Soldatova, K.

    2017-08-01

    The loading factor at design point is calculated by one or other empirical formula in classical design methods. Performance modelling as a whole is out of consideration. Test data of compressor stages demonstrates that loading factor versus flow coefficient at the impeller exit has a linear character independent of compressibility. Known Universal Modelling Method exploits this fact. Two points define the function - loading factor at design point and at zero flow rate. The proper formulae include empirical coefficients. A good modelling result is possible if the choice of coefficients is based on experience and close analogs. Earlier Y. Galerkin and K. Soldatova had proposed to define loading factor performance by the angle of its inclination to the ordinate axis and by the loading factor at zero flow rate. Simple and definite equations with four geometry parameters were proposed for loading factor performance calculated for inviscid flow. The authors of this publication have studied the test performance of thirteen stages of different types. The equations are proposed with universal empirical coefficients. The calculation error lies in the range of plus to minus 1,5%. The alternative model of a loading factor performance modelling is included in new versions of the Universal Modelling Method.

  19. Analytical models approximating individual processes: a validation method.

    Science.gov (United States)

    Favier, C; Degallier, N; Menkès, C E

    2010-12-01

    Upscaling population models from fine to coarse resolutions, in space, time and/or level of description, allows the derivation of fast and tractable models based on a thorough knowledge of individual processes. The validity of such approximations is generally tested only on a limited range of parameter sets. A more general validation test, over a range of parameters, is proposed; this would estimate the error induced by the approximation, using the original model's stochastic variability as a reference. This method is illustrated by three examples taken from the field of epidemics transmitted by vectors that bite in a temporally cyclical pattern, that illustrate the use of the method: to estimate if an approximation over- or under-fits the original model; to invalidate an approximation; to rank possible approximations for their qualities. As a result, the application of the validation method to this field emphasizes the need to account for the vectors' biology in epidemic prediction models and to validate these against finer scale models. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Research on Multi - Person Parallel Modeling Method Based on Integrated Model Persistent Storage

    Science.gov (United States)

    Qu, MingCheng; Wu, XiangHu; Tao, YongChao; Liu, Ying

    2018-03-01

    This paper mainly studies the multi-person parallel modeling method based on the integrated model persistence storage. The integrated model refers to a set of MDDT modeling graphics system, which can carry out multi-angle, multi-level and multi-stage description of aerospace general embedded software. Persistent storage refers to converting the data model in memory into a storage model and converting the storage model into a data model in memory, where the data model refers to the object model and the storage model is a binary stream. And multi-person parallel modeling refers to the need for multi-person collaboration, the role of separation, and even real-time remote synchronization modeling.

  1. Annular dispersed flow analysis model by Lagrangian method and liquid film cell method

    International Nuclear Information System (INIS)

    Matsuura, K.; Kuchinishi, M.; Kataoka, I.; Serizawa, A.

    2003-01-01

    A new annular dispersed flow analysis model was developed. In this model, both droplet behavior and liquid film behavior were simultaneously analyzed. Droplet behavior in turbulent flow was analyzed by the Lagrangian method with refined stochastic model. On the other hand, liquid film behavior was simulated by the boundary condition of moving rough wall and liquid film cell model, which was used to estimate liquid film flow rate. The height of moving rough wall was estimated by disturbance wave height correlation. In each liquid film cell, liquid film flow rate was calculated by considering droplet deposition and entrainment flow rate. Droplet deposition flow rate was calculated by Lagrangian method and entrainment flow rate was calculated by entrainment correlation. For the verification of moving rough wall model, turbulent flow analysis results under the annular flow condition were compared with the experimental data. Agreement between analysis results and experimental results were fairly good. Furthermore annular dispersed flow experiments were analyzed, in order to verify droplet behavior model and the liquid film cell model. The experimental results of radial distribution of droplet mass flux were compared with analysis results. The agreement was good under low liquid flow rate condition and poor under high liquid flow rate condition. But by modifying entrainment rate correlation, the agreement become good even under high liquid flow rate. This means that basic analysis method of droplet and liquid film behavior was right. In future work, verification calculation should be carried out under different experimental condition and entrainment ratio correlation also should be corrected

  2. Multilevel method for modeling large-scale networks.

    Energy Technology Data Exchange (ETDEWEB)

    Safro, I. M. (Mathematics and Computer Science)

    2012-02-24

    Understanding the behavior of real complex networks is of great theoretical and practical significance. It includes developing accurate artificial models whose topological properties are similar to the real networks, generating the artificial networks at different scales under special conditions, investigating a network dynamics, reconstructing missing data, predicting network response, detecting anomalies and other tasks. Network generation, reconstruction, and prediction of its future topology are central issues of this field. In this project, we address the questions related to the understanding of the network modeling, investigating its structure and properties, and generating artificial networks. Most of the modern network generation methods are based either on various random graph models (reinforced by a set of properties such as power law distribution of node degrees, graph diameter, and number of triangles) or on the principle of replicating an existing model with elements of randomization such as R-MAT generator and Kronecker product modeling. Hierarchical models operate at different levels of network hierarchy but with the same finest elements of the network. However, in many cases the methods that include randomization and replication elements on the finest relationships between network nodes and modeling that addresses the problem of preserving a set of simplified properties do not fit accurately enough the real networks. Among the unsatisfactory features are numerically inadequate results, non-stability of algorithms on real (artificial) data, that have been tested on artificial (real) data, and incorrect behavior at different scales. One reason is that randomization and replication of existing structures can create conflicts between fine and coarse scales of the real network geometry. Moreover, the randomization and satisfying of some attribute at the same time can abolish those topological attributes that have been undefined or hidden from

  3. Methods and models used in comparative risk studies

    International Nuclear Information System (INIS)

    Devooght, J.

    1983-01-01

    Comparative risk studies make use of a large number of methods and models based upon a set of assumptions incompletely formulated or of value judgements. Owing to the multidimensionality of risks and benefits, the economic and social context may notably influence the final result. Five classes of models are briefly reviewed: accounting of fluxes of effluents, radiation and energy; transport models and health effects; systems reliability and bayesian analysis; economic analysis of reliability and cost-risk-benefit analysis; decision theory in presence of uncertainty and multiple objectives. Purpose and prospect of comparative studies are assessed in view of probable diminishing returns for large generic comparisons [fr

  4. Toric Lego: A method for modular model building

    CERN Document Server

    Balasubramanian, Vijay; García-Etxebarria, Iñaki

    2010-01-01

    Within the context of local type IIB models arising from branes at toric Calabi-Yau singularities, we present a systematic way of joining any number of desired sectors into a consistent theory. The different sectors interact via massive messengers with masses controlled by tunable parameters. We apply this method to a toy model of the minimal supersymmetric standard model (MSSM) interacting via gauge mediation with a metastable supersymmetry breaking sector and an interacting dark matter sector. We discuss how a mirror procedure can be applied in the type IIA case, allowing us to join certain intersecting brane configurations through massive mediators.

  5. Modelling across bioreactor scales: methods, challenges and limitations

    DEFF Research Database (Denmark)

    Gernaey, Krist

    that it is challenging and expensive to acquire experimental data of good quality that can be used for characterizing gradients occurring inside a large industrial scale bioreactor. But which model building methods are available? And how can one ensure that the parameters in such a model are properly estimated? And what......Scale-up and scale-down of bioreactors are very important in industrial biotechnology, especially with the currently available knowledge on the occurrence of gradients in industrial-scale bioreactors. Moreover, it becomes increasingly appealing to model such industrial scale systems, considering...

  6. Novel extrapolation method in the Monte Carlo shell model

    International Nuclear Information System (INIS)

    Shimizu, Noritaka; Abe, Takashi; Utsuno, Yutaka; Mizusaki, Takahiro; Otsuka, Takaharu; Honma, Michio

    2010-01-01

    We propose an extrapolation method utilizing energy variance in the Monte Carlo shell model to estimate the energy eigenvalue and observables accurately. We derive a formula for the energy variance with deformed Slater determinants, which enables us to calculate the energy variance efficiently. The feasibility of the method is demonstrated for the full pf-shell calculation of 56 Ni, and the applicability of the method to a system beyond the current limit of exact diagonalization is shown for the pf+g 9/2 -shell calculation of 64 Ge.

  7. Moments Method for Shell-Model Level Density

    International Nuclear Information System (INIS)

    Zelevinsky, V; Horoi, M; Sen'kov, R A

    2016-01-01

    The modern form of the Moments Method applied to the calculation of the nuclear shell-model level density is explained and examples of the method at work are given. The calculated level density practically exactly coincides with the result of full diagonalization when the latter is feasible. The method provides the pure level density for given spin and parity with spurious center-of-mass excitations subtracted. The presence and interplay of all correlations leads to the results different from those obtained by the mean-field combinatorics. (paper)

  8. Modeling of the inhomogeneity of grain refinement during combined metal forming process by finite element and cellular automata methods

    Energy Technology Data Exchange (ETDEWEB)

    Majta, Janusz; Madej, Łukasz; Svyetlichnyy, Dmytro S.; Perzyński, Konrad; Kwiecień, Marcin, E-mail: mkwiecie@agh.edu.pl; Muszka, Krzysztof

    2016-08-01

    The potential of discrete cellular automata technique to predict the grain refinement in wires produced using combined metal forming process is presented and discussed within the paper. The developed combined metal forming process can be treated as one of the Severe Plastic Deformation (SPD) techniques that consists of three different modes of deformation: asymmetric drawing with bending, namely accumulated angular drawing (AAD), wire drawing (WD) and wire flattening (WF). To accurately replicate complex stress state both at macro and micro scales during subsequent deformations two stage modeling approach was used. First, the Finite Element Method (FEM), implemented in commercial ABAQUS software, was applied to simulate entire combined forming process at the macro scale level. Then, based on FEM results, the Cellular Automata (CA) method was applied for simulation of grain refinement at the microstructure level. Data transferred between FEM and CA methods included set of files with strain tensor components obtained from selected integration points in the macro scale model. As a result of CA simulation, detailed information on microstructure evolution during severe plastic deformation conditions was obtained, namely: changes of shape and sizes of modeled representative volume with imposed microstructure, changes of the number of grains, subgrains and dislocation cells, development of grain boundaries angle distribution as well as changes in the pole figures. To evaluate CA model predictive capabilities, results of computer simulation were compared with scanning electron microscopy and electron back scattered diffraction images (SEM/EBSD) studies of samples after AAD+WD+WF process.

  9. Surface topography characterization using 3D stereoscopic reconstruction of SEM images

    Science.gov (United States)

    Vedantha Krishna, Amogh; Flys, Olena; Reddy, Vijeth V.; Rosén, B. G.

    2018-06-01

    A major drawback of the optical microscope is its limitation to resolve finer details. Many microscopes have been developed to overcome the limitations set by the diffraction of visible light. The scanning electron microscope (SEM) is one such alternative: it uses electrons for imaging, which have much smaller wavelength than photons. As a result high magnification with superior image resolution can be achieved. However, SEM generates 2D images which provide limited data for surface measurements and analysis. Often many research areas require the knowledge of 3D structures as they contribute to a comprehensive understanding of microstructure by allowing effective measurements and qualitative visualization of the samples under study. For this reason, stereo photogrammetry technique is employed to convert SEM images into 3D measurable data. This paper aims to utilize a stereoscopic reconstruction technique as a reliable method for characterization of surface topography. Reconstructed results from SEM images are compared with coherence scanning interferometer (CSI) results obtained by measuring a roughness reference standard sample. This paper presents a method to select the most robust/consistent surface texture parameters that are insensitive to the uncertainties involved in the reconstruction technique itself. Results from the two-stereoscopic reconstruction algorithms are also documented in this paper.

  10. Methods improvements incorporated into the SAPHIRE ASP models

    International Nuclear Information System (INIS)

    Sattison, M.B.; Blackman, H.S.; Novack, S.D.; Smith, C.L.; Rasmuson, D.M.

    1994-01-01

    The Office for Analysis and Evaluation of Operational Data (AEOD) has sought the assistance of the Idaho National Engineering Laboratory (INEL) to make some significant enhancements to the SAPHIRE-based Accident Sequence Precursor (ASP) models recently developed by the INEL. The challenge of this project is to provide the features of a full-scale PRA within the framework of the simplified ASP models. Some of these features include: (1) uncertainty analysis addressing the standard PRA uncertainties and the uncertainties unique to the ASP models and methodology, (2) incorporation and proper quantification of individual human actions and the interaction among human actions, (3) enhanced treatment of common cause failures, and (4) extension of the ASP models to more closely mimic full-scale PRAs (inclusion of more initiators, explicitly modeling support system failures, etc.). This paper provides an overview of the methods being used to make the above improvements

  11. Optimisation-Based Solution Methods for Set Partitioning Models

    DEFF Research Database (Denmark)

    Rasmussen, Matias Sevel

    The scheduling of crew, i.e. the construction of work schedules for crew members, is often not a trivial task, but a complex puzzle. The task is complicated by rules, restrictions, and preferences. Therefore, manual solutions as well as solutions from standard software packages are not always su......_cient with respect to solution quality and solution time. Enhancement of the overall solution quality as well as the solution time can be of vital importance to many organisations. The _elds of operations research and mathematical optimisation deal with mathematical modelling of di_cult scheduling problems (among...... other topics). The _elds also deal with the development of sophisticated solution methods for these mathematical models. This thesis describes the set partitioning model which has been widely used for modelling crew scheduling problems. Integer properties for the set partitioning model are shown...

  12. A methodology for extending domain coverage in SemRep.

    Science.gov (United States)

    Rosemblat, Graciela; Shin, Dongwook; Kilicoglu, Halil; Sneiderman, Charles; Rindflesch, Thomas C

    2013-12-01

    We describe a domain-independent methodology to extend SemRep coverage beyond the biomedical domain. SemRep, a natural language processing application originally designed for biomedical texts, uses the knowledge sources provided by the Unified Medical Language System (UMLS©). Ontological and terminological extensions to the system are needed in order to support other areas of knowledge. We extended SemRep's application by developing a semantic representation of a previously unsupported domain. This was achieved by adapting well-known ontology engineering phases and integrating them with the UMLS knowledge sources on which SemRep crucially depends. While the process to extend SemRep coverage has been successfully applied in earlier projects, this paper presents in detail the step-wise approach we followed and the mechanisms implemented. A case study in the field of medical informatics illustrates how the ontology engineering phases have been adapted for optimal integration with the UMLS. We provide qualitative and quantitative results, which indicate the validity and usefulness of our methodology. Published by Elsevier Inc.

  13. Modelling of Granular Materials Using the Discrete Element Method

    DEFF Research Database (Denmark)

    Ullidtz, Per

    1997-01-01

    With the Discrete Element Method it is possible to model materials that consists of individual particles where a particle may role or slide on other particles. This is interesting because most of the deformation in granular materials is due to rolling or sliding rather that compression of the gra...

  14. Moderation instead of modelling: some arguments against formal engineering methods

    NARCIS (Netherlands)

    Rauterberg, G.W.M.; Sikorski, M.; Rauterberg, G.W.M.

    1998-01-01

    The more formal the used engineering techniques are, the less non-technical facts can be captured. Several business process reengineering and software development projects fail, because the project management concentrates to much on formal methods and modelling approaches. A successful change of

  15. The research methods and model of protein turnover in animal

    International Nuclear Information System (INIS)

    Wu Xilin; Yang Feng

    2002-01-01

    The author discussed the concept and research methods of protein turnover in animal body. The existing problems and the research results of animal protein turnover in recent years were presented. Meanwhile, the measures to improve the models of animal protein turnover were analyzed

  16. Methods and models for the construction of weakly parallel tests

    NARCIS (Netherlands)

    Adema, J.J.; Adema, Jos J.

    1992-01-01

    Several methods are proposed for the construction of weakly parallel tests [i.e., tests with the same test information function (TIF)]. A mathematical programming model that constructs tests containing a prespecified TIF and a heuristic that assigns items to tests with information functions that are

  17. Ethnographic Decision Tree Modeling: A Research Method for Counseling Psychology.

    Science.gov (United States)

    Beck, Kirk A.

    2005-01-01

    This article describes ethnographic decision tree modeling (EDTM; C. H. Gladwin, 1989) as a mixed method design appropriate for counseling psychology research. EDTM is introduced and located within a postpositivist research paradigm. Decision theory that informs EDTM is reviewed, and the 2 phases of EDTM are highlighted. The 1st phase, model…

  18. Heat bath method for the twisted Eguchi-Kawai model

    International Nuclear Information System (INIS)

    Fabricius, K.; Haan, O.

    1984-01-01

    We reformulate the twisted Eguchi-Kawaii model in a way that allows us to use the heat bath method for the updating procedure of the link matrices. This new formulation is more efficient by a factor of 2.5 in computer time and of 2.3 in memory need. (orig.)

  19. Heat bath method for the twisted Eguchi-Kawai model

    Energy Technology Data Exchange (ETDEWEB)

    Fabricius, K.; Haan, O.

    1984-08-16

    We reformulate the twisted Eguchi-Kawaii model in a way that allows us to use the heat bath method for the updating procedure of the link matrices. This new formulation is more efficient by a factor of 2.5 in computer time and of 2.3 in memory need.

  20. Methods and models for the construction of weakly parallel tests

    NARCIS (Netherlands)

    Adema, J.J.; Adema, Jos J.

    1990-01-01

    Methods are proposed for the construction of weakly parallel tests, that is, tests with the same test information function. A mathematical programing model for constructing tests with a prespecified test information function and a heuristic for assigning items to tests such that their information

  1. Arctic curves in path models from the tangent method

    Science.gov (United States)

    Di Francesco, Philippe; Lapa, Matthew F.

    2018-04-01

    Recently, Colomo and Sportiello introduced a powerful method, known as the tangent method, for computing the arctic curve in statistical models which have a (non- or weakly-) intersecting lattice path formulation. We apply the tangent method to compute arctic curves in various models: the domino tiling of the Aztec diamond for which we recover the celebrated arctic circle; a model of Dyck paths equivalent to the rhombus tiling of a half-hexagon for which we find an arctic half-ellipse; another rhombus tiling model with an arctic parabola; the vertically symmetric alternating sign matrices, where we find the same arctic curve as for unconstrained alternating sign matrices. The latter case involves lattice paths that are non-intersecting but that are allowed to have osculating contact points, for which the tangent method was argued to still apply. For each problem we estimate the large size asymptotics of a certain one-point function using LU decomposition of the corresponding Gessel–Viennot matrices, and a reformulation of the result amenable to asymptotic analysis.

  2. Application of the simplex method of linear programming model to ...

    African Journals Online (AJOL)

    This work discussed how the simplex method of linear programming could be used to maximize the profit of any business firm using Saclux Paint Company as a case study. It equally elucidated the effect variation in the optimal result obtained from linear programming model, will have on any given firm. It was demonstrated ...

  3. Accident Analysis Methods and Models — a Systematic Literature Review

    NARCIS (Netherlands)

    Wienen, Hans Christian Augustijn; Bukhsh, Faiza Allah; Vriezekolk, E.; Wieringa, Roelf J.

    2017-01-01

    As part of our co-operation with the Telecommunication Agency of the Netherlands, we want to formulate an accident analysis method and model for use in incidents in telecommunications that cause service unavailability. In order to not re-invent the wheel, we wanted to first get an overview of all

  4. Modelling of Airship Flight Mechanics by the Projection Equivalent Method

    Directory of Open Access Journals (Sweden)

    Frantisek Jelenciak

    2015-12-01

    Full Text Available This article describes the projection equivalent method (PEM as a specific and relatively simple approach for the modelling of aircraft dynamics. By the PEM it is possible to obtain a mathematic al model of the aerodynamic forces and momentums acting on different kinds of aircraft during flight. For the PEM, it is a characteristic of it that -in principle - it provides an acceptable regression model of aerodynamic forces and momentums which exhibits reasonable and plausible behaviour from a dynamics viewpoint. The principle of this method is based on applying Newton's mechanics, which are then combined with a specific form of the finite element method to cover additional effects. The main advantage of the PEM is that it is not necessary to carry out measurements in a wind tunnel for the identification of the model's parameters. The plausible dynamical behaviour of the model can be achieved by specific correction parameters, which can be determined on the basis of experimental data obtained during the flight of the aircraft. In this article, we present the PEM as applied to an airship as well as a comparison of the data calculated by the PEM and experimental flight data.

  5. Method for modeling post-mortem biometric 3D fingerprints

    Science.gov (United States)

    Rajeev, Srijith; Shreyas, Kamath K. M.; Agaian, Sos S.

    2016-05-01

    Despite the advancements of fingerprint recognition in 2-D and 3-D domain, authenticating deformed/post-mortem fingerprints continue to be an important challenge. Prior cleansing and reconditioning of the deceased finger is required before acquisition of the fingerprint. The victim's finger needs to be precisely and carefully operated by a medium to record the fingerprint impression. This process may damage the structure of the finger, which subsequently leads to higher false rejection rates. This paper proposes a non-invasive method to perform 3-D deformed/post-mortem finger modeling, which produces a 2-D rolled equivalent fingerprint for automated verification. The presented novel modeling method involves masking, filtering, and unrolling. Computer simulations were conducted on finger models with different depth variations obtained from Flashscan3D LLC. Results illustrate that the modeling scheme provides a viable 2-D fingerprint of deformed models for automated verification. The quality and adaptability of the obtained unrolled 2-D fingerprints were analyzed using NIST fingerprint software. Eventually, the presented method could be extended to other biometric traits such as palm, foot, tongue etc. for security and administrative applications.

  6. Computational Methods for Modeling Aptamers and Designing Riboswitches

    Directory of Open Access Journals (Sweden)

    Sha Gong

    2017-11-01

    Full Text Available Riboswitches, which are located within certain noncoding RNA region perform functions as genetic “switches”, regulating when and where genes are expressed in response to certain ligands. Understanding the numerous functions of riboswitches requires computation models to predict structures and structural changes of the aptamer domains. Although aptamers often form a complex structure, computational approaches, such as RNAComposer and Rosetta, have already been applied to model the tertiary (three-dimensional (3D structure for several aptamers. As structural changes in aptamers must be achieved within the certain time window for effective regulation, kinetics is another key point for understanding aptamer function in riboswitch-mediated gene regulation. The coarse-grained self-organized polymer (SOP model using Langevin dynamics simulation has been successfully developed to investigate folding kinetics of aptamers, while their co-transcriptional folding kinetics can be modeled by the helix-based computational method and BarMap approach. Based on the known aptamers, the web server Riboswitch Calculator and other theoretical methods provide a new tool to design synthetic riboswitches. This review will represent an overview of these computational methods for modeling structure and kinetics of riboswitch aptamers and for designing riboswitches.

  7. Review: Optimization methods for groundwater modeling and management

    Science.gov (United States)

    Yeh, William W.-G.

    2015-09-01

    Optimization methods have been used in groundwater modeling as well as for the planning and management of groundwater systems. This paper reviews and evaluates the various optimization methods that have been used for solving the inverse problem of parameter identification (estimation), experimental design, and groundwater planning and management. Various model selection criteria are discussed, as well as criteria used for model discrimination. The inverse problem of parameter identification concerns the optimal determination of model parameters using water-level observations. In general, the optimal experimental design seeks to find sampling strategies for the purpose of estimating the unknown model parameters. A typical objective of optimal conjunctive-use planning of surface water and groundwater is to minimize the operational costs of meeting water demand. The optimization methods include mathematical programming techniques such as linear programming, quadratic programming, dynamic programming, stochastic programming, nonlinear programming, and the global search algorithms such as genetic algorithms, simulated annealing, and tabu search. Emphasis is placed on groundwater flow problems as opposed to contaminant transport problems. A typical two-dimensional groundwater flow problem is used to explain the basic formulations and algorithms that have been used to solve the formulated optimization problems.

  8. Acoustic 3D modeling by the method of integral equations

    Science.gov (United States)

    Malovichko, M.; Khokhlov, N.; Yavich, N.; Zhdanov, M.

    2018-02-01

    This paper presents a parallel algorithm for frequency-domain acoustic modeling by the method of integral equations (IE). The algorithm is applied to seismic simulation. The IE method reduces the size of the problem but leads to a dense system matrix. A tolerable memory consumption and numerical complexity were achieved by applying an iterative solver, accompanied by an effective matrix-vector multiplication operation, based on the fast Fourier transform (FFT). We demonstrate that, the IE system matrix is better conditioned than that of the finite-difference (FD) method, and discuss its relation to a specially preconditioned FD matrix. We considered several methods of matrix-vector multiplication for the free-space and layered host models. The developed algorithm and computer code were benchmarked against the FD time-domain solution. It was demonstrated that, the method could accurately calculate the seismic field for the models with sharp material boundaries and a point source and receiver located close to the free surface. We used OpenMP to speed up the matrix-vector multiplication, while MPI was used to speed up the solution of the system equations, and also for parallelizing across multiple sources. The practical examples and efficiency tests are presented as well.

  9. An efficient method for model refinement in diffuse optical tomography

    Science.gov (United States)

    Zirak, A. R.; Khademi, M.

    2007-11-01

    Diffuse optical tomography (DOT) is a non-linear, ill-posed, boundary value and optimization problem which necessitates regularization. Also, Bayesian methods are suitable owing to measurements data are sparse and correlated. In such problems which are solved with iterative methods, for stabilization and better convergence, the solution space must be small. These constraints subject to extensive and overdetermined system of equations which model retrieving criteria specially total least squares (TLS) must to refine model error. Using TLS is limited to linear systems which is not achievable when applying traditional Bayesian methods. This paper presents an efficient method for model refinement using regularized total least squares (RTLS) for treating on linearized DOT problem, having maximum a posteriori (MAP) estimator and Tikhonov regulator. This is done with combination Bayesian and regularization tools as preconditioner matrices, applying them to equations and then using RTLS to the resulting linear equations. The preconditioning matrixes are guided by patient specific information as well as a priori knowledge gained from the training set. Simulation results illustrate that proposed method improves the image reconstruction performance and localize the abnormally well.

  10. A new method to determine the number of experimental data using statistical modeling methods

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jung-Ho; Kang, Young-Jin; Lim, O-Kaung; Noh, Yoojeong [Pusan National University, Busan (Korea, Republic of)

    2017-06-15

    For analyzing the statistical performance of physical systems, statistical characteristics of physical parameters such as material properties need to be estimated by collecting experimental data. For accurate statistical modeling, many such experiments may be required, but data are usually quite limited owing to the cost and time constraints of experiments. In this study, a new method for determining a rea- sonable number of experimental data is proposed using an area metric, after obtaining statistical models using the information on the underlying distribution, the Sequential statistical modeling (SSM) approach, and the Kernel density estimation (KDE) approach. The area metric is used as a convergence criterion to determine the necessary and sufficient number of experimental data to be acquired. The pro- posed method is validated in simulations, using different statistical modeling methods, different true models, and different convergence criteria. An example data set with 29 data describing the fatigue strength coefficient of SAE 950X is used for demonstrating the performance of the obtained statistical models that use a pre-determined number of experimental data in predicting the probability of failure for a target fatigue life.

  11. Attempt of correlative observation of morphological synaptic connectivity by combining confocal laser-scanning microscope and FIB-SEM for immunohistochemical staining technique.

    Science.gov (United States)

    Sonomura, Takahiro; Furuta, Takahiro; Nakatani, Ikuko; Yamamoto, Yo; Honma, Satoru; Kaneko, Takeshi

    2014-11-01

    Ten years have passed since a serial block-face scanning electron microscopy (SBF-SEM) method was developed [1]. In this innovative method, samples were automatically sectioned with an ultramicrotome placed inside a scanning electron microscope column, and the block surfaces were imaged one after another by SEM to capture back-scattered electrons. The contrast-inverted images obtained by the SBF-SEM were very similar to those acquired using conventional TEM. SFB-SEM has made easy to acquire image stacks of the transmission electron microscopy (TEM) in the mesoscale, which is taken with the confocal laser-scanning microcopy(CF-LSM).Furthermore, serial-section SEM has been combined with the focused ion beam (FIB) milling method [2]. FIB-incorporated SEM (FIB-SEM) has enabled the acquisition of three-dimensional images with a higher z-axis resolution com- pared to ultramicrotome-equipped SEM.We tried immunocytochemistry for FIB-SEM and correlated this immunoreactivity with that in CF-LSM. Dendrites of neurons in the rat neostriatum were visualized using a recombinant viral vector. Moreover, the thalamostriatal afferent terminals were immunolabeled with Cy5 fluorescence for vesicular glutamate transporter 2 (VGluT2). After detection of the sites of terminals apposed to the dendrites by using CF-LSM, GFP and VGluT2 immunoreactivities were further developed for EM by using immunogold/silver enhancement and immunoperoxidase/diaminobenzidine (DAB) methods, respectively.We showed that conventional immuno-cytochemical staining for TEM was applicable to FIB-SEM. Furthermore, several synaptic contacts, which were thought to exist on the basis of CF-LSM findings, were confirmed with FIB-SEM, revealing the usefulness of the combined method of CF-LSM and FIB-SEM. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Models and methods for hot spot safety work

    DEFF Research Database (Denmark)

    Vistisen, Dorte

    2002-01-01

    Despite the fact that millions DKK each year are spent on improving roadsafety in Denmark, funds for traffic safety are limited. It is therefore vital to spend the resources as effectively as possible. This thesis is concerned with the area of traffic safety denoted "hot spot safety work", which...... is the task of improving road safety through alterations of the geometrical and environmental characteristics of the existing road network. The presently applied models and methods in hot spot safety work on the Danish road network were developed about two decades ago, when data was more limited and software...... and statistical methods less developed. The purpose of this thesis is to contribute to improving "State of the art" in Denmark. Basis for the systematic hot spot safety work are the models describing the variation in accident counts on the road network. In the thesis hierarchical models disaggregated on time...

  13. a Modeling Method of Fluttering Leaves Based on Point Cloud

    Science.gov (United States)

    Tang, J.; Wang, Y.; Zhao, Y.; Hao, W.; Ning, X.; Lv, K.; Shi, Z.; Zhao, M.

    2017-09-01

    Leaves falling gently or fluttering are common phenomenon in nature scenes. The authenticity of leaves falling plays an important part in the dynamic modeling of natural scenes. The leaves falling model has a widely applications in the field of animation and virtual reality. We propose a novel modeling method of fluttering leaves based on point cloud in this paper. According to the shape, the weight of leaves and the wind speed, three basic trajectories of leaves falling are defined, which are the rotation falling, the roll falling and the screw roll falling. At the same time, a parallel algorithm based on OpenMP is implemented to satisfy the needs of real-time in practical applications. Experimental results demonstrate that the proposed method is amenable to the incorporation of a variety of desirable effects.

  14. A MODELING METHOD OF FLUTTERING LEAVES BASED ON POINT CLOUD

    Directory of Open Access Journals (Sweden)

    J. Tang

    2017-09-01

    Full Text Available Leaves falling gently or fluttering are common phenomenon in nature scenes. The authenticity of leaves falling plays an important part in the dynamic modeling of natural scenes. The leaves falling model has a widely applications in the field of animation and virtual reality. We propose a novel modeling method of fluttering leaves based on point cloud in this paper. According to the shape, the weight of leaves and the wind speed, three basic trajectories of leaves falling are defined, which are the rotation falling, the roll falling and the screw roll falling. At the same time, a parallel algorithm based on OpenMP is implemented to satisfy the needs of real-time in practical applications. Experimental results demonstrate that the proposed method is amenable to the incorporation of a variety of desirable effects.

  15. Computational mathematics models, methods, and analysis with Matlab and MPI

    CERN Document Server

    White, Robert E

    2004-01-01

    Computational Mathematics: Models, Methods, and Analysis with MATLAB and MPI explores and illustrates this process. Each section of the first six chapters is motivated by a specific application. The author applies a model, selects a numerical method, implements computer simulations, and assesses the ensuing results. These chapters include an abundance of MATLAB code. By studying the code instead of using it as a "black box, " you take the first step toward more sophisticated numerical modeling. The last four chapters focus on multiprocessing algorithms implemented using message passing interface (MPI). These chapters include Fortran 9x codes that illustrate the basic MPI subroutines and revisit the applications of the previous chapters from a parallel implementation perspective. All of the codes are available for download from www4.ncsu.edu./~white.This book is not just about math, not just about computing, and not just about applications, but about all three--in other words, computational science. Whether us...

  16. Model of coupling with core in the Green function method

    International Nuclear Information System (INIS)

    Kamerdzhiev, S.P.; Tselyaev, V.I.

    1983-01-01

    Models of coupling with core in the method of the Green functions, presenting generalization of conventional method of chaotic phases, i.e. account of configurations of more complex than monoparticle-monohole (1p1h) configurations, have been considered. Odd nuclei are studied only to the extent when the task of odd nucleus is solved for even-even nucleus. Microscopic model of the account of delay effects in mass operator M=M(epsilon), which corresponds to the account of the effects influence only on the change of quasiparticle behaviour in magic nucleus as compared with their behaviour, described by pure model of cores, has been considered. The change results in fragmentation of monoparticle levels, which is the main effect, and in the necessity to use new basis as compared with the shell one, corresponding to inoculative quasiparticles. When formulas have been devived concrete type of mass operator M(epsilon) is not used

  17. Developing energy forecasting model using hybrid artificial intelligence method

    Institute of Scientific and Technical Information of China (English)

    Shahram Mollaiy-Berneti

    2015-01-01

    An important problem in demand planning for energy consumption is developing an accurate energy forecasting model. In fact, it is not possible to allocate the energy resources in an optimal manner without having accurate demand value. A new energy forecasting model was proposed based on the back-propagation (BP) type neural network and imperialist competitive algorithm. The proposed method offers the advantage of local search ability of BP technique and global search ability of imperialist competitive algorithm. Two types of empirical data regarding the energy demand (gross domestic product (GDP), population, import, export and energy demand) in Turkey from 1979 to 2005 and electricity demand (population, GDP, total revenue from exporting industrial products and electricity consumption) in Thailand from 1986 to 2010 were investigated to demonstrate the applicability and merits of the present method. The performance of the proposed model is found to be better than that of conventional back-propagation neural network with low mean absolute error.

  18. Unicriterion Model: A Qualitative Decision Making Method That Promotes Ethics

    Directory of Open Access Journals (Sweden)

    Fernando Guilherme Silvano Lobo Pimentel

    2011-06-01

    Full Text Available Management decision making methods frequently adopt quantitativemodels of several criteria that bypass the question of whysome criteria are considered more important than others, whichmakes more difficult the task of delivering a transparent viewof preference structure priorities that might promote ethics andlearning and serve as a basis for future decisions. To tackle thisparticular shortcoming of usual methods, an alternative qualitativemethodology of aggregating preferences based on the rankingof criteria is proposed. Such an approach delivers a simpleand transparent model for the solution of each preference conflictfaced during the management decision making process. Themethod proceeds by breaking the decision problem into ‘two criteria– two alternatives’ scenarios, and translating the problem ofchoice between alternatives to a problem of choice between criteriawhenever appropriate. The unicriterion model method is illustratedby its application in a car purchase and a house purchasedecision problem.

  19. Dynamic modeling method for infrared smoke based on enhanced discrete phase model

    Science.gov (United States)

    Zhang, Zhendong; Yang, Chunling; Zhang, Yan; Zhu, Hongbo

    2018-03-01

    The dynamic modeling of infrared (IR) smoke plays an important role in IR scene simulation systems and its accuracy directly influences the system veracity. However, current IR smoke models cannot provide high veracity, because certain physical characteristics are frequently ignored in fluid simulation; simplifying the discrete phase as a continuous phase and ignoring the IR decoy missile-body spinning. To address this defect, this paper proposes a dynamic modeling method for IR smoke, based on an enhanced discrete phase model (DPM). A mathematical simulation model based on an enhanced DPM is built and a dynamic computing fluid mesh is generated. The dynamic model of IR smoke is then established using an extended equivalent-blackbody-molecule model. Experiments demonstrate that this model realizes a dynamic method for modeling IR smoke with higher veracity.

  20. MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method.

    Science.gov (United States)

    Tuta, Jure; Juric, Matjaz B

    2018-03-24

    This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method), a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah) and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.). Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

  1. MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method

    Directory of Open Access Journals (Sweden)

    Jure Tuta

    2018-03-01

    Full Text Available This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method, a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.. Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

  2. SemGroup acquisition of central Alberta midstream : case study

    International Nuclear Information System (INIS)

    Purcell, T.

    2005-01-01

    A case study of SemGroup's acquisition of Central Alberta Midstream was presented. SemCAMS specializes in providing more efficient supply, storage, and distribution assets and services. Seminole Canada Gas is a leading independent natural gas marketing and energy asset management company that currently markets 369 MMbtu per day. The company purchases natural gas in western Canada for fee-based marketing services while also managing firm transportation contracts and providing gas storage for third party customers. SemCAMS owns the largest sour gas processor in Alberta as well as 3 sour gas processing plants, 600 miles of gathering pipeline, and a sweet gas processing plant. the company is also planning increased drilling and production activities and is now pursuing aggressive land acquisition policies. Over 25,000 square miles of land have been acquired. It was concluded that midstream companies should be customer-focused, provide reliability and guarantees, infrastructure investment and optimization. tabs., figs

  3. Critical factors in SEM 3D stereo microscopy

    DEFF Research Database (Denmark)

    Marinello, F.; Bariano, P.; Savio, E.

    2008-01-01

    This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables and measure......This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables...... factors are recognized: the first one is related to the measurement operation and the instrument set-up; the second concerns the quality of scanned images and represents the major criticality in the application of SEMs for 3D characterizations....

  4. Annual International DIC Society Conference and SEM Fall Conference

    CERN Document Server

    Reu, Phillip

    2017-01-01

    This collection represents a single volume of technical papers presented at the Annual International DIC Society Conference and SEM Fall Conference organized by the Society for Experimental Mechanics and Sandia National Laboratories and held in Philadelphia, PA, November 7-10, 2016. The volume presents early findings from experimental, standards development and various other investigations concerning digital image correlation - an important area within Experimental Mechanics. The area of Digital Image Correlation has been an integral track within the SEM Annual Conference spearheaded by Professor Michael Sutton from the University of South Carolina. In 2016, the SEM and Sandia joined their collaborative strengths to launch a standing fall meeting focusing specifically on developments in the area of Digital Image Correlation. The contributed papers within this volume span numerous technical aspects of DIC including standards development for the industry. .

  5. SemVisM: semantic visualizer for medical image

    Science.gov (United States)

    Landaeta, Luis; La Cruz, Alexandra; Baranya, Alexander; Vidal, María.-Esther

    2015-01-01

    SemVisM is a toolbox that combines medical informatics and computer graphics tools for reducing the semantic gap between low-level features and high-level semantic concepts/terms in the images. This paper presents a novel strategy for visualizing medical data annotated semantically, combining rendering techniques, and segmentation algorithms. SemVisM comprises two main components: i) AMORE (A Modest vOlume REgister) to handle input data (RAW, DAT or DICOM) and to initially annotate the images using terms defined on medical ontologies (e.g., MesH, FMA or RadLex), and ii) VOLPROB (VOlume PRObability Builder) for generating the annotated volumetric data containing the classified voxels that belong to a particular tissue. SemVisM is built on top of the semantic visualizer ANISE.1

  6. Model parameterization as method for data analysis in dendroecology

    Science.gov (United States)

    Tychkov, Ivan; Shishov, Vladimir; Popkova, Margarita

    2017-04-01

    There is no argue in usefulness of process-based models in ecological studies. Only limitations is how developed algorithm of model and how it will be applied for research. Simulation of tree-ring growth based on climate provides valuable information of tree-ring growth response on different environmental conditions, but also shares light on species-specifics of tree-ring growth process. Visual parameterization of the Vaganov-Shashkin model, allows to estimate non-linear response of tree-ring growth based on daily climate data: daily temperature, estimated day light and soil moisture. Previous using of the VS-Oscilloscope (a software tool of the visual parameterization) shows a good ability to recreate unique patterns of tree-ring growth for coniferous species in Siberian Russia, USA, China, Mediterranean Spain and Tunisia. But using of the models mostly is one-sided to better understand different tree growth processes, opposite to statistical methods of analysis (e.g. Generalized Linear Models, Mixed Models, Structural Equations.) which can be used for reconstruction and forecast. Usually the models are used either for checking of new hypothesis or quantitative assessment of physiological tree growth data to reveal a growth process mechanisms, while statistical methods used for data mining assessment and as a study tool itself. The high sensitivity of the model's VS-parameters reflects the ability of the model to simulate tree-ring growth and evaluates value of limiting growth climate factors. Precise parameterization of VS-Oscilloscope provides valuable information about growth processes of trees and under what conditions these processes occur (e.g. day of growth season onset, length of season, value of minimal/maximum temperature for tree-ring growth, formation of wide or narrow rings etc.). The work was supported by the Russian Science Foundation (RSF # 14-14-00219)

  7. Modeling of radionuclide migration through porous material with meshless method

    International Nuclear Information System (INIS)

    Vrankar, L.; Turk, G.; Runovc, F.

    2005-01-01

    To assess the long term safety of a radioactive waste disposal system, mathematical models are used to describe groundwater flow, chemistry and potential radionuclide migration through geological formations. A number of processes need to be considered when predicting the movement of radionuclides through the geosphere. The most important input data are obtained from field measurements, which are not completely available for all regions of interest. For example, the hydraulic conductivity as an input parameter varies from place to place. In such cases geostatistical science offers a variety of spatial estimation procedures. Methods for solving the solute transport equation can also be classified as Eulerian, Lagrangian and mixed. The numerical solution of partial differential equations (PDE) is usually obtained by finite difference methods (FDM), finite element methods (FEM), or finite volume methods (FVM). Kansa introduced the concept of solving partial differential equations using radial basis functions (RBF) for hyperbolic, parabolic and elliptic PDEs. Our goal was to present a relatively new approach to the modelling of radionuclide migration through the geosphere using radial basis function methods in Eulerian and Lagrangian coordinates. Radionuclide concentrations will also be calculated in heterogeneous and partly heterogeneous 2D porous media. We compared the meshless method with the traditional finite difference scheme. (author)

  8. CAD-based automatic modeling method for Geant4 geometry model through MCAM

    International Nuclear Information System (INIS)

    Wang, D.; Nie, F.; Wang, G.; Long, P.; LV, Z.

    2013-01-01

    The full text of publication follows. Geant4 is a widely used Monte Carlo transport simulation package. Before calculating using Geant4, the calculation model need be established which could be described by using Geometry Description Markup Language (GDML) or C++ language. However, it is time-consuming and error-prone to manually describe the models by GDML. Automatic modeling methods have been developed recently, but there are some problems that exist in most present modeling programs, specially some of them were not accurate or adapted to specifically CAD format. To convert the GDML format models to CAD format accurately, a Geant4 Computer Aided Design (CAD) based modeling method was developed for automatically converting complex CAD geometry model into GDML geometry model. The essence of this method was dealing with CAD model represented with boundary representation (B-REP) and GDML model represented with constructive solid geometry (CSG). At first, CAD model was decomposed to several simple solids which had only one close shell. And then the simple solid was decomposed to convex shell set. Then corresponding GDML convex basic solids were generated by the boundary surfaces getting from the topological characteristic of a convex shell. After the generation of these solids, GDML model was accomplished with series boolean operations. This method was adopted in CAD/Image-based Automatic Modeling Program for Neutronics and Radiation Transport (MCAM), and tested with several models including the examples in Geant4 install package. The results showed that this method could convert standard CAD model accurately, and can be used for Geant4 automatic modeling. (authors)

  9. OpenCV-Based Nanomanipulation Information Extraction and the Probe Operation in SEM

    Directory of Open Access Journals (Sweden)

    Dongjie Li

    2015-02-01

    Full Text Available Aimed at the established telenanomanipulation system, the method of extracting location information and the strategies of probe operation were studied in this paper. First, the machine learning algorithm of OpenCV was used to extract location information from SEM images. Thus nanowires and probe in SEM images can be automatically tracked and the region of interest (ROI can be marked quickly. Then the location of nanowire and probe can be extracted from the ROI. To study the probe operation strategy, the Van der Waals force between probe and a nanowire was computed; thus relevant operating parameters can be obtained. With these operating parameters, the nanowire in 3D virtual environment can be preoperated and an optimal path of the probe can be obtained. The actual probe runs automatically under the telenanomanipulation system's control. Finally, experiments were carried out to verify the above methods, and results show the designed methods have achieved the expected effect.

  10. Evaluation of internal noise methods for Hotelling observer models

    International Nuclear Information System (INIS)

    Zhang Yani; Pham, Binh T.; Eckstein, Miguel P.

    2007-01-01

    The inclusion of internal noise in model observers is a common method to allow for quantitative comparisons between human and model observer performance in visual detection tasks. In this article, we studied two different strategies for inserting internal noise into Hotelling model observers. In the first strategy, internal noise was added to the output of individual channels: (a) Independent nonuniform channel noise, (b) independent uniform channel noise. In the second strategy, internal noise was added to the decision variable arising from the combination of channel responses. The standard deviation of the zero mean internal noise was either constant or proportional to: (a) the decision variable's standard deviation due to the external noise, (b) the decision variable's variance caused by the external noise, (c) the decision variable magnitude on a trial to trial basis. We tested three model observers: square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO) using a four alternative forced choice (4AFC) signal known exactly but variable task with a simulated signal embedded in real x-ray coronary angiogram backgrounds. The results showed that the internal noise method that led to the best prediction of human performance differed across the studied model observers. The CHO model best predicted human observer performance with the channel internal noise. The HO and LGHO best predicted human observer performance with the decision variable internal noise. The present results might guide researchers with the choice of methods to include internal noise into Hotelling model observers when evaluating and optimizing medical image quality

  11. A Review of Distributed Parameter Groundwater Management Modeling Methods

    Science.gov (United States)

    Gorelick, Steven M.

    1983-04-01

    Models which solve the governing groundwater flow or solute transport equations in conjunction with optimization techniques, such as linear and quadratic programing, are powerful aquifer management tools. Groundwater management models fall in two general categories: hydraulics or policy evaluation and water allocation. Groundwater hydraulic management models enable the determination of optimal locations and pumping rates of numerous wells under a variety of restrictions placed upon local drawdown, hydraulic gradients, and water production targets. Groundwater policy evaluation and allocation models can be used to study the influence upon regional groundwater use of institutional policies such as taxes and quotas. Furthermore, fairly complex groundwater-surface water allocation problems can be handled using system decomposition and multilevel optimization. Experience from the few real world applications of groundwater optimization-management techniques is summarized. Classified separately are methods for groundwater quality management aimed at optimal waste disposal in the subsurface. This classification is composed of steady state and transient management models that determine disposal patterns in such a way that water quality is protected at supply locations. Classes of research missing from the literature are groundwater quality management models involving nonlinear constraints, models which join groundwater hydraulic and quality simulations with political-economic management considerations, and management models that include parameter uncertainty.

  12. Protons, ions, electrons and the future of the SEM

    International Nuclear Information System (INIS)

    Joy, D C

    2010-01-01

    The Scanning Electron Microscope (SEM) is the most widely used high performance microscope in all fields of science but it is now reaching the theoretical limits of its performance. While advances in sources, optics, and detectors, can result in some improvement in performance the ultimate resolution is limited by fundamental physical constraints. One potential alternative is a scanning microscope utilizing light ions such as H+ and He+ . Such an instrument shares all of the benefits of the conventional SEM but is free from the constraints encountered when using electrons and could significantly extend the scope and success of scanning microscopy.

  13. Storm surge model based on variational data assimilation method

    Directory of Open Access Journals (Sweden)

    Shi-li Huang

    2010-06-01

    Full Text Available By combining computation and observation information, the variational data assimilation method has the ability to eliminate errors caused by the uncertainty of parameters in practical forecasting. It was applied to a storm surge model based on unstructured grids with high spatial resolution meant for improving the forecasting accuracy of the storm surge. By controlling the wind stress drag coefficient, the variation-based model was developed and validated through data assimilation tests in an actual storm surge induced by a typhoon. In the data assimilation tests, the model accurately identified the wind stress drag coefficient and obtained results close to the true state. Then, the actual storm surge induced by Typhoon 0515 was forecast by the developed model, and the results demonstrate its efficiency in practical application.

  14. Coarse Analysis of Microscopic Models using Equation-Free Methods

    DEFF Research Database (Denmark)

    Marschler, Christian

    of these models might be high-dimensional, the properties of interest are usually macroscopic and lowdimensional in nature. Examples are numerous and not necessarily restricted to computer models. For instance, the power output, energy consumption and temperature of engines are interesting quantities....... Applications include the learning behavior in the barn owl’s auditory system, traffic jam formation in an optimal velocity model for circular car traffic and oscillating behavior of pedestrian groups in a counter-flow through a corridor with narrow door. The methods do not only quantify interesting properties...... in these models (learning outcome, traffic jam density, oscillation period), but also allow to investigate unstable solutions, which are important information to determine basins of attraction of stable solutions and thereby reveal information on the long-term behavior of an initial state....

  15. Numerical methods for the Lévy LIBOR model

    DEFF Research Database (Denmark)

    Papapantoleon, Antonis; Skovmand, David

    2010-01-01

    but the methods are generally slow. We propose an alternative approximation scheme based on Picard iterations. Our approach is similar in accuracy to the full numerical solution, but with the feature that each rate is, unlike the standard method, evolved independently of the other rates in the term structure....... This enables simultaneous calculation of derivative prices of different maturities using parallel computing. We include numerical illustrations of the accuracy and speed of our method pricing caplets.......The aim of this work is to provide fast and accurate approximation schemes for the Monte-Carlo pricing of derivatives in the L\\'evy LIBOR model of Eberlein and \\"Ozkan (2005). Standard methods can be applied to solve the stochastic differential equations of the successive LIBOR rates...

  16. Numerical Methods for the Lévy LIBOR Model

    DEFF Research Database (Denmark)

    Papapantoleon, Antonis; Skovmand, David

    are generally slow. We propose an alternative approximation scheme based on Picard iterations. Our approach is similar in accuracy to the full numerical solution, but with the feature that each rate is, unlike the standard method, evolved independently of the other rates in the term structure. This enables...... simultaneous calculation of derivative prices of different maturities using parallel computing. We include numerical illustrations of the accuracy and speed of our method pricing caplets.......The aim of this work is to provide fast and accurate approximation schemes for the Monte-Carlo pricing of derivatives in the Lévy LIBOR model of Eberlein and Özkan (2005). Standard methods can be applied to solve the stochastic differential equations of the successive LIBOR rates but the methods...

  17. Hybrid perturbation methods based on statistical time series models

    Science.gov (United States)

    San-Juan, Juan Félix; San-Martín, Montserrat; Pérez, Iván; López, Rosario

    2016-04-01

    In this work we present a new methodology for orbit propagation, the hybrid perturbation theory, based on the combination of an integration method and a prediction technique. The former, which can be a numerical, analytical or semianalytical theory, generates an initial approximation that contains some inaccuracies derived from the fact that, in order to simplify the expressions and subsequent computations, not all the involved forces are taken into account and only low-order terms are considered, not to mention the fact that mathematical models of perturbations not always reproduce physical phenomena with absolute precision. The prediction technique, which can be based on either statistical time series models or computational intelligence methods, is aimed at modelling and reproducing missing dynamics in the previously integrated approximation. This combination results in the precision improvement of conventional numerical, analytical and semianalytical theories for determining the position and velocity of any artificial satellite or space debris object. In order to validate this methodology, we present a family of three hybrid orbit propagators formed by the combination of three different orders of approximation of an analytical theory and a statistical time series model, and analyse their capability to process the effect produced by the flattening of the Earth. The three considered analytical components are the integration of the Kepler problem, a first-order and a second-order analytical theories, whereas the prediction technique is the same in the three cases, namely an additive Holt-Winters method.

  18. Soybean yield modeling using bootstrap methods for small samples

    Energy Technology Data Exchange (ETDEWEB)

    Dalposso, G.A.; Uribe-Opazo, M.A.; Johann, J.A.

    2016-11-01

    One of the problems that occur when working with regression models is regarding the sample size; once the statistical methods used in inferential analyzes are asymptotic if the sample is small the analysis may be compromised because the estimates will be biased. An alternative is to use the bootstrap methodology, which in its non-parametric version does not need to guess or know the probability distribution that generated the original sample. In this work we used a set of soybean yield data and physical and chemical soil properties formed with fewer samples to determine a multiple linear regression model. Bootstrap methods were used for variable selection, identification of influential points and for determination of confidence intervals of the model parameters. The results showed that the bootstrap methods enabled us to select the physical and chemical soil properties, which were significant in the construction of the soybean yield regression model, construct the confidence intervals of the parameters and identify the points that had great influence on the estimated parameters. (Author)

  19. A hierarchical network modeling method for railway tunnels safety assessment

    Science.gov (United States)

    Zhou, Jin; Xu, Weixiang; Guo, Xin; Liu, Xumin

    2017-02-01

    Using network theory to model risk-related knowledge on accidents is regarded as potential very helpful in risk management. A large amount of defects detection data for railway tunnels is collected in autumn every year in China. It is extremely important to discover the regularities knowledge in database. In this paper, based on network theories and by using data mining techniques, a new method is proposed for mining risk-related regularities to support risk management in railway tunnel projects. A hierarchical network (HN) model which takes into account the tunnel structures, tunnel defects, potential failures and accidents is established. An improved Apriori algorithm is designed to rapidly and effectively mine correlations between tunnel structures and tunnel defects. Then an algorithm is presented in order to mine the risk-related regularities table (RRT) from the frequent patterns. At last, a safety assessment method is proposed by consideration of actual defects and possible risks of defects gained from the RRT. This method cannot only generate the quantitative risk results but also reveal the key defects and critical risks of defects. This paper is further development on accident causation network modeling methods which can provide guidance for specific maintenance measure.

  20. A Data-Driven Approach to SEM Development at a Two-Year College

    Science.gov (United States)

    Pirius, Landon K.

    2014-01-01

    This article explores implementation of strategic enrollment management (SEM) at a two-year college and why SEM is critical to the long-term viability of an institution. This article also outlines the five initial steps needed to implement SEM, including identifying SEM leadership, building a SEM committee, developing a common understanding of…

  1. A Kriging Model Based Finite Element Model Updating Method for Damage Detection

    Directory of Open Access Journals (Sweden)

    Xiuming Yang

    2017-10-01

    Full Text Available Model updating is an effective means of damage identification and surrogate modeling has attracted considerable attention for saving computational cost in finite element (FE model updating, especially for large-scale structures. In this context, a surrogate model of frequency is normally constructed for damage identification, while the frequency response function (FRF is rarely used as it usually changes dramatically with updating parameters. This paper presents a new surrogate model based model updating method taking advantage of the measured FRFs. The Frequency Domain Assurance Criterion (FDAC is used to build the objective function, whose nonlinear response surface is constructed by the Kriging model. Then, the efficient global optimization (EGO algorithm is introduced to get the model updating results. The proposed method has good accuracy and robustness, which have been verified by a numerical simulation of a cantilever and experimental test data of a laboratory three-story structure.

  2. Automated transmission-mode scanning electron microscopy (tSEM for large volume analysis at nanoscale resolution.

    Directory of Open Access Journals (Sweden)

    Masaaki Kuwajima

    Full Text Available Transmission-mode scanning electron microscopy (tSEM on a field emission SEM platform was developed for efficient and cost-effective imaging of circuit-scale volumes from brain at nanoscale resolution. Image area was maximized while optimizing the resolution and dynamic range necessary for discriminating key subcellular structures, such as small axonal, dendritic and glial processes, synapses, smooth endoplasmic reticulum, vesicles, microtubules, polyribosomes, and endosomes which are critical for neuronal function. Individual image fields from the tSEM system were up to 4,295 µm(2 (65.54 µm per side at 2 nm pixel size, contrasting with image fields from a modern transmission electron microscope (TEM system, which were only 66.59 µm(2 (8.160 µm per side at the same pixel size. The tSEM produced outstanding images and had reduced distortion and drift relative to TEM. Automated stage and scan control in tSEM easily provided unattended serial section imaging and montaging. Lens and scan properties on both TEM and SEM platforms revealed no significant nonlinear distortions within a central field of ∼100 µm(2 and produced near-perfect image registration across serial sections using the computational elastic alignment tool in Fiji/TrakEM2 software, and reliable geometric measurements from RECONSTRUCT™ or Fiji/TrakEM2 software. Axial resolution limits the analysis of small structures contained within a section (∼45 nm. Since this new tSEM is non-destructive, objects within a section can be explored at finer axial resolution in TEM tomography with current methods. Future development of tSEM tomography promises thinner axial resolution producing nearly isotropic voxels and should provide within-section analyses of structures without changing platforms. Brain was the test system given our interest in synaptic connectivity and plasticity; however, the new tSEM system is readily applicable to other biological systems.

  3. Does your SEM really tell the truth? How would you know? Part 2.

    Science.gov (United States)

    Postek, Michael T; Vladár, András E; Purushotham, Kavuri P

    2014-01-01

    The scanning electron microscope (SEM) has gone through a tremendous evolution to become indispensable for many and diverse scientific and industrial applications. The improvements have significantly enriched and augmented the overall SEM performance and have made the instrument far easier to operate. But, the ease of operation also might lead, through operator complacency, to poor results. In addition, the user friendliness has seemingly reduced the need for thorough operator training for using these complex instruments. One might then conclude that the SEM is just a very expensive digital camera or another peripheral device for a computer. Hence, a person using the instrument may be lulled into thinking that all of the potential pitfalls have been eliminated and they believe everything they see on the micrograph is always correct. But, this may not be the case. An earlier paper (Part 1), discussed some of the potential issues related to signal generation in the SEM, instrument calibration, electron beam interactions and the need for physics-based modeling to understand the actual image formation mechanisms. All these were summed together in a discussion of how these issues effect measurements made with the instrument. This second paper discusses another major issue confronting the microscopist: electron-beam-induced specimen contamination. Over the years, NIST has done a great deal of research into the issue of sample contamination and its removal and elimination and some of this work is reviewed and discussed here. © 2013 Wiley Periodicals, Inc.

  4. Are the evidences of forensic entomology preserved in ethanol suitable for SEM studies?

    Science.gov (United States)

    López-Esclapez, Raquel; García, María-Dolores; Arnaldos, María-Isabel; Presa, Juan José; Ubero-Pascal, Nicolás

    2014-07-01

    In forensic practice, the use of arthropod evidences to estimate the postmortem interval is a very good approach when the elapsed time from death is long, but it requires the correct identification of the specimens. This is a crucial step, not always easy to achieve, in particular when dealing with immature specimens. In this case, scanning electronic microscopy (SEM) can be useful, but the techniques used to preserve specimens in forensic practice are usually different from those used to prepare specimens for SEM studies. To determine whether forensic evidences preserving techniques are also compatible with SEM analysis, we have compared specimens of all the immature stages of Calliphora vicina Robineau-Desvoidy, 1830 (Diptera, Calliphoridae) preserved in 70% ethanol, with others prepared with aldehydic fixative techniques that are more appropriate for SEM studies. At the same time, two drying techniques have also been compared with both fixative techniques, the critical point drying and air-drying following with hexamethyldisilizane treatment (HMDS). Our results indicate that there are not basis against recommending the use of ethanol to preserve forensic entomological evidences and that both drying methods appear to offer good results for second and third instar larvae, although HMDS behaves better with eggs and pupae. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. SD-SEM: sparse-dense correspondence for 3D reconstruction of microscopic samples.

    Science.gov (United States)

    Baghaie, Ahmadreza; Tafti, Ahmad P; Owen, Heather A; D'Souza, Roshan M; Yu, Zeyun

    2017-06-01

    Scanning electron microscopy (SEM) imaging has been a principal component of many studies in biomedical, mechanical, and materials sciences since its emergence. Despite the high resolution of captured images, they remain two-dimensional (2D). In this work, a novel framework using sparse-dense correspondence is introduced and investigated for 3D reconstruction of stereo SEM images. SEM micrographs from microscopic samples are captured by tilting the specimen stage by a known angle. The pair of SEM micrographs is then rectified using sparse scale invariant feature transform (SIFT) features/descriptors and a contrario RANSAC for matching outlier removal to ensure a gross horizontal displacement between corresponding points. This is followed by dense correspondence estimation using dense SIFT descriptors and employing a factor graph representation of the energy minimization functional and loopy belief propagation (LBP) as means of optimization. Given the pixel-by-pixel correspondence and the tilt angle of the specimen stage during the acquisition of micrographs, depth can be recovered. Extensive tests reveal the strength of the proposed method for high-quality reconstruction of microscopic samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Character expansion methods for matrix models of dually weighted graphs

    International Nuclear Information System (INIS)

    Kazakov, V.A.; Staudacher, M.; Wynter, T.

    1996-01-01

    We consider generalized one-matrix models in which external fields allow control over the coordination numbers on both the original and dual lattices. We rederive in a simple fashion a character expansion formula for these models originally due to Itzykson and Di Francesco, and then demonstrate how to take the large N limit of this expansion. The relationship to the usual matrix model resolvent is elucidated. Our methods give as a by-product an extremely simple derivation of the Migdal integral equation describing the large N limit of the Itzykson-Zuber formula. We illustrate and check our methods by analysing a number of models solvable by traditional means. We then proceed to solve a new model: a sum over planar graphs possessing even coordination numbers on both the original and the dual lattice. We conclude by formulating equations for the case of arbitrary sets of even, self-dual coupling constants. This opens the way for studying the deep problem of phase transitions from random to flat lattices. (orig.). With 4 figs

  7. Martian Radiative Transfer Modeling Using the Optimal Spectral Sampling Method

    Science.gov (United States)

    Eluszkiewicz, J.; Cady-Pereira, K.; Uymin, G.; Moncet, J.-L.

    2005-01-01

    The large volume of existing and planned infrared observations of Mars have prompted the development of a new martian radiative transfer model that could be used in the retrievals of atmospheric and surface properties. The model is based on the Optimal Spectral Sampling (OSS) method [1]. The method is a fast and accurate monochromatic technique applicable to a wide range of remote sensing platforms (from microwave to UV) and was originally developed for the real-time processing of infrared and microwave data acquired by instruments aboard the satellites forming part of the next-generation global weather satellite system NPOESS (National Polarorbiting Operational Satellite System) [2]. As part of our on-going research related to the radiative properties of the martian polar caps, we have begun the development of a martian OSS model with the goal of using it to perform self-consistent atmospheric corrections necessary to retrieve caps emissivity from the Thermal Emission Spectrometer (TES) spectra. While the caps will provide the initial focus area for applying the new model, it is hoped that the model will be of interest to the wider Mars remote sensing community.

  8. A Method to Identify Flight Obstacles on Digital Surface Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; LIN Xinggang; SUN Shouyu; WANG Youzhi

    2005-01-01

    In modern low-altitude terrain-following guidance, a constructing method of the digital surface model (DSM) is presented in the paper to reduce the threat to flying vehicles of tall surface features for safe flight. The relationship between an isolated obstacle size and the intervals of vertical- and cross-section in the DSM model is established. The definition and classification of isolated obstacles are proposed, and a method for determining such isolated obstacles in the DSM model is given. The simulation of a typical urban district shows that when the vertical- and cross-section DSM intervals are between 3 m and 25 m, the threat to terrain-following flight at low-altitude is reduced greatly, and the amount of data required by the DSM model for monitoring in real time a flying vehicle is also smaller. Experiments show that the optimal results are for an interval of 12.5 m in the vertical- and cross-sections in the DSM model, with a 1:10 000 DSM scale grade.

  9. Impacts modeling using the SPH particulate method. Case study

    International Nuclear Information System (INIS)

    Debord, R.

    1999-01-01

    The aim of this study is the modeling of the impact of melted metal on the reactor vessel head in the case of a core-meltdown accident. Modeling using the classical finite-element method alone is not sufficient but requires a coupling with particulate methods in order to take into account the behaviour of the corium. After a general introduction about particulate methods, the Nabor and SPH (smoothed particle hydrodynamics) methods are described. Then, the theoretical and numerical reliability of the SPH method is determined using simple cases. In particular, the number of neighbours significantly influences the preciseness of calculations. Also, the mesh of the structure must be adapted to the mesh of the fluid in order to reduce the edge effects. Finally, this study has shown that the values of artificial velocity coefficients used in the simulation of the BERDA test performed by the FZK Karlsruhe (Germany) are not correct. The domain of use of these coefficients was precised during a low speed impact. (J.S.)

  10. A Parsimonious Bootstrap Method to Model Natural Inflow Energy Series

    Directory of Open Access Journals (Sweden)

    Fernando Luiz Cyrino Oliveira

    2014-01-01

    Full Text Available The Brazilian energy generation and transmission system is quite peculiar in its dimension and characteristics. As such, it can be considered unique in the world. It is a high dimension hydrothermal system with huge participation of hydro plants. Such strong dependency on hydrological regimes implies uncertainties related to the energetic planning, requiring adequate modeling of the hydrological time series. This is carried out via stochastic simulations of monthly inflow series using the family of Periodic Autoregressive models, PAR(p, one for each period (month of the year. In this paper it is shown the problems in fitting these models by the current system, particularly the identification of the autoregressive order “p” and the corresponding parameter estimation. It is followed by a proposal of a new approach to set both the model order and the parameters estimation of the PAR(p models, using a nonparametric computational technique, known as Bootstrap. This technique allows the estimation of reliable confidence intervals for the model parameters. The obtained results using the Parsimonious Bootstrap Method of Moments (PBMOM produced not only more parsimonious model orders but also adherent stochastic scenarios and, in the long range, lead to a better use of water resources in the energy operation planning.

  11. Modeling Music Emotion Judgments Using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    Naresh N. Vempala

    2018-01-01

    Full Text Available Emotion judgments and five channels of physiological data were obtained from 60 participants listening to 60 music excerpts. Various machine learning (ML methods were used to model the emotion judgments inclusive of neural networks, linear regression, and random forests. Input for models of perceived emotion consisted of audio features extracted from the music recordings. Input for models of felt emotion consisted of physiological features extracted from the physiological recordings. Models were trained and interpreted with consideration of the classic debate in music emotion between cognitivists and emotivists. Our models supported a hybrid position wherein emotion judgments were influenced by a combination of perceived and felt emotions. In comparing the different ML approaches that were used for modeling, we conclude that neural networks were optimal, yielding models that were flexible as well as interpretable. Inspection of a committee machine, encompassing an ensemble of networks, revealed that arousal judgments were predominantly influenced by felt emotion, whereas valence judgments were predominantly influenced by perceived emotion.

  12. Finite-element method modeling of hyper-frequency structures

    International Nuclear Information System (INIS)

    Zhang, Min

    1990-01-01

    The modelization of microwave propagation problems, including Eigen-value problem and scattering problem, is accomplished by the finite element method with vector functional and scalar functional. For Eigen-value problem, propagation modes in waveguides and resonant modes in cavities can be calculated in a arbitrarily-shaped structure with inhomogeneous material. Several microwave structures are resolved in order to verify the program. One drawback associated with the vector functional is the appearance of spurious or non-physical solutions. A penalty function method has been introduced to reduce spurious' solutions. The adaptive charge method is originally proposed in this thesis to resolve waveguide scattering problem. This method, similar to VSWR measuring technique, is more efficient to obtain the reflection coefficient than the matrix method. Two waveguide discontinuity structures are calculated by the two methods and their results are compared. The adaptive charge method is also applied to a microwave plasma excitor. It allows us to understand the role of different physical parameters of excitor in the coupling of microwave energy to plasma mode and the mode without plasma. (author) [fr

  13. New Models and Methods for the Electroweak Scale

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, Linda [The Ohio State Univ., Columbus, OH (United States). Dept. of Physics

    2017-09-26

    This is the Final Technical Report to the US Department of Energy for grant DE-SC0013529, New Models and Methods for the Electroweak Scale, covering the time period April 1, 2015 to March 31, 2017. The goal of this project was to maximize the understanding of fundamental weak scale physics in light of current experiments, mainly the ongoing run of the Large Hadron Collider and the space based satellite experiements searching for signals Dark Matter annihilation or decay. This research program focused on the phenomenology of supersymmetry, Higgs physics, and Dark Matter. The properties of the Higgs boson are currently being measured by the Large Hadron collider, and could be a sensitive window into new physics at the weak scale. Supersymmetry is the leading theoretical candidate to explain the natural nessof the electroweak theory, however new model space must be explored as the Large Hadron collider has disfavored much minimal model parameter space. In addition the nature of Dark Matter, the mysterious particle that makes up 25% of the mass of the universe is still unknown. This project sought to address measurements of the Higgs boson couplings to the Standard Model particles, new LHC discovery scenarios for supersymmetric particles, and new measurements of Dark Matter interactions with the Standard Model both in collider production and annihilation in space. Accomplishments include new creating tools for analyses of Dark Matter models in Dark Matter which annihilates into multiple Standard Model particles, including new visualizations of bounds for models with various Dark Matter branching ratios; benchmark studies for new discovery scenarios of Dark Matter at the Large Hardon Collider for Higgs-Dark Matter and gauge boson-Dark Matter interactions; New target analyses to detect direct decays of the Higgs boson into challenging final states like pairs of light jets, and new phenomenological analysis of non-minimal supersymmetric models, namely the set of Dirac

  14. Modeling of Methods to Control Heat-Consumption Efficiency

    Science.gov (United States)

    Tsynaeva, E. A.; Tsynaeva, A. A.

    2016-11-01

    In this work, consideration has been given to thermophysical processes in automated heat consumption control systems (AHCCSs) of buildings, flow diagrams of these systems, and mathematical models describing the thermophysical processes during the systems' operation; an analysis of adequacy of the mathematical models has been presented. A comparison has been made of the operating efficiency of the systems and the methods to control the efficiency. It has been determined that the operating efficiency of an AHCCS depends on its diagram and the temperature chart of central quality control (CQC) and also on the temperature of a low-grade heat source for the system with a heat pump.

  15. Modeling of electromigration salt removal methods in building materials

    DEFF Research Database (Denmark)

    Johannesson, Björn; Ottosen, Lisbeth M.

    2008-01-01

    for salt attack of various kinds, is one potential method to preserve old building envelopes. By establishing a model for ionic multi-species diffusion, which also accounts for external applied electrical fields, it is proposed that an important complement to the experimental tests and that verification...... with its ionic mobility properties. It is, further, assumed that Gauss’s law can be used to calculate the internal electrical field induced by the diffusion it self. In this manner the external electrical field applied can be modeled, simply, by assigning proper boundary conditions for the equation...

  16. (Environmental and geophysical modeling, fracture mechanics, and boundary element methods)

    Energy Technology Data Exchange (ETDEWEB)

    Gray, L.J.

    1990-11-09

    Technical discussions at the various sites visited centered on application of boundary integral methods for environmental modeling, seismic analysis, and computational fracture mechanics in composite and smart'' materials. The traveler also attended the International Association for Boundary Element Methods Conference at Rome, Italy. While many aspects of boundary element theory and applications were discussed in the papers, the dominant topic was the analysis and application of hypersingular equations. This has been the focus of recent work by the author, and thus the conference was highly relevant to research at ORNL.

  17. Complex Data Modeling and Computationally Intensive Statistical Methods

    CERN Document Server

    Mantovan, Pietro

    2010-01-01

    The last years have seen the advent and development of many devices able to record and store an always increasing amount of complex and high dimensional data; 3D images generated by medical scanners or satellite remote sensing, DNA microarrays, real time financial data, system control datasets. The analysis of this data poses new challenging problems and requires the development of novel statistical models and computational methods, fueling many fascinating and fast growing research areas of modern statistics. The book offers a wide variety of statistical methods and is addressed to statistici

  18. Stress description model by non destructive magnetic methods

    International Nuclear Information System (INIS)

    Flambard, C.; Grossiord, J.L.; Tourrenc, P.

    1983-01-01

    Since a few years, CETIM investigates analysis possibilities of materials, by developing a method founded on observation of ferromagnetic noise. By experiments, correlations have become obvious between state of the material and recorded signal. These correlations open to industrial applications to measure stresses and strains in elastic and plastic ranges. This article starts with a brief historical account and theoretical backgrounds of the method. The experimental frame of this research is described, and the main results are analyzed. Theoretically, a model was built up, and we present it. It seems in agreement with some experimental observations. The main results concerning stress application, thermal and surface treatments (decarbonizing) are presented [fr

  19. Item bias detection in the Hospital Anxiety and Depression Scale using structural equation modeling: comparison with other item bias detection methods

    NARCIS (Netherlands)

    Verdam, M.G.E.; Oort, F.J.; Sprangers, M.A.G.

    Purpose Comparison of patient-reported outcomes may be invalidated by the occurrence of item bias, also known as differential item functioning. We show two ways of using structural equation modeling (SEM) to detect item bias: (1) multigroup SEM, which enables the detection of both uniform and

  20. Alternative wind power modeling methods using chronological and load duration curve production cost models

    Energy Technology Data Exchange (ETDEWEB)

    Milligan, M R

    1996-04-01

    As an intermittent resource, capturing the temporal variation in windpower is an important issue in the context of utility production cost modeling. Many of the production cost models use a method that creates a cumulative probability distribution that is outside the time domain. The purpose of this report is to examine two production cost models that represent the two major model types: chronological and load duration cure models. This report is part of the ongoing research undertaken by the Wind Technology Division of the National Renewable Energy Laboratory in utility modeling and wind system integration.