Control volume based modelling of compressible flow in reciprocating machines
Andersen, Stig Kildegård; Thomsen, Per Grove; Carlsen, Henrik
2004-01-01
, and multidimensional effects must be calculated using empirical correlations; correlations for steady state flow can be used as an approximation. A transformation that assumes ideal gas is presented for transforming equations for masses and energies in control volumes into the corresponding pressures and temperatures......An approach to modelling unsteady compressible flow that is primarily one dimensional is presented. The approach was developed for creating distributed models of machines with reciprocating pistons but it is not limited to this application. The approach is based on the integral form of the unsteady...... conservation laws for mass, energy, and momentum applied to a staggered mesh consisting of two overlapping strings of control volumes. Loss mechanisms can be included directly in the governing equations of models by including them as terms in the conservation laws. Heat transfer, flow friction...
Toyama, H; Endo, Y; Ejima, Y; Matsubara, M; Kurosawa, S
2011-07-01
In neonates, small changes in tidal volumes (V(T)) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual V(T)). We evaluated the accuracy of three different ventilators to deliver small V(T) during volume-controlled ventilation. We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (V(TV)) and actual V(T) to the test lung were measured using Ventrak respiration monitors at set V(T) (30 ml). The gas volume increase of the breathing circuit was then calculated. Tidal volumes of the SV300 and PB840 in both lung models were similar to the set V(T) and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual V(T). V(TV) of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set V(T), and actual V(T) were similar to set V(T) in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring V(T) close to the lung could match actual V(T) to almost the same value as the set V(T) however the gas volume of the breathing circuit was increased. If an accurate value for the patient's actual V(T) is needed, this V(T) must be measured by a sensor located between the Y-piece and the tracheal tube.
Modelling and Simulation of Volume Controlled Mechanical Ventilation System
Yan Shi
2014-01-01
Full Text Available Volume controlled mechanical ventilation system is a typical time-delay system, which is applied to ventilate patients who cannot breathe adequately on their own. To illustrate the influences of key parameters of the ventilator on the dynamics of the ventilated respiratory system, this paper firstly derived a new mathematical model of the ventilation system; secondly, simulation and experimental results are compared to verify the mathematical model; lastly, the influences of key parameters of ventilator on the dynamics of the ventilated respiratory system are carried out. This study can be helpful in the VCV ventilation treatment and respiratory diagnostics.
Alternatives for Jet Engine Control. Volume 1: Modelling and Control Design with Jet Engine Data
Sain, M. K.
1985-01-01
This document compiles a comprehensive list of publications supported by, or related to, National Aeronautics and Space Administration Grant NSG-3048, entitled "Alternatives for Jet Engine Control". Dr. Kurt Seldner was the original Technical Officer for the grant, at Lewis Research Center. Dr. Bruce Lehtinen was the final Technical Officer. At the University of Notre Dame, Drs. Michael K. Sain and R. Jeffrey Leake were the original Project Directors, with Dr. Sain becoming the final Project Director. Publications cover work over a ten-year period. The Final Report is divided into two parts. Volume i, "Modelling and Control Design with Jet Engine Data", follows in this report. Volume 2, "Modelling and Control Design with Tensors", has been bound separately.
Thorborg, Jesper
, however, is constituted by the implementation of the $J_2$ flow theory in the control volume method. To apply the control volume formulation on the process of hardening concrete viscoelastic stress-strain models has been examined in terms of various rheological models. The generalized 3D models are based...... on two different suggestions in the literature, that is compressible or incompressible behaviour of the viscos response in the dashpot element. Numerical implementation of the models has shown very good agreement with corresponding analytical solutions. The viscoelastic solid mechanical model is used...
Andersen, Stig Kildegård; Carlsen, Henrik; Thomsen, Per Grove
2006-01-01
We present an approach for modelling unsteady, primarily one-dimensional, compressible flow. The conservation laws for mass, energy, and momentum are applied to a staggered mesh of control volumes and loss mechanisms are included directly as extra terms. Heat transfer, flow friction, and multidim...... are presented. The capabilities of the approach are illustrated with an example solution and an experimental validation of a Stirling engine model....
Front tracking based modeling of the solid grain growth on the adaptive control volume grid
Seredyński, Mirosław; Łapka, Piotr
2017-07-01
The paper presents the micro-scale model of unconstrained solidification of the grain immersed in under-cooled liquid, based on the front tracking approach. For this length scale, the interface tracked through the domain is meant as the solid-liquid boundary. To prevent generation of huge meshes the energy transport equation is discretized on the adaptive control volume (c.v.) mesh. The coupling of dynamically changing mesh and moving front position is addressed. Preliminary results of simulation of a test case, the growth of single grain, are presented and discussed.
Control-volume-based model of the steam-water injector flow
Kwidziński, Roman
2010-03-01
The paper presents equations of a mathematical model to calculate flow parameters in characteristic cross-sections in the steam-water injector. In the model, component parts of the injector (steam nozzle, water nozzle, mixing chamber, condensation wave region, diffuser) are treated as a series of connected control volumes. At first, equations for the steam nozzle and water nozzle are written and solved for known flow parameters at the injector inlet. Next, the flow properties in two-phase flow comprising mixing chamber and condensation wave region are determined from mass, momentum and energy balance equations. Then, water compression in diffuser is taken into account to evaluate the flow parameters at the injector outlet. Irreversible losses due to friction, condensation and shock wave formation are taken into account for the flow in the steam nozzle. In two-phase flow domain, thermal and mechanical nonequilibrium between vapour and liquid is modelled. For diffuser, frictional pressure loss is considered. Comparison of the model predictions with experimental data shows good agreement, with an error not exceeding 15% for discharge (outlet) pressure and 1 K for outlet temperature.
Control volume based hydrocephalus research
Cohen, Benjamin; Voorhees, Abram; Wei, Timothy
2008-11-01
Hydrocephalus is a disease involving excess amounts of cerebral spinal fluid (CSF) in the brain. Recent research has shown correlations to pulsatility of blood flow through the brain. However, the problem to date has presented as too complex for much more than statistical analysis and understanding. This talk will highlight progress on developing a fundamental control volume approach to studying hydrocephalus. The specific goals are to select physiologically control volume(s), develop conservation equations along with the experimental capabilities to accurately quantify terms in those equations. To this end, an in vitro phantom is used as a simplified model of the human brain. The phantom's design consists of a rigid container filled with a compressible gel. The gel has a hollow spherical cavity representing a ventricle and a cylindrical passage representing the aquaducts. A computer controlled piston pump supplies pulsatile volume fluctuations into and out of the flow phantom. MRI is used to measure fluid velocity, and volume change as functions of time. Independent pressure measurements and flow rate measurements are used to calibrate the MRI data. These data are used as a framework for future work with live patients.
Stress strain modelling of casting processes in the framework of the control volume method
Hattel, Jesper; Andersen, Søren; Thorborg, Jesper
1998-01-01
Realistic computer simulations of casting processes call for the solution of both thermal, fluid-flow and stress/strain related problems. The multitude of the influencing parameters, and their non-linear, transient and temperature dependent nature, make the calculations complex. Therefore the nee......, the present model is based on the mainly decoupled representation of the thermal, mechanical and microstructural processes. Examples of industrial applications, such as predicting residual deformations in castings and stress levels in die casting dies, are presented...... for fast, flexible, multidimensional numerical methods is obvious. The basis of the deformation and stress/strain calculation is a transient heat transfer analysis including solidification. This paper presents an approach where the stress/strain and the heat transfer analysis uses the same computational...... domain, which is highly convenient. The basis of the method is the control volume finite difference approach on structured meshes. The basic assumptions of the method are shortly reviewed and discussed. As for other methods which aim at application oriented analysis of casting deformations and stresses...
Burgess, P. M.; Steel, R. J.
2016-12-01
control volume and trajectories constructed from outcrop analysis, subsurface analysis and experimental models may help the convergence, reconciliation and future evolution of these different approaches.
1978-05-01
The User Delay Cost Model (UDCM) is a Monte Carlo computer simulation of essential aspects of Terminal Control Area (TCA) air traffic movements that would be affected by facility outages. The model can also evaluate delay effects due to other factors...
Alloui, L., E-mail: lotfi.alloui@lgep.supelec.fr [Laboratoire de Genie Electrique de Paris - LGEP, CNRS UMR 8507, Supelec, Universite Pierre et Marie Curie-Paris 6, Universite Paris Sud-Paris 11, Plateau de Moulon, 11 rue Joliot Curie, 91192 Gif-Sur-Yvette Cedex (France); Laboratoire de modelisation des systemes energetiques (LMSE), Universite de Biskra, 07000 Biskra (Algeria); Bouillault, F., E-mail: bouillault@lgep.supelec.fr [Laboratoire de Genie Electrique de Paris - LGEP, CNRS UMR 8507, Supelec, Universite Pierre et Marie Curie-Paris 6, Universite Paris Sud-Paris 11, Plateau de Moulon, 11 rue Joliot Curie, 91192 Gif-Sur-Yvette Cedex (France); Bernard, L., E-mail: laurent.bernardl@lgep.supelc.fr [Laboratoire de Genie Electrique de Paris - LGEP, CNRS UMR 8507, Supelec, Universite Pierre et Marie Curie-Paris 6, Universite Paris Sud-Paris 11, Plateau de Moulon, 11 rue Joliot Curie, 91192 Gif-Sur-Yvette Cedex (France); Leveque, J., E-mail: jean.leveque@green.uhp-nancy.fr [Groupe de recherche en electronique et electrotechnique de Nancy, Universite Henry Poincare, BP 239, 54506 Vandoeuvre les Nancy (France)
2012-05-15
In this paper we present new 3D numerical model to calculate the vertical and the guidance forces in high temperature superconductors taking into account the influence of the flux creep phenomena. In the suggested numerical model, we adopt a new approach of the control volume method. This approach is based on the use of an unstructured grid which can be used to model more complex geometries. A comparison of the control volume method results with experiments verifies the validity of this approach and the proposed numerical model. Based on this model, the levitation force's relaxation at different temperatures was also studied.
Transaction-based building controls framework, Volume 2: Platform descriptive model and requirements
Akyol, Bora A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Haack, Jereme N. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Carpenter, Brandon J. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Lutes, Robert G. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hernandez, George [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
2015-07-31
Transaction-based Building Controls (TBC) offer a control systems platform that provides an agent execution environment that meets the growing requirements for security, resource utilization, and reliability. This report outlines the requirements for a platform to meet these needs and describes an illustrative/exemplary implementation.
The plant cytoskeleton controls regulatory volume increase.
Liu, Qiong; Qiao, Fei; Ismail, Ahmed; Chang, Xiaoli; Nick, Peter
2013-09-01
The ability to adjust cell volume is required for the adaptation to osmotic stress. Plant protoplasts can swell within seconds in response to hypoosmotic shock suggesting that membrane material is released from internal stores. Since the stability of plant membranes depends on submembraneous actin, we asked, whether this regulatory volume control depends on the cytoskeleton. As system we used two cell lines from grapevine which differ in their osmotic tolerance and observed that the cytoskeleton responded differently in these two cell lines. To quantify the ability for regulatory volume control, we used hydraulic conductivity (Lp) as readout and demonstrated a role of the cytoskeleton in protoplast swelling. Chelation of calcium, inhibition of calcium channels, or manipulation of membrane fluidity, did not significantly alter Lp, whereas direct manipulation of the cytoskeleton via specific chemical reagents, or indirectly, through the bacterial elicitor Harpin or activation of phospholipase D, was effective. By optochemical engineering of actin using a caged form of the phytohormone auxin we can break the symmetry of actin organisation resulting in a localised deformation of cell shape indicative of a locally increased Lp. We interpret our findings in terms of a model, where the submembraneous cytoskeleton controls the release of intracellular membrane stores during regulatory volume change. Copyright © 2013 Elsevier B.V. All rights reserved.
1978-05-01
The User Delay Cost Model (UDCM) is a Monte Carlo simulation of certain classes of movement of air traffic in the Boston Terminal Control Area (TCA). It incorporates a weather module, an aircraft generation module, a facilities module, and an air con...
Control volume based hydrocephalus research; analysis of human data
Cohen, Benjamin; Wei, Timothy; Voorhees, Abram; Madsen, Joseph; Anor, Tomer
2010-11-01
Hydrocephalus is a neuropathophysiological disorder primarily diagnosed by increased cerebrospinal fluid volume and pressure within the brain. To date, utilization of clinical measurements have been limited to understanding of the relative amplitude and timing of flow, volume and pressure waveforms; qualitative approaches without a clear framework for meaningful quantitative comparison. Pressure volume models and electric circuit analogs enforce volume conservation principles in terms of pressure. Control volume analysis, through the integral mass and momentum conservation equations, ensures that pressure and volume are accounted for using first principles fluid physics. This approach is able to directly incorporate the diverse measurements obtained by clinicians into a simple, direct and robust mechanics based framework. Clinical data obtained for analysis are discussed along with data processing techniques used to extract terms in the conservation equation. Control volume analysis provides a non-invasive, physics-based approach to extracting pressure information from magnetic resonance velocity data that cannot be measured directly by pressure instrumentation.
[Evaluation of tidal volume delivered by ventilators during volume-controlled ventilation].
Zhou, Juan; Yan, Yong; Cao, Desen
2014-12-01
To study the ways which ensure the delivery of enough tidal volume to patients under various conditions close to the demand of the physician. The volume control ventilation model was chosen, and the simulation lung type was active servo lung ASL 5000 or Michigan lung 1601. The air resistance, air compliance and lung type in simulation lungs were set. The tidal volume was obtained from flow analyzer PF 300. At the same tidal volume, the displaying values of tidal volume of E5, Servo i, Evital 4, and Evital XL ventilators with different lung types of patient, compliance of gas piping, leakage, gas types, etc. were evaluated. With the same setting tidal volume of a same ventilator, the tidal volume delivered to patients was different with different lung types of patient, compliance of gas piping, leakage, gas types, etc. Reducing compliance and increasing resistance of the patient lungs caused high peak airway pressure, the tidal volume was lost in gas piping, and the tidal volume be delivered to the patient lungs was decreased. If the ventilator did not compensate to leakage, the tidal volume delivered to the patient lungs was decreased. When the setting gas type of ventilator did not coincide with that applying to the patient, the tidal volume be delivered to the patient lungs might be different with the setting tidal volume of ventilator. To ensure the delivery of enough tidal volume to patients close to the demand of the physician, containable factors such as the compliance of gas piping, leakage, and gas types should be controlled.
1978-05-01
The Facilities Maintenance Cost Model (FMCM) is an analytic model designed to calculate expected annual labor costs of maintenance within a given FAA maintenance sector. The model is programmed in FORTRAN IV and has been demonstrated on the CDC Krono...
CAREM-25. Purification and volume control system
Acosta, Eduardo; Carlevaris, Rodolfo; Patrignani, Alberto; Chocron, Mauricio; Goya, Hector E.; Ortega, Daniel A.; Ramilo, Lucia B.
2000-01-01
The purification and volume control system has the following main functions: water level control inside reactor pressure vessel (RPR) in all the reactor operational modes, pressure control when the reactor operates in solid state, and maintenance of radiological, physical and chemical parameters of primary water. In case of Hot Shutdown operational mode and also after Scram the system is capable of extraction of nuclear decay heat. The design of the system is in accordance with the Requirements of ANSI/ ANS 51.1; 58.11 and 56.2 standards. (author)
Guldager, Henrik; Nielsen, Soeren L; Carl, Peder; Soerensen, Mogens B
1997-01-01
Background: The aim of this study was to test the hypothesis that a new mode of ventilation (pressure-regulated volume control; PRVC) is associated with improvements in respiratory mechanics and outcome when compared with conventional volume control (VC) ventilation in patients with acute respiratory failure. We conducted a randomised, prospective, open, cross over trial on 44 patients with acute respiratory failure in the general intensive care unit of a university hospital. After a stabiliz...
Hydrothermal analysis in engineering using control volume finite element method
Sheikholeslami, Mohsen
2015-01-01
Control volume finite element methods (CVFEM) bridge the gap between finite difference and finite element methods, using the advantages of both methods for simulation of multi-physics problems in complex geometries. In Hydrothermal Analysis in Engineering Using Control Volume Finite Element Method, CVFEM is covered in detail and applied to key areas of thermal engineering. Examples, exercises, and extensive references are used to show the use of the technique to model key engineering problems such as heat transfer in nanofluids (to enhance performance and compactness of energy systems),
Teaching Thermal Hydraulics & Numerical Methods: An Introductory Control Volume Primer
Lucas, D.S.
2004-10-03
This paper covers the basics of the implementation of the control volume method in the context of the Homogeneous Equilibrium Model (HEM)(T/H) code using the conservation equations of mass, momentum, and energy. This primer uses the advection equation as a template. The discussion will cover the basic equations of the control volume portion of the course in the primer, which includes the advection equation, numerical methods, along with the implementation of the various equations via FORTRAN into computer programs and the final result for a three equation HEM code and its validation.
International Nuclear Model. Volume 3. Program description
Andress, D.
1985-01-01
This is Volume 3 of three volumes of documentation of the International Nuclear Model (INM). This volume presents the Program Description of the International Nuclear Model, which was developed for the Nuclear and Alternate Fuels Division (NAFD), Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), US Department of Energy (DOE). The International Nuclear Model (INM) is a comprehensive model of the commercial nuclear power industry. It simulates economic decisions for reactor deployment and fuel management decision based on an input set of technical economic and scenario parameters. The technical parameters include reactor operating characteristics, fuel cycle timing and mass loss factors, and enrichment tails assays. Economic parameters include fuel cycle costs, financial data, and tax alternatives. INM has a broad range of scenario options covering, for example, process constraints, interregional activities, reprocessing, and fuel management selection. INM reports reactor deployment schedules, electricity generation, and fuel cycle requirements and costs. It also has specialized reports for extended burnup and permanent disposal. Companion volumes to Volume 3 are: Volume 1 - Model Overview, and Volume 2 - Data Base Relationships
Computational Model for Spacecraft/Habitat Volume
National Aeronautics and Space Administration — Please note that funding to Dr. Simon Hsiang, a critical co-investigator for the development of the Spacecraft Optimization Layout and Volume (SOLV) model, was...
An optimal control problem for controlling the cell volume in dehydration and rehydration process
Chenghung Huang; Tetsung Chen [National Cheng Kung Univ., Dept. of Systems and Naval Mechatronic Engineering, Tainan (Taiwan)
2004-08-01
An optimal control algorithm utilizing the conjugate gradient method (CGM) of minimization is applied successfully in the present study in determining the optimal boundary control function for a diffusion-limited cell model based on the desired cell volume. The validity of the present optimal control analysis is examined by means of numerical experiments. Different desired cell volume for dehydration, rehydration and their combination are given in three test cases with different weighting coefficients and the corresponding optimal control functions are determined. The results show that the optimal boundary control functions can be obtained with an arbitrary initial guess within one second CPU time on a Pentium III-600 MHz PC. (Author)
Control volume based hydrocephalus research; a phantom study
Cohen, Benjamin; Voorhees, Abram; Madsen, Joseph; Wei, Timothy
2009-11-01
Hydrocephalus is a complex spectrum of neurophysiological disorders involving perturbation of the intracranial contents; primarily increased intraventricular cerebrospinal fluid (CSF) volume and intracranial pressure are observed. CSF dynamics are highly coupled to the cerebral blood flows and pressures as well as the mechanical properties of the brain. Hydrocephalus, as such, is a very complex biological problem. We propose integral control volume analysis as a method of tracking these important interactions using mass and momentum conservation principles. As a first step in applying this methodology in humans, an in vitro phantom is used as a simplified model of the intracranial space. The phantom's design consists of a rigid container filled with a compressible gel. Within the gel a hollow spherical cavity represents the ventricular system and a cylindrical passage represents the spinal canal. A computer controlled piston pump supplies sinusoidal volume fluctuations into and out of the flow phantom. MRI is used to measure fluid velocity and volume change as functions of time. Independent pressure measurements and momentum flow rate measurements are used to calibrate the MRI data. These data are used as a framework for future work with live patients and normal individuals. Flow and pressure measurements on the flow phantom will be presented through the control volume framework.
Magmatic densities control erupted volumes in Icelandic volcanic systems
Hartley, Margaret; Maclennan, John
2018-04-01
Magmatic density and viscosity exert fundamental controls on the eruptibility of magmas. In this study, we investigate the extent to which magmatic physical properties control the eruptibility of magmas from Iceland's Northern Volcanic Zone (NVZ). By studying subaerial flows of known age and volume, we are able to directly relate erupted volumes to magmatic physical properties, a task that has been near-impossible when dealing with submarine samples dredged from mid-ocean ridges. We find a strong correlation between magmatic density and observed erupted volumes on the NVZ. Over 85% of the total volume of erupted material lies close to a density and viscosity minimum that corresponds to the composition of basalts at the arrival of plagioclase on the liquidus. These magmas are buoyant with respect to the Icelandic upper crust. However, a number of small-volume eruptions with densities greater than typical Icelandic upper crust are also found in Iceland's neovolcanic zones. We use a simple numerical model to demonstrate that the eruption of magmas with higher densities and viscosities is facilitated by the generation of overpressure in magma chambers in the lower crust and uppermost mantle. This conclusion is in agreement with petrological constraints on the depths of crystallisation under Iceland.
Magmatic Densities Control Erupted Volumes in Icelandic Volcanic Systems
Margaret Hartley
2018-04-01
Full Text Available Magmatic density and viscosity exert fundamental controls on the eruptibility of magmas. In this study, we investigate the extent to which magmatic physical properties control the eruptibility of magmas from Iceland's Northern Volcanic Zone (NVZ. By studying subaerial flows of known age and volume, we are able to directly relate erupted volumes to magmatic physical properties, a task that has been near-impossible when dealing with submarine samples dredged from mid-ocean ridges. We find a strong correlation between magmatic density and observed erupted volumes on the NVZ. Over 85% of the total volume of erupted material lies close to a density and viscosity minimum that corresponds to the composition of basalts at the arrival of plagioclase on the liquidus. These magmas are buoyant with respect to the Icelandic upper crust. However, a number of small-volume eruptions with densities greater than typical Icelandic upper crust are also found in Iceland's neovolcanic zones. We use a simple numerical model to demonstrate that the eruption of magmas with higher densities and viscosities is facilitated by the generation of overpressure in magma chambers in the lower crust and uppermost mantle. This conclusion is in agreement with petrological constraints on the depths of crystallization under Iceland.
Image registration with auto-mapped control volumes
Schreibmann, Eduard; Xing Lei
2006-01-01
Many image registration algorithms rely on the use of homologous control points on the two input image sets to be registered. In reality, the interactive identification of the control points on both images is tedious, difficult, and often a source of error. We propose a two-step algorithm to automatically identify homologous regions that are used as a priori information during the image registration procedure. First, a number of small control volumes having distinct anatomical features are identified on the model image in a somewhat arbitrary fashion. Instead of attempting to find their correspondences in the reference image through user interaction, in the proposed method, each of the control regions is mapped to the corresponding part of the reference image by using an automated image registration algorithm. A normalized cross-correlation (NCC) function or mutual information was used as the auto-mapping metric and a limited memory Broyden-Fletcher-Goldfarb-Shanno algorithm (L-BFGS) was employed to optimize the function to find the optimal mapping. For rigid registration, the transformation parameters of the system are obtained by averaging that derived from the individual control volumes. In our deformable calculation, the mapped control volumes are treated as the nodes or control points with known positions on the two images. If the number of control volumes is not enough to cover the whole image to be registered, additional nodes are placed on the model image and then located on the reference image in a manner similar to the conventional BSpline deformable calculation. For deformable registration, the established correspondence by the auto-mapped control volumes provides valuable guidance for the registration calculation and greatly reduces the dimensionality of the problem. The performance of the two-step registrations was applied to three rigid registration cases (two PET-CT registrations and a brain MRI-CT registration) and one deformable registration of
Modeling the economics of LLW volume reduction
Voth, M.H.; Witzig, W.F.
1986-01-01
Generators of low-level (radioactive) waste (LLW) are under pressure to implement volume reduction (VR) programs for political and economic reasons. Political reasons include the appearance of generating less waste or meeting quotas. Economic reasons include avoiding high disposal costs and associated surcharges. Volume reduction results in less total volume over which fixed disposal costs are allocated and therefore higher unit costs for disposal. As numerous small compacts are developed, this often overlooked effect becomes more pronounced. The described model presents two unique significant features. First, a feedback loop considers the impact of VR on disposal rates, and second, it appeals to logic without extensive knowledge of VR technology or computer modeling. The latter feature is especially useful in conveying information to students and nontechnical decision makers, demonstrating the impact of each of a complicated set of variables with reproducible results
EARTHWORK VOLUME CALCULATION FROM DIGITAL TERRAIN MODELS
JANIĆ Milorad
2015-06-01
Full Text Available Accurate calculation of cut and fill volume has an essential importance in many fields. This article shows a new method, which has no approximation, based on Digital Terrain Models. A relatively new mathematical model is developed for that purpose, which is implemented in the software solution. Both of them has been tested and verified in the praxis on several large opencast mines. This application is developed in AutoLISP programming language and works in AutoCAD environment.
Biological modelling of fuzzy target volumes in 3D radiotherapy
Levegruen, S.; Kampen, M. van; Waschek, T.; Engenhart, R.; Schlegel, W.
1995-01-01
Purpose/Objective: The outcome of each radiotherapy depends critically on the optimal choice of the target volume. The goal of the radiotherapist is to include all tumor spread at the same time as saving as much healthy tissue as possible. Even when the information of all imaging modalities is combined, the diagnostic techniques are not sensitive and specific enough to visualize all microscopic tumor cell spread. Due to this lack of information there is room for different interpretations concerning the extend of the target volume, leading to a fuzzy target volume. The aim of this work is to develop a model to score different target volume boundaries within the region of diagnostic uncertainty in terms of tumor control probability (TCP) and normal tissue complication probabilities (NTCP). Materials and Methods: In order to assess the region of diagnostic uncertainty, the radiotherapist defines interactively a minimal planning target volume that absolutely must be irradiated according to the diagnostic information available and a maximal planning target volume outside which no tumor cell spread is expected. For the NTCP calculation we use the Lyman 4 parameter model to estimate the response of an organ at risk to a uniform partial volume irradiation. The TCP calculation is based on the Poisson model of cell killing. The TCP estimation depends not only on volume, dose, clonogenic cell density and the α parameter of the linear quadratic model but also on the probability to find clonogenic cells in the considered volume. Inside the minimal PTV this probability is 1, outside the maximal PTV it is 0. Therefore all voxels inside the minimal PTV are assigned the value of 1 with respect to the target volume, all voxels outside the maximal PTV the value of 0. For voxels in the region of uncertainty in between, a 3D linear interpolation is performed. Here we assume the probability to follow the interpolated values. Starting with the minimal PTV, the expected gain in TCP and
1988 DOE model conference proceedings: Volume 4
1988-01-01
These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 4 include site characterization and remediation projects, environmental monitoring and modeling; disposal site selection and facility design, risk assessment, safety and health issues, and site remediation technology
1988 DOE model conference proceedings: Volume 4
1988-01-01
These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 4 include site characterization and remediation projects, environmental monitoring and modeling; disposal site selection and facility design, risk assessment, safety and health issues, and site remediation technology.
Cardiovascular and fluid volume control in humans in space
Norsk, Peter
2005-01-01
on this complex interaction, because it is the only way to completely abolish the effects of gravity over longer periods. Results from space have been unexpected, because astronauts exhibit a fluid and sodium retaining state with activation of the sympathetic nervous system, which subjects during simulations...... by head-down bed rest do not. Therefore, the concept as to how weightlessness affects the cardiovascular system and modulates regulation of body fluids should be revised and new simulation models developed. Knowledge as to how gravity and weightlessness modulate integrated fluid volume control...
Effects of uncertainty in model predictions of individual tree volume on large area volume estimates
Ronald E. McRoberts; James A. Westfall
2014-01-01
Forest inventory estimates of tree volume for large areas are typically calculated by adding model predictions of volumes for individual trees. However, the uncertainty in the model predictions is generally ignored with the result that the precision of the large area volume estimates is overestimated. The primary study objective was to estimate the effects of model...
Bachiller, Patricia R; McDonough, Joseph M; Feldman, Jeffrey M
2008-05-01
During mechanical ventilation of infants and neonates, small changes in tidal volume may lead to hypo- or hyperventilation, barotrauma, or volutrauma. Partly because breathing circuit compliance and fresh gas flow affect tidal volume delivery by traditional anesthesia ventilators in volume-controlled ventilation (VCV) mode, pressure-controlled ventilation (PCV) using a circle breathing system has become a common approach to minimizing the risk of mechanical ventilation for small patients, although delivered tidal volume is not assured during PCV. A new generation of anesthesia machine ventilators addresses the problems of VCV by adjusting for fresh gas flow and for the compliance of the breathing circuit. In this study, we evaluated the accuracy of new anesthesia ventilators to deliver small tidal volumes. Four anesthesia ventilator systems were evaluated to determine the accuracy of volume delivery to the airway during VCV at tidal volume settings of 100, 200, and 500 mL under different conditions of breathing circuit compliance (fully extended and fully contracted circuits) and lung compliance. A mechanical test lung (adult and infant) was used to simulate lung compliances ranging from 0.0025 to 0.03 L/cm H(2)O. Volumes and pressures were measured using a calibrated screen pneumotachograph and custom software. We tested the Smartvent 7900, Avance, and Aisys anesthesia ventilator systems (GE Healthcare, Madison, WI) and the Apollo anesthesia ventilator (Draeger Medical, Telford, PA). The Smartvent 7900 and Avance ventilators use inspiratory flow sensors to control the volume delivered, whereas the Aisys and Apollo ventilators compensate for the compliance of the circuit. We found that the anesthesia ventilators that use compliance compensation (Aisys and Apollo) accurately delivered both large and small tidal volumes to the airway of the test lung under conditions of normal and low lung compliance during VCV (ranging from 95.5% to 106.2% of the set tidal volume
Guldager, Henrik; Nielsen, Soeren L; Carl, Peder; Soerensen, Mogens B
1997-01-01
Background: The aim of this study was to test the hypothesis that a new mode of ventilation (pressure-regulated volume control; PRVC) is associated with improvements in respiratory mechanics and outcome when compared with conventional volume control (VC) ventilation in patients with acute respiratory failure. We conducted a randomised, prospective, open, cross over trial on 44 patients with acute respiratory failure in the general intensive care unit of a university hospital. After a stabilization period of 8 h, a cross over trial of 2 × 2 h was conducted. Apart from the PRVC/VC mode, ventilator settings were comparable. The following parameters were recorded for each patient: days on ventilator, failure in the assigned mode of ventilation (peak inspiratory pressure > 50 cmH2O) and survival. Results: In the crossover trial, peak inspiratory pressure was significantly lower using PRVC than with VC (20 cmH2O vs 24 cmH2O, P < 0.0001). No other statistically significant differences were found. Conclusions: Peak inspiratory pressure was significantly lower during PRVC ventilation than during VC ventilation, and thus PRVC may be superior to VC in certain patients. However, in this small group of patients, we could not demonstrate that PRVC improved outcome. PMID:11056699
Stochastic models, estimation, and control
Maybeck, Peter S
1982-01-01
This volume builds upon the foundations set in Volumes 1 and 2. Chapter 13 introduces the basic concepts of stochastic control and dynamic programming as the fundamental means of synthesizing optimal stochastic control laws.
1988 DOE model conference proceedings: Volume 2
1988-01-01
These Proceedings of the October 3 - 7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Volume 2 contains information on environmental restoration at federal facilities, waste disposal technology, quality assurance, contingency planning and emergency response, decontamination and decommissioning, environmental restoration, and public involvement in waste management
1988 DOE model conference proceedings: Volume 5
1988-01-01
These Proceedings of the October 3--7, 1988 DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 5 include environmental assessments and program strategies, waste treatment technologies, and regulations and compliance studies.
1988 DOE model conference proceedings: Volume 1
1988-01-01
These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics included in Volume 1 are Environmental Data Management, Site characterization technology, Wastewater treatment, Waste management in foreign countries, Transuranic waste management, and Groundwater characterization and treatment
1988 DOE model conference proceedings: Volume 3
1988-01-01
These Proceedings of the October 3 - 7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics included in Volume 3 include treatment of soils, waste characterization and certification, waste minimization site remediation management plans and programs, and training programs
1988 DOE model conference proceedings: Volume 1
1988-01-01
These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics included in Volume 1 are Environmental Data Management, Site characterization technology, Wastewater treatment, Waste management in foreign countries, Transuranic waste management, and Groundwater characterization and treatment.
1988 DOE model conference proceedings: Volume 5
1988-01-01
These Proceedings of the October 3--7, 1988 DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 5 include environmental assessments and program strategies, waste treatment technologies, and regulations and compliance studies
Airborne radioactive emission control technology. Volume II
Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.
1980-03-01
This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, including uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking, a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented
Airborne radioactive emission control technology. Volume III
Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.
1980-03-01
This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, including uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking, a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented
Airborne radioactive emission control technology. Volume I
Skoski, L.; Berlin, R.; Corby, D.; Clancy, J.; Hoopes, G.
1980-03-01
This report reviews the current and future control technology for airborne emissions from a wide variety of industries/facilities, includimg uranium mining and milling, other nuclear fuel cycle facilities, other NRC-licensed and DOE facilities, fossil fuel facilities, selected metal and non-metal extraction industries, and others. Where specific radioactivity control technology is lacking a description of any existing control technology is given. Future control technology is assessed in terms of improvements to equipment performance and process alterations. A catalogue of investigated research on advanced control technologies is presented
Design method for marine direct drive volume control ahead actuator
WANG Haiyang
2018-02-01
Full Text Available [Objectives] In order to reduce the size, weight and auxiliary system configuration of marine ahead actuators, this paper proposes a kind of direct drive volume control electro-hydraulic servo ahead actuator. [Methods] The protruding and indenting control of the servo oil cylinder are realized through the forward and reverse of the bidirectional working gear pump, and the flow matching valve implements the self-locking of the ahead actuator in the target position. The mathematical model of the ahead actuator is established, and an integral separation fuzzy PID controller designed. On this basis, using AMESim software to build a simulation model of the ahead actuator, and combined with testing, this paper completes an analysis of the control strategy research and dynamic and static performance of the ahead actuator. [Results] The experimental results agree well with the simulation results and verify the feasibility of the ahead actuator's design. [Conclusions] The research results of this paper can provide valuable references for the integration and miniaturization design of marine ahead actuators.
Teaching Thermal Hydraulics & Numerical Methods: An Introductory Control Volume Primer
D. S. Lucas
2004-10-01
A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.com.
Control-Volume Analysis Of Thrust-Augmenting Ejectors
Drummond, Colin K.
1990-01-01
New method of analysis of transient flow in thrust-augmenting ejector based on control-volume formulation of governing equations. Considered as potential elements of propulsion subsystems of short-takeoff/vertical-landing airplanes.
Fuzzy Control of Tidal volume, Respiration number and Pressure value
Hasan Guler; Fikret Ata
2010-01-01
In this study, control of tidal volume, respiration number and pressure value which are arrived to patient at mechanical ventilator device which is used in intensive care units were performed with fuzzy logic controller. The aim of this system is to reduce workload of aneshesiologist. By calculating tidal volume, respiration number and pressure value, the error Pe(k) between reference pressure value (Pref) and pressure of gas given ill person (Phasta) and error change rate ;#948;Pe(k) were co...
A Computational Model of Hydraulic Volume Displacement Drive
V. N. Pil'gunov
2014-01-01
Full Text Available The paper offers a computational model of industrial-purpose hydraulic drive with two hydraulic volume adjustable working chamber machines (pump and motor. Adjustable pump equipped with the pressure control unit can be run together with several adjustable hydraulic motors on the principle of three-phase hydraulic socket-outlet with high-pressure lines, drain, and drainage system. The paper considers the pressure-controlled hydrostatic transmission with hydraulic motor as an output link. It shows a possibility to create a saving hydraulic drive using a functional tie between the adjusting parameters of the pump and hydraulic motor through the pressure difference, torque, and angular rate of the hydraulic motor shaft rotation. The programmable logic controller can implement such tie. The Coulomb and viscous frictions are taken into consideration when developing a computational model of the hydraulic volume displacement drive. Discharge balance considers external and internal leakages in equivalent clearances of hydraulic machines, as well as compression loss volume caused by hydraulic fluid compressibility and deformation of pipe walls. To correct dynamic properties of hydraulic drive, the paper offers that in discharge balance are included the additional regulated external leakages in the open circuit of hydraulic drive and regulated internal leakages in the closed-loop circuit. Generalized differential equations having functional multipliers and multilinked nature have been obtained to describe the operation of hydraulic positioning and speed drive with two hydraulic volume adjustable working chamber machines. It is shown that a proposed computational model of hydraulic drive can be taken into consideration in development of LS («Load-Sensing» drives, in which the pumping pressure is tuned to the value required for the most loaded slave motor to overcome the load. Results attained can be used both in designing the industrial-purpose heavy
Neutron behavior, reactor control, and reactor heat transfer. Volume four
Anon.
1986-01-01
Volume four covers neutron behavior (neutron absorption, how big are nuclei, neutron slowing down, neutron losses, the self-sustaining reactor), reactor control (what is controlled in a reactor, controlling neutron population, is it easy to control a reactor, range of reactor control, what happens when the fuel burns up, controlling a PWR, controlling a BWR, inherent safety of reactors), and reactor heat transfer (heat generation in a nuclear reactor, how is heat removed from a reactor core, heat transfer rate, heat transfer properties of the reactor coolant)
Stem biomass and volume models of selected tropical tree species ...
Stem biomass and stem volume were modelled as a function of diameter (at breast height; Dbh) and stem height (height to the crown base). Logarithmic models are presented that utilise Dbh and height data to predict tree component biomass and stem volumes. Alternative models are given that afford prediction based on ...
The order and volume fill rates in inventory control systems
Thorstenson, Anders; Larsen, Christian
2011-01-01
This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level...... measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...
Lyazidi, Aissam; Thille, Arnaud W; Carteaux, Guillaume; Galia, Fabrice; Brochard, Laurent; Richard, Jean-Christophe M
2010-12-01
During volume-controlled ventilation, part of the volume delivered is compressed into the circuit. To correct for this phenomenon, modern ventilators use compensation algorithms. Humidity and temperature also influence the delivered volume. In a bench study at a research laboratory in a university hospital, we compared nine ICU ventilators equipped with compensation algorithms, one with a proximal pneumotachograph and one without compensation. Each ventilator was evaluated under normal, obstructive, and restrictive conditions of respiratory mechanics. For each condition, three tidal volumes (V (T)) were set (300, 500, and 800 ml), with and without an inspiratory pause. The insufflated volume and the volume delivered at the Y-piece were measured independently, without a humidification device, under ambient temperature and pressure and dry gas conditions. We computed the actually delivered V (T) to the lung under body temperature and pressure and saturated water vapour conditions (BTPS). For target V (T) values of 300, 500, and 800 ml, actually delivered V (T) under BTPS conditions ranged from 261 to 396 ml (-13 to +32%), from 437 to 622 ml (-13 to +24%), and from 681 to 953 ml (-15 to +19%), respectively (p ventilators.
Future Communication, Computing, Control and Management Volume 2
2012-01-01
This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.
Future Communication, Computing, Control and Management Volume 1
2012-01-01
This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.
Future Computing, Communication, Control and Management Volume 2
2012-01-01
This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.
Bressan, Alberto; Lewicka, Marta
2018-03-01
We consider a free boundary problem for a system of PDEs, modeling the growth of a biological tissue. A morphogen, controlling volume growth, is produced by specific cells and then diffused and absorbed throughout the domain. The geometric shape of the growing tissue is determined by the instantaneous minimization of an elastic deformation energy, subject to a constraint on the volumetric growth. For an initial domain with C}^{2,α boundary, our main result establishes the local existence and uniqueness of a classical solution, up to a rigid motion.
High call volume at poison control centers: identification and implications for communication.
Caravati, E M; Latimer, S; Reblin, M; Bennett, H K W; Cummins, M R; Crouch, B I; Ellington, L
2012-09-01
High volume surges in health care are uncommon and unpredictable events. Their impact on health system performance and capacity is difficult to study. To identify time periods that exhibited very busy conditions at a poison control center and to determine whether cases and communication during high volume call periods are different from cases during low volume periods. Call data from a US poison control center over twelve consecutive months was collected via a call logger and an electronic case database (Toxicall®).Variables evaluated for high call volume conditions were: (1) call duration; (2) number of cases; and (3) number of calls per staff member per 30 minute period. Statistical analyses identified peak periods as busier than 99% of all other 30 minute time periods and low volume periods as slower than 70% of all other 30 minute periods. Case and communication characteristics of high volume and low volume calls were compared using logistic regression. A total of 65,364 incoming calls occurred over 12 months. One hundred high call volume and 4885 low call volume 30 minute periods were identified. High volume periods were more common between 1500 and 2300 hours and during the winter months. Coded verbal communication data were evaluated for 42 high volume and 296 low volume calls. The mean (standard deviation) call length of these calls during high volume and low volume periods was 3 minutes 27 seconds (1 minute 46 seconds) and 3 minutes 57 seconds (2 minutes 11 seconds), respectively. Regression analyses revealed a trend for fewer overall verbal statements and fewer staff questions during peak periods, but no other significant differences for staff-caller communication behaviors were found. Peak activity for poison center call volume can be identified by statistical modeling. Calls during high volume periods were similar to low volume calls. Communication was more concise yet staff was able to maintain a good rapport with callers during busy call periods
Model Process Control Language
National Aeronautics and Space Administration — The MPC (Model Process Control) language enables the capture, communication and preservation of a simulation instance, with sufficient detail that it can be...
The order and volume fill rates in inventory control systems
Thorstenson, Anders; Larsen, Christian
2011-01-01
This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level m...
Siegel, A.I.; Bartter, W.D.; Wolf, J.J.; Knee, H.E.
1984-12-01
This volume of NUREG/CR-3626 presents details of the content, structure, and sensitivity testing of the Maintenance Personnel Performance Simulation (MAPPS) model that was described in summary in volume one of this report. The MAPPS model is a generalized stochastic computer simulation model developed to simulate the performance of maintenance personnel in nuclear power plants. The MAPPS model considers workplace, maintenance technician, motivation, human factors, and task oriented variables to yield predictive information about the effects of these variables on successful maintenance task performance. All major model variables are discussed in detail and their implementation and interactive effects are outlined. The model was examined for disqualifying defects from a number of viewpoints, including sensitivity testing. This examination led to the identification of some minor recalibration efforts which were carried out. These positive results indicate that MAPPS is ready for initial and controlled applications which are in conformity with its purposes
Wallon, G; Bonnet, A; Guérin, C
2013-06-01
Tidal volume (V(T)) must be accurately delivered by anaesthesia ventilators in the volume-controlled ventilation mode in order for lung protective ventilation to be effective. However, the impact of fresh gas flow (FGF) and lung mechanics on delivery of V(T) by the newest anaesthesia ventilators has not been reported. We measured delivered V(T) (V(TI)) from four anaesthesia ventilators (Aisys™, Flow-i™, Primus™, and Zeus™) on a pneumatic test lung set with three combinations of lung compliance (C, ml cm H2O(-1)) and resistance (R, cm H2O litre(-1) s(-2)): C60R5, C30R5, C60R20. For each CR, three FGF rates (0.5, 3, 10 litre min(-1)) were investigated at three set V(T)s (300, 500, 800 ml) and two values of PEEP (0 and 10 cm H2O). The volume error = [(V(TI) - V(Tset))/V(Tset)] ×100 was computed in body temperature and pressure-saturated conditions and compared using analysis of variance. For each CR and each set V(T), the absolute value of the volume error significantly declined from Aisys™ to Flow-i™, Zeus™, and Primus™. For C60R5, these values were 12.5% for Aisys™, 5% for Flow-i™ and Zeus™, and 0% for Primus™. With an increase in FGF, absolute values of the volume error increased only for Aisys™ and Zeus™. However, in C30R5, the volume error was minimal at mid-FGF for Aisys™. The results were similar at PEEP 10 cm H2O. Under experimental conditions, the volume error differed significantly between the four new anaesthesia ventilators tested and was influenced by FGF, although this effect may not be clinically relevant.
Total tree, merchantable stem and branch volume models for ...
Total tree, merchantable stem and branch volume models for miombo woodlands of Malawi. Daud J Kachamba, Tron Eid. Abstract. The objective of this study was to develop general (multispecies) models for prediction of total tree, merchantable stem and branch volume including options with diameter at breast height (dbh) ...
The System 80+ Standard Plant design control document. Volume 17
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains parts 2-7 and appendix 15A for section 15 (Accident Analysis) of the ADM Design and Analysis. Topics covered in these parts are: decrease in heat removal; decrease in RCS flow rate; power distribution anomalies; increase in RCS inventory; decrease in RCS inventory; release of radioactive materials. The appendix covers radiological release models. Also contained here are five technical specifications for section 16 (Technical Specifications) of the ADM Design and Analysis. They are: TS 1.0 Use and Applications; TS 2.0 Safety Limits; TS 3.0 LCO Availability; TS 3.1 Reactivity Control; and TS 3.2 Power Distribution
Stochastic Control - External Models
Poulsen, Niels Kjølstad
2005-01-01
This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...
Aeroservoelasticity modeling and control
Tewari, Ashish
2015-01-01
This monograph presents the state of the art in aeroservoelastic (ASE) modeling and analysis and develops a systematic theoretical and computational framework for use by researchers and practicing engineers. It is the first book to focus on the mathematical modeling of structural dynamics, unsteady aerodynamics, and control systems to evolve a generic procedure to be applied for ASE synthesis. Existing robust, nonlinear, and adaptive control methodology is applied and extended to some interesting ASE problems, such as transonic flutter and buffet, post-stall buffet and maneuvers, and flapping flexible wing. The author derives a general aeroservoelastic plant via the finite-element structural dynamic model, unsteady aerodynamic models for various regimes in the frequency domain, and the associated state-space model by rational function approximations. For more advanced models, the full-potential, Euler, and Navier-Stokes methods for treating transonic and separated flows are also briefly addressed. Essential A...
RELAP5/MOD3 code manual. Volume 4, Models and correlations
1995-08-01
The RELAP5 code has been developed for best-estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents and operational transients such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I presents modeling theory and associated numerical schemes; Volume II details instructions for code application and input data preparation; Volume III presents the results of developmental assessment cases that demonstrate and verify the models used in the code; Volume IV discusses in detail RELAP5 models and correlations; Volume V presents guidelines that have evolved over the past several years through the use of the RELAP5 code; Volume VI discusses the numerical scheme used in RELAP5; and Volume VII presents a collection of independent assessment calculations
Klaus-Dietrich Kramer
2016-05-01
Full Text Available Many degree courses at technical universities include the subject of control systems engineering. As an addition to conventional approaches Fuzzy Control can be used to easily find control solutions for systems, even if they include nonlinearities. To support further educational training, models which represent a technical system to be controlled are required. These models have to represent the system in a transparent and easy cognizable manner. Furthermore, a programming tool is required that supports an easy Fuzzy Control development process, including the option to verify the results and tune the system behavior. In order to support the development process a graphical user interface is needed to display the fuzzy terms under real time conditions, especially with a debug system and trace functionality. The experiences with such a programming tool, the Fuzzy Control Design Tool (FHFCE Tool, and four fuzzy teaching models will be presented in this paper. The methodical and didactical objective in the utilization of these teaching models is to develop solution strategies using Computational Intelligence (CI applications for Fuzzy Controllers in order to analyze different algorithms of inference or defuzzyfication and to verify and tune those systems efficiently.
Cangioli, Filippo; Pennacchi, Paolo; Vannini, Giuseppe; Ciuchicchi, Lorenzo
2018-01-01
The influence of sealing components on the rotordynamic stability of turbomachinery has become a key topic because the oil and gas market is increasingly demanding high rotational speeds and high efficiency. This leads the turbomachinery manufacturers to design higher flexibility ratios and to reduce the clearance of the seals. Accurate prediction of the effective damping of seals is critical to avoid instability problems; in recent years, "negative-swirl" swirl brakes have been used to reverse the circumferential direction of the inlet flow, which changes the sign of the cross-coupled stiffness coefficients and generates stabilizing forces. Experimental tests for a teeth-on-stator labyrinth seal were performed by manufacturers with positive and negative pre-swirl values to investigate the pre-swirl effect on the cross-coupled stiffness coefficient. Those results are used as a benchmark in this paper. To analyse the rotor-fluid interaction in the seals, the bulk-flow numeric approach is more time efficient than computational fluid dynamics (CFD). Although the accuracy of the coefficients prediction in bulk-flow models is satisfactory for liquid phase application, the accuracy of the results strongly depends on the operating conditions in the case of the gas phase. In this paper, the authors propose an improvement in the state-of-the-art bulk-flow model by introducing the effect of the energy equation in the zeroth-order solution to better characterize real gas properties due to the enthalpy variation along the seal cavities. The consideration of the energy equation allows for a better estimation of the coefficients in the case of a negative pre-swirl ratio, therefore, it extend the prediction fidelity over a wide range of operating conditions. The numeric results are also compared to the state-of-the-art bulk-flow model, which highlights the improvement in the model.
The order and volume fill rates in inventory control systems
Thorstenson, Anders; Larsen, Christian
2014-01-01
This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total demanded quantity the order fill rate would be the preferred service...... level measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...... extensions consider more general inventory control review policies with backordering, as well as some relations between service measures. A particularly important result in the paper concerns an alternative service measure, the customer order fill rate, and shows how this measure always exceeds the other two...
Anon.
1993-01-01
Volume 1 contains the proceedings from three symposia. Contamination Control includes the following topics: Atmospheric pressure ionization mass spectroscopy (APIMS) applications; APIMS development; contamination control in cleanroom air; defect reduction in semiconductor processes; contamination control in the aerospace industry; filtration of gases; ultrapure chemical and DI water; filtration of chemicals; wafer cleaning/trace contaminant effects; wafer cleaning techniques; detection of particles in UHP fluids; detection of surface particles; modeling contamination; detection of surface organics; modeling, particle transport, deposition, and removal; and detection of surface metallics. Symposium on Minienvironments includes the following: design of minienvironments; robotics and I/O transport; testing, methods, and standards. The Symposium on Biocontamination Control includes the following: microbial CC facility requirements in pharmaceutical, biological, and medical device manufacture; cleaning and disinfecting methods and devices for bio CC; biocontamination control devices, methodology, and standards, airborne and surface microbial monitoring methods and devices; and regulatory issues in bio CC--present and future. All papers within the scope of the Energy Data Base have been processed separately for inclusion on the data base
Fliess, Michel; Join, Cédric
2013-12-01
'Model-free control'and the corresponding 'intelligent' PID controllers (iPIDs), which already had many successful concrete applications, are presented here for the first time in an unified manner, where the new advances are taken into account. The basics of model-free control is now employing some old functional analysis and some elementary differential algebra. The estimation techniques become quite straightforward via a recent online parameter identification approach. The importance of iPIs and especially of iPs is deduced from the presence of friction. The strange industrial ubiquity of classic PIDs and the great difficulty for tuning them in complex situations is deduced, via an elementary sampling, from their connections with iPIDs. Several numerical simulations are presented which include some infinite-dimensional systems. They demonstrate not only the power of our intelligent controllers but also the great simplicity for tuning them.
1987 Oak Ridge model conference: Proceedings: Volume 2, Environmental protection
1987-01-01
See the abstract for Volume I for general information on the conference. Topics discussed in Volume II include data management techiques for environmental protection efforts, the use of models in environmental auditing, in emergency plans, chemical accident emergency response, risk assessment, monitoring of waste sites, air and water monitoring of waste sites, and in training programs
1987 Oak Ridge model conference: Proceedings: Volume 2, Environmental protection
1987-01-01
See the abstract for Volume I for general information on the conference. Topics discussed in Volume II include data management techiques for environmental protection efforts, the use of models in environmental auditing, in emergency plans, chemical accident emergency response, risk assessment, monitoring of waste sites, air and water monitoring of waste sites, and in training programs. (TEM)
Disc volume reduction with percutaneous nucleoplasty in an animal model.
Richard Kasch
Full Text Available STUDY DESIGN: We assessed volume following nucleoplasty disc decompression in lower lumbar spines from cadaveric pigs using 7.1Tesla magnetic resonance imaging (MRI. PURPOSE: To investigate coblation-induced volume reductions as a possible mechanism underlying nucleoplasty. METHODS: We assessed volume following nucleoplastic disc decompression in pig spines using 7.1-Tesla MRI. Volumetry was performed in lumbar discs of 21 postmortem pigs. A preoperative image data set was obtained, volume was determined, and either disc decompression or placebo therapy was performed in a randomized manner. Group 1 (nucleoplasty group was treated according to the usual nucleoplasty protocol with coblation current applied to 6 channels for 10 seconds each in an application field of 360°; in group 2 (placebo group the same procedure was performed but without coblation current. After the procedure, a second data set was generated and volumes calculated and matched with the preoperative measurements in a blinded manner. To analyze the effectiveness of nucleoplasty, volumes between treatment and placebo groups were compared. RESULTS: The average preoperative nucleus volume was 0.994 ml (SD: 0.298 ml. In the nucleoplasty group (n = 21 volume was reduced by an average of 0.087 ml (SD: 0.110 ml or 7.14%. In the placebo group (n = 21 volume was increased by an average of 0.075 ml (SD: 0.075 ml or 8.94%. The average nucleoplasty-induced volume reduction was 0.162 ml (SD: 0.124 ml or 16.08%. Volume reduction in lumbar discs was significant in favor of the nucleoplasty group (p<0.0001. CONCLUSIONS: Our study demonstrates that nucleoplasty has a volume-reducing effect on the lumbar nucleus pulposus in an animal model. Furthermore, we show the volume reduction to be a coblation effect of nucleoplasty in porcine discs.
Guidance and Control Software Project Data - Volume 2: Development Documents
Hayhurst, Kelly J. (Editor)
2008-01-01
The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the development documents from the GCS project. Volume 2 contains three appendices: A. Guidance and Control Software Development Specification; B. Design Description for the Pluto Implementation of the Guidance and Control Software; and C. Source Code for the Pluto Implementation of the Guidance and Control Software
Fixed site neutralization model programmer's manual. Volume II
Engi, D.; Chapman, L.D.; Judnick, W.; Blum, R.; Broegler, L.; Lenz, J.; Weinthraub, A.; Ballard, D.
1979-12-01
This report relates to protection of nuclear materials at nuclear facilities. This volume presents the source listings for the Fixed Site Neutralization Model and its supporting modules, the Plex Preprocessor and the Data Preprocessor
Confining dyon gas with finite-volume effects under control
Bruckmann, Falk [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Dinter, Simon [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Ilgenfritz, Ernst-Michael [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Joint Institute for Nuclear Research, VBLHEP, Dubna (Russian Federation); Maier, Benjamin; Mueller-Preussker, Michael [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Wagner, Marc [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik
2011-11-15
As an approach to describe the long-range properties of non-Abelian gauge theories at non-zero temperature T
Confining dyon gas with finite-volume effects under control
Bruckmann, Falk; Maier, Benjamin; Mueller-Preussker, Michael; Wagner, Marc; Frankfurt Univ.
2011-11-01
As an approach to describe the long-range properties of non-Abelian gauge theories at non-zero temperature T c , we consider a non-interacting ensemble of dyons (magnetic monopoles) with non-trivial holonomy. We show analytically, that the quark-antiquark free energy from the Polyakov loop correlator grows linearly with the distance, and how the string tension scales with the dyon density. In numerical treatments, the long-range tails of the dyon fields cause severe finite-volume effects. Therefore, we demonstrate the application of Ewald's summation method to this system. Finite-volume effects are shown to be under control, which is a crucial requirement for numerical studies of interacting dyon ensembles. (orig.)
Guidance and Control Software Project Data - Volume 1: Planning Documents
Hayhurst, Kelly J. (Editor)
2008-01-01
The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the planning documents from the GCS project. Volume 1 contains five appendices: A. Plan for Software Aspects of Certification for the Guidance and Control Software Project; B. Software Development Standards for the Guidance and Control Software Project; C. Software Verification Plan for the Guidance and Control Software Project; D. Software Configuration Management Plan for the Guidance and Control Software Project; and E. Software Quality Assurance Activities.
Guidance and Control Software Project Data - Volume 3: Verification Documents
Hayhurst, Kelly J. (Editor)
2008-01-01
The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the verification documents from the GCS project. Volume 3 contains four appendices: A. Software Verification Cases and Procedures for the Guidance and Control Software Project; B. Software Verification Results for the Pluto Implementation of the Guidance and Control Software; C. Review Records for the Pluto Implementation of the Guidance and Control Software; and D. Test Results Logs for the Pluto Implementation of the Guidance and Control Software.
Automated high speed volume computed tomography for inline quality control
Hanke, R.; Kugel, A.; Troup, P.
2004-01-01
Increasing complexity of innovative products as well as growing requirements on quality and reliability call for more detailed knowledge about internal structures of manufactured components rather by 100 % inspection than just by sampling test. A first-step solution, like radioscopic inline inspection machines, equipped with automated data evaluation software, have become state of the art in the production floor during the last years. However, these machines provide just ordinary two-dimensional information and deliver no volume data e.g. to evaluate exact position or shape of detected defects. One way to solve this problem is the application of X-ray computed tomography (CT). Compared to the performance of the first generation medical scanners (scanning times of many hours), today, modern Volume CT machines for industrial applications need about 5 minutes for a full object scan depending on the object size. Of course, this is still too long to introduce this powerful method into the inline production quality control. In order to gain acceptance, the scanning time including subsequent data evaluation must be decreased significantly and adapted to the manufacturing cycle times. This presentation demonstrates the new technical set up, reconstruction results and the methods for high-speed volume data evaluation of a new fully automated high-speed CT scanner with cycle times below one minute for an object size of less than 15 cm. This will directly create new opportunities in design and construction of more complex objects. (author)
1996-01-01
The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues
NONE
1996-02-26
The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.
Modeling truck traffic volume growth congestion.
2009-05-01
Modeling of the statewide transportation system is an important element in understanding issues and programming of funds to thwart potential congestion. As Alabama grows its manufacturing economy, the number of heavy vehicles traversing its highways ...
Tracer responses and control of vessels with variable flow and volume
Niemi, A.J.
1990-01-01
Continuous flow vessels which are subject to variation of flow and volume are characterized by time-variable parameters. It is shown that their residence time distributions and weighting functions obtained by tracer testing are made invariant with regard to the integrated flow variables which are introduced. Under variable flow but constant volume, one such integrated variable is sufficient. Under variable volume, two different variables are suggested for the residence time distribution and weighting function, while the appropriate variable of the perfect mixer differs distinctly from that of vessels with a distinct velocity profile. It is shown through a number of example cases, that an agreement with their mathematical models is reached. The approach is extended to include also arbitrary, non-analytic response functions obtained by tracer measurements. Applications of the derived models and their incorporation in automatic control algorithms is discussed. (orig.) [de
Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes
Petr KOŇAŘÍK
2009-06-01
Full Text Available Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cylinder. Presented paper deal with development of extended form of analytic linear model of single piston rod hydraulic cylinder which respects different action piston areas and volumes inside of chambers of hydraulic cylinder and also two different input flows of hydraulic cylinder. In extended model are also considered possibilities of different dead volumes in hoses and intake parts of hydraulic cylinder. Dead volume has impact on damping of hydraulic cylinder. Because the system of hydraulic cylinder is generally presented as a integrative system with inertia of second order: eq , we can than obtain time constants and damping of hydraulic cylinder for each of analytic form model. The model has arisen for needs of model fractionation on two parts. Part of behaviour of chamber A and part of behaviour of chamber B of cylinder. It was created for the reason of analysis and synthesis of control parameters of regulation circuit of multivalve control concept of hydraulic drive with separately controlled chamber A and B which could be then used for.
Spatial Economics Model Predicting Transport Volume
Lu Bo
2016-10-01
Full Text Available It is extremely important to predict the logistics requirements in a scientific and rational way. However, in recent years, the improvement effect on the prediction method is not very significant and the traditional statistical prediction method has the defects of low precision and poor interpretation of the prediction model, which cannot only guarantee the generalization ability of the prediction model theoretically, but also cannot explain the models effectively. Therefore, in combination with the theories of the spatial economics, industrial economics, and neo-classical economics, taking city of Zhuanghe as the research object, the study identifies the leading industry that can produce a large number of cargoes, and further predicts the static logistics generation of the Zhuanghe and hinterlands. By integrating various factors that can affect the regional logistics requirements, this study established a logistics requirements potential model from the aspect of spatial economic principles, and expanded the way of logistics requirements prediction from the single statistical principles to an new area of special and regional economics.
Mathematical models for volume rendering and neutron transport
Max, N.
1994-09-01
This paper reviews several different models for light interaction with volume densities of absorbing, glowing, reflecting, or scattering material. They include absorption only, glow only, glow and absorption combined, single scattering of external illumination, and multiple scattering. The models are derived from differential equations, and illustrated on a data set representing a cloud. They are related to corresponding models in neutron transport. The multiple scattering model uses an efficient method to propagate the radiation which does not suffer from the ray effect
The System 80+ Standard Plant design control document. Volume 11
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume covers parts 6 and 7 and appendix 7A for section 7 (Instrumentation and Control) of the ADM Design and Analysis. The topics covered by these are: other systems required for safety; control systems not required by safety; and CMF evaluation of limiting faults. Parts 1--3 of section 8 (Electric Power) of the ADM are also included in this volume. Topics covered by these parts are: introduction; offsite power system; and onsite power system
The System 80+ Standard Plant design control document. Volume 20
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains 2 technical specifications bases as part of Appendix 16 A Tech Spec Bases. They are TS B3.8 Electrical Power Technical Systems Bases and TS B3.9 Refueling Operations Bases. All 3 parts of section 17 (QA) and all 10 parts of section 18 (Human Factors) of the ADM Design and Analysis are contained in this volume. Topics covered in section 17 are: design phase QA; operations phase QA; and design phase reliability assurance. Topics covered by section 18 are: design team organization; design goals; design process; functional task analysis; control room configuration; information presentation; control and monitoring; verification and validation; and review documents
Morphological modeling of terrains and volume data
Comic, Lidija; Magillo, Paola; Iuricich, Federico
2014-01-01
This book describes the mathematical background behind discrete approaches to morphological analysis of scalar fields, with a focus on Morse theory and on the discrete theories due to Banchoff and Forman. The algorithms and data structures presented are used for terrain modeling and analysis, molecular shape analysis, and for analysis or visualization of sensor and simulation 3D data sets. It covers a variety of application domains including geography, geology, environmental sciences, medicine and biology. The authors classify the different approaches to morphological analysis which are all ba
Alligator Rivers Analogue project. Hydrogeological modelling. Final Report - Volume 6
Townley, L.R.; Trefry, M.G.; Barr, A.D.; Braumiller, S.
1992-01-01
This volume describes hydrogeological modelling carried out as part of the Alligator Rivers Analogue Project. Hydrogeology has played a key integrating role in the Project, largely because water movement is believed to have controlled the evolution of the Koongarra uranium Orebody and therefore affects field observations of all types at all scales. Aquifer testing described uses the concept of transmissivity in its interpretation of aquifer response to pumping. The concept of an aquifer, a layer transmitting significant quantities of water in a mainly horizontal direction, seems hard to accept in an environment as heterogeneous as that at Koongarra. But modelling of aquifers both in one dimension and two dimensionally in plan has contributed significantly to our understanding of the site. A one-dimensional model with three layers (often described as a quasi two dimensional model) was applied to flow between the Fault and Koongarra Creek. Being a transient model, this model was able to show that reverse flows can indeed occur back towards the Fault, but only if there is distributed recharge over the orebody as well as a mechanism for the Fault, or a region near the Fault, to remove water from the simulated cross-section. The model also showed clearly that the response of the three-layered system, consisting of a highly weathered zone, a fractured transmissive zone and a less conductive lower schist zone, is governed mainly by the transmissivity and storage coefficient of the middle layer. The storage coefficient of the higher layer has little effect. A two-dimensional model in plan used a description of anisotropy to show that reverse flows can also occur even without a conducting Fault. Modelling of a three-dimensional region using discrete fractures showed that it is certainly possible to simulate systems like that observed at Koongarra, but that large amounts of data are probably needed to obtain realistic descriptions of the fracture networks. Inverse modelling
Alligator Rivers Analogue project. Hydrogeological modelling. Final Report - Volume 6
Townley, L R; Trefry, M G; Barr, A D [CSIRO Div of Water Resources, PO Wembley, WA (Australia); Braumiller, S [Univ of Arizona, Tucson, AZ (United States). Dept of Hydrology and Water Resources; Kawanishi, M [Central Research Institute of Electric Power Industry, Abiko-Shi, Chiba-Ken (Japan); and others
1993-12-31
This volume describes hydrogeological modelling carried out as part of the Alligator Rivers Analogue Project. Hydrogeology has played a key integrating role in the Project, largely because water movement is believed to have controlled the evolution of the Koongarra uranium Orebody and therefore affects field observations of all types at all scales. Aquifer testing described uses the concept of transmissivity in its interpretation of aquifer response to pumping. The concept of an aquifer, a layer transmitting significant quantities of water in a mainly horizontal direction, seems hard to accept in an environment as heterogeneous as that at Koongarra. But modelling of aquifers both in one dimension and two dimensionally in plan has contributed significantly to our understanding of the site. A one-dimensional model with three layers (often described as a quasi two dimensional model) was applied to flow between the Fault and Koongarra Creek. Being a transient model, this model was able to show that reverse flows can indeed occur back towards the Fault, but only if there is distributed recharge over the orebody as well as a mechanism for the Fault, or a region near the Fault, to remove water from the simulated cross-section. The model also showed clearly that the response of the three-layered system, consisting of a highly weathered zone, a fractured transmissive zone and a less conductive lower schist zone, is governed mainly by the transmissivity and storage coefficient of the middle layer. The storage coefficient of the higher layer has little effect. A two-dimensional model in plan used a description of anisotropy to show that reverse flows can also occur even without a conducting Fault. Modelling of a three-dimensional region using discrete fractures showed that it is certainly possible to simulate systems like that observed at Koongarra, but that large amounts of data are probably needed to obtain realistic descriptions of the fracture networks. Inverse modelling
An operator calculus for surface and volume modeling
Gordon, W. J.
1984-01-01
The mathematical techniques which form the foundation for most of the surface and volume modeling techniques used in practice are briefly described. An outline of what may be termed an operator calculus for the approximation and interpolation of functions of more than one independent variable is presented. By considering the linear operators associated with bivariate and multivariate interpolation/approximation schemes, it is shown how they can be compounded by operator multiplication and Boolean addition to obtain a distributive lattice of approximation operators. It is then demonstrated via specific examples how this operator calculus leads to practical techniques for sculptured surface and volume modeling.
Control and dynamic systems: advances in theory and applications. Volume 14, 1978
Leondes, C.T.
1978-01-01
The theme for this volume, containing five contributions, is models for complex and/or large-scale engineering systems. The first contribution deals with techniques of modeling and model error compensation in linear regulator problems. The next contribution, on pressurized water reactors, deals with many important systems modeling and control issues in nuclear reactors. The next two contributions serve as a companion set on models for the aircraft jet engine. The first presents the modeling formulation problems for such systems from the point of view of physics and engineering technology; the second emphasizes the system state equation and effective control principles. The last contribution deals with complex many-element power systems, but the techniques presented are generally applicable to any complex engineering system in which there are many interacting elements
Active control: Wind turbine model
Bindner, Henrik
1999-07-01
This report is a part of the reporting of the work done in the project `Active Control of Wind Turbines`. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to design controllers. This report describes the model developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This has been done with extensive use of measurements as the basis for selection of model complexity and model validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending, a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models. The models are all formulated as linear differential equations. The models are validated through comparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind turbine. The model and the measurements corresponds well in the relevant frequency range. The developed model is therefore applicable for controller design. (au) EFP-91. 18 ills., 22 refs.
The System 80+ Standard Plant design control document. Volume 23
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains part 16 References and Appendix 19 A Design Alternatives for section 19 (Probabilistic Risk Assessment) of the ADM Design and Analysis. Also covered is section 20 Unresolved Safety Issues of the ADM Design and Analysis. Finally sections 1--6 of the ADM Emergency Operations Guidelines are contained in this volume. Information covered in these sections include: standard post-trip actions; diagnostic actions; reactor trip recovery guideline; LOCA recovery; SG tube rupture recovery
The System 80+ Standard Plant design control document. Volume 21
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains parts 1--10 of section 19 (Probabilistic Risk Assessment) of the ADM Design and Analysis. Topics covered are: methodology; initiating event evaluation; accident sequence determination; data analysis; systems analysis; external events analysis; shutdown risk assessment; accident sequence quantification; and sensitivity analysis. Also included in this volume are Appendix 19.8A Shutdown Risk Assessment and Appendix A to Appendix 19.8A Request for Information
The System 80+ Standard Plant design control document. Volume 2
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume covers the following information of the CDM: (2.8) Steam and power conversion; (2.9) Radioactive waste management; (2.10) Tech Support Center; (2.11) Initial test program; (2.12) Human factors; and sections 3, 4, and 5. Also covered in this volume are parts 1--6 of section 1 (General Plant Description) of the ADM Design and Analysis
The System 80+ Standard Plant design control document. Volume 15
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains all five parts of section 12 (Radiation Protection) of the ADM Design and Analysis. Topics covered are: ALARA exposures; radiation sources; radiation protection; dose assessment; and health physics program. All six parts and appendices A and B for section 13 (Conduct of Operations) of the ADM Design and Analysis are also contained in this volume. Topics covered are: organizational structure; training program; emergency planning; review and audit; plant procedures; industrial security; sabotage protection (App 13A); and vital equipment list (App 13B)
Active control: Wind turbine model
Bindner, H.
1999-01-01
This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending,a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models...
High-volume manufacturing device overlay process control
Lee, Honggoo; Han, Sangjun; Woo, Jaeson; Lee, DongYoung; Song, ChangRock; Heo, Hoyoung; Brinster, Irina; Choi, DongSub; Robinson, John C.
2017-03-01
Overlay control based on DI metrology of optical targets has been the primary basis for run-to-run process control for many years. In previous work we described a scenario where optical overlay metrology is performed on metrology targets on a high frequency basis including every lot (or most lots) at DI. SEM based FI metrology is performed ondevice in-die as-etched on an infrequent basis. Hybrid control schemes of this type have been in use for many process nodes. What is new is the relative size of the NZO as compared to the overlay spec, and the need to find more comprehensive solutions to characterize and control the size and variability of NZO at the 1x nm node: sampling, modeling, temporal frequency and control aspects, as well as trade-offs between SEM throughput and accuracy.
Temporal validation for landsat-based volume estimation model
Renaldo J. Arroyo; Emily B. Schultz; Thomas G. Matney; David L. Evans; Zhaofei Fan
2015-01-01
Satellite imagery can potentially reduce the costs and time associated with ground-based forest inventories; however, for satellite imagery to provide reliable forest inventory data, it must produce consistent results from one time period to the next. The objective of this study was to temporally validate a Landsat-based volume estimation model in a four county study...
The System 80+ Standard Plant design control document. Volume 18
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains the following technical specifications of section 16 (Technical Specifications) of the ADM Design and Analysis: TS 3.3 Instrumentation; TS 3.4 Reactor Coolant System; TS 3.5 Emergency Core Cooling System; TS 3.6 Containment Systems; TS 3.7 Plant Systems; TS 3.8 Electrical Power Systems; TS 3.9 Refueling Operations; TS 4.0 Design Features; TS 5.0 Administrative Controls. Appendix 16 A Tech Spec Bases is also included. It contains the following: TS B2.0 Safety Limits Bases; TS B3.0 LCO Applicability Bases; TS B3.1 Reactivity Control Bases; TS B3.2 Power Distribution Bases
Controlling cell volume for efficient PHB production by Halomonas.
Jiang, Xiao-Ran; Yao, Zhi-Hao; Chen, Guo-Qiang
2017-11-01
Bacterial morphology is decided by cytoskeleton protein MreB and cell division protein FtsZ encoded by essential genes mreB and ftsZ, respectively. Inactivating mreB and ftsZ lead to increasing cell sizes and cell lengths, respectively, yet seriously reduce cell growth ability. Here we develop a temperature-responsible plasmid expression system for compensated expression of relevant gene(s) in mreB or ftsZ disrupted recombinants H. campaniensis LS21, allowing mreB or ftsZ disrupted recombinants to grow normally at 30°C in a bioreactor for 12h so that a certain cell density can be reached, followed by 36h cell size expansions or cell shape elongations at elevated 37°C at which the mreB and ftsZ encoded plasmid pTKmf failed to replicate in the recombinants and thus lost themselves. Finally, 80% PHB yield increase was achieved via controllable morphology manipulated H. campaniensis LS21. It is concluded that controllable expanding cell volumes (widths or lengths) provides more spaces for accumulating more inclusion body polyhydroxybutyrate (PHB) and the resulting cell gravity precipitation benefits the final separation of cells and product during downstream. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.
Controlling chaos in Internet congestion control model
Chen Liang; Wang Xiaofan; Han Zhengzhi
2004-01-01
The TCP end-to-end congestion control plus RED router queue management can be modeled as a discrete-time dynamical system, which may create complex bifurcating and chaotic behavior. Based on the basic features of the TCP-RED model, we propose a time-dependent delayed feedback control algorithm to control chaos in the system by perturbing the accessible RED parameter p max . This method is able to stabilized a router queue occupancy at a level without knowing the exact knowledge of the network. Further, we study the situation of the presence of the UDP traffic
Controlling chaos in Internet congestion control model
Chen Liang E-mail: chenmoon110@yahoo.com.cn; Wang Xiaofan; Han Zhengzhi
2004-07-01
The TCP end-to-end congestion control plus RED router queue management can be modeled as a discrete-time dynamical system, which may create complex bifurcating and chaotic behavior. Based on the basic features of the TCP-RED model, we propose a time-dependent delayed feedback control algorithm to control chaos in the system by perturbing the accessible RED parameter p{sub max}. This method is able to stabilized a router queue occupancy at a level without knowing the exact knowledge of the network. Further, we study the situation of the presence of the UDP traffic.
A volume flexible inventory model with trapezoidal demand under inflation
kapil mehrotra
2014-02-01
Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Abstract This article experiment. Further, the effects of different parameters are analysed by performing sensitivity analyses on the optimal policy. explores an economic production quantity model (EPQ model for deteriorating items with time-dependent demand following trapezoidal pattern taking the volume flexibility into account. We have also considered the inflation and time value of money. The solution of the model aims at determining the optimal production run-time in order to maximize the profit. The model is also illustrated by means of numerical
Model for the radionuclide measurement of ascitic fluid volumes
Kaplan, W.D.; Davis, M.A.; Uren, R.F.; Wisotsky, T.; LaTegola, M.
1978-01-01
Technetium-99m phytate colloids formed in vitro and in vivo were examined as radioindicators for estimation of the volume of third-space fluid in an ovarian ascites model using C3HeB/FeJ mice. In double-label experiments, the accuracy of the colloids for dilution analysis was found to be equal or superior to that of I-125 HSA. Sampling times 3 to 5 min after intraperitoneal administration were found to produce the best volume estimates. Four needle-stopcock assemblies inserted sequentially into the quadrants of the peritoneal cavity were used for administration and sampling of the radioindicators. The stopcocks could be closed to prevent leakage of ascitic fluid during the procedure. In contrast to radiolabeled albumin, Tc-99m phytate colloids have clinical use for simultaneous imaging of radiotracer migration to assess potential occlusion of diaphragmatic lymphatics by neoplastic cells, and for dilution analysis to estimate volume of ascitic fluid
Development of a hip joint model for finite volume simulations.
Cardiff, P; Karač, A; FitzPatrick, D; Ivanković, A
2014-01-01
This paper establishes a procedure for numerical analysis of a hip joint using the finite volume method. Patient-specific hip joint geometry is segmented directly from computed tomography and magnetic resonance imaging datasets and the resulting bone surfaces are processed into a form suitable for volume meshing. A high resolution continuum tetrahedral mesh has been generated, where a sandwich model approach is adopted; the bones are represented as a stiffer cortical shells surrounding more flexible cancellous cores. Cartilage is included as a uniform thickness extruded layer and the effect of layer thickness is investigated. To realistically position the bones, gait analysis has been performed giving the 3D positions of the bones for the full gait cycle. Three phases of the gait cycle are examined using a finite volume based custom structural contact solver implemented in open-source software OpenFOAM.
The System 80+ Standard Plant design control document. Volume 1
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume covers the DCD introduction and contains sections 1 and parts 1--7 of section 2 of the CDM. Parts 1--7 included the following: (2.1) Design of SSC; (2.2) Reactor; (2.3) RCS and connected systems; (2.4) Engineered Safety Features; (2.5) Instrumentation and Control; (2.6) Electric Power; and (2.7) Auxiliary Systems
The System 80+ Standard Plant design control document. Volume 10
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains Appendices 6A, 6B, and 6C for section 6 (Engineered Safety Features) of the ADM Design and Analysis. Also, parts 1--5 of section 7 (Instrumentation and Control) of the ADM Design and Analysis are covered. The following information is covered in these parts: introduction; reactor protection system; ESF actuation system; system required for safe shutdown; and safety-related display instrumentation
BRUNO DO VALLE PINHEIRO
2002-01-01
Full Text Available Introdução: Persiste a questão sobre se há vantagens mecânicas ou de trocas gasosas no uso da ventilação pressão-controlada (VPC sobre a ciclada a volume (VCV. Objetivos: Comparar, de forma randômica, a VPC com a VCV com fluxo desacelerado nos modos assistido e controlado em modelo experimental de lesão pulmonar aguda. Métodos: Sete cães com lesão pulmonar aguda grave (PaO2/FIO2 Background: It is questionable whether pressure-controlled ventilation (PCV has advantages over volume-cycled ventilation (VCV. Objectives: To compare PCV to VCV with decelerating flow profile during assisted and controlled modes in an acute lung injury experimental model. Methods: Severe acute lung injury (PaO2/FIO2 < 100 mmHg was induced by oleic acid IV infusion (0.05 mg/kg in seven dogs. The animals were submitted to PCV and VCV in a randomized sequence. After 40 minutes in the assisted mode, ventilation was changed to the controlled mode after neuromuscular blockade. The tidal volume and the inspiratory time were kept constant throughout the experiment. Results: There were no differences in gas exchange (PaO2 and PaCO2, cardiac output or oxygen delivery (DO2 between VCV and PCV. The same was observed regarding maximum airway and plateau pressures, and also to the static compliance. Oxygen consumption (VO2 after neuromuscular blockade was 124 ± 48 in VCV versus 143 ± 50 ml/min in PCV, p = 0.42. In the assisted mode, there was a statistical trend of a higher VO2 in PCV (219 ± 72 versus 154 ± 67 ml/min in VCV, p = 0.06, that was associated with a statistical trend of a higher oxygen cost of breathing (OCB during assisted PCV, although without statistical significance (31 ± 77 in VCV versus 75 ± 96 ml/min in PCV, p = 0.23, and also in a lower PvO2 (34 ± 7 in PCV versus 42 ± 6 ml/min in VCV, p = 0.02. These occurred despite a higher maximum inspiratory flow in the assisted mode in PCV (58 ± 9 versus 48 ± 4 L/min in VCV, p = 0.01. In both VCV and
Ball, J. W.
1976-01-01
Wind tunnel tests are reported on a 0.015-scale SSV orbiter model with remote independently operated left and right elevon surfaces. Special attention was directed to definition of nonlinear aerodynamic characteristics by taking data at small increments. Six component aerodynamic force and moment and elevon position data were recorded for the space shuttle orbiter with various elevon, aileron rudder and speed brake deflection combinations over an angle of attack range from -4 deg to 32 deg at angles of sideslip of 0 deg and 3 deg. Additional tests were made over an angle of sideslip range from -6 deg to 8 deg at selected angles of attack. Test Mach numbers were 2.86, 2.90, 3.90 and 4.60 with Reynolds numbers held at a constant 2.0 x 1 million per foot.
Modelling and controlling hydropower plants
Munoz-Hernandez, German Ardul; Jones, Dewi Ieuan
2013-01-01
Hydroelectric power stations are a major source of electricity around the world; understanding their dynamics is crucial to achieving good performance. Modelling and Controlling Hydropower Plants discusses practical and well-documented cases of modelling and controlling hydropower station modelling and control, focussing on a pumped storage scheme based in Dinorwig, North Wales. Single-input-single-output and multiple-input-multiple-output models, which cover the linear and nonlinear characteristics of pump-storage hydroelectric power stations, are reviewed. The most important dynamic features are discussed, and the verification of these models by hardware in the loop simulation is described. To show how the performance of a pump-storage hydroelectric power station can be improved, classical and modern controllers are applied to simulated models of the Dinorwig power plant. These include PID, fuzzy approximation, feed-forward and model-based predictive control with linear and hybrid prediction models. Mod...
Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes
Petr KOŇAŘÍK
2009-01-01
Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod) and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cyl...
Park, Kyungnam; Lee, Jangyoung; Kim, Soo-Young; Kim, Jinwoo; Kim, Insoo; Choi, Seung Pill; Jeong, Sikyung; Hong, Sungyoup
2013-06-01
This study assessed the method of fluid infusion control using an IntraVenous Infusion Controller (IVIC). Four methods of infusion control (dial flow controller, IV set without correction, IV set with correction and IVIC correction) were used to measure the volume of each technique at two infusion rates. The infused fluid volume with a dial flow controller was significantly larger than other methods. The infused fluid volume was significantly smaller with an IV set without correction over time. Regarding the concordance correlation coefficient (CCC) of infused fluid volume in relation to a target volume, IVIC correction was shown to have the highest level of agreement. The flow rate measured in check mode showed a good agreement with the volume of collected fluid after passing through the IV system. Thus, an IVIC could assist in providing an accurate infusion control. © 2013 Wiley Publishing Asia Pty Ltd.
RELAP5/MOD3 code manual: Code structure, system models, and solution methods. Volume 1
1995-08-01
The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling, approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I provides modeling theory and associated numerical schemes
Engine Modelling for Control Applications
Hendricks, Elbert
1997-01-01
In earlier work published by the author and co-authors, a dynamic engine model called a Mean Value Engine Model (MVEM) was developed. This model is physically based and is intended mainly for control applications. In its newer form, it is easy to fit to many different engines and requires little...... engine data for this purpose. It is especially well suited to embedded model applications in engine controllers, such as nonlinear observer based air/fuel ratio and advanced idle speed control. After a brief review of this model, it will be compared with other similar models which can be found...
Sharma, A.S.; Limebeer, D.J.N.; Jaimoukha, I.M.; Lister, J.B.
2001-11-01
A new approach to the modelling and control of tokamak fusion reactors is presented. A nonlinear model is derived using the classical arguments of Hamiltonian mechanics and a low-order linear model is derived from it. The modelling process used here addresses flux and energy conservation issues explicitly and self-consistently. The model is of particular value, because it shows the relationship between the initial modelling assumptions and the resulting predictions. The mechanisms behind the creation of uncontrollable modes in tokamak models are discussed. A normalised coprime factorisation controller is developed for the TCV tokamak using the verified linear model. Recent theory is applied to reduce the controller order significantly whilst guaranteeing a priori bounds on the robust stability and performance. The controller is shown to track successfully reference signals that dictate the plasma's shape, position and current. The tests used to verify this were carried out on linear and nonlinear models. (author)
Sharma, A.S.; Limebeer, D.J.N.; Jaimoukha, I.M.; Lister, J.B
2001-11-01
A new approach to the modelling and control of tokamak fusion reactors is presented. A nonlinear model is derived using the classical arguments of Hamiltonian mechanics and a low-order linear model is derived from it. The modelling process used here addresses flux and energy conservation issues explicitly and self-consistently. The model is of particular value, because it shows the relationship between the initial modelling assumptions and the resulting predictions. The mechanisms behind the creation of uncontrollable modes in tokamak models are discussed. A normalised coprime factorisation controller is developed for the TCV tokamak using the verified linear model. Recent theory is applied to reduce the controller order significantly whilst guaranteeing a priori bounds on the robust stability and performance. The controller is shown to track successfully reference signals that dictate the plasma's shape, position and current. The tests used to verify this were carried out on linear and nonlinear models. (author)
The System 80+ Standard Plant design control document. Volume 19
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains five technical specification bases that are part of Appendix 16 A of the ADM Design and Analysis. They are: TS B3.3 Instrumentation Bases; TS B3.4 RCS Bases; TS B3.5 ECCS Bases; TS B3.6 Containment Systems Bases; and TS B3.7 Plant Systems Bases
The System 80+ Standard Plant design control document. Volume 24
1997-01-01
This Design Control Document (DCD) is a repository of information comprising the System 80+trademark Standard Plant Design. The DCD also provides that design-related information to be incorporated by reference in the design certification rule for the System 80+ Standard Plant Design. Applicants for a combined license pursuant to 10 CFR 52 must ensure that the final Design Certification Rule and the associated Statements of Consideration are used when making all licensing decisions relevant to the System 80+ Standard Plant Design. The Design Control Document contains the DCD introduction, The Certified Design Material (CDM) [i.e., ''Tier 1''] and the Approved Design Material (ADM) [i.e., ''Tier 2''] for the System 80+ Standard Plant Design. The CDM includes the following sections: (1) Introductory material; (2) Certified Design Material for System 80+ systems and structures; (3) Certified Design Material for non-system-based aspects of the System 80+ Certified design; (4) Interface requirements; and (5) Site parameters. The ADM, to the extent applicable for the System 80+ Standard Plant Design, includes: (1) the information required for the final safety analysis report under 20 CFR 50.34; (2) other relevant information required by 10 CFR 52.47; and (3) emergency operations guidelines. This volume contains sections 7--11 of the ADM Emergency Operations Guidelines. Topics covered are: excess steam demand recovery; loss of all feedwater; loss of offsite power; station blackout recovery; and functional recovery guideline. Appendix A Severe Accident Management Guidelines and Appendix B Lower Mode Operational Guidelines are also included
NONE
1994-02-24
The Natural Gas Transmission and Distribution Model (NGTDM) is a component of the National Energy Modeling System (NEMS) used to represent the domestic natural gas transmission and distribution system. NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the Energy Information Administration (EIA) and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. This report documents the archived version of NGTDM that was used to produce the natural gas forecasts used in support of the Annual Energy Outlook 1994, DOE/EIA-0383(94). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. It is intended to fulfill the legal obligation of the EIA to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). This report represents Volume 1 of a two-volume set. (Volume 2 will report on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.) Subsequent chapters of this report provide: (1) an overview of the NGTDM (Chapter 2); (2) a description of the interface between the National Energy Modeling System (NEMS) and the NGTDM (Chapter 3); (3) an overview of the solution methodology of the NGTDM (Chapter 4); (4) the solution methodology for the Annual Flow Module (Chapter 5); (5) the solution methodology for the Distributor Tariff Module (Chapter 6); (6) the solution methodology for the Capacity Expansion Module (Chapter 7); (7) the solution methodology for the Pipeline Tariff Module (Chapter 8); and (8) a description of model assumptions, inputs, and outputs (Chapter 9).
Thosar, Archana; Patra, Amit; Bhattacharyya, Souvik
2008-07-01
Design of a nonlinear control system for a Variable Air Volume Air Conditioning (VAVAC) plant through feedback linearization is presented in this article. VAVAC systems attempt to reduce building energy consumption while maintaining the primary role of air conditioning. The temperature of the space is maintained at a constant level by establishing a balance between the cooling load generated in the space and the air supply delivered to meet the load. The dynamic model of a VAVAC plant is derived and formulated as a MIMO bilinear system. Feedback linearization is applied for decoupling and linearization of the nonlinear model. Simulation results for a laboratory scale plant are presented to demonstrate the potential of keeping comfort and maintaining energy optimal performance by this methodology. Results obtained with a conventional PI controller and a feedback linearizing controller are compared and the superiority of the proposed approach is clearly established.
Modeling and Control for Microgrids
Steenis, Joel
Traditional approaches to modeling microgrids include the behavior of each inverter operating in a particular network configuration and at a particular operating point. Such models quickly become computationally intensive for large systems. Similarly, traditional approaches to control do not use advanced methodologies and suffer from poor performance and limited operating range. In this document a linear model is derived for an inverter connected to the Thevenin equivalent of a microgrid. This model is then compared to a nonlinear simulation model and analyzed using the open and closed loop systems in both the time and frequency domains. The modeling error is quantified with emphasis on its use for controller design purposes. Control design examples are given using a Glover McFarlane controller, gain scheduled Glover McFarlane controller, and bumpless transfer controller which are compared to the standard droop control approach. These examples serve as a guide to illustrate the use of multi-variable modeling techniques in the context of robust controller design and show that gain scheduled MIMO control techniques can extend the operating range of a microgrid. A hardware implementation is used to compare constant gain droop controllers with Glover McFarlane controllers and shows a clear advantage of the Glover McFarlane approach.
Volume-Targeted Ventilation in the Neonate: Benchmarking Ventilators on an Active Lung Model.
Krieger, Tobias J; Wald, Martin
2017-03-01
Mechanically ventilated neonates have been observed to receive substantially different ventilation after switching ventilator models, despite identical ventilator settings. This study aims at establishing the range of output variability among 10 neonatal ventilators under various breathing conditions. Relative benchmarking test of 10 neonatal ventilators on an active neonatal lung model. Neonatal ICU. Ten current neonatal ventilators. Ventilators were set identically to flow-triggered, synchronized, volume-targeted, pressure-controlled, continuous mandatory ventilation and connected to a neonatal lung model. The latter was configured to simulate three patients (500, 1,500, and 3,500 g) in three breathing modes each (passive breathing, constant active breathing, and variable active breathing). Averaged across all weight conditions, the included ventilators delivered between 86% and 110% of the target tidal volume in the passive mode, between 88% and 126% during constant active breathing, and between 86% and 120% under variable active breathing. The largest relative deviation occurred during the 500 g constant active condition, where the highest output machine produced 147% of the tidal volume of the lowest output machine. All machines deviate significantly in volume output and ventilation regulation. These differences depend on ventilation type, respiratory force, and patient behavior, preventing the creation of a simple conversion table between ventilator models. Universal neonatal tidal volume targets for mechanical ventilation cannot be transferred from one ventilator to another without considering necessary adjustments.
ECONOMIC MODELING STOCKS CONTROL SYSTEM: SIMULATION MODEL
Климак, М.С.; Войтко, С.В.
2016-01-01
Considered theoretical and applied aspects of the development of simulation models to predictthe optimal development and production systems that create tangible products andservices. It isproved that theprocessof inventory control needs of economicandmathematical modeling in viewof thecomplexity of theoretical studies. A simulation model of stocks control that allows make managementdecisions with production logistics
Jamaluddin1*
2011-06-01
Full Text Available Expansion and puffing are specific characteristics of fried products critical for consumer preferences. To obtain expanded and puffed dried products that fit well with consumer acceptance criteria, it is necessary to pay attention to the process conditions which change the raw material characteristics during frying. The important changes include volume and density ratio of the products during frying. Hypothetically, these changes are due to water vaporization and the decrease dry matter in the products. The objective of this research is to develop a mathematical model of volume and density ratio changes for jack fruit during vacuum frying as a function of water and starch content reductions. Samples were vacuum fried at 70–100OC and pressure of 80-90 kPa for 15–60 min. The parameters observed were volume and density as well as water and starch contents of samples before and after vacuum frying. The results showed that the developed model can be used to predict changes in volume and density ratio of jack fruit during vacuum frying.
MODEL PREDICTIVE CONTROL FUNDAMENTALS
2012-07-02
Jul 2, 2012 ... signal based on a process model, coping with constraints on inputs and ... paper, we will present an introduction to the theory and application of MPC with Matlab codes ... section 5 presents the simulation results and section 6.
ATHENA code manual. Volume 1. Code structure, system models, and solution methods
Carlson, K.E.; Roth, P.A.; Ransom, V.H.
1986-09-01
The ATHENA (Advanced Thermal Hydraulic Energy Network Analyzer) code has been developed to perform transient simulation of the thermal hydraulic systems which may be found in fusion reactors, space reactors, and other advanced systems. A generic modeling approach is utilized which permits as much of a particular system to be modeled as necessary. Control system and secondary system components are included to permit modeling of a complete facility. Several working fluids are available to be used in one or more interacting loops. Different loops may have different fluids with thermal connections between loops. The modeling theory and associated numerical schemes are documented in Volume I in order to acquaint the user with the modeling base and thus aid effective use of the code. The second volume contains detailed instructions for input data preparation
Frequency control modelling - basics
Hansen, Anca Daniela; Sørensen, Poul Ejnar; Zeni, Lorenzo
2016-01-01
The purpose of this report is to provide an introduction on how the system balance in an island system can be maintained by controlling the frequency. The power balance differential equation, which is fundamental in understanding the effect on the system frequency of the unbalance between...
High brightness diode lasers controlled by volume Bragg gratings
Glebov, Leonid
2017-02-01
Volume Bragg gratings (VBGs) recorded in photo-thermo-refractive (PTR) glass are holographic optical elements that are effective spectral and angular filters withstanding high power laser radiation. Reflecting VBGs are narrow-band spectral filters while transmitting VBGs are narrow-band angular filters. The use of these optical elements in external resonators of semiconductor lasers enables extremely resonant feedback that provides dramatic spectral and angular narrowing of laser diodes radiation without significant power and efficiency penalty. Spectral narrowing of laser diodes by reflecting VBGs demonstrated in wide spectral region from near UV to 3 μm. Commercially available VBGs have spectral width ranged from few nanometers to few tens of picometers. Efficient spectral locking was demonstrated for edge emitters (single diodes, bars, modules, and stacks), vertical cavity surface emitting lasers (VCSELs), grating coupled surface emitting lasers (GCSELs), and interband cascade lasers (ICLs). The use of multiplexed VBGs provides multiwavelength emission from a single emitter. Spectrally locked semiconductor lasers demonstrated CW power from milliwatts to a kilowatt. Angular narrowing by transmitting VBGs enables single transverse mode emission from wide aperture diode lasers having resonators with great Fresnel numbers. This feature provides close to diffraction limit divergence along a slow axis of wide stripe edge emitters. Radiation exchange between lasers by means of spatially profiled or multiplexed VBGs enables coherent combining of diode lasers. Sequence of VBGs or multiplexed VBGs enable spectral combining of spectrally narrowed diode lasers or laser modules. Thus the use of VBGs for diode lasers beam control provides dramatic increase of brightness.
Development of modelling and forecasting in geology. (Volume 2)
Seguin, J.J.; Fourniguet, J.; Peaudecerf, P.
1990-01-01
To access the long-term safety of radioactive waste disposal systems, validation of predictive models is essential and large efforts should be given to barriers, particularly geologic barriers. This work appears in the form of four volumes, the subject of the second part is described below. HERODE (calculation of relief altitude under erosion process from 0 to 100000 years) is a weathering and erosion computerized simulation. The model describes materials and rocks transport and also substratum weathering process. FORTRAN 77 is the software language. 31 figs., 6 tabs., 40 refs
Scanner baseliner monitoring and control in high volume manufacturing
Samudrala, Pavan; Chung, Woong Jae; Aung, Nyan; Subramany, Lokesh; Gao, Haiyong; Gomez, Juan-Manuel
2016-03-01
We analyze performance of different customized models on baseliner overlay data and demonstrate the reduction in overlay residuals by ~10%. Smart Sampling sets were assessed and compared with the full wafer measurements. We found that performance of the grid can still be maintained by going to one-third of total sampling points, while reducing metrology time by 60%. We also demonstrate the feasibility of achieving time to time matching using scanner fleet manager and thus identify the tool drifts even when the tool monitoring controls are within spec limits. We also explore the scanner feedback constant variation with illumination sources.
Adrenal gland volume measurement in septic shock and control patients: a pilot study
Nougaret, Stephanie; Aufort, S.; Gallix, B. [Hopital Saint Eloi, Department of Abdominal Imaging, CHU Montpellier, Montpellier, Cedex 5 (France); Jung, B.; Chanques, G.; Jaber, S. [Hopital Saint Eloi, Intensive Care Unit, Department of Critical Care and Anesthesiology: DAR B, CHU Montpellier, Montpellier, Cedex 5 (France)
2010-10-15
To compare adrenal gland volume in septic shock patients and control patients by using semi-automated volumetry. Adrenal gland volume and its inter-observer variability were measured with tomodensitometry using semi-automated software in 104 septic shock patients and in 40 control patients. The volumes of control and septic shock patients were compared and the relationship between volume and outcome in intensive care was studied. The mean total volume of both adrenal glands was 7.2 {+-} 2.0 cm{sup 3} in control subjects and 13.3 {+-} 4.7 cm{sup 3} for total adrenal gland volume in septic shock patients (p < 0.0001). Measurement reproducibility was excellent with a concordance correlation coefficient value of 0.87. The increasing adrenal gland volume was associated with a higher rate of survival in intensive care. The present study reports that with semi-automated software, adrenal gland volume can be measured easily and reproducibly. Adrenal gland volume was found to be nearly double in sepsis compared with control patients. The absence of increased volume during sepsis would appear to be associated with a higher rate of mortality and may represent a prognosis factor which may help the clinician to guide their strategy. (orig.)
Adrenal gland volume measurement in septic shock and control patients: a pilot study
Nougaret, Stephanie; Aufort, S.; Gallix, B.; Jung, B.; Chanques, G.; Jaber, S.
2010-01-01
To compare adrenal gland volume in septic shock patients and control patients by using semi-automated volumetry. Adrenal gland volume and its inter-observer variability were measured with tomodensitometry using semi-automated software in 104 septic shock patients and in 40 control patients. The volumes of control and septic shock patients were compared and the relationship between volume and outcome in intensive care was studied. The mean total volume of both adrenal glands was 7.2 ± 2.0 cm 3 in control subjects and 13.3 ± 4.7 cm 3 for total adrenal gland volume in septic shock patients (p < 0.0001). Measurement reproducibility was excellent with a concordance correlation coefficient value of 0.87. The increasing adrenal gland volume was associated with a higher rate of survival in intensive care. The present study reports that with semi-automated software, adrenal gland volume can be measured easily and reproducibly. Adrenal gland volume was found to be nearly double in sepsis compared with control patients. The absence of increased volume during sepsis would appear to be associated with a higher rate of mortality and may represent a prognosis factor which may help the clinician to guide their strategy. (orig.)
Shi, Yan; Zhang, Bolun; Cai, Maolin; Zhang, Xiaohua Douglas
2017-09-01
Mechanical ventilation is a key therapy for patients who cannot breathe adequately by themselves, and dynamics of mechanical ventilation system is of great significance for life support of patients. Recently, models of mechanical ventilated respiratory system with 1 lung are used to simulate the respiratory system of patients. However, humans have 2 lungs. When the respiratory characteristics of 2 lungs are different, a single-lung model cannot reflect real respiratory system. In this paper, to illustrate dynamic characteristics of mechanical ventilated respiratory system with 2 different lungs, we propose a mathematical model of mechanical ventilated respiratory system with 2 different lungs and conduct experiments to verify the model. Furthermore, we study the dynamics of mechanical ventilated respiratory system with 2 different lungs. This research study can be used for improving the efficiency and safety of volume-controlled mechanical ventilation system. Copyright © 2016 John Wiley & Sons, Ltd.
C. Makendran
2015-01-01
Full Text Available Prediction models for low volume village roads in India are developed to evaluate the progression of different types of distress such as roughness, cracking, and potholes. Even though the Government of India is investing huge quantum of money on road construction every year, poor control over the quality of road construction and its subsequent maintenance is leading to the faster road deterioration. In this regard, it is essential that scientific maintenance procedures are to be evolved on the basis of performance of low volume flexible pavements. Considering the above, an attempt has been made in this research endeavor to develop prediction models to understand the progression of roughness, cracking, and potholes in flexible pavements exposed to least or nil routine maintenance. Distress data were collected from the low volume rural roads covering about 173 stretches spread across Tamil Nadu state in India. Based on the above collected data, distress prediction models have been developed using multiple linear regression analysis. Further, the models have been validated using independent field data. It can be concluded that the models developed in this study can serve as useful tools for the practicing engineers maintaining flexible pavements on low volume roads.
Cell volume and membrane stretch independently control K+ channel activity
Bomholtz, Sofia Hammami; Willumsen, Niels J; Olsen, Hervør L
2009-01-01
A number of potassium channels including members of the KCNQ family and the Ca(2+) activated IK and SK, but not BK, are strongly and reversibly regulated by small changes in cell volume. It has been argued that this general regulation is mediated through sensitivity to changes in membrane stretch...... was not affected by membrane stretch. The results indicate that (1) activation of BK channels by local membrane stretch is not mimicked by membrane stress induced by cell swelling, and (2) activation of KCNQ1 channels by cell volume increase is not mediated by local tension in the cell membrane. We conclude....... To test this hypothesis we have studied the regulation of KCNQ1 and BK channels after expression in Xenopus oocytes. Results from cell-attached patch clamp studies (approximately 50 microm(2) macropatches) in oocytes expressing BK channels demonstrate that the macroscopic volume-insensitive BK current...
Diabetes: Models, Signals and control
Cobelli, C.
2010-07-01
Diabetes and its complications impose significant economic consequences on individuals, families, health systems, and countries. The control of diabetes is an interdisciplinary endeavor, which includes significant components of modeling, signal processing and control. Models: first, I will discuss the minimal (coarse) models which describe the key components of the system functionality and are capable of measuring crucial processes of glucose metabolism and insulin control in health and diabetes; then, the maximal (fine-grain) models which include comprehensively all available knowledge about system functionality and are capable to simulate the glucose-insulin system in diabetes, thus making it possible to create simulation scenarios whereby cost effective experiments can be conducted in silico to assess the efficacy of various treatment strategies - in particular I will focus on the first in silico simulation model accepted by FDA as a substitute to animal trials in the quest for optimal diabetes control. Signals: I will review metabolic monitoring, with a particular emphasis on the new continuous glucose sensors, on the crucial role of models to enhance the interpretation of their time-series signals, and on the opportunities that they present for automation of diabetes control. Control: I will review control strategies that have been successfully employed in vivo or in silico, presenting a promise for the development of a future artificial pancreas and, in particular, I will discuss a modular architecture for building closed-loop control systems, including insulin delivery and patient safety supervision layers.
Water-vapor pressure control in a volume
Scialdone, J. J.
1978-01-01
The variation with time of the partial pressure of water in a volume that has openings to the outside environment and includes vapor sources was evaluated as a function of the purging flow and its vapor content. Experimental tests to estimate the diffusion of ambient humidity through openings and to validate calculated results were included. The purging flows required to produce and maintain a certain humidity in shipping containers, storage rooms, and clean rooms can be estimated with the relationship developed here. These purging flows are necessary to prevent the contamination, degradation, and other effects of water vapor on the systems inside these volumes.
Modeling of Cementitious Representative Volume Element with Additives
Shahzamanian, M. M.; Basirun, W. J.
CEMHYD3D has been employed to simulate the representative volume element (RVE) of cementitious systems (Type I cement) containing fly ash (Class F) through a voxel-based finite element analysis (FEA) approach. Three-dimensional microstructures composed of voxels are generated for a heterogeneous cementitious material consisting of various constituent phases. The primary focus is to simulate a cementitious RVE containing fly ash and to present the homogenized macromechanical properties obtained from its analysis. Simple kinematic uniform boundary conditions as well as periodic boundary conditions were imposed on the RVE to obtain the principal and shear moduli. Our current work considers the effect of fly ash percentage on the elastic properties based on the mass and volume replacements. RVEs with lengths of 50, 100 and 200μm at different degrees of hydration are generated, and the elastic properties are modeled and simulated. In general, the elastic properties of a cementitious RVE with fly ash replacement for cement based on mass and volume differ from each other. Moreover, the finite element (FE) mesh density effect is studied. Results indicate that mechanical properties decrease with increasing mesh density.
Volume Dynamics Propulsion System Modeling for Supersonics Vehicle Research
Kopasakis, George; Connolly, Joseph W.; Paxson, Daniel E.; Ma, Peter
2010-01-01
Under the NASA Fundamental Aeronautics Program the Supersonics Project is working to overcome the obstacles to supersonic commercial flight. The proposed vehicles are long slim body aircraft with pronounced aero-servo-elastic modes. These modes can potentially couple with propulsion system dynamics; leading to performance challenges such as aircraft ride quality and stability. Other disturbances upstream of the engine generated from atmospheric wind gusts, angle of attack, and yaw can have similar effects. In addition, for optimal propulsion system performance, normal inlet-engine operations are required to be closer to compressor stall and inlet unstart. To study these phenomena an integrated model is needed that includes both airframe structural dynamics as well as the propulsion system dynamics. This paper covers the propulsion system component volume dynamics modeling of a turbojet engine that will be used for an integrated vehicle Aero-Propulso-Servo-Elastic model and for propulsion efficiency studies.
Finite volume model for two-dimensional shallow environmental flow
Simoes, F.J.M.
2011-01-01
This paper presents the development of a two-dimensional, depth integrated, unsteady, free-surface model based on the shallow water equations. The development was motivated by the desire of balancing computational efficiency and accuracy by selective and conjunctive use of different numerical techniques. The base framework of the discrete model uses Godunov methods on unstructured triangular grids, but the solution technique emphasizes the use of a high-resolution Riemann solver where needed, switching to a simpler and computationally more efficient upwind finite volume technique in the smooth regions of the flow. Explicit time marching is accomplished with strong stability preserving Runge-Kutta methods, with additional acceleration techniques for steady-state computations. A simplified mass-preserving algorithm is used to deal with wet/dry fronts. Application of the model is made to several benchmark cases that show the interplay of the diverse solution techniques.
Extraction and LOD control of colored interval volumes
Miyamura, Hiroko N.; Takeshima, Yuriko; Fujishiro, Issei; Saito, Takafumi
2005-03-01
Interval volume serves as a generalized isosurface and represents a three-dimensional subvolume for which the associated scalar filed values lie within a user-specified closed interval. In general, it is not an easy task for novices to specify the scalar field interval corresponding to their ROIs. In order to extract interval volumes from which desirable geometric features can be mined effectively, we propose a suggestive technique which extracts interval volumes automatically based on the global examination of the field contrast structure. Also proposed here is a simplification scheme for decimating resultant triangle patches to realize efficient transmission and rendition of large-scale interval volumes. Color distributions as well as geometric features are taken into account to select best edges to be collapsed. In addition, when a user wants to selectively display and analyze the original dataset, the simplified dataset is restructured to the original quality. Several simulated and acquired datasets are used to demonstrate the effectiveness of the present methods.
Comparison of Moving Boundary and Finite-Volume Heat Exchanger Models in the Modelica Language
Adriano Desideri
2016-05-01
Full Text Available When modeling low capacity energy systems, such as a small size (5–150 kWel organic Rankine cycle unit, the governing dynamics are mainly concentrated in the heat exchangers. As a consequence, the accuracy and simulation speed of the higher level system model mainly depend on the heat exchanger model formulation. In particular, the modeling of thermo-flow systems characterized by evaporation or condensation requires heat exchanger models capable of handling phase transitions. To this aim, the finite volume (FV and the moving boundary (MB approaches are the most widely used. The two models are developed and included in the open-source ThermoCycle Modelica library. In this contribution, a comparison between the two approaches is presented. An integrity and accuracy test is designed to evaluate the performance of the FV and MB models during transient conditions. In order to analyze how the two modeling approaches perform when integrated at a system level, two organic Rankine cycle (ORC system models are built using the FV and the MB evaporator model, and their responses are compared against experimental data collected on an 11 kWel ORC power unit. Additionally, the effect of the void fraction value in the MB evaporator model and of the number of control volumes (CVs in the FV one is investigated. The results allow drawing general guidelines for the development of heat exchanger dynamic models involving two-phase flows.
Simple Models for Process Control
Gorez, R.; Klán, Petr
2011-01-01
Roč. 22, č. 2 (2011), s. 58-62 ISSN 0929-2268 Institutional research plan: CEZ:AV0Z10300504 Keywords : process model s * PID control * second order dynamics Subject RIV: JB - Sensors, Measurment, Regulation
Weisburd, Melvin I.
The Field Operations and Enforcement Manual for Air Pollution Control, Volume II, explains in detail the following: technology of source control, modification of operations, particulate control equipment, sulfur dioxide removal systems for power plants, and control equipment for gases and vapors; inspection procedures for general sources, fuel…
Stormwater Volume Control to Prevent Increases in Lake Flooding and Dam Failure Risk
Potter, K. W.
2017-12-01
Urban expansion is not often considered a major factor contributing to dam failure. But if urbanization occurs without mitigation of the hydrologic impacts, the risk of dam failure will increase. Of particular concern are increases in the volume of storm runoff resulting from increases in the extent of impervious surfaces. Storm runoff volumes are not regulated for much the U.S, and where they are, the required control is commonly less than 100%. Unmitigated increases in runoff volume due to urbanization can pose a risk to dams. A recent technical advisory committee of Dane County has recommended that the county require 100% control of stormwater volumes for new developments. The primary motivation was to prevent increases in the water levels in the Yahara Lakes, slowly draining lakes that are highly sensitive to runoff volume. The recommendations included the use of "volume trading" to achieve efficient compliance. Such recommendations should be considered for other slowly draining lakes, including those created by artificial structures.
Controlling thermal deformation by using composite materials having variable fiber volume fraction
Bouremana, M.; Tounsi, A.; Kaci, A.; Mechab, I.
2009-01-01
In application, many thin structural components such as beams, plates and shells experience a through-thickness temperature variation. This temperature variation can produce both an in-plane expansion and an out-of-plane (bending) curvature. Given that these thin components interact with or connect to other components, we often wish to minimize the thermal deformation or match the thermal deformation of another component. This is accomplished by using a composite whose fibers have a negative axial thermal expansion coefficient. By varying the fiber volume fraction within a symmetric laminated beam to create a functionally graded material (FGM), certain thermal deformations can be controlled or tailored. Specifically, a beam can be designed which does not curve under a steady-state through-thickness temperature variation. Continuous gradation of the fiber volume fraction in the FGM layer is modelled in the form of a mth power polynomial of the coordinate axis in thickness direction of the beam. The beam results are independent of the actual temperature values, within the limitations of steady-state heat transfer and constant material properties. The influence of volume fiber fraction distributions are studied to match or eliminate an in-plane expansion coefficient, or to match a desired axial stiffness. Combining two fiber types to create a hybrid FGM can offer desirable increase in axial and bending stiffness while still retaining the useful thermal deformation behavior.
Rajagopalan Parameshwaran
2008-01-01
Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.
Fixed site neutralization model programmer's manual. Volume 1
Engi, D.; Chapman, L.; Judnick, W.; Blum, R.; Broegler, L.; Lenz, J.; Weinthraub, A.; Ballard, D.
1979-12-01
The Fixed Site Neutralization Model (FSNM) is a stochastic, time-stepped simulation of an engagement process whereby an adversary force attempts to steal or sabotage sensitive (e.g., nuclear) materials being guarded by a security force on a fixed site and a response force that is off-site. FSNM will assist regulatory bodies of the US Government in evaluating fixed site physical protection systems at various installations in a variety of scenarios. Most data input to the Fixed Site Neutralization Model are in binary form. The user's data are transformed into binary form by two supporting modules, the Data Preprocessor (DPP) and the Plex Preprocessor (PPP). Both preprocessors and the FSNM itself are written in FORTRAN. This volume of the program maintenance program contains: introduction, logic descriptions, PLEX data structure, PLEX records, dictionaries, and error conditions and comments
Development of modelling and forecasting in geology (Volume 4)
Courbouleix, S.; Colleau, A.; Defaut, B.; Fourniguet, J.; Peaudecerf, P.
1990-01-01
To access the long-term safety of radioactive waste disposal systems, validation of predictive models is essential and large efforts should be given to barriers, particularly geologic barriers. This work appears in the form of four volumes, the subject of the fourth part is described below. The purpose of this study is to find actual climates which can represent past climates in Europe, during Plio-Quaternary Palynology technics is the most adapted to restore ancient climates. A climatic index, Q n is defined as a function of yearly rainfalls, monthly extreme temperatures and aridity. A climatic diagram is built with climatic index Q n along X axis and a function of the yearly mean temperature along Y axis. This original method can ensure vegetation determination from climate and vice versa. Erosion and Weathering values may be determined after model calibration. 23 figs., 21 refs
Annual Conference on Manual Control (20th) Held in California on June 12 - 14, 1984. Volume 1
1984-06-14
Semisupine Pilot", Avimtion Space and Environmental Medicine , vol. 49, No. 1, pp. 304-317, January, 1978. [5] Levison, W.H., "Model For Human Controller...Performance in Vibration Environment", Aviation Space and Environmental Medicine , vol. 49, No. 1, pp. 321-327, January, 1978. [6] Repperger, D. W...Schwartz, Anthony C. Stein, Raymond E. Magdaleno, and Jeffrey R. Hogue, Effects of Alcohol and Marihuana on Driver Control Behavior. Volume I: Laboratory
Nonlinear Control of Heartbeat Models
Witt Thanom
2011-02-01
Full Text Available This paper presents a novel application of nonlinear control theory to heartbeat models. Existing heartbeat models are investigated and modified by incorporating the control input as a pacemaker to provide the control channel. A nonlinear feedback linearization technique is applied to force the output of the systems to generate artificial electrocardiogram (ECG signal using discrete data as the reference inputs. The synthetic ECG may serve as a flexible signal source to assess the effectiveness of a diagnostic ECG signal-processing device.
Wind Farms: Modeling and Control
Soleimanzadeh, Maryam
2012-01-01
is minimized. The controller is practically feasible. Yet, the results on load reduction in this approach are not very significant. In the second strategy, the wind farm control problem has been divided into below rated and above rated wind speed conditions. In the above rated wind speed pitch angle and power....... Distributed controller design commences with formulating the problem, where a structured matrix approach has been put in to practice. Afterwards, an H2 control problem is implemented to obtain the controller dynamics for a wind farm such that the structural loads on wind turbines are minimized.......The primary purpose of this work is to develop control algorithms for wind farms to optimize the power production and augment the lifetime of wind turbines in wind farms. In this regard, a dynamical model for wind farms was required to be the basis of the controller design. In the first stage...
Reflexion and control mathematical models
Novikov, Dmitry A
2014-01-01
This book is dedicated to modern approaches to mathematical modeling of reflexive processes in control. The authors consider reflexive games that describe the gametheoretical interaction of agents making decisions based on a hierarchy of beliefs regarding (1) essential parameters (informational reflexion), (2) decision principles used by opponents (strategic reflexion), (3) beliefs about beliefs, and so on. Informational and reflexive equilibria in reflexive games generalize a series of well-known equilibrium concepts in noncooperative games and models of collective behavior. These models allow posing and solving the problems of informational and reflexive control in organizational, economic, social and other systems, in military applications, etc. (the interested reader will find in the book over 30 examples of possible applications in these fields) and describing uniformly many psychological/sociological phenomena connected with reflexion, viz., implicit control, informational control via the mass media, re...
Global nuclear material control model
Dreicer, J.S.; Rutherford, D.A.
1996-01-01
The nuclear danger can be reduced by a system for global management, protection, control, and accounting as part of a disposition program for special nuclear materials. The development of an international fissile material management and control regime requires conceptual research supported by an analytical and modeling tool that treats the nuclear fuel cycle as a complete system. Such a tool must represent the fundamental data, information, and capabilities of the fuel cycle including an assessment of the global distribution of military and civilian fissile material inventories, a representation of the proliferation pertinent physical processes, and a framework supportive of national or international perspective. They have developed a prototype global nuclear material management and control systems analysis capability, the Global Nuclear Material Control (GNMC) model. The GNMC model establishes the framework for evaluating the global production, disposition, and safeguards and security requirements for fissile nuclear material
DOE Fundamentals Handbook: Instrumentation and Control, Volume 1
1992-06-01
The Instrumentation and Control Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of instrumentation and control systems. The handbook includes information on temperature, pressure, flow, and level detection systems; position indication systems; process control systems; and radiation detection principles. This information will provide personnel with an understanding of the basic operation of various types of DOE nuclear facility instrumentation and control systems
DOE Fundamentals Handbook: Instrumentation and Control, Volume 2
1992-06-01
The Instrumentation and Control Fundamentals Handbook personnel, and the technical staff facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of instrumentation and control systems. The handbook includes information on temperature, pressure, flow, and level detection systems; position indication systems; process control systems; and radiation detection principles. This information will provide personnel with an understanding of the basic operation of various types of DOE nuclear facility instrumentation and control systems
DOE Fundamentals Handbook: Instrumentation and Control, Volume 1
1992-06-01
The Instrumentation and Control Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of instrumentation and control systems. The handbook includes information on temperature, pressure, flow, and level detection systems; position indication systems; process control systems; and radiation detection principles. This information will provide personnel with an understanding of the basic operation of various types of DOE nuclear facility instrumentation and control systems.
Moore, James [U.S. Army Corps of Engineers - New York District 26 Federal Plaza, New York, New York 10278 (United States); Hays, David [U.S. Army Corps of Engineers - Kansas City District 601 E. 12th Street, Kansas City, Missouri 64106 (United States); Quinn, John; Johnson, Robert; Durham, Lisa [Argonne National Laboratory, Environmental Science Division 9700 S. Cass Ave., Argonne, Illinois 60439 (United States)
2013-07-01
As part of the ongoing remediation process at the Maywood Formerly Utilized Sites Remedial Action Program (FUSRAP) properties, Argonne National Laboratory (Argonne) assisted the U.S. Army Corps of Engineers (USACE) New York District by providing contaminated soil volume estimates for the main site area, much of which is fully or partially remediated. As part of the volume estimation process, an initial conceptual site model (ICSM) was prepared for the entire site that captured existing information (with the exception of soil sampling results) pertinent to the possible location of surface and subsurface contamination above cleanup requirements. This ICSM was based on historical anecdotal information, aerial photographs, and the logs from several hundred soil cores that identified the depth of fill material and the depth to bedrock under the site. Specialized geostatistical software developed by Argonne was used to update the ICSM with historical sampling results and down-hole gamma survey information for hundreds of soil core locations. The updating process yielded both a best guess estimate of contamination volumes and a conservative upper bound on the volume estimate that reflected the estimate's uncertainty. Comparison of model results to actual removed soil volumes was conducted on a parcel-by-parcel basis. Where sampling data density was adequate, the actual volume matched the model's average or best guess results. Where contamination was un-characterized and unknown to the model, the actual volume exceeded the model's conservative estimate. Factors affecting volume estimation were identified to assist in planning further excavations. (authors)
Knaup, Courtney; Mavroidis, Panayiotis; Stathakis, Sotirios; Smith, Mark; Swanson, Gregory; Papanikolaou, Niko
2011-09-01
This study evaluates low dose-rate brachytherapy (LDR) prostate plans to determine the biological effect of dose degradation due to prostate volume changes. In this study, 39 patients were evaluated. Pre-implant prostate volume was determined using ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1(®)) to create treatment plans using (103)Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. From the pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP) were determined using the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. The prostate volume changed between pre and post implant image sets ranged from -8% to 110%. TCP and the mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreases to the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose. A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined that patients with a small prostates were more likely to suffer TCP decrease. The biological effect of post operative prostate growth due to operative trauma in LDR was evaluated using the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volume post-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.
Modeling the spatial distribution of the parameters of the coolant in the reactor volume
Nikonov, S.P.
2011-01-01
In this paper the approach to the question about the spatial distribution of the parameters of the coolant in-reactor volume. To describe the in-core space is used specially developed preprocessor. When the work of the preprocessor in the first place, is recreated on the basis of available information (mostly-the original drawings) with high accuracy three-dimensional description of the structures of the reactor volume and, secondly, are prepared on this basis blocks input to the nodal system code improved estimate ATHLET, allows to take into account the hydrodynamic interaction between the spatial control volumes. As an example the special case of solutions of international standard problem on the reconstruction of the transition process in the third unit of the Kalinin nuclear power plant, due to the shutdown of one of the four Main Coolant Pumps in operation at the rated capacity (first download). Model-core area consists of approximately 58 000 control volumes and spatial relationships. It shows the influence of certain structural units of the core to the distribution of the mass floe rate of its height. It is detected a strong cross-flow coolant in the area over the baffle. Moreover, we study the distribution of the coolant temperature at the assembly head of WWER-1000 reactor. It is shown that in the region of the top of the assembly head, where we have installation of thermocouples, the flow coolant for internal assemblies core is formed by only from guide channel Reactor control and protected system Control rod flow, or a mixture of the guide channel flow and flow from the area in front of top grid head assembly (the peripheral assemblies). It is shown that the magnitude of the flow guide channels affects not only the position of control rods, but also the presence of a particular type of measuring channels (Self powered neutron detector sensors or Temperature control sensors) in the cassette. (Author)
Models for estimation of tree volume in the miombo woodlands of ...
Volume of trees is an important parameter in forest management, but only volume models with limited geographical and tree size coverage have previously been developed for Tanzanian miombo woodlands. This study developed models for estimating total, merchantable stem and branches volume applicable for the entire ...
INTRA/Mod3.2. Manual and Code Description. Volume I - Physical Modelling
Andersson, Jenny; Edlund, O.; Hermann, J.; Johansson, Lise-Lotte
1999-01-01
The INTRA Manual consists of two volumes. Volume I of the manual is a thorough description of the code INTRA, the Physical modelling of INTRA and the ruling numerical methods and volume II, the User's Manual is an input description. This document, the Physical modelling of INTRA, contains code characteristics, integration methods and applications
INTRA/Mod3.2. Manual and Code Description. Volume I - Physical Modelling
Andersson, Jenny; Edlund, O; Hermann, J; Johansson, Lise-Lotte
1999-01-01
The INTRA Manual consists of two volumes. Volume I of the manual is a thorough description of the code INTRA, the Physical modelling of INTRA and the ruling numerical methods and volume II, the User`s Manual is an input description. This document, the Physical modelling of INTRA, contains code characteristics, integration methods and applications
Anon.
1994-01-01
The Fifth Annual Environmental, Safety and Health Conference and Exhibition for the oil, gas and petrochemical industries was held January 25--27, 1994 in Houston, Texas. The objective of this conference was to provide a multidisciplinary forum dealing with state-of-the-art environmental and safety issues. This volume focuses on the following: emergency response and spill control; remediation; and health and safety issues. Individual papers have been processed separately for inclusion in the appropriate data bases
Volume-based geometric modeling for radiation transport calculations
Li, Z.; Williamson, J.F.
1992-01-01
Accurate theoretical characterization of radiation fields is a valuable tool in the design of complex systems, such as linac heads and intracavitary applicators, and for generation of basic dose calculation data that is inaccessible to experimental measurement. Both Monte Carlo and deterministic solutions to such problems require a system for accurately modeling complex 3-D geometries that supports ray tracing, point and segment classification, and 2-D graphical representation. Previous combinatorial approaches to solid modeling, which involve describing complex structures as set-theoretic combinations of simple objects, are limited in their ease of use and place unrealistic constraints on the geometric relations between objects such as excluding common boundaries. A new approach to volume-based solid modeling has been developed which is based upon topologically consistent definitions of boundary, interior, and exterior of a region. From these definitions, FORTRAN union, intersection, and difference routines have been developed that allow involuted and deeply nested structures to be described as set-theoretic combinations of ellipsoids, elliptic cylinders, prisms, cones, and planes that accommodate shared boundaries. Line segments between adjacent intersections on a trajectory are assigned to the appropriate region by a novel sorting algorithm that generalizes upon Siddon's approach. Two 2-D graphic display tools are developed to help the debugging of a given geometric model. In this paper, the mathematical basis of our system is described, it is contrasted to other approaches, and examples are discussed
Teaching Thermal Hydraulics and Numerical Methods: An Introductory Control Volume Primer
D. S. Lucas
2004-01-01
A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.com
Development of modelling and forecasting in geology. (Volume 1)
Afzali, H.; Fourniguet, J.; Peaudecerf, P.
1990-01-01
To assess the long-term safety of radioactive waste disposal systems, validation of predictive models is essential and large efforts should be given to barriers, particularly geologic barriers. This work appears in the form of four volumes, the subject of the first part is described below. Soils and rocks erosion depends upon climate, relief, lithology and human activities (deforesting). In the world, mechanical erosion is evaluated from 5 to 8 cm per 1000 years (mean denudation ratio). Rocks weathering solubilize chemical elements in the running water and rocks fracturation becomes more easily under erosion effects. Alteration front progress is 0.3-3 cm per 1000 years in temperate zones and 4-7 cm per 1000 years in tropical zones. 5 figs., 14 tabs., 80 refs
Electrochemical Control of pH in Nanoliter Volumes
Balakrishnan, Divya; Lamblin, Guillaume; Thomann, Jean Sebastien; Van Den Berg, Albert; Olthuis, Wouter; Pascual-García, César
2018-01-01
The electrochemical management of the proton concentration in miniaturized dimensions opens the way to control and parallelize multistep chemical reactions, but still it faces many challenges linked to the efficient proton generation and control of their diffusion. Here we present a device operated
A refined methodology for modeling volume quantification performance in CT
Chen, Baiyu; Wilson, Joshua; Samei, Ehsan
2014-03-01
The utility of CT lung nodule volume quantification technique depends on the precision of the quantification. To enable the evaluation of quantification precision, we previously developed a mathematical model that related precision to image resolution and noise properties in uniform backgrounds in terms of an estimability index (e'). The e' was shown to predict empirical precision across 54 imaging and reconstruction protocols, but with different correlation qualities for FBP and iterative reconstruction (IR) due to the non-linearity of IR impacted by anatomical structure. To better account for the non-linearity of IR, this study aimed to refine the noise characterization of the model in the presence of textured backgrounds. Repeated scans of an anthropomorphic lung phantom were acquired. Subtracted images were used to measure the image quantum noise, which was then used to adjust the noise component of the e' calculation measured from a uniform region. In addition to the model refinement, the validation of the model was further extended to 2 nodule sizes (5 and 10 mm) and 2 segmentation algorithms. Results showed that the magnitude of IR's quantum noise was significantly higher in structured backgrounds than in uniform backgrounds (ASiR, 30-50%; MBIR, 100-200%). With the refined model, the correlation between e' values and empirical precision no longer depended on reconstruction algorithm. In conclusion, the model with refined noise characterization relfected the nonlinearity of iterative reconstruction in structured background, and further showed successful prediction of quantification precision across a variety of nodule sizes, dose levels, slice thickness, reconstruction algorithms, and segmentation software.
Analysis of one-dimensional nonequilibrium two-phase flow using control volume method
Minato, Akihiko; Naitoh, Masanori
1987-01-01
A one-dimensional numerical analysis model was developed for prediction of rapid flow transient behavior involving boiling. This model was based on six conservation equations of time averaged parameters of gas and liquid behavior. These equations were solved by using a control volume method with an explicit time integration. This model did not use staggered mesh scheme, which had been commonly used in two-phase flow analysis. Because void fraction and velocity of each phase were defined at the same location in the present model, effects of void fraction on phase velocity calculation were treated directly without interpolation. Though non-staggered mesh scheme was liable to cause numerical instability with zigzag pressure field, stability was achieved by employing the Godunov method. In order to verify the present analytical model, Edwards' pipe blow down and Zaloudek's initially subcooled critical two-phase flow experiments were analyzed. Stable solutions were obtained for rarefaction wave propagation with boiling and transient two-phase flow behavior in a broken pipe by using this model. (author)
Murray, K. E.
2016-12-01
Management of produced fluids has become an important issue in Oklahoma because large volumes of saltwater are co-produced with oil and gas, and disposed into saltwater disposal wells at high rates. Petroleum production increased from 2009-2015, especially in central and north-central Oklahoma where the Mississippian and Hunton zones were redeveloped using horizontal wells and dewatering techniques that have led to a disproportional increase in produced water volumes. Improved management of co-produced water, including desalination for beneficial reuse and decreased saltwater disposal volumes, is only possible if spatial and temporal trends can be defined and related to the producing zones. It is challenging to quantify the volumes of co-produced water by region or production zone because co-produced water volumes are generally not reported. Therefore, the goal of this research is to estimate co-produced water volumes for 2008-present with an approach that can be replicated as petroleum production shifts to other regions. Oil and gas production rates from subsurface zones were multiplied by ratios of H2O:oil and H2O:gas for the respective zones. Initial H2O:oil and H2O:gas ratios were adjusted/calibrated, by zone, to maximize correlation of county-scale produced H2O estimates versus saltwater disposal volumes from 2013-2015. These calibrated ratios were then used to compute saltwater disposal volumes from 2008-2012 because of apparent data gaps in reported saltwater disposal volumes during that timeframe. This research can be used to identify regions that have the greatest need for produced water treatment systems. The next step in management of produced fluids is to explore optimal energy-efficient strategies that reduce deleterious effects.
Modeled Urea Distribution Volume and Mortality in the HEMO Study
Greene, Tom; Depner, Thomas A.; Levin, Nathan W.; Chertow, Glenn M.
2011-01-01
Summary Background and objectives In the Hemodialysis (HEMO) Study, observed small decreases in achieved equilibrated Kt/Vurea were noncausally associated with markedly increased mortality. Here we examine the association of mortality with modeled volume (Vm), the denominator of equilibrated Kt/Vurea. Design, setting, participants, & measurements Parameters derived from modeled urea kinetics (including Vm) and blood pressure (BP) were obtained monthly in 1846 patients. Case mix–adjusted time-dependent Cox regressions were used to relate the relative mortality hazard at each time point to Vm and to the change in Vm over the preceding 6 months. Mixed effects models were used to relate Vm to changes in intradialytic systolic BP and to other factors at each follow-up visit. Results Mortality was associated with Vm and change in Vm over the preceding 6 months. The association between change in Vm and mortality was independent of vascular access complications. In contrast, mortality was inversely associated with V calculated from anthropometric measurements (Vant). In case mix–adjusted analysis using Vm as a time-dependent covariate, the association of mortality with Vm strengthened after statistical adjustment for Vant. After adjustment for Vant, higher Vm was associated with slightly smaller reductions in intradialytic systolic BP and with risk factors for mortality including recent hospitalization and reductions in serum albumin concentration and body weight. Conclusions An increase in Vm is a marker for illness and mortality risk in hemodialysis patients. PMID:21511841
Lean Production Control at a High-Variety, Low-Volume Parts Manufacturer
Bokhorst, Jos A. C.; Slomp, Jannes
2010-01-01
Eaton Electric General Supplies, a parts manufacturing unit that supplies parts for Eaton's electrical business unit, implemented several lean control elements in its high-variety, low-volume production units. These control elements include a constant work-in-process mechanism to limit and control
Slomp, J.; Bokhorst, J.A.C.; Germs, R.
2009-01-01
Due to the success of lean manufacturing, many companies are interested in implementing a lean production control system. Lean production control principles include the levelling of production, the use of pull mechanisms and takt time control. These principles have mainly been applied in high volume
Aquatic Plant Control Research Program. Volume A-00-1
Kirk, James
2000-01-01
... at the Waterways Experiment Station. It is principally intended to be a forum whereby information pertaining to and resulting from the Corps of Engineers' nationwide Aquatic Plant Control Research Program (APCRP...
Callender, E. David; Steinbacher, Jody
1989-01-01
This is the fifth of five volumes on Information System Life-Cycle and Documentation Standards. This volume provides a well organized, easily used standard for management control and status reports used in monitoring and controlling the management, development, and assurance of informations systems and software, hardware, and operational procedures components, and related processes.
Replicating the Ice-Volume Signal of the Early Pleistocene with a Complex Earth System Model
Tabor, C. R.; Poulsen, C. J.; Pollard, D.
2013-12-01
Milankovitch theory proposes high-latitude summer insolation intensity paces the ice ages by controlling perennial snow cover amounts (Milankovitch, 1941). According to theory, the ~21 kyr cycle of precession should dominate the ice-volume records since it has the greatest influence on high-latitude summer insolation. Modeling experiments frequently support Milankovitch theory by attributing the majority of Northern Hemisphere high-latitude summer snowmelt to changes in the cycle of precession (e.g. Jackson and Broccoli, 2003). However, ice-volume proxy records, especially those of the Early Pleistocene (2.6-0.8 Ma), display variability with a period of ~41 kyr (Raymo and Lisiecki, 2005), indicative of insolation forcing from obliquity, which has a much smaller influence on summer insolation intensity than precession. Several hypotheses attempt to explain the discrepancies between Milkankovitch theory and the proxy records by invoking phenomena such as insolation gradients (Raymo and Nisancioglu, 2003), hemispheric offset (Raymo et al., 2006; Lee and Poulsen, 2009), and integrated summer energy (Huybers, 2006); however, all of these hypotheses contain caveats (Ruddiman, 2006) and have yet to be supported by modeling studies that use a complex GCM. To explore potential solutions to this '41 kyr problem,' we use an Earth system model composed of the GENESIS GCM and Land Surface model, the BIOME4 vegetation model, and the Pennsylvania State ice-sheet model. Using an asynchronous coupling technique, we run four idealized transient combinations of obliquity and precession, representing the orbital extremes of the Pleistocene (Berger and Loutre, 1991). Each experiment is run through several complete orbital cycles with a dynamic ice domain spanning North America and Greenland, and fixed preindustrial greenhouse-gas concentrations. For all orbital configurations, model results produce greater ice-volume spectral power at the frequency of obliquity despite significantly
Transaction-Based Building Controls Framework, Volume 1: Reference Guide
Somasundaram, Sriram [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pratt, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Akyol, Bora A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fernandez, Nicholas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Foster, Nikolas AF [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Somani, Abhishek [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steckley, Andrew C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Taylor, Zachary T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2014-12-01
This document proposes a framework concept to achieve the objectives of raising buildings’ efficiency and energy savings potential benefitting building owners and operators. We call it a transaction-based framework, wherein mutually-beneficial and cost-effective market-based transactions can be enabled between multiple players across different domains. Transaction-based building controls are one part of the transactional energy framework. While these controls realize benefits by enabling automatic, market-based intra-building efficiency optimizations, the transactional energy framework provides similar benefits using the same market -based structure, yet on a larger scale and beyond just buildings, to the society at large.
Evgrafov, Anton; Gregersen, Misha Marie; Sørensen, Mads Peter
2011-01-01
We present a convergence analysis of a cell-based finite volume (FV) discretization scheme applied to a problem of control in the coefficients of a generalized Laplace equation modelling, for example, a steady state heat conduction. Such problems arise in applications dealing with geometric optimal......, whereas the convergence of the coefficients happens only with respect to the "volumetric" Lebesgue measure. Additionally, depending on whether the stationarity conditions are stated for the discretized or the original continuous problem, two distinct concepts of stationarity at a discrete level arise. We...... provide characterizations of limit points, with respect to FV mesh size, of globally optimal solutions and two types of stationary points to the discretized problems. We illustrate the practical behaviour of our cell-based FV discretization algorithm on a numerical example....
Model Predictive Control for Integrating Traffic Control Measures
Hegyi, A.
2004-01-01
Dynamic traffic control measures, such as ramp metering and dynamic speed limits, can be used to better utilize the available road capacity. Due to the increasing traffic volumes and the increasing number of traffic jams the interaction between the control measures has increased such that local
Noise Controlled Synchronization in Potassium Coupled Neural Models
Postnov, D. E.; Ryazanova, L. S.; Zhirin, R. A.
2007-01-01
The paper applies biologically plausible models to investigate how noise input to small ensembles of neurons, coupled via the extracellular potassium concentration, can influence their firing patterns. Using the noise intensity and the volume of the extracellular space as control parameters, we......-temporal oscillations in neuronal ensembles....
Vectored Thrust Digital Flight Control for Crew Escape. Volume 2.
1985-12-01
no. 24. Lecrique, J., A. Rault, M. Tessier and J.L. Testud (1978), - "Multivariable Regulation of a Thermal Power Plant Steam Generator," presented...and Extended Kalman Observers," presented at the Conf. Decision and Control, San Diego, CA. Testud , J.L. (1977), Commande Numerique Multivariable du
Lirong Tan
2017-09-01
Full Text Available In this paper, we investigated the problem of computer-aided diagnosis of Attention Deficit Hyperactivity Disorder (ADHD using machine learning techniques. With the ADHD-200 dataset, we developed a Support Vector Machine (SVM model to classify ADHD patients from typically developing controls (TDCs, using the regional brain volumes as predictors. Conventionally, the volume of a brain region was considered to be an anatomical feature and quantified using structural magnetic resonance images. One major contribution of the present study was that we had initially proposed to measure the regional brain volumes using fMRI images. Brain volumes measured from fMRI images were denoted as functional volumes, which quantified the volumes of brain regions that were actually functioning during fMRI imaging. We compared the predictive power of functional volumes with that of regional brain volumes measured from anatomical images, which were denoted as anatomical volumes. The former demonstrated higher discriminative power than the latter for the classification of ADHD patients vs. TDCs. Combined with our two-step feature selection approach which integrated prior knowledge with the recursive feature elimination (RFE algorithm, our SVM classification model combining functional volumes and demographic characteristics achieved a balanced accuracy of 67.7%, which was 16.1% higher than that of a relevant model published previously in the work of Sato et al. Furthermore, our classifier highlighted 10 brain regions that were most discriminative in distinguishing between ADHD patients and TDCs. These 10 regions were mainly located in occipital lobe, cerebellum posterior lobe, parietal lobe, frontal lobe, and temporal lobe. Our present study using functional images will likely provide new perspectives about the brain regions affected by ADHD.
Evaluation of the effect of prostate volume change on tumor control probability in LDR brachytherapy
Courtney Knaup
2011-09-01
Full Text Available Purpose: This study evaluates low dose-rate brachytherapy (LDR prostate plans to determine the biological effectof dose degradation due to prostate volume changes. Material and methods: In this study, 39 patients were evaluated. Pre-implant prostate volume was determinedusing ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1® to create treatmentplans using 103Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. Fromthe pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP were determinedusing the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. Results: The prostate volume changed between pre and post implant image sets ranged from –8% to 110%. TCP andthe mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreasesto the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose.A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined thatpatients with a small prostates were more likely to suffer TCP decrease. Conclusions: The biological effect of post operative prostate growth due to operative trauma in LDR was evaluatedusing the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volumepost-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.
Design requirements for SRB production control system. Volume 4: Implementation
1981-01-01
The implementation plan which is presented was developed to provide the means for the successful implementation of the automated production control system. There are three factors which the implementation plan encompasses: detailed planning; phased implementation; and user involvement. The plan is detailed to the task level in terms of necessary activities as the system is developed, refined, installed, and tested. These tasks are scheduled, on a preliminary basis, over a two-and-one-half-year time frame.
Qingsong Xie
Full Text Available BACKGROUND: Standard-volume polyethylene glycol (PEG gut lavage solutions are safe and effective, but they require the consumption of large volumes of fluid. A new lower-volume solution of PEG plus ascorbic acid has been used recently as a preparation for colonoscopy. AIM: A meta-analysis was performed to compare the performance of low-volume PEG plus ascorbic acid with standard-volume PEG as bowel preparation for colonoscopy. STUDY: Electronic and manual searches were performed to identify randomized controlled trials (RCTs that compared the performance of low-volume PEG plus ascorbic acid with standard-volume PEG as bowel preparation for colonoscopy. After a methodological quality assessment and data extraction, the pooled estimates of bowel preparation efficacy during bowel cleansing, compliance with preparation, willingness to repeat the same preparation, and the side effects were calculated. We calculated pooled estimates of odds ratios (OR by fixed- and/or random-effects models. We also assessed heterogeneity among studies and the publication bias. RESULTS: Eleven RCTs were identified for analysis. The pooled OR for preparation efficacy during bowel cleansing and for compliance with preparation for low-volume PEG plus ascorbic acid were 1.08 (95% CI = 0.98-1.28, P = 0.34 and 2.23 (95% CI = 1.67-2.98, P<0.00001, respectively, compared with those for standard-volume PEG. The side effects of vomiting and nausea for low-volume PEG plus ascorbic acid were reduced relative to standard-volume PEG. There was no significant publication bias, according to a funnel plot. CONCLUSIONS: Low-volume PEG plus ascorbic acid gut lavage achieved non-inferior efficacy for bowel cleansing, is more acceptable to patients, and has fewer side effects than standard-volume PEG as a bowel preparation method for colonoscopy.
The integrated environmental control model
Rubin, E.S.; Berkenpas, M.B.; Kalagnanam, J.R. [Carnegie Mellon Univ., Pittsburgh, PA (United States)
1995-11-01
The capability to estimate the performance and cost of emission control systems is critical to a variety of planning and analysis requirements faced by utilities, regulators, researchers and analysts in the public and private sectors. The computer model described in this paper has been developed for DOe to provide an up-to-date capability for analyzing a variety of pre-combustion, combustion, and post-combustion options in an integrated framework. A unique capability allows performance and costs to be modeled probabilistically, which allows explicit characterization of uncertainties and risks.
Volume dependence of the melting temperature for alkali metals with Debye's model
Soma, T.; Kagaya, H.M.; Nishigaki, M.
1983-01-01
Using the volume dependence of the Grueneisen constant at higher temperatures, the volume effect on the melting temperature of alkali metals is studied by Lindeman's melting law and Debye's model. The obtained melting curve increases as a function of the compressed volume and shows the maximum of the melting point at the characteristic volume. The resultant data are qualitatively in agreement with the observed tendency for alkali metals. (author)
Minimally invasive lung volume reduction treated with bronchi occlusion emphysema model
Zhou Dayong; Shen Liming; Shen Junkang; Jin Yiqi; Chen Lei; Huang Xianchen
2007-01-01
Objective: To evaluate the efficacy and feasibility of the coil-and-glue method for the reduction of lung volume in rabbit emphysema model. Methods: Sixteen rabbits of emphysema model were divided into the occlusion group(n=10), in which both anterior bronchi were occluded using the coil-and- glue method, and the control group (n=6). The maximal static pressure of airway (P max ), peak expiratory flow (PEF), end-expiratory volume (EEV) and pressure of oxygen (PO 2 ) were measured at ante- emphysema, post-emphysema, 1 week and 4 week after occlusion respectively. The expectoration (or migration) of coil and collapse of lung were also investigated. Results: P max was (20.0±1.3) and (17.1± 1.4) cm H 2 O (1 cm H 2 O=0.098 kPa) in the occlusion group at ante-emphysema and post-emphysema respectively. P max was (19.2±1.4) cm H 2 O in the occlusion group in the 1 week after the occlusion, while (17.1±1.5)cm H 2 O in the control group (F=6.68, P max was (19.2±1.4) cm H 2 O in the occlusion group, while (16.6±1.2) cm H 2 O in the control group (F=12.10, P max , in the 1 week and 4 week after occlusion were higher than those at post-emphysema (P<0.01, respectively); EEV at post-emphysema was higher than that at ante-emphysema (P<0.01). Conclusion: Coil-and-glue occlusion method for lung volume reduction in rabbit emphysema model can improve the pulmonary function, which can be relatively long lasting. (authors)
Documentation for grants equal to tax model: Volume 3, Source code
Boryczka, M.K.
1986-01-01
The GETT model is capable of forecasting the amount of tax liability associated with all property owned and all activities undertaken by the US Department of Energy (DOE) in site characterization and repository development. The GETT program is a user-friendly, menu-driven model developed using dBASE III/trademark/, a relational data base management system. The data base for GETT consists primarily of eight separate dBASE III/trademark/ files corresponding to each of the eight taxes (real property, personal property, corporate income, franchise, sales, use, severance, and excise) levied by State and local jurisdictions on business property and activity. Additional smaller files help to control model inputs and reporting options. Volume 3 of the GETT model documentation is the source code. The code is arranged primarily by the eight tax types. Other code files include those for JURISDICTION, SIMULATION, VALIDATION, TAXES, CHANGES, REPORTS, GILOT, and GETT. The code has been verified through hand calculations
Mechanics and model-based control of advanced engineering systems
Irschik, Hans; Krommer, Michael
2014-01-01
Mechanics and Model-Based Control of Advanced Engineering Systems collects 32 contributions presented at the International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines, which took place in St. Petersburg, Russia in July 2012. The workshop continued a series of international workshops, which started with a Japan-Austria Joint Workshop on Mechanics and Model Based Control of Smart Materials and Structures and a Russia-Austria Joint Workshop on Advanced Dynamics and Model Based Control of Structures and Machines. In the present volume, 10 full-length papers based on presentations from Russia, 9 from Austria, 8 from Japan, 3 from Italy, one from Germany and one from Taiwan are included, which represent the state of the art in the field of mechanics and model based control, with particular emphasis on the application of advanced structures and machines.
Welding process modelling and control
Romine, Peter L.; Adenwala, Jinen A.
1993-01-01
The research and analysis performed, and software developed, and hardware/software recommendations made during 1992 in development of the PC-based data acquisition system for support of Welding Process Modeling and Control is reported. A need was identified by the Metals Processing Branch of NASA Marshall Space Flight Center, for a mobile data aquisition and analysis system, customized for welding measurement and calibration. Several hardware configurations were evaluated and a PC-based system was chosen. The Welding Measurement System (WMS) is a dedicated instrument, strictly for the use of data aquisition and analysis. Although the WMS supports many of the functions associated with the process control, it is not the intention for this system to be used for welding process control.
Multiple Model Approaches to Modelling and Control,
on the ease with which prior knowledge can be incorporated. It is interesting to note that researchers in Control Theory, Neural Networks,Statistics, Artificial Intelligence and Fuzzy Logic have more or less independently developed very similar modelling methods, calling them Local ModelNetworks, Operating......, and allows direct incorporation of high-level and qualitative plant knowledge into themodel. These advantages have proven to be very appealing for industrial applications, and the practical, intuitively appealing nature of the framework isdemonstrated in chapters describing applications of local methods...... to problems in the process industries, biomedical applications and autonomoussystems. The successful application of the ideas to demanding problems is already encouraging, but creative development of the basic framework isneeded to better allow the integration of human knowledge with automated learning...
Neuls, A.S.; Draper, W.E.; Koenig, R.A.; Newmyer, J.M.; Warner, C.L.
1982-11-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings specifications, calculations, and costs. It aids duplication of the process at other facilities
Neuls, A.S.; Draper, W.E.; Koenig, R.A.; Newmyer, J.M.; Warner, C.L.
1982-08-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawing, specifications, calculations, and costs. It aids duplication of the process at other facilities
Controlled air incinerator for radioactive waste. Volume II. Engineering design references manual
Koenig, R.A.; Draper, W.E.; Newmyer, J.M.; Warner, C.L.
1982-11-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities
Koenig, R.A.; Draper, W.E.; Newmyer, J.M.; Warner, C.L.
1982-10-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities.
Neuls, A.S.; Draper, W.E.; Koenig, R.A.; Newmyer, J.M.; Warner, C.L.
1982-08-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawing, specifications, calculations, and costs. It aids duplication of the process at other facilities.
Koenig, R.A.; Draper, W.E.; Newmyer, J.M.; Warner, C.L.
1982-10-01
This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities
1994-08-01
Volume I contains papers presented at the following sessions: high efficiency preparation; advanced physical coal cleaning; superclean emission systems; air toxics and mercury measurement and control workshop; and mercury measurement and control workshop. Selected papers have been processed for inclusion in the Energy Science and Technology Database.
Statistical shape modeling based renal volume measurement using tracked ultrasound
Pai Raikar, Vipul; Kwartowitz, David M.
2017-03-01
Autosomal dominant polycystic kidney disease (ADPKD) is the fourth most common cause of kidney transplant worldwide accounting for 7-10% of all cases. Although ADPKD usually progresses over many decades, accurate risk prediction is an important task.1 Identifying patients with progressive disease is vital to providing new treatments being developed and enable them to enter clinical trials for new therapy. Among other factors, total kidney volume (TKV) is a major biomarker predicting the progression of ADPKD. Consortium for Radiologic Imaging Studies in Polycystic Kidney Disease (CRISP)2 have shown that TKV is an early, and accurate measure of cystic burden and likely growth rate. It is strongly associated with loss of renal function.3 While ultrasound (US) has proven as an excellent tool for diagnosing the disease; monitoring short-term changes using ultrasound has been shown to not be accurate. This is attributed to high operator variability and reproducibility as compared to tomographic modalities such as CT and MR (Gold standard). Ultrasound has emerged as one of the standout modality for intra-procedural imaging and with methods for spatial localization has afforded us the ability to track 2D ultrasound in physical space which it is being used. In addition to this, the vast amount of recorded tomographic data can be used to generate statistical shape models that allow us to extract clinical value from archived image sets. In this work, we aim at improving the prognostic value of US in managing ADPKD by assessing the accuracy of using statistical shape model augmented US data, to predict TKV, with the end goal of monitoring short-term changes.
Preventive maintenance basis: Volume 30 -- Relays -- control. Final report
Worledge, D.; Hinchcliffe, G.
1998-07-01
US nuclear power plants are implementing preventive maintenance (PM) tasks with little documented basis beyond fundamental vendor information to support the tasks or their intervals. The Preventive Maintenance Basis project provides utilities with the technical basis for PM tasks and task intervals associated with 40 specific components such as valves, electric motors, pumps, and HVAC equipment. This document provides a program of preventive maintenance tasks suitable for application to control relays. The PM tasks that are recommended provide a cost-effective way to intercept the causes and mechanisms that lead to degradation and failure. They can be used in conjunction with material from other sources, to develop a complete PM program or to improve an existing program
Stepping motor control processor reference manual. Volume I
Holloway, F.W.; VanArsdall, P.J.; Suski, G.J.; Gant, R.G.; Rash, M.
1980-01-01
This manual is intended to serve several purposes. The first goal is to describe the capabilities and operation of the SMC processor package from an operator or user point of view. Secondly, the manual will describe in some detail the basic hardware elements and how they can be used effectively to implement a step motor control system. Practical information on the use, installation and checkout of the hardware set is presented in the following sections along with programming suggestions. Available related system software is described in this manual for reference and as an aid in understanding the system architecture. Section two presents an overview and operations manual of the SMC processor describing its composition and functional capabilities. Section three contains hardware descriptions in some detail for the LLL-designed hardware used in the SMC processor. Basic theory of operation and important features are explained
Ponschab, Martin; Schöchl, Herbert; Keibl, Claudia; Fischer, Henrik; Redl, Heinz; Schlimp, Christoph J
2015-10-06
Fluid resuscitation is a core stone of hemorrhagic shock therapy, and crystalloid fluids seem to be associated with lower mortality compared to colloids. However, as redistribution starts within minutes, it has been suggested to replace blood loss with a minimum of a three-fold amount of crystalloids. The hypothesis was that in comparison to high volume (HV), a lower crystalloid volume (LV) achieves a favorable coagulation profile and exerts sufficient haemodynamics in the acute phase of resuscitation. In 24 anaesthetized pigs, controlled arterial blood loss of 50 % of the estimated blood volume was either (n = 12) replaced with a LV (one-fold) or a HV (three-fold) volume of a balanced, acetated crystalloid solution at room temperature. Hemodynamic parameters, dilution effects and coagulation profile by standard coagulation tests and thromboelastometry at baseline and after resuscitation were determined in both groups. LV resuscitation increased MAP significantly less compared to the HV, 61 ± 7 vs. 82 ± 14 mmHg (p controlled blood loss, a one fold LV crystalloid replacement strategy is sufficient to adequately raise blood pressure up to a mean arterial pressure >50 mm Hg. The concept of damage control resuscitation (DCR) with permissive hypotension may be better met by using LV as compared to a three fold HV resuscitation strategy. High volume administration of an acetated balanced crystalloid does not lead to hyperchloraemic acidosis, but may negatively influence clinical parameters, such as higher blood pressure, lower body temperature and impaired coagulation parameters, which could potentially increase bleeding after trauma. Replacement of acute blood loss with just an equal amount of an acetated balanced crystalloid appears to be the preferential treatment strategy in the acute phase after controlled bleeding.
Ratajkiewicz, H.; Kierzek, R.; Raczkowski, M.; Hołodyńska-Kulas, A.; Łacka, A.; Wójtowicz, A.; Wachowiak, M.
2016-11-01
This study compared the effects of a proportionate spray volume (PSV) adjustment model and a fixed model (300 L/ha) on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha) when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop. (Author)
Henryk Ratajkiewicz
2016-08-01
Full Text Available This study compared the effects of a proportionate spray volume (PSV adjustment model and a fixed model (300 L/ha on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont. de Bary (PLB and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop.
Kawai, Hiroshi
2002-01-01
In the Chemical Volume Control System (CVCS) reactor primary coolant leakage incident, which occurred in Tsuruga-2 (4-loop PWR, 3,423 MWt, 1,160 MWe) on July 12, 1999, it took about 14 hours before the leakage isolation. The delayed leakage isolation and a large amount of leakage have become a social concern. Effective procedure modification was studied. Three betterments were proposed based on a qualitative analysis to reduce the pressure and temperature of the primary loop as fast as possible by the current plant facilities while maintaining enough subcooling of the primary loop. I analyzed the incident with RETRAN code in order to quantitatively evaluate the leakage reduction when these betterments are adopted. This paper is very new because it created a typical analysis method for PWR plant behavior during plant shutdown procedure which conventional RETRAN transient analyses rarely dealt with. Also the event time is very long. To carry out this analysis successfully, I devised new models such as an Residual Heat Removal System (RHR) model etc. and simplified parts of the conventional model. Based on the analysis results, I confirmed that leakage can be reduced by about 30% by adopting these betterments. Then the Japan Atomic Power Company (JAPC) modified the operational procedure for reactor primary coolant leakage events adopting these betterments. (author)
Imai, Takashi; Kovalenko, Andriy; Hirata, Fumio
2005-04-14
The three-dimensional reference interaction site model (3D-RISM) theory is applied to the analysis of hydration effects on the partial molar volume of proteins. For the native structure of some proteins, the partial molar volume is decomposed into geometric and hydration contributions using the 3D-RISM theory combined with the geometric volume calculation. The hydration contributions are correlated with the surface properties of the protein. The thermal volume, which is the volume of voids around the protein induced by the thermal fluctuation of water molecules, is directly proportional to the accessible surface area of the protein. The interaction volume, which is the contribution of electrostatic interactions between the protein and water molecules, is apparently governed by the charged atomic groups on the protein surface. The polar atomic groups do not make any contribution to the interaction volume. The volume differences between low- and high-pressure structures of lysozyme are also analyzed by the present method.
Automatic Flight Controller With Model Inversion
Meyer, George; Smith, G. Allan
1992-01-01
Automatic digital electronic control system based on inverse-model-follower concept being developed for proposed vertical-attitude-takeoff-and-landing airplane. Inverse-model-follower control places inverse mathematical model of dynamics of controlled plant in series with control actuators of controlled plant so response of combination of model and plant to command is unity. System includes feedback to compensate for uncertainties in mathematical model and disturbances imposed from without.
Design of a micro-irrigation system based on the control volume method
Chasseriaux G.
2006-01-01
Full Text Available A micro-irrigation system design based on control volume method using the back step procedure is presented in this study. The proposed numerical method is simple and consists of delimiting an elementary volume of the lateral equipped with an emitter, called « control volume » on which the conservation equations of the fl uid hydrodynamicʼs are applied. Control volume method is an iterative method to calculate velocity and pressure step by step throughout the micro-irrigation network based on an assumed pressure at the end of the line. A simple microcomputer program was used for the calculation and the convergence was very fast. When the average water requirement of plants was estimated, it is easy to choose the sum of the average emitter discharge as the total average fl ow rate of the network. The design consists of exploring an economical and effi cient network to deliver uniformly the input fl ow rate for all emitters. This program permitted the design of a large complex network of thousands of emitters very quickly. Three subroutine programs calculate velocity and pressure at a lateral pipe and submain pipe. The control volume method has already been tested for lateral design, the results from which were validated by other methods as fi nite element method, so it permits to determine the optimal design for such micro-irrigation network
Developments in model-based optimization and control distributed control and industrial applications
Grancharova, Alexandra; Pereira, Fernando
2015-01-01
This book deals with optimization methods as tools for decision making and control in the presence of model uncertainty. It is oriented to the use of these tools in engineering, specifically in automatic control design with all its components: analysis of dynamical systems, identification problems, and feedback control design. Developments in Model-Based Optimization and Control takes advantage of optimization-based formulations for such classical feedback design objectives as stability, performance and feasibility, afforded by the established body of results and methodologies constituting optimal control theory. It makes particular use of the popular formulation known as predictive control or receding-horizon optimization. The individual contributions in this volume are wide-ranging in subject matter but coordinated within a five-part structure covering material on: · complexity and structure in model predictive control (MPC); · collaborative MPC; · distributed MPC; · optimization-based analysis and desi...
Design and analysis of a dead volume control for a solar Stirling engine with induction generator
Beltrán-Chacon, Ricardo; Leal-Chavez, Daniel; Sauceda, D.; Pellegrini-Cervantes, Manuel; Borunda, Mónica
2015-01-01
In this work, a power generation system dish/Stirling with cavity receiver and an electrical induction generator was simulated. We propose a control system using a variable-dead-volume and analyze its influence on the mechanical performance. A system with a dead volume of 160 cm"3 was designed to control the power and speed of the engine considering annual insolation, mechanical properties of the heater and the limits of frequency and voltage for the systems interconnected to the electricity network. The designed system achieves net efficient solar conversion to electric of 23.38% at an irradiance of 975 W/m"2 and allows an annual increase of 18% of the useful electrical energy compared to a system without control. - Highlights: • Numerical simulation of a nitrogen charged solar Stirling engine for electric power generation. • Design and analysis of a dead volume control for performance increase and power modulation. • Effect of dead space on average working pressure and mass flow rate. • Comparison between dead volume and average pressure control methods. • Impact of Stirling engine control settings on annual generated electric power.
Choi, Hee Seok; Kim, Kwang Ki; Yoon, Yup Yoon; Seo, Hyung Suk
2009-01-01
To compare the corpus callosum (CC) area and brain volume among individuals with Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls (HC). To evaluate the relationship of CC area and brain volume in 111 subjects (M:F = 48:63; mean age, 56.9 years) without memory disturbance and 28 subjects (11:17; 66.7years) with memory disturbance. The 11 AD (3:8; 75.7 years), 17 MCI (8:9; 60.9 years) and 28 selected HC (11:17; 66.4 years) patients were investigated for comparison of their CC area and brain volume. A good positive linear correlation was found between CC area and brain volume in subjects without and with memory disturbance (r = 0.64 and 0.66, respectively, p 2 , 715.4 ± 107 cm3) were significantly smaller than in MCI patients (595.9 ± 108, 844.1 ± 85) and the HCs (563.2 ± 75, 818.9 ± 109) (p < 0.05). The CC area and brain volume were not significantly different between MCI patients and the HCs. The CC area was significantly correlated with brain volume. Both CC area and brain volume were significantly smaller in the AD patients
Li, Chang; Wang, Qing; Shi, Wenzhong; Zhao, Sisi
2018-05-01
The accuracy of earthwork calculations that compute terrain volume is critical to digital terrain analysis (DTA). The uncertainties in volume calculations (VCs) based on a DEM are primarily related to three factors: 1) model error (ME), which is caused by an adopted algorithm for a VC model, 2) discrete error (DE), which is usually caused by DEM resolution and terrain complexity, and 3) propagation error (PE), which is caused by the variables' error. Based on these factors, the uncertainty modelling and analysis of VCs based on a regular grid DEM are investigated in this paper. Especially, how to quantify the uncertainty of VCs is proposed by a confidence interval based on truncation error (TE). In the experiments, the trapezoidal double rule (TDR) and Simpson's double rule (SDR) were used to calculate volume, where the TE is the major ME, and six simulated regular grid DEMs with different terrain complexity and resolution (i.e. DE) were generated by a Gauss synthetic surface to easily obtain the theoretical true value and eliminate the interference of data errors. For PE, Monte-Carlo simulation techniques and spatial autocorrelation were used to represent DEM uncertainty. This study can enrich uncertainty modelling and analysis-related theories of geographic information science.
Takaishi, Tetsuya; Chen, Ting Ting
2016-08-01
We examine the relationship between trading volumes, number of transactions, and volatility using daily stock data of the Tokyo Stock Exchange. Following the mixture of distributions hypothesis, we use trading volumes and the number of transactions as proxy for the rate of information arrivals affecting stock volatility. The impact of trading volumes or number of transactions on volatility is measured using the generalized autoregressive conditional heteroscedasticity (GARCH) model. We find that the GARCH effects, that is, persistence of volatility, is not always removed by adding trading volumes or number of transactions, indicating that trading volumes and number of transactions do not adequately represent the rate of information arrivals.
Path modeling and process control
Høskuldsson, Agnar; Rodionova, O.; Pomerantsev, A.
2007-01-01
and having three or more stages. The methods are applied to a process control of a multi-stage production process having 25 variables and one output variable. When moving along the process, variables change their roles. It is shown how the methods of path modeling can be applied to estimate variables...... be performed regarding the foreseeable output property y, and with respect to an admissible range of correcting actions for the parameters of the next stage. In this paper the basic principles of path modeling is presented. The mathematics is presented for processes having only one stage, having two stages...... of the next stage with the purpose of obtaining optimal or almost optimal quality of the output variable. An important aspect of the methods presented is the possibility of extensive graphic analysis of data that can provide the engineer with a detailed view of the multi-variate variation in data....
Applying ARIMA model for annual volume time series of the Magdalena River
Gloria Amaris
2017-04-01
Conclusions: The simulated results obtained with the ARIMA model compared to the observed data showed a fairly good adjustment of the minimum and maximum magnitudes. This allows concluding that it is a good tool for estimating minimum and maximum volumes, even though this model is not capable of simulating the exact behaviour of an annual volume time series.
Cannula Tip With Integrated Volume Sensor for Rotary Blood Pump Control: Early-Stage Development.
Cysyk, Joshua; Newswanger, Ray; Popjes, Eric; Pae, Walter; Jhun, Choon-Sik; Izer, Jenelle; Weiss, William; Rosenberg, Gerson
2018-05-10
The lack of direct measurement of left ventricular unloading is a significant impediment to the development of an automatic speed control system for continuous-flow left ventricular assist devices (cf-LVADs). We have developed an inlet cannula tip for cf-LVADs with integrated electrodes for volume sensing based on conductance. Four platinum-iridium ring electrodes were installed into grooves on a cannula body constructed from polyetheretherketone (PEEK). A sinusoidal current excitation waveform (250 μA pk-pk, 50 kHz) was applied across one pair of electrodes, and the conductance-dependent voltage was sensed across the second pair of electrodes. The conductance catheter was tested in an acute ovine model (n = 3) in conjunction with the HeartMate II rotary blood pump to provide circulatory support and unload the ventricle. Echocardiography was used to measure ventricular size during pump support for verification for the conductance measurements. The conductance measurements correlated linearly with the echocardiography dimension measurements more than the full range of pump support from minimum support to suction. This cannula tip will enable the development of automatic control systems to optimize pump support based on a real-time measurement of ventricular size.
Ioannou, P. Zhang, Y. & Zhao, Y.
2017-01-01
This report presents the work performed in collaboration with University of California, Riverside (UCR) as part of a project to University of California, Davis funded by the California Energy Commission (CEC). The aim of the project is to research intelligent traffic control strategies, which will
Development and Analysis of Volume Multi-Sphere Method Model Generation using Electric Field Fitting
Ingram, G. J.
Electrostatic modeling of spacecraft has wide-reaching applications such as detumbling space debris in the Geosynchronous Earth Orbit regime before docking, servicing and tugging space debris to graveyard orbits, and Lorentz augmented orbits. The viability of electrostatic actuation control applications relies on faster-than-realtime characterization of the electrostatic interaction. The Volume Multi-Sphere Method (VMSM) seeks the optimal placement and radii of a small number of equipotential spheres to accurately model the electrostatic force and torque on a conducting space object. Current VMSM models tuned using force and torque comparisons with commercially available finite element software are subject to the modeled probe size and numerical errors of the software. This work first investigates fitting of VMSM models to Surface-MSM (SMSM) generated electrical field data, removing modeling dependence on probe geometry while significantly increasing performance and speed. A proposed electric field matching cost function is compared to a force and torque cost function, the inclusion of a self-capacitance constraint is explored and 4 degree-of-freedom VMSM models generated using electric field matching are investigated. The resulting E-field based VMSM development framework is illustrated on a box-shaped hub with a single solar panel, and convergence properties of select models are qualitatively analyzed. Despite the complex non-symmetric spacecraft geometry, elegantly simple 2-sphere VMSM solutions provide force and torque fits within a few percent.
2014-03-01
This study resulted in the development of the GASCAP model (the Greenhouse Gas Assessment : Spreadsheet for Transportation Capital Projects). This spreadsheet model provides a user-friendly interface for determining the greenhouse gas (GHG) emissions...
Modelling of Evaporator in Waste Heat Recovery System using Finite Volume Method and Fuzzy Technique
Jahedul Islam Chowdhury
2015-12-01
Full Text Available The evaporator is an important component in the Organic Rankine Cycle (ORC-based Waste Heat Recovery (WHR system since the effective heat transfer of this device reflects on the efficiency of the system. When the WHR system operates under supercritical conditions, the heat transfer mechanism in the evaporator is unpredictable due to the change of thermo-physical properties of the fluid with temperature. Although the conventional finite volume model can successfully capture those changes in the evaporator of the WHR process, the computation time for this method is high. To reduce the computation time, this paper develops a new fuzzy based evaporator model and compares its performance with the finite volume method. The results show that the fuzzy technique can be applied to predict the output of the supercritical evaporator in the waste heat recovery system and can significantly reduce the required computation time. The proposed model, therefore, has the potential to be used in real time control applications.
Transportation Sector Model of the National Energy Modeling System. Volume 2 -- Appendices: Part 3
NONE
1998-01-01
This Appendix consists of two unpublished reports produced by Energy and Environmental Analysis, Inc., under contract to Oak Ridge National Laboratory. These two reports formed the basis for the subsequent development of the Fuel Economy Model described in Volume 1. They are included in order to document more completely the efforts undertaken to construct a comprehensive model of automobile fuel economy. The supplemental reports are as follows: Supplement 1--Documentation Attributes of Technologies to Improve Automotive Fuel Economy; Supplement 2--Analysis of the Fuel Economy Boundary for 2010 and Comparison to Prototypes.
Diameter structure modeling and the calculation of plantation volume of black poplar clones
Andrašev Siniša
2004-01-01
Full Text Available A method of diameter structure modeling was applied in the calculation of plantation (stand volume of two black poplar clones in the section Aigeiros (Duby: 618 (Lux and S1-8. Diameter structure modeling by Weibull function makes it possible to calculate the plantation volume by volume line. Based on the comparison of the proposed method with the existing methods, the obtained error of plantation volume was less than 2%. Diameter structure modeling and the calculation of plantation volume by diameter structure model, by the regularity of diameter distribution, enables a better analysis of the production level and assortment structure and it can be used in the construction of yield and increment tables.
1994-08-01
Volume II contains papers presented at the following sessions: combustion 2000 session; advanced research and technology development session; commercial/industrial combustion systems session; alternative fuels utilization session; environmental control poster session; and advanced combustion technology poster session. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.
High-energy molecular lasers self-controlled volume-discharge lasers and applications
Apollonov, V V
2016-01-01
This book displays the physics and design of high-power molecular lasers. The lasers described are self-controlled volume-discharge lasers. The book explains self-sustained discharge lasers, self-initiated discharge lasers and technical approaches to laser design. Important topics discussed are laser efficiency, laser beam quality and electric field homogeneity. The book contains many new innovative applications.
Hattel, Jesper; Hansen, Preben
1995-01-01
This paper presents a novel control volume based FD method for solving the equilibrium equations in terms of displacements, i.e. the generalized Navier equations. The method is based on the widely used cv-FDM solution of heat conduction and fluid flow problems involving a staggered grid formulati....... The resulting linear algebraic equations are solved by line-Gauss-Seidel....
Control of Atmospheric Emissions in the Wood Pulping Industry, Volume 3.
Hendrickson, E. R.; And Others
Volume 3 contains chapters 9 through 13 of the final report on the control of atmospheric emissions in the wood pulping industry. These chapters deal with the following topics: sampling and analytical techniques; on-going research related to reduction of emissions; research and development recommendations; current industry investment and operating…
Weisburd, Melvin I.
The Field Operations and Enforcement Manual for Air Pollution Control, Volume III, explains in detail the following: inspection procedures for specific sources, kraft pulp mills, animal rendering, steel mill furnaces, coking operations, petroleum refineries, chemical plants, non-ferrous smelting and refining, foundries, cement plants, aluminum…
SCDAP/RELAP5/MOD 3.1 code manual: Damage progression model theory. Volume 2
Davis, K.L.
1995-06-01
The SCDAP/RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during a severe accident. The code models the coupled behavior of the reactor coolant system, the core, fission products released during a severe accident transient as well as large and small break loss of coolant accidents, operational transients such as anticipated transient without SCRAM, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits as much of a particular system to be modeled as necessary. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater conditioning systems. This volume contains detailed descriptions of the severe accident models and correlations. It provides the user with the underlying assumptions and simplifications used to generate and implement the basic equations into the code, so an intelligent assessment of the applicability and accuracy of the resulting calculation can be made
SCDAP/RELAP5/MOD 3.1 code manual: Damage progression model theory. Volume 2
Davis, K.L. [ed.; Allison, C.M.; Berna, G.A. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)] [and others
1995-06-01
The SCDAP/RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during a severe accident. The code models the coupled behavior of the reactor coolant system, the core, fission products released during a severe accident transient as well as large and small break loss of coolant accidents, operational transients such as anticipated transient without SCRAM, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits as much of a particular system to be modeled as necessary. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater conditioning systems. This volume contains detailed descriptions of the severe accident models and correlations. It provides the user with the underlying assumptions and simplifications used to generate and implement the basic equations into the code, so an intelligent assessment of the applicability and accuracy of the resulting calculation can be made.
Al Shehri, Abdullah M; El-Tahan, Mohamed R; Al Metwally, Roshdi; Qutub, Hatem; El Ghoneimy, Yasser F; Regal, Mohamed A; Zien, Haytham
2014-08-01
To test the effects of pressure-controlled (PCV) and volume-controlled (VCV) ventilation during one-lung ventilation (OLV) for thoracic surgery on right ventricular (RV) function. A prospective, randomized, double-blind, controlled, crossover study. A single university hospital. Fourteen pairs of consecutive patients scheduled for elective thoracotomy. Patients were assigned randomly to ventilate the dependent lung with PCV or VCV mode, each in a randomized crossover order using tidal volume of 6 mL/kg, I: E ratio 1: 2.5, positive end-expiratory pressure (PEEP) of 5 cm H2O and respiratory rate adjusted to maintain normocapnia. Intraoperative changes in RV function (systolic and early diastolic tricuspid annular velocity (TAV), end-systolic volume (ESV), end-diastolic volume (EDV) and fractional area changes (FAC)), airway pressures, compliance and oxygenation index were recorded. The use of PCV during OLV resulted in faster systolic (10.1±2.39 vs. 5.8±1.67 cm/s, respectively), diastolic TAV (9.2±1.99 vs. 4.6±1.42 cm/s, respectively) (prights reserved.
Chung, Beom Sun; Chung, Min Suk; Shin, Byeong Seok; Kwon, Koojoo
2018-02-19
The hand anatomy, including the complicated hand muscles, can be grasped by using computer-assisted learning tools with high quality two-dimensional images and three-dimensional models. The purpose of this study was to present up-to-date software tools that promote learning of stereoscopic morphology of the hand. On the basis of horizontal sectioned images and outlined images of a male cadaver, vertical planes, volume models, and surface models were elaborated. Software to browse pairs of the sectioned and outlined images in orthogonal planes and software to peel and rotate the volume models, as well as a portable document format (PDF) file to select and rotate the surface models, were produced. All of the software tools were downloadable free of charge and usable off-line. The three types of tools for viewing multiple aspects of the hand could be adequately employed according to individual needs. These new tools involving the realistic images of a cadaver and the diverse functions are expected to improve comprehensive knowledge of the hand shape. © 2018 The Korean Academy of Medical Sciences.
Stochastic processes, optimization, and control theory a volume in honor of Suresh Sethi
Yan, Houmin
2006-01-01
This edited volume contains 16 research articles. It presents recent and pressing issues in stochastic processes, control theory, differential games, optimization, and their applications in finance, manufacturing, queueing networks, and climate control. One of the salient features is that the book is highly multi-disciplinary. The book is dedicated to Professor Suresh Sethi on the occasion of his 60th birthday, in view of his distinguished career.
None
1980-06-01
These proceedings document the presentations given at the Second Environmental Control Symposium. Symposium presentations highlighted environmental control activities which span the entire DOE. Volume I contains papers relating to coal preparation, oil shales, coal combustion, advanced coal utilization (fluidized bed combustion, MHD generators, OCGT, fuel cells), coal gasification, coal liquefaction, and fossil resource extraction (enhanced recovery). Separate abstracts for individual papers are prepared for inclusion in the Energy Data Base. (DMC)
Documentation for Grants Equal to Tax model: Volume 1, Technical description
1986-01-01
A computerized model, the Grants Equal to Tax (GETT) model, was developed to assist in evaluating the amount of federal grant monies that would go to state and local jurisdictions under the provisions outlined in the Nuclear Waste Policy Act of 1982. The GETT model is capable of forecasting the amount of tax liability associated with all property owned and all activities undertaken by the US Department of Energy (DOE) in site characterization and repository development. The GETT program is a user-friendly, menu-driven model developed using dBASE III/trademark/, a relational data base management system. The data base for GETT consists primarily of eight separate dBASE III/trademark/ files corresponding to each of the eight taxes levied by state and local jurisdictions on business property and activity. Additional smaller files help to control model inputs and reporting options. Volume 1 of the GETT model documentation is a technical description of the program and its capabilities providing (1) descriptions of the data management system and its procedures; (2) formulas for calculating taxes (illustrated with flow charts); (3) descriptions of tax data base variables for the Deaf Smith County, Texas, Richton Dome, Mississippi, and Davis Canyon, Utah, salt sites; and (4) data inputs for the GETT model. 10 refs., 18 figs., 3 tabs
None
1976-12-01
This is the first in a series of reports evaluating environmental control technologies applicable to the coal-to-electricity process. The technologies are described and evaluated from an engineering and cost perspective based upon the best available information obtained from utility experience and development work in progress. Environmental control regulations and the health effects of pollutants are also reviewed. Emphasis is placed primarily upon technologies that are now in use. For SO/sub 2/ control, these include the use of low sulfur coal, cleaned coal, or flue-gas desulfurization systems. Electrostatic precipitators and fabric filters used for the control of particulate matter are analyzed, and combustion modifications for NO/sub x/ control are described. In each area, advanced technologies still in the development stage are described briefly and evaluated on the basis of current knowledge. Fluidized-bed combustion (FBC) is a near-term technology that is discussed extensively in the report. The potential for control of SO/sub 2/ and NO/sub x/ emissions by use of FBC is analyzed, as are the resulting solid waste disposal problems, cost estimates, and its potential applicability to electric utility systems. Volume II presents the detailed technology analyses complete with reference citations. This same material is given in condensed form in Volume I without references. A brief executive summary is also given in Volume I.
Wind turbine control and model predictive control for uncertain systems
Thomsen, Sven Creutz
as disturbance models for controller design. The theoretical study deals with Model Predictive Control (MPC). MPC is an optimal control method which is characterized by the use of a receding prediction horizon. MPC has risen in popularity due to its inherent ability to systematically account for time...
Volumes de calda e adjuvante no controle de plantas daninhas com glyphosate
Bueno,M.R.; Alves,G.S.; Paula,A.D.M.; Cunha,J.P.A.R.
2013-01-01
O sucesso de uma aplicação de herbicida está diretamente relacionado a uma boa deposição da calda no alvo, com o mínimo de perdas para o ambiente. Assim, o presente trabalho objetivou avaliar a deposição e o controle de plantas daninhas promovido pela aplicação de glyphosate em diferentes volumes de calda e com a adição do adjuvante nonil fenol etoxilado. O experimento foi conduzido em delineamento de blocos casualizados com quatro repetições, em esquema fatorial 3x2, sendo três volumes de ca...
Model predictive control using fuzzy decision functions
Kaymak, U.; Costa Sousa, da J.M.
2001-01-01
Fuzzy predictive control integrates conventional model predictive control with techniques from fuzzy multicriteria decision making, translating the goals and the constraints to predictive control in a transparent way. The information regarding the (fuzzy) goals and the (fuzzy) constraints of the
Mechanisms controlling the volume of pleural fluid and extravascular lung water
G. Miserocchi
2009-12-01
Full Text Available Pleural and interstitial lung fluid volumes are strictly controlled and maintained at the minimum thanks to the ability of lymphatics to match the increase in filtration rate. In the pleural cavity, fluid accumulation is easily accommodated by retraction of lung and chest wall (high compliance of the pleural space; the increase of lymph flow per unit increase in pleural fluid volume is high due to the great extension of the parietal lymphatic. However, for the lung interstitium, the increase in lymph flow to match increased filtration does not need to be so great. In fact, increased filtration only causes a minor increase in extravascular water volume (<10% due to a marked increase in interstitial pulmonary pressure (low compliance of the extracellular matrix which, in turn, buffers further filtration. Accordingly, a less extended lymphatic network is needed. The efficiency of lymphatic control is achieved through a high lymphatic conductance in the pleural fluid and through a low interstitial compliance for the lung interstitium. Fluid volume in both compartments is so strictly controlled that it is difficult to detect initial deviations from the physiological state; thus, a great physiological advantage turns to be a disadvantage on a clinical basis as it prevents an early diagnosis of developing disease.
Rodrigo Melo Gallindo
Full Text Available OBJECTIVE: To standardize a technique for ventilating rat fetuses with Congenital Diaphragmatic Hernia (CDH using a volume-controlled ventilator. METHODS: Pregnant rats were divided into the following groups: a control (C; b exposed to nitrofen with CDH (CDH; and c exposed to nitrofen without CDH (N-. Fetuses of the three groups were randomly divided into the subgroups ventilated (V and non-ventilated (N-V. Fetuses were collected on day 21.5 of gestation, weighed and ventilated for 30 minutes using a volume-controlled ventilator. Then the lungs were collected for histological study. We evaluated: body weight (BW, total lung weight (TLW, left lung weight (LLW, ratios TLW / BW and LLW / BW, morphological histology of the airways and causes of failures of ventilation. RESULTS: BW, TLW, LLW, TLW / BW and LLW / BW were higher in C compared with N- (p 0.05. The morphology of the pulmonary airways showed hypoplasia in groups N- and CDH, with no difference between V and N-V (p <0.05. The C and N- groups could be successfully ventilated using a tidal volume of 75 ìl, but the failure of ventilation in the CDH group decreased only when ventilated with 50 ìl. CONCLUSION: Volume ventilation is possible in rats with CDH for a short period and does not alter fetal or lung morphology.
Transportation Sector Model of the National Energy Modeling System. Volume 2 -- Appendices: Part 2
NONE
1998-01-01
The attachments contained within this appendix provide additional details about the model development and estimation process which do not easily lend themselves to incorporation in the main body of the model documentation report. The information provided in these attachments is not integral to the understanding of the model`s operation, but provides the reader with opportunity to gain a deeper understanding of some of the model`s underlying assumptions. There will be a slight degree of replication of materials found elsewhere in the documentation, made unavoidable by the dictates of internal consistency. Each attachment is associated with a specific component of the transportation model; the presentation follows the same sequence of modules employed in Volume 1. The following attachments are contained in Appendix F: Fuel Economy Model (FEM)--provides a discussion of the FEM vehicle demand and performance by size class models; Alternative Fuel Vehicle (AFV) Model--describes data input sources and extrapolation methodologies; Light-Duty Vehicle (LDV) Stock Model--discusses the fuel economy gap estimation methodology; Light Duty Vehicle Fleet Model--presents the data development for business, utility, and government fleet vehicles; Light Commercial Truck Model--describes the stratification methodology and data sources employed in estimating the stock and performance of LCT`s; Air Travel Demand Model--presents the derivation of the demographic index, used to modify estimates of personal travel demand; and Airborne Emissions Model--describes the derivation of emissions factors used to associate transportation measures to levels of airborne emissions of several pollutants.
Multiplicity Control in Structural Equation Modeling
Cribbie, Robert A.
2007-01-01
Researchers conducting structural equation modeling analyses rarely, if ever, control for the inflated probability of Type I errors when evaluating the statistical significance of multiple parameters in a model. In this study, the Type I error control, power and true model rates of famsilywise and false discovery rate controlling procedures were…
Variation in Measurements of Transtibial Stump Model Volume A Comparison of Five Methods
Bolt, A.; de Boer-Wilzing, V. G.; Geertzen, J. H. B.; Emmelot, C. H.; Baars, E. C. T.; Dijkstra, P. U.
Objective: To determine the right moment for fitting the first prosthesis, it is necessary to know when the volume of the stump has stabilized. The aim of this study is to analyze variation in measurements of transtibial stump model volumes using the water immersion method, the Design TT system, the
1987 Oak Ridge model conference: Proceedings: Volume 3, Health and safety
1987-01-01
See the abstract for Volume I for general information on the conference. Topics discussed in Volume III include the use of models in handling hazardous materials, communication at waste sites, asbestos, regulatory decisions, emergency planning, training programs, occupational hazards, and protection of subcontractors
Estimating tree bole volume using artificial neural network models for four species in Turkey.
Ozçelik, Ramazan; Diamantopoulou, Maria J; Brooks, John R; Wiant, Harry V
2010-01-01
Tree bole volumes of 89 Scots pine (Pinus sylvestris L.), 96 Brutian pine (Pinus brutia Ten.), 107 Cilicica fir (Abies cilicica Carr.) and 67 Cedar of Lebanon (Cedrus libani A. Rich.) trees were estimated using Artificial Neural Network (ANN) models. Neural networks offer a number of advantages including the ability to implicitly detect complex nonlinear relationships between input and output variables, which is very helpful in tree volume modeling. Two different neural network architectures were used and produced the Back propagation (BPANN) and the Cascade Correlation (CCANN) Artificial Neural Network models. In addition, tree bole volume estimates were compared to other established tree bole volume estimation techniques including the centroid method, taper equations, and existing standard volume tables. An overview of the features of ANNs and traditional methods is presented and the advantages and limitations of each one of them are discussed. For validation purposes, actual volumes were determined by aggregating the volumes of measured short sections (average 1 meter) of the tree bole using Smalian's formula. The results reported in this research suggest that the selected cascade correlation artificial neural network (CCANN) models are reliable for estimating the tree bole volume of the four examined tree species since they gave unbiased results and were superior to almost all methods in terms of error (%) expressed as the mean of the percentage errors. 2009 Elsevier Ltd. All rights reserved.
The spill prevention, control, and countermeasures (SPCC) plan for the Y-12 Plant. Volume 1
1992-08-01
This spill prevention, control and countermeasures (SPCC) Plan is divided into two volumes. Volume I addresses Y-12`s compliance with regulations pertinent to the content of SPCC Plans. Volume II is the SPCC Hazardous Material Storage Data Base, a detailed tabulation of facility-specific information and data on potential spill sources at the Y-12 Plant. Volume I follows the basic format and subject sequence specified in 40 CFR 112.7. This sequence is prefaced by three additional chapters, including this introduction and brief discussions of the Y-12 Plant`s background/environmental setting and potential spill source categories. Two additional chapters on containers and container storage areas and PCB and PCB storage for disposal facilities are inserted into the required sequence. The following required subjects are covered in this volume: Spill history, site drainage; secondary containment/diversion structures and equipment; contingency plans; notification and spill response procedures; facility drainage; bulk storage tanks; facility transfer operations, pumping, and in-plant processes; transfer stations (facility tank cars/tank tracks); inspections and records; security, and personnel, training, and spill prevention procedures.
Zhu, Yonghua; Jin, Xinqiao; Du, Zhimin; Fang, Xing
2015-01-01
The variable refrigerant flow (VRF) and variable air volume (VAV) combined air conditioning system can solve the problem of the VRF system in outdoor air ventilation while taking advantage of its high part load energy efficiency. Energy performance of the combined air conditioning system can also be optimized by joint control of both the VRF and the VAV parts. A model-based online optimal control strategy for the combined air conditioning system is presented. Simplified adaptive models of major components of the combined air conditioning system are firstly developed for predicting system performances. And a cost function in terms of energy consumption and thermal comfort is constructed. Genetic algorithm is used to search for the optimal control sets. The optimal control strategy is tested and evaluated through two case studies based on the simulation platform. Results show that the optimal strategy can effectively reduce energy consumption of the combined air conditioning system while maintaining acceptable thermal comfort. - Highlights: • A VRF and VAV combined system is proposed. • A model-based online optimal control strategy is proposed for the combined system. • The strategy can reduce energy consumption without sacrificing thermal comfort. • Novel simplified adaptive models are firstly developed for the VRF system
Volume calibration for nuclear materials control: ANSI N15.19-1989 and beyond
Liebetrau, A.M.
1994-03-01
Since the last IAEA International Safeguards Symposium, a revised standard for volume calibration methodology was issued in the United States. Because the new standard reflects the advent of high-precision volume measurement technology, it is significantly different from the earlier standard which it supersedes. The new standard outlines a unified data standardization model that applies to process tanks equipped with differential pressure measurement systems for determining liquid content. At the heart of the model is an algorithm to determine liquid height from pressure measurements that accounts for the major factors affecting the accuracy of those measurements. The standardization model also contains algorithms that adjust data from volumetric and gravimetric provers to a standard set of reference conditions. A key component of the standardization model is an algorithm to take account of temperature-induced dimensional changes in the tank. Improved methods for the statistical treatment of calibration data have also appeared since the last Safeguards Symposium. A statistical method of alignment has been introduced that employs a least-squares criterion to determine ''optimal'' alignment factors. More importantly, a statistical model has been proposed that yields plausible estimates of the variance of height and volume measurements when significant run-to-run differences are present in the calibration data. The new standardization model and statistical methods described here are being implemented in a portable, user-friendly software program for use by IAEA inspectors and statisticians. Perhaps these methods will eventually find their way into appropriate international standards
Model complexity control for hydrologic prediction
Schoups, G.; Van de Giesen, N.C.; Savenije, H.H.G.
2008-01-01
A common concern in hydrologic modeling is overparameterization of complex models given limited and noisy data. This leads to problems of parameter nonuniqueness and equifinality, which may negatively affect prediction uncertainties. A systematic way of controlling model complexity is therefore
Review of air quality modeling techniques. Volume 8
Rosen, L.C.
1977-01-01
Air transport and diffusion models which are applicable to the assessment of the environmental effects of nuclear, geothermal, and fossil-fuel electric generation are reviewed. The general classification of models and model inputs are discussed. A detailed examination of the statistical, Gaussian plume, Gaussian puff, one-box and species-conservation-of-mass models is given. Representative models are discussed with attention given to the assumptions, input data requirement, advantages, disadvantages and applicability of each
NATO Reference Mobility Model. Edition I. Users Guide. Volume I
1979-10-01
C TOTAL ERAKING FCRCE - SCIL /SLOPE/VEHICLE C --- ----.----------- C 275 R-2WJ58# VCLUIJE I PAGE A-103 APPEND-IX A - LISTING CF O.CFAt’ NRtPM C 1...sGCW vN1RAV ,SFTYPC 9TBF I- c r-------------------------~e e C tPAXIMUP BRAKING FCRCE * SCIL /SL OP E/V ENICLE/ DRIVER C --------------------- C C 1. VAR...CONTINUE GO TC 2160 ,ýObO IFl IST ,NE, 21 GC TG 2110i 317 R-20358, VOLUME I PAGE A-145 APPENDIX A - LISTING CF FRGG/iAM NAMM C 8. COARSE GRAINED SCIL IF
A discrete control model of PLANT
Mitchell, C. M.
1985-01-01
A model of the PLANT system using the discrete control modeling techniques developed by Miller is described. Discrete control models attempt to represent in a mathematical form how a human operator might decompose a complex system into simpler parts and how the control actions and system configuration are coordinated so that acceptable overall system performance is achieved. Basic questions include knowledge representation, information flow, and decision making in complex systems. The structure of the model is a general hierarchical/heterarchical scheme which structurally accounts for coordination and dynamic focus of attention. Mathematically, the discrete control model is defined in terms of a network of finite state systems. Specifically, the discrete control model accounts for how specific control actions are selected from information about the controlled system, the environment, and the context of the situation. The objective is to provide a plausible and empirically testable accounting and, if possible, explanation of control behavior.
Model predictive control for a thermostatic controlled system
Shafiei, Seyed Ehsan; Rasmussen, Henrik; Stoustrup, Jakob
2013-01-01
This paper proposes a model predictive control scheme to provide temperature set-points to thermostatic controlled cooling units in refrigeration systems. The control problem is formulated as a convex programming problem to minimize the overall operating cost of the system. The foodstuff temperat......This paper proposes a model predictive control scheme to provide temperature set-points to thermostatic controlled cooling units in refrigeration systems. The control problem is formulated as a convex programming problem to minimize the overall operating cost of the system. The foodstuff...
Langenberg, Rick van de; Dohmen, Amy J.C.; Bondt, Bert J. de; Nelemans, Patty J.; Baumert, Brigitta G.; Stokroos, Robert J.
2012-01-01
Purpose: The purpose of this study was to evaluate the control rate of vestibular schwannomas (VS) after treatment with linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) or radiotherapy (SRT) by using a validated volumetric measuring tool. Volume-based studies on prognosis after LINAC-based SRS or SRT for VS are reported scarcely. In addition, growth patterns and risk factors predicting treatment failure were analyzed. Materials and Methods: Retrospectively, 37 VS patients treated with LINAC based SRS or SRT were analyzed. Baseline and follow-up magnetic resonance imaging scans were analyzed with volume measurements on contrast enhanced T1-weighted magnetic resonance imaging. Absence of intervention after radiotherapy was defined as “no additional intervention group, ” absence of radiological growth was defined as “radiological control group. ” Significant growth was defined as a volume change of 19.7% or more, as calculated in a previous study. Results: The cumulative 4-year probability of no additional intervention was 96.4% ± 0.03; the 4-year radiological control probability was 85.4% ± 0.1). The median follow-up was 40 months. Overall, shrinkage was seen in 65%, stable VS in 22%, and growth in 13%. In 54% of all patients, transient swelling was observed. No prognostic factors were found regarding VS growth. Previous treatment and SRS were associated with transient swelling significantly. Conclusions: Good control rates are reported for LINAC based SRS or SRT in VS, in which the lower rate of radiological growth control is attributed to the use of the more sensitive volume measurements. Transient swelling after radiosurgery is a common phenomenon and should not be mistaken for treatment failure. Previous treatment and SRS were significantly associated with transient swelling.
Plant, Valerie; Limkemann, Ashley; Liebrecht, Loren; Blocher, Charles; Ferrada, Paula; Aboutanos, Michel; Mangino, Martin J
2016-12-01
Polyethylene glycol-20k (PEG-20k) is highly effective for low-volume resuscitation (LVR) by increasing tolerance to the low-volume state. In our rodent shock model, PEG-20k increased survival and expanded the "golden hour" 16-fold compared to saline. The molecular mechanism is largely attributed to normalizations in cell and tissue fluid shifts after low-flow ischemia resulting in efficient microvascular exchange. The objective of this study was to evaluate PEG-20k as an LVR solution for hemorrhagic shock in a preclinical model. Anesthetized male Yorkshire pigs (30-40 kg) were hemorrhaged to a mean arterial pressure (MAP) of 35 to 40 mm Hg. Once lactate reached 7 mmol/L, either saline (n = 5) or 10% PEG-20k (n = 5) was rapidly infused at 10% calculated blood volume. The primary outcome was LVR time, defined by the time from LVR administration to the time when lactate again reached 7 mmol/L. Other outcomes measured included MAP, heart rate, cardiac output, mixed venous oxygen saturation, splanchnic blood flow, and hemoglobin. Relative to saline, PEG-20k given after controlled hemorrhage increased LVR time by 16-fold, a conservative estimate given that the lactate never rose after LVR in the PEG-20k group. Survival was 80% for PEG-20k LVR compared to 0% for the saline controls (p the intravascular compartment. In a preclinical model of controlled hemorrhagic shock, PEG-20k-based LVR solution increased tolerance to the shock state 16-fold compared to saline. Polyethylene glycol-20k is a superior crystalloid for LVR that may increase safe transport times in the prehospital setting and find use in hospital emergency departments and operating rooms for patients awaiting volume replacement or normalization of cell, tissue, and compartment fluid volumes.
Tube Model Predictive Control with an Auxiliary Sliding Mode Controller
Miodrag Spasic
2016-07-01
Full Text Available This paper studies Tube Model Predictive Control (MPC with a Sliding Mode Controller (SMC as an auxiliary controller. It is shown how to calculate the tube widths under SMC control, and thus how much the constraints of the nominal MPC have to be tightened in order to achieve robust stability and constraint fulfillment. The analysis avoids the assumption of infinitely fast switching in the SMC controller.
Frey, H. Christopher [North Carolina State University, Raleigh, NC (United States); Rhodes, David S. [North Carolina State University, Raleigh, NC (United States)
1999-04-30
This is Volume 1 of a two-volume set of reports describing work conducted at North Carolina State University sponsored by Grant Number DE-FG05-95ER30250 by the U.S. Department of Energy. The title of the project is “Quantitative Analysis of Variability and Uncertainty in Acid Rain Assessments.” The work conducted under sponsorship of this grant pertains primarily to two main topics: (1) development of new methods for quantitative analysis of variability and uncertainty applicable to any type of model; and (2) analysis of variability and uncertainty in the performance, emissions, and cost of electric power plant combustion-based NOx control technologies. These two main topics are reported separately in Volumes 1 and 2.
VIPRE-01. a thermal-hydraulic analysis code for reactor cores. Volume 1. Mathematical modeling
Stewart, C.W.; Cuta, J.M.; Koontz, A.S.; Kelly, J.M.; Basehore, K.L.; George, T.L.; Rowe, D.S.
1983-04-01
VIPRE (Versatile Internals and Component Program for Reactors; EPRI) has been developed for nuclear power utility thermal-hydraulic analysis applications. It is designed to help evaluate nuclear reactor core safety limits including minimum departure from nucleate boiling ratio (MDNBR), critical power ratio (CPR), fuel and clad temperatures, and coolant state in normal operation and assumed accident conditions. This volume (Volume 1: Mathematical Modeling) explains the major thermal hydraulic models and supporting correlations in detail
None
1996-12-01
Volume VII of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the tritium transport model documentation. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.
Statistical Modeling of Ultrawideband Body-Centric Wireless Channels Considering Room Volume
Miyuki Hirose
2012-01-01
Full Text Available This paper presents the results of a statistical modeling of onbody ultrawideband (UWB radio channels for wireless body area network (WBAN applications. Measurements were conducted in five different rooms. A measured delay profile can be divided into two domains; in the first domain (04 ns has multipath components that are dominant and dependent on room volume. The first domain was modeled with a conventional power decay law model, and the second domain with a modified Saleh-Valenzuela model considering the room volume. Realizations of the impulse responses are presented based on the composite model and compared with the measured average power delay profiles.
Lanchester-Type Models of Warfare, Volume II
Taylor, James G.
1980-01-01
This monograph is a comprehensive treatist on Lanchester-type models of warfare, i.e. differential-equation models of attrition in force-on-force combat operations. Its goal is to provide both an introduction to and current-state-of-the-art overview of Lanchester-type models of warfare as well as a comprehensive and unified in-depth treatment of them. Both deterministic as well as stochastic models are considered. Such models have been widely used in the United States and elsewhere for the...
Modeling, robust and distributed model predictive control for freeway networks
Liu, S.
2016-01-01
In Model Predictive Control (MPC) for traffic networks, traffic models are crucial since they are used as prediction models for determining the optimal control actions. In order to reduce the computational complexity of MPC for traffic networks, macroscopic traffic models are often used instead of
Modelling and Control of a Mobile Robot
Christensen, Georg Kronborg
1998-01-01
In order to control a mobile robot, kinematic odels as well as dynamic models are required. This parer describes these basic models for an experimental mobile robot under construction at the Department of Control and Engineering Design. A description of a set of trajectory control rules is given...
Predictor-Based Model Reference Adaptive Control
Lavretsky, Eugene; Gadient, Ross; Gregory, Irene M.
2010-01-01
This paper is devoted to the design and analysis of a predictor-based model reference adaptive control. Stable adaptive laws are derived using Lyapunov framework. The proposed architecture is compared with the now classical model reference adaptive control. A simulation example is presented in which numerical evidence indicates that the proposed controller yields improved transient characteristics.
Basic Research on Adaptive Model Algorithmic Control
1985-12-01
Control Conference. Richalet, J., A. Rault, J.L. Testud and J. Papon (1978). Model predictive heuristic control: applications to industrial...pp.977-982. Richalet, J., A. Rault, J. L. Testud and J. Papon (1978). Model predictive heuristic control: applications to industrial processes
Can better modelling improve tokamak control?
Lister, J.B.; Vyas, P.; Ward, D.J.; Albanese, R.; Ambrosino, G.; Ariola, M.; Villone, F.; Coutlis, A.; Limebeer, D.J.N.; Wainwright, J.P.
1997-01-01
The control of present day tokamaks usually relies upon primitive modelling and TCV is used to illustrate this. A counter example is provided by the successful implementation of high order SISO controllers on COMPASS-D. Suitable models of tokamaks are required to exploit the potential of modern control techniques. A physics based MIMO model of TCV is presented and validated with experimental closed loop responses. A system identified open loop model is also presented. An enhanced controller based on these models is designed and the performance improvements discussed. (author) 5 figs., 9 refs
Miller, R.J.; Najaf-Zadeh, K.; Darlington, H.T.; McNair, H.D.; Seidenstein, S.; Williams, A.R.
1982-10-01
Human factors is a systems-oriented interdisciplinary specialty concerned with the design of systems, equipment, facilities and the operational environment. An important aspect leading to the design requirements is the determination of the information requirements for electric power dispatch control centers. There are significant differences between the system operator's actions during normal and degraded states of power system operation, and power system restoration. This project evaluated the information the operator requires for normal power system and control system operations and investigates the changes of information required by the operator as the power system and/or the control system degrades from a normal operating state. The Phase II study, published in two volumes, defines power system states and control system conditions to which operator information content can be related. This volume presents detailed data concerning operator information needs that identify the needs for and the uses of power system information by a system operator in conditions ranging from normal through degraded operation. The study defines power system states and control system conditions to which operator information content can be related, and it identifies the requisite information as consistent with current industry practice so as to aid control system designers. Training requirements are also included for planning entry-level and follow-on training for operators.
Are tidal volume measurements in neonatal pressure-controlled ventilation accurate?
Chow, Lily C; Vanderhal, Andre; Raber, Jorge; Sola, Augusto
2002-09-01
Bedside pulmonary mechanics monitors (PMM) have become useful in ventilatory management in neonates. These monitors are used more frequently due to recent improvements in data-processing capabilities. PMM devices are often part of the ventilator or are separate units. The accuracy and reliability of these systems have not been carefully evaluated. We compared a single ventilatory parameter, tidal volume (V(t)), as measured by several systems. We looked at two freestanding PMMs: the Ventrak Respiratory Monitoring System (Novametrix, Wallingford, CT) and the Bicore CP-100 Neonatal Pulmonary Monitor (Allied Health Care Products, Riverside, CA), and three ventilators with built-in PMM: the VIP Bird Ventilator (Bird Products Corp., Palm Springs, CA), Siemens Servo 300A (Siemens-Elema AB, Solna, Sweden), and Drager Babylog 8000 (Drager, Inc., Chantilly, VA). A calibrated syringe (Hans Rudolph, Inc., Kansas City, MO) was used to deliver tidal volumes of 4, 10, and 20 mL to each ventilator system coupled with a freestanding PMM. After achieving steady state, six consecutive V(t) readings were taken simultaneously from the freestanding PMM and each ventilator. In a second portion of the bench study, we used pressure-control ventilation and measured exhaled tidal volume (V(te)) while ventilating a Bear Test Lung with the same three ventilators. We adjusted peak inspiratory pressure (PIP) under controlled conditions to achieve the three different targeted tidal volumes on the paired freestanding PMM. Again, six V(te) measurements were recorded for each tidal volume. Means and standard deviations were calculated.The percentage difference in measurement of V(t) delivered by calibrated syringe varied greatly, with the greatest discrepancy seen in the smallest tidal volumes, by up to 28%. In pressure control mode, V(te) as measured by the Siemens was significantly overestimated by 20-95%, with the biggest discrepancy at the smallest V(te), particularly when paired with the Bicore
Scramjet Isolator Modeling and Control
2011-12-01
Layer Interactions,” (NATO) AGARD CP 193, May 1976. 17. Cox, C., Lewis, C., Pap, R., Glover, C., Priddy, K., Edwards, J., and McCarty, D., “Prediction...Static Polynomial Model . . . . . . . . . . . . . . . . . . 73 5.2 Continuous Linear Model with Static Polynomial Input . 75 5.3 ARX Models with Static...Vector of NARX model regression values . . . . . . . . . . 70 Nr Number of samples for a run . . . . . . . . . . . . . . . . 73 ΘNL Vector of
Stimulation model for lenticular sands: Volume 2, Users manual
Rybicki, E.F.; Luiskutty, C.T.; Sutrick, J.S.; Palmer, I.D.; Shah, G.H.; Tomutsa, L.
1987-07-01
This User's Manual contains information for four fracture/proppant models. TUPROP1 contains a Geertsma and de Klerk type fracture model. The section of the program utilizing the proppant fracture geometry data from the pseudo three-dimensional highly elongated fracture model is called TUPROPC. The analogous proppant section of the program that was modified to accept fracture shape data from SA3DFRAC is called TUPROPS. TUPROPS also includes fracture closure. Finally there is the penny fracture and its proppant model, PENNPROP. In the first three chapters, the proppant sections are based on the same theory for determining the proppant distribution but have modifications to support variable height fractures and modifications to accept fracture geometry from three different fracture models. Thus, information about each proppant model in the User's Manual builds on information supplied in the previous chapter. The exception to the development of combined treatment models is the penny fracture and its proppant model. In this case, a completely new proppant model was developed. A description of how to use the combined treatment model for the penny fracture is contained in Chapter 4. 2 refs.
Blood volume, blood pressure and total body sodium: internal signalling and output control
Bie, P
2009-01-01
Total body sodium and arterial blood pressure (ABP) are mutually dependent variables regulated by complex control systems. This review addresses the role of ABP in the normal control of sodium excretion (NaEx), and the physiological control of renin secretion. NaEx is a pivotal determinant of ABP......, and under experimental conditions, ABP is a powerful, independent controller of NaEx. Blood volume is a function of dietary salt intake; however, ABP is not, at least not in steady states. A transient increase in ABP after a step-up in sodium intake could provide a causal relationship between ABP...... and the regulation of NaEx via a hypothetical integrative control system. However, recent data show that subtle sodium loading (simulating salty meals) causes robust natriuresis without changes in ABP. Changes in ABP are not necessary for natriuresis. Normal sodium excretion is not regulated by pressure. Plasma...
System Identification, Environmental Modelling, and Control System Design
Garnier, Hugues
2012-01-01
System Identification, Environmetric Modelling, and Control Systems Design is dedicated to Professor Peter Young on the occasion of his seventieth birthday. Professor Young has been a pioneer in systems and control, and over the past 45 years he has influenced many developments in this field. This volume is comprised of a collection of contributions by leading experts in system identification, time-series analysis, environmetric modelling and control system design – modern research in topics that reflect important areas of interest in Professor Young’s research career. Recent theoretical developments in and relevant applications of these areas are explored treating the various subjects broadly and in depth. The authoritative and up-to-date research presented here will be of interest to academic researcher in control and disciplines related to environmental research, particularly those to with water systems. The tutorial style in which many of the contributions are composed also makes the book suitable as ...
Modeling and identification for robot motion control
Kostic, D.; Jager, de A.G.; Steinbuch, M.; Kurfess, T.R.
2004-01-01
This chapter deals with the problems of robot modelling and identification for high-performance model-based motion control. A derivation of robot kinematic and dynamic models was explained. Modelling of friction effects was also discussed. Use of a writing task to establish correctness of the models
Optimal models of extreme volume-prices are time-dependent
Rocha, Paulo; Boto, João Pedro; Raischel, Frank; Lind, Pedro G
2015-01-01
We present evidence that the best model for empirical volume-price distributions is not always the same and it strongly depends in (i) the region of the volume-price spectrum that one wants to model and (ii) the period in time that is being modelled. To show these two features we analyze stocks of the New York stock market with four different models: Γ, Γ-inverse, log-normal, and Weibull distributions. To evaluate the accuracy of each model we use standard relative deviations as well as the Kullback-Leibler distance and introduce an additional distance particularly suited to evaluate how accurate are the models for the distribution tails (large volume-price). Finally we put our findings in perspective and discuss how they can be extended to other situations in finance engineering
Mesorad dose assessment model. Volume 1. Technical basis
Scherpelz, R.I.; Bander, T.J.; Athey, G.F.; Ramsdell, J.V.
1986-03-01
MESORAD is a dose assessment model for emergency response applications. Using release data for as many as 50 radionuclides, the model calculates: (1) external doses resulting from exposure to radiation emitted by radionuclides contained in elevated or deposited material; (2) internal dose commitment resulting from inhalation; and (3) total whole-body doses. External doses from airborne material are calculated using semi-infinite and finite cloud approximations. At each stage in model execution, the appropriate approximation is selected after considering the cloud dimensions. Atmospheric processes are represented in MESORAD by a combination of Lagrangian puff and Gaussian plume dispersion models, a source depletion (deposition velocity) dry deposition model, and a wet deposition model using washout coefficients based on precipitation rates
PREDICTION OF THE MIXING ENTHALPIES OF BINARY LIQUID ALLOYS BY MOLECULAR INTERACTION VOLUME MODEL
H.W.Yang; D.P.Tao; Z.H.Zhou
2008-01-01
The mixing enthalpies of 23 binary liquid alloys are calculated by molecular interaction volume model (MIVM), which is a two-parameter model with the partial molar infinite dilute mixing enthalpies. The predicted values are in agreement with the experimental data and then indicate that the model is reliable and convenient.
Renteria Marquez, I A; Bolborici, V
2017-05-01
This manuscript presents a method to model in detail the piezoelectric traveling wave rotary ultrasonic motor (PTRUSM) stator response under the action of DC and AC voltages. The stator is modeled with a discrete two dimensional system of equations using the finite volume method (FVM). In order to obtain accurate results, a model of the stator bridge is included into the stator model. The model of the stator under the action of DC voltage is presented first, and the results of the model are compared versus a similar model using the commercial finite element software COMSOL Multiphysics. One can observe that there is a difference of less than 5% between the displacements of the stator using the proposed model and the one with COMSOL Multiphysics. After that, the model of the stator under the action of AC voltages is presented. The time domain analysis shows the generation of the traveling wave in the stator surface. One can use this model to accurately calculate the stator surface velocities, elliptical motion of the stator surface and the amplitude and shape of the stator traveling wave. A system of equations discretized with the finite volume method can easily be transformed into electrical circuits, because of that, FVM may be a better choice to develop a model-based control strategy for the PTRUSM. Copyright © 2017 Elsevier B.V. All rights reserved.
A model for vented deflagration of hydrogen in a volume
Mulpuru, S.R.; Wilkin, G.B.
1982-02-01
A simple model was constructed to predict the property transients resulting from the deflagration of a combustible mixture in a sphere or cylinder with venting of the gas mixture to the environment. A computer program VENT, was written to solve the model equation. The model will be particularly useful for studying hydrogen burning effects in loss-of-coolant plus losss of emergency coolant accidents in CANDU reactors
Modelling and control of systems with flow
van Mourik, S.
2008-01-01
In practice, feedback control design consists of three steps: modelling, model reduction and controller design for the reduced model. Systems with flow are often complicated, and there is yet no standard algorithm that integrates these steps. In this thesis we make a modest effort by considering two
Nonlinear control of the Salnikov model reaction
Recke, Bodil; Jørgensen, Sten Bay
1999-01-01
This paper explores different nonlinear control schemes, applied to a simple model reaction. The model is the Salnikov model, consisting of two ordinary differential equations. The control strategies investigated are I/O-linearisation, Exact linearisation, exact linearisation combined with LQR...
1988-07-29
manually under controller comiand. 40.3.7.1.2.1.1.2-19 b. Ordering - In manual ordering , the 780 controller shall have the capability to put o new FOE...7.1.2.1.1.2-09 a. Posting - This orgonization of FOEs shall 780 be provided at the option of the controller. 40.3.7.1.2.1.1.2-19 b. Ordering - In manual ... ordering , the 780 controller shall have the capability to put o new FOE in the appropriate place in a list and to move FOEs with respect to one another
Castillo, Carlos; Pérez, Rafael
2017-04-01
The assessment of gully erosion volumes is essential for the quantification of soil losses derived from this relevant degradation process. Traditionally, 2D and 3D approaches has been applied for this purpose (Casalí et al., 2006). Although innovative 3D approaches have recently been proposed for gully volume quantification, a renewed interest can be found in literature regarding the useful information that cross-section analysis still provides in gully erosion research. Moreover, the application of methods based on 2D approaches can be the most cost-effective approach in many situations such as preliminary studies with low accuracy requirements or surveys under time or budget constraints. The main aim of this work is to examine the key factors controlling volume error variability in 2D gully assessment by means of a stochastic experiment involving a Monte Carlo analysis over synthetic gully profiles in order to 1) contribute to a better understanding of the drivers and magnitude of gully erosion 2D-surveys uncertainty and 2) provide guidelines for optimal survey designs. Owing to the stochastic properties of error generation in 2D volume assessment, a statistical approach was followed to generate a large and significant set of gully reach configurations to evaluate quantitatively the influence of the main factors controlling the uncertainty of the volume assessment. For this purpose, a simulation algorithm in Matlab® code was written, involving the following stages: - Generation of synthetic gully area profiles with different degrees of complexity (characterized by the cross-section variability) - Simulation of field measurements characterised by a survey intensity and the precision of the measurement method - Quantification of the volume error uncertainty as a function of the key factors In this communication we will present the relationships between volume error and the studied factors and propose guidelines for 2D field surveys based on the minimal survey
Open loop control of filament heating power supply for large volume plasma device
Sugandhi, R., E-mail: ritesh@ipr.res.in [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Srivastava, P.K.; Sanyasi, A.K. [Homi Bhabha National Institute, Mumbai 400094 (India); Srivastav, Prabhakar [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Awasthi, L.M., E-mail: kushagra.lalit@gmail.com [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Mattoo, S.K. [Homi Bhabha National Institute, Mumbai 400094 (India)
2017-02-15
A power supply (20 V, 10 kA) for powering the filamentary cathode has been procured, interfaced and integrated with the centralized control system of Large Volume Plasma Device (LVPD). Software interface has been developed on the standard Modbus RTU communication protocol. It facilitates the dashboard for configuration, on line status monitoring, alarm management, data acquisition, synchronization and controls. It has been tested for stable operation of the power supply for the operational capabilities. The paper highlights the motivation, interface description, implementation and results obtained.
Open loop control of filament heating power supply for large volume plasma device
Sugandhi, R.; Srivastava, P.K.; Sanyasi, A.K.; Srivastav, Prabhakar; Awasthi, L.M.; Mattoo, S.K.
2017-01-01
A power supply (20 V, 10 kA) for powering the filamentary cathode has been procured, interfaced and integrated with the centralized control system of Large Volume Plasma Device (LVPD). Software interface has been developed on the standard Modbus RTU communication protocol. It facilitates the dashboard for configuration, on line status monitoring, alarm management, data acquisition, synchronization and controls. It has been tested for stable operation of the power supply for the operational capabilities. The paper highlights the motivation, interface description, implementation and results obtained.
A prototype of volume-controlled tidal liquid ventilator using independent piston pumps.
Robert, Raymond; Micheau, Philippe; Cyr, Stéphane; Lesur, Olivier; Praud, Jean-Paul; Walti, Hervé
2006-01-01
Liquid ventilation using perfluorochemicals (PFC) offers clear theoretical advantages over gas ventilation, such as decreased lung damage, recruitment of collapsed lung regions, and lavage of inflammatory debris. We present a total liquid ventilator designed to ventilate patients with completely filled lungs with a tidal volume of PFC liquid. The two independent piston pumps are volume controlled and pressure limited. Measurable pumping errors are corrected by a programmed supervisor module, which modifies the inserted or withdrawn volume. Pump independence also allows easy functional residual capacity modifications during ventilation. The bubble gas exchanger is divided into two sections such that the PFC exiting the lungs is not in contact with the PFC entering the lungs. The heating system is incorporated into the metallic base of the gas exchanger, and a heat-sink-type condenser is placed on top of the exchanger to retrieve PFC vapors. The prototype was tested on 5 healthy term newborn lambs (<5 days old). The results demonstrate the efficiency and safety of the prototype in maintaining adequate gas exchange, normal acido-basis equilibrium, and cardiovascular stability during a short, 2-hour total liquid ventilator. Airway pressure, lung volume, and ventilation scheme were maintained in the targeted range.
Yu, Alex; Jackson, Trachette; Tsume, Yasuhiro; Koenigsknecht, Mark; Wysocki, Jeffrey; Marciani, Luca; Amidon, Gordon L; Frances, Ann; Baker, Jason R; Hasler, William; Wen, Bo; Pai, Amit; Sun, Duxin
2017-11-01
Gastrointestinal (GI) fluid volume and its dynamic change are integral to study drug disintegration, dissolution, transit, and absorption. However, key questions regarding the local volume and its absorption, secretion, and transit remain unanswered. The dynamic fluid compartment absorption and transit (DFCAT) model is proposed to estimate in vivo GI volume and GI fluid transport based on magnetic resonance imaging (MRI) quantified fluid volume. The model was validated using GI local concentration of phenol red in human GI tract, which was directly measured by human GI intubation study after oral dosing of non-absorbable phenol red. The measured local GI concentration of phenol red ranged from 0.05 to 168 μg/mL (stomach), to 563 μg/mL (duodenum), to 202 μg/mL (proximal jejunum), and to 478 μg/mL (distal jejunum). The DFCAT model characterized observed MRI fluid volume and its dynamic changes from 275 to 46.5 mL in stomach (from 0 to 30 min) with mucus layer volume of 40 mL. The volumes of the 30 small intestine compartments were characterized by a max of 14.98 mL to a min of 0.26 mL (0-120 min) and a mucus layer volume of 5 mL per compartment. Regional fluid volumes over 0 to 120 min ranged from 5.6 to 20.38 mL in the proximal small intestine, 36.4 to 44.08 mL in distal small intestine, and from 42 to 64.46 mL in total small intestine. The DFCAT model can be applied to predict drug dissolution and absorption in the human GI tract with future improvements.
Modeling Control Situations in Power System Operations
Saleem, Arshad; Lind, Morten; Singh, Sri Niwas
2010-01-01
for intelligent operation and control must represent system features, so that information from measurements can be related to possible system states and to control actions. These general modeling requirements are well understood, but it is, in general, difficult to translate them into a model because of the lack...... of explicit principles for model construction. This paper presents a work on using explicit means-ends model based reasoning about complex control situations which results in maintaining consistent perspectives and selecting appropriate control action for goal driven agents. An example of power system......Increased interconnection and loading of the power system along with deregulation has brought new challenges for electric power system operation, control and automation. Traditional power system models used in intelligent operation and control are highly dependent on the task purpose. Thus, a model...
Modeling and control of greenhouse crop growth
Rodríguez, Francisco; Guzmán, José Luis; Ramírez-Arias, Armando
2015-01-01
A discussion of challenges related to the modeling and control of greenhouse crop growth, this book presents state-of-the-art answers to those challenges. The authors model the subsystems involved in successful greenhouse control using different techniques and show how the models obtained can be exploited for simulation or control design; they suggest ideas for the development of physical and/or black-box models for this purpose. Strategies for the control of climate- and irrigation-related variables are brought forward. The uses of PID control and feedforward compensators, both widely used in commercial tools, are summarized. The benefits of advanced control techniques—event-based, robust, and predictive control, for example—are used to improve on the performance of those basic methods. A hierarchical control architecture is developed governed by a high-level multiobjective optimization approach rather than traditional constrained optimization and artificial intelligence techniques. Reference trajector...
McLoughlin, R.F.; Ryan, M.V.; Heuston, P.M.; McCoy, C.T.; Masterson, J.B.
1992-01-01
The purpose of this study was to construct and evaluate a statistical model for the quantitative analysis of computed tomographic brain images. Data were derived from standard sections in 34 normal studies. A model representing the intercranial pure tissue and partial volume areas, with allowance for beam hardening, was developed. The average percentage error in estimation of areas, derived from phantom tests using the model, was 28.47%. We conclude that our model is not sufficiently accurate to be of clinical use, even though allowance was made for partial volume and beam hardening effects. (author)
Applying model predictive control to power system frequency control
Ersdal, AM; Imsland, L; Cecilio, IM; Fabozzi, D; Thornhill, NF
2013-01-01
16.07.14 KB Ok to add accepted version to Spiral Model predictive control (MPC) is investigated as a control method which may offer advantages in frequency control of power systems than the control methods applied today, especially in presence of increased renewable energy penetration. The MPC includes constraints on both generation amount and generation rate of change, and it is tested on a one-area system. The proposed MPC is tested against a conventional proportional-integral (PI) cont...
A hybrid ARIMA and neural network model applied to forecast catch volumes of Selar crumenophthalmus
Aquino, Ronald L.; Alcantara, Nialle Loui Mar T.; Addawe, Rizavel C.
2017-11-01
The Selar crumenophthalmus with the English name big-eyed scad fish, locally known as matang-baka, is one of the fishes commonly caught along the waters of La Union, Philippines. The study deals with the forecasting of catch volumes of big-eyed scad fish for commercial consumption. The data used are quarterly caught volumes of big-eyed scad fish from 2002 to first quarter of 2017. This actual data is available from the open stat database published by the Philippine Statistics Authority (PSA)whose task is to collect, compiles, analyzes and publish information concerning different aspects of the Philippine setting. Autoregressive Integrated Moving Average (ARIMA) models, Artificial Neural Network (ANN) model and the Hybrid model consisting of ARIMA and ANN were developed to forecast catch volumes of big-eyed scad fish. Statistical errors such as Mean Absolute Errors (MAE) and Root Mean Square Errors (RMSE) were computed and compared to choose the most suitable model for forecasting the catch volume for the next few quarters. A comparison of the results of each model and corresponding statistical errors reveals that the hybrid model, ARIMA-ANN (2,1,2)(6:3:1), is the most suitable model to forecast the catch volumes of the big-eyed scad fish for the next few quarters.
Fractional Order Models of Industrial Pneumatic Controllers
Abolhassan Razminia
2014-01-01
Full Text Available This paper addresses a new approach for modeling of versatile controllers in industrial automation and process control systems such as pneumatic controllers. Some fractional order dynamical models are developed for pressure and pneumatic systems with bellows-nozzle-flapper configuration. In the light of fractional calculus, a fractional order derivative-derivative (FrDD controller and integral-derivative (FrID are remodeled. Numerical simulations illustrate the application of the obtained theoretical results in simple examples.
Modeling surface area to volume effects on borosilicate glass dissolution
Bourcier, W.L.; Ebert, W.L.; Feng, X.
1992-11-01
We simulated the reaction of SRL-131 glass with equilibrated J-13 water in order to investigate the effects of surface area to volume ratio (SA/V) on glass dissolution. We show that glass-fluid ion exchange causes solution pH to rise to progressively higher values as SA/V increases. Because the ion exchange is rapid relative to the duration of the glass dissolution experiment, the pH effect does not scale with (SA/V)*time. Experiments compared at the same (SA/V)*time value therefore have different pHs, with higher pHs at higher SA/V ratios. Both experimental data and our simulation results show similar trends of increasing reaction rate as a function of SA/V ratio when scaled to (SA/V)*time. Glasses which react in systems of differing SA/V ratio therefore follow different reaction paths and high SA/V ratios cannot be used to generate data which accurately scales to long time periods unless the ion exchange effect is taken into account. We suggest some simple test designs which enable more reliable high. SA/V accelerated tests
Measurement and modeling of advanced coal conversion processes, Volume III
Ghani, M.U.; Hobbs, M.L.; Hamblen, D.G. [and others
1993-08-01
A generalized one-dimensional, heterogeneous, steady-state, fixed-bed model for coal gasification and combustion is presented. The model, FBED-1, is a design and analysis tool that can be used to simulate a variety of gasification, devolatilization, and combustion processes. The model considers separate gas and solid temperatures, axially variable solid and gas flow rates, variable bed void fraction, coal drying, devolatilization based on chemical functional group composition, depolymerization, vaporization and crosslinking, oxidation, and gasification of char, and partial equilibrium in the gas phase.
Measurement and modeling of advanced coal conversion processes, Volume II
Solomon, P.R.; Serio, M.A.; Hamblen, D.G. [and others
1993-06-01
A two dimensional, steady-state model for describing a variety of reactive and nonreactive flows, including pulverized coal combustion and gasification, is presented. The model, referred to as 93-PCGC-2 is applicable to cylindrical, axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using a discrete ordinates method. The particle phase is modeled in a lagrangian framework, such that mean paths of particle groups are followed. A new coal-general devolatilization submodel (FG-DVC) with coal swelling and char reactivity submodels has been added.
Volume and aboveground biomass models for dry Miombo woodland in Tanzania
Mwakalukwa, Ezekiel Edward; Meilby, Henrik; Treue, Thorsten
2014-01-01
Tools to accurately estimate tree volume and biomass are scarce for most forest types in East Africa, including Tanzania. Based on a sample of 142 trees and 57 shrubs from a 6,065 ha area of dry miombo woodland in Iringa rural district in Tanzania, regression models were developed for volume...... and biomass of three important species, Brachystegia spiciformis Benth. (n=40), Combretum molle G. Don (n=41), and Dalbergia arbutifolia Baker (n=37) separately, and for broader samples of trees (28 species, n=72), shrubs (16 species, n=31), and trees and shrubs combined (44 species, n=104). Applied...... of the predictions tended to increase from general to species-specific models. Except for a few volume and biomass models developed for shrubs, all models had R2 values of 96–99%. Thus, the models appear robust and should be applicable to forests with similar site conditions, species, and diameter ranges....
Plant control using embedded predictive models
Godbole, S.S.; Gabler, W.E.; Eschbach, S.L.
1990-01-01
B and W recently undertook the design of an advanced light water reactor control system. A concept new to nuclear steam system (NSS) control was developed. The concept, which is called the Predictor-Corrector, uses mathematical models of portions of the controlled NSS to calculate, at various levels within the system, demand and control element position signals necessary to satisfy electrical demand. The models give the control system the ability to reduce overcooling and undercooling of the reactor coolant system during transients and upsets. Two types of mathematical models were developed for use in designing and testing the control system. One model was a conventional, comprehensive NSS model that responds to control system outputs and calculates the resultant changes in plant variables that are then used as inputs to the control system. Two other models, embedded in the control system, were less conventional, inverse models. These models accept as inputs plant variables, equipment states, and demand signals and predict plant operating conditions and control element states that will satisfy the demands. This paper reports preliminary results of closed-loop Reactor Coolant (RC) pump trip and normal load reduction testing of the advanced concept. Results of additional transient testing, and of open and closed loop stability analyses will be reported as they are available
Predictive Software Cost Model Study. Volume I. Final Technical Report.
1980-06-01
development phase to identify computer resources necessary to support computer programs after transfer of program manangement responsibility and system... classical model development with refinements specifically applicable to avionics systems. The refinements are the result of the Phase I literature search
LOGAM (Logistic Analysis Model). Volume 2. Users Manual.
1982-08-01
as opposed to simulation models which represent a system’s behavior as a function of time. These latter classes of models are often complex. They...includes the cost of ammunition and missiles comsumed by the system being costed during unit training. Excluded is the cost of ammunition consumed during...data. The results obtained from sensitivity testing may be used to construct graphs which display the behavior of the maintenance concept over the range
Prediction of resource volumes at untested locations using simple local prediction models
Attanasi, E.D.; Coburn, T.C.; Freeman, P.A.
2006-01-01
This paper shows how local spatial nonparametric prediction models can be applied to estimate volumes of recoverable gas resources at individual undrilled sites, at multiple sites on a regional scale, and to compute confidence bounds for regional volumes based on the distribution of those estimates. An approach that combines cross-validation, the jackknife, and bootstrap procedures is used to accomplish this task. Simulation experiments show that cross-validation can be applied beneficially to select an appropriate prediction model. The cross-validation procedure worked well for a wide range of different states of nature and levels of information. Jackknife procedures are used to compute individual prediction estimation errors at undrilled locations. The jackknife replicates also are used with a bootstrap resampling procedure to compute confidence bounds for the total volume. The method was applied to data (partitioned into a training set and target set) from the Devonian Antrim Shale continuous-type gas play in the Michigan Basin in Otsego County, Michigan. The analysis showed that the model estimate of total recoverable volumes at prediction sites is within 4 percent of the total observed volume. The model predictions also provide frequency distributions of the cell volumes at the production unit scale. Such distributions are the basis for subsequent economic analyses. ?? Springer Science+Business Media, LLC 2007.
A physical multifield model predicts the development of volume and structure in the human brain
Rooij, Rijk de; Kuhl, Ellen
2018-03-01
The prenatal development of the human brain is characterized by a rapid increase in brain volume and a development of a highly folded cortex. At the cellular level, these events are enabled by symmetric and asymmetric cell division in the ventricular regions of the brain followed by an outwards cell migration towards the peripheral regions. The role of mechanics during brain development has been suggested and acknowledged in past decades, but remains insufficiently understood. Here we propose a mechanistic model that couples cell division, cell migration, and brain volume growth to accurately model the developing brain between weeks 10 and 29 of gestation. Our model accurately predicts a 160-fold volume increase from 1.5 cm3 at week 10 to 235 cm3 at week 29 of gestation. In agreement with human brain development, the cortex begins to form around week 22 and accounts for about 30% of the total brain volume at week 29. Our results show that cell division and coupling between cell density and volume growth are essential to accurately model brain volume development, whereas cell migration and diffusion contribute mainly to the development of the cortex. We demonstrate that complex folding patterns, including sinusoidal folds and creases, emerge naturally as the cortex develops, even for low stiffness contrasts between the cortex and subcortex.
Towards an adaptive model for greenhouse control
Speetjens, S.L.; Stigter, J.D.; Straten, van G.
2009-01-01
Application of advanced controllers in horticultural practice requires detailed models. Even highly sophisticated models require regular attention from the user due to changing circumstances like plant growth, changing material properties and modifications in greenhouse design and layout. Moreover,
Hayhurst, Kelly J. (Editor)
2008-01-01
The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes configuration management and quality assurance documents from the GCS project. Volume 4 contains six appendices: A. Software Accomplishment Summary for the Guidance and Control Software Project; B. Software Configuration Index for the Guidance and Control Software Project; C. Configuration Management Records for the Guidance and Control Software Project; D. Software Quality Assurance Records for the Guidance and Control Software Project; E. Problem Report for the Pluto Implementation of the Guidance and Control Software Project; and F. Support Documentation Change Reports for the Guidance and Control Software Project.
Arschang eValipour
2012-10-01
Full Text Available Rationale: In clinical trials, homogeneous emphysema patients have responded well to upper lobe volume reduction but not lower lobe volume reduction. Materials/Methods: To understand the physiological basis for this observation, a computer model was developed to simulate the effects of upper and lower lobe lung volume reduction on RV/TLC and lung recoil in homogeneous emphysema.Results: Patients with homogeneous emphysema received either upper or lower lobe volume reduction therapy based on findings of radionucleotide scintigraphy scanning. CT analysis of lobar volumes showed that patients undergoing upper (n=18; -265 mL/site and lower lobe treatment (n=11; -217 mL/site experienced similar reductions in lung volume. However, only upper lobe treatment improved FEV1 (+11.1±14.7% vs -4.4±15.8% and RV/TLC (-5.4± 8.1% vs -2.4±8.6%. Model simulations provided an unexpected explanation for this response. Increases in transpulmonary pressure subsequent to volume reduction increased RV/TLC in upper lobe alveoli, while caudal shifts in airway closure decreased RV/TLC in lower lobe alveoli. Upper lobe treatment, which eliminates apical alveoli with high RV/TLC values, lowers the average RV/TLC of the lung. Conversely, lower lobe treatment, which eliminates caudal alveoli with low RV/TLC values, has less effect. Conclusions: Lower lobe treatment in homogeneous emphysema is uniformly less effective than upper lobe treatment.
Determination of bone mineral volume fraction using impedance analysis and Bruggeman model
Ciuchi, Ioana Veronica; Olariu, Cristina Stefania, E-mail: oocristina@yahoo.com; Mitoseriu, Liliana, E-mail: lmtsr@uaic.ro
2013-11-20
Highlights: • Mineral volume fraction of a bone sample was determined. • Dielectric properties for bone sample and for the collagen type I were determined by impedance spectroscopy. • Bruggeman effective medium approximation was applied in order to evaluate mineral volume fraction of the sample. • The computed values were compared with ones derived from a histogram test performed on SEM micrographs. -- Abstract: Measurements by impedance spectroscopy and Bruggeman effective medium approximation model were employed in order to determine the mineral volume fraction of dry bone. This approach assumes that two or more phases are present into the composite: the matrix (environment) and the other ones are inclusion phases. A fragment of femur diaphysis dense bone from a young pig was investigated in its dehydrated state. Measuring the dielectric properties of bone and its main components (hydroxyapatite and collagen) and using the Bruggeman approach, the mineral volume filling factor was determined. The computed volume fraction of the mineral volume fraction was confirmed by a histogram test analysis based on the SEM microstructures. In spite of its simplicity, the method provides a good approximation for the bone mineral volume fraction. The method which uses impedance spectroscopy and EMA modeling can be further developed by considering the conductive components of the bone tissue as a non-invasive in situ impedance technique for bone composition evaluation and monitoring.
Determination of bone mineral volume fraction using impedance analysis and Bruggeman model
Ciuchi, Ioana Veronica; Olariu, Cristina Stefania; Mitoseriu, Liliana
2013-01-01
Highlights: • Mineral volume fraction of a bone sample was determined. • Dielectric properties for bone sample and for the collagen type I were determined by impedance spectroscopy. • Bruggeman effective medium approximation was applied in order to evaluate mineral volume fraction of the sample. • The computed values were compared with ones derived from a histogram test performed on SEM micrographs. -- Abstract: Measurements by impedance spectroscopy and Bruggeman effective medium approximation model were employed in order to determine the mineral volume fraction of dry bone. This approach assumes that two or more phases are present into the composite: the matrix (environment) and the other ones are inclusion phases. A fragment of femur diaphysis dense bone from a young pig was investigated in its dehydrated state. Measuring the dielectric properties of bone and its main components (hydroxyapatite and collagen) and using the Bruggeman approach, the mineral volume filling factor was determined. The computed volume fraction of the mineral volume fraction was confirmed by a histogram test analysis based on the SEM microstructures. In spite of its simplicity, the method provides a good approximation for the bone mineral volume fraction. The method which uses impedance spectroscopy and EMA modeling can be further developed by considering the conductive components of the bone tissue as a non-invasive in situ impedance technique for bone composition evaluation and monitoring
Developing a stochastic traffic volume prediction model for public-private partnership projects
Phong, Nguyen Thanh; Likhitruangsilp, Veerasak; Onishi, Masamitsu
2017-11-01
Transportation projects require an enormous amount of capital investment resulting from their tremendous size, complexity, and risk. Due to the limitation of public finances, the private sector is invited to participate in transportation project development. The private sector can entirely or partially invest in transportation projects in the form of Public-Private Partnership (PPP) scheme, which has been an attractive option for several developing countries, including Vietnam. There are many factors affecting the success of PPP projects. The accurate prediction of traffic volume is considered one of the key success factors of PPP transportation projects. However, only few research works investigated how to predict traffic volume over a long period of time. Moreover, conventional traffic volume forecasting methods are usually based on deterministic models which predict a single value of traffic volume but do not consider risk and uncertainty. This knowledge gap makes it difficult for concessionaires to estimate PPP transportation project revenues accurately. The objective of this paper is to develop a probabilistic traffic volume prediction model. First, traffic volumes were estimated following the Geometric Brownian Motion (GBM) process. Monte Carlo technique is then applied to simulate different scenarios. The results show that this stochastic approach can systematically analyze variations in the traffic volume and yield more reliable estimates for PPP projects.
Kewisch, J.; Mane, V.; Clifford, T.; Hartmann, H.; Kahn, T.; Oerter, B.; Peggs, S.
1994-01-01
This paper introduces the hardware and software concepts for the implementation of the ramp controls. The hardware part of the ramp controls consists of a number of multi-purpose Wave Form Generators (WFGS) which control the settings of accelerator hardware directly or indirectly by controlling their WFG. A Real Time Data Link (RTDL) data transfer system connects the WFGs in a three layer architecture. To the usual two layers which generate an independent timing signal and dependent set points, respectively, an intermediate layer is added which produces accelerator parameters such as the magnet strength. The task of the bottom layer is therefore reduced to the function of implementing those parameters. This architecture de-couples two independent functions which axe normally folded together. The function of the hardware becomes modular and easily maintainable. The ramp control software is layered in the same way. Between the top layer (the ramp procedure application program) and the bottom layer (the hardware interface) an additional layer of ''manager'' programs allow operation of accelerator subsystems
Modeling and Modern Control of Wind Power
This book covers the modeling of wind power and application of modern control methods to the wind power control—specifically the models of type 3 and type 4 wind turbines. The modeling aspects will help readers to streamline the wind turbine and wind power plant modeling, and reduce the burden...... of power system simulations to investigate the impact of wind power on power systems. The use of modern control methods will help technology development, especially from the perspective of manufactures....
Xu, Yongbin; Xie, Haihong; Wu, Liuyi
2018-05-01
The share of coal transportation in the total railway freight volume is about 50%. As is widely acknowledged, coal industry is vulnerable to the economic situation and national policies. Coal transportation volume fluctuates significantly under the new economic normal. Grasp the overall development trend of railway coal transportation market, have important reference and guidance significance to the railway and coal industry decision-making. By analyzing the economic indicators and policy implications, this paper expounds the trend of the coal transportation volume, and further combines the economic indicators with the high correlation with the coal transportation volume with the traditional traffic prediction model to establish a combined forecasting model based on the back propagation neural network. The error of the prediction results is tested, which proves that the method has higher accuracy and has practical application.
Modeling, Control and Coordination of Helicopter Systems
Ren, Beibei; Chen, Chang; Fua, Cheng-Heng; Lee, Tong Heng
2012-01-01
Modeling, Control and Coordination of Helicopter Systems provides a comprehensive treatment of helicopter systems, ranging from related nonlinear flight dynamic modeling and stability analysis to advanced control design for single helicopter systems, and also covers issues related to the coordination and formation control of multiple helicopter systems to achieve high performance tasks. Ensuring stability in helicopter flight is a challenging problem for nonlinear control design and development. This book is a valuable reference on modeling, control and coordination of helicopter systems,providing readers with practical solutions for the problems that still plague helicopter system design and implementation. Readers will gain a complete picture of helicopters at the systems level, as well as a better understanding of the technical intricacies involved. This book also: Presents a complete picture of modeling, control and coordination for helicopter systems Provides a modeling platform for a general class of ro...
Probabilistic Modeling of Aircraft Trajectories for Dynamic Separation Volumes
Lewis, Timothy A.
2016-01-01
With a proliferation of new and unconventional vehicles and operations expected in the future, the ab initio airspace design will require new approaches to trajectory prediction for separation assurance and other air traffic management functions. This paper presents an approach to probabilistic modeling of the trajectory of an aircraft when its intent is unknown. The approach uses a set of feature functions to constrain a maximum entropy probability distribution based on a set of observed aircraft trajectories. This model can be used to sample new aircraft trajectories to form an ensemble reflecting the variability in an aircraft's intent. The model learning process ensures that the variability in this ensemble reflects the behavior observed in the original data set. Computational examples are presented.
Intrinsic controls on the range of volumes, morphologies, and dimensions of submarine lobes
Prélat, A.; Covault, J. A.; Hodgson, D. M.; Fildani, A.; Flint, S. S.
2010-12-01
Submarine lobe dimensions from six different systems are compared: 1) the exhumed Permian Fan 3 lobe complex of the Tanqua Karoo, South Africa; 2) the modern Amazon fan channel-mouth lobe complex, offshore Brazil; 3) a portion of the modern distal Zaïre fan, offshore Angola/Congo; 4) a Pleistocene fan of the Kutai basin, subsurface offshore Indonesia; 5) the modern Golo system, offshore east Corsica, France; and 6) a shallow subsurface lobe complex , offshore Nigeria. These six systems have significantly different source-to-sink configurations (shelf dimension and slope topography), sediment supply characteristics (available grain size range and supply rate), tectonic settings, (palaeo) latitude, and delivery systems. Despite these differences, lobe deposits share similar geometric and dimensional characteristics. Lobes are grouped into two distinct populations of geometries that can be related to basin floor topography. The first population corresponds to areally extensive but thin lobes (average width 14 km × length 35 km × thickness 12 m) that were deposited onto low relief basin floor areas. Examples of such systems include the Tanqua Karoo, the Amazon, and the Zaïre systems. The second population corresponds to areally smaller but thicker lobes (average width 5 km × length 8 km × thickness 30 m) that were deposited into settings with higher amplitude of relief, like in the Corsican trough, the Kutai basin, and offshore Nigeria. The two populations of lobe types, however, share similar volumes (a narrow range around 1 or 2 km 3), which suggests that there is a control to the total volume of sediment that individual lobes can reach before they shift to a new locus of deposition. This indicates that the extrinsic processes control the number of lobes deposited per unit time rather than their dimensions. Two alternative hypotheses are presented to explain the similarities in lobe volumes calculated from the six very different systems. The first states that
Hickman, Dwayne A. [ACI Services, Inc., Cambridge, OH (United States); Slupsky, John [Kvaerner Process Systems, Calgary, Alberta (Canada); Chrisman, Bruce M.; Hurley, Tom J. [Cooper Energy Services, Oklahoma City, OK (United States). Ajax Division
2003-07-01
Automated, variable volume unloaders provide the ability to smoothly load/unload reciprocating compressors to maintain ideal operations in ever-changing environments. Potential advantages provided by this load control system include: maximizing unit capacity, optimizing power economy, maintaining low exhaust emissions, and maintaining process suction and discharge pressures. Obstacles foreseen include: reliability, stability, serviceability and automation integration. Results desired include: increased productivity for the compressor and its operators, increased up time, and more stable process control. This presentation covers: system design features with descriptions of how different types of the devices were developed, initial test data, and how they can be effectively operated; three actual-case studies detailing the reasons why automated, hydraulically controlled, variable volume, head-end unloaders were chosen over other types of unloading devices; sophisticated software used in determining the device sizing and predicted performance; mechanical and field considerations; installation, serviceability and operating considerations; device control issues, including PC and PLC considerations; monitoring of actual performance and comparison of such with predicted performance; analysis of mechanical reliability and stability; and preliminary costs versus return on investment analysis. (author)
Nevens, T.D.; Culbertson, W.J. Jr.; Wallace, J.R.; Taylor, G.C.; Jovanovich, A.P.; Prien, C.H.; Hicks, R.E.; Probstein, R.F.; Domahidy, G.
1979-07-01
The pollution control costs for a commercial oil shale industry were determined in a joint effort by Denver Research Institute, Water Purification Associates of Cambridge, and Stone and Webster Engineering of Boston and Denver. Four commercial oil shale processes were considered. The results in terms of cost per barrel of syncrude oil are predicted to be as follows: Paraho Process, $0.67 to $1.01; TOSCO II Process, $1.43 to $1.91; MIS Process, $2.02 to $3.03; and MIS/Lurgi-Ruhrgas Process, $1.68 to $2.43. Alternative pollution control equipment and integrated pollution control strategies were considered and optimal systems selected for each full-scale plant. A detailed inventory of equipment (along with the rationale for selection), a detailed description of control strategies, itemized costs and predicted emission levels are presented for each process. Capital and operating cost data are converted to a cost per barrel basis using detailed economic evaluation procedures. Ranges of cost are determined using a subjective self-assessment of uncertainty approach. An accepted methodology for probability encoding was used, and cost ranges are presented as subjective probability distributions. Volume I presents the detailed engineering results. Volume II presents the detailed analysis of uncertainty in the predicted costs.
MODELLING AND CONTROL OF CONTINUOUS STIRRED TANK REACTOR WITH PID CONTROLLER
Artur Wodołażski
2016-09-01
Full Text Available This paper presents a model of dynamics control for continuous stirred tank reactor (CSTR in methanol synthesis in a three-phase system. The reactor simulation was carried out for steady and transient state. Efficiency ratio to achieve maximum performance of the product per reactor unit volume was calculated. Reactor dynamics simulation in closed loop allowed to received data for tuning PID controller (proportional-integral-derivative. The results of the regulation process allow to receive data for optimum reactor production capacity, along with local hot spots eliminations or temperature runaway.
Recreation of architectural structures using procedural modeling based on volumes
Santiago Barroso Juan
2013-11-01
Full Text Available While the procedural modeling of buildings and other architectural structures has evolved very significantly in recent years, there is noticeable absence of high-level tools that allow a designer, an artist or an historian, creating important buildings or architectonic structures in a particular city. In this paper we present a tool for creating buildings in a simple and clear, following rules that use the language and methodology of creating their own buildings, and hiding the user the algorithmic details of the creation of the model.
Model-Based Power Plant Master Control
Boman, Katarina; Thomas, Jean; Funkquist, Jonas
2010-08-15
The main goal of the project has been to evaluate the potential of a coordinated master control for a solid fuel power plant in terms of tracking capability, stability and robustness. The control strategy has been model-based predictive control (MPC) and the plant used in the case study has been the Vattenfall power plant Idbaecken in Nykoeping. A dynamic plant model based on nonlinear physical models was used to imitate the true plant in MATLAB/SIMULINK simulations. The basis for this model was already developed in previous Vattenfall internal projects, along with a simulation model of the existing control implementation with traditional PID controllers. The existing PID control is used as a reference performance, and it has been thoroughly studied and tuned in these previous Vattenfall internal projects. A turbine model was developed with characteristics based on the results of steady-state simulations of the plant using the software EBSILON. Using the derived model as a representative for the actual process, an MPC control strategy was developed using linearization and gain-scheduling. The control signal constraints (rate of change) and constraints on outputs were implemented to comply with plant constraints. After tuning the MPC control parameters, a number of simulation scenarios were performed to compare the MPC strategy with the existing PID control structure. The simulation scenarios also included cases highlighting the robustness properties of the MPC strategy. From the study, the main conclusions are: - The proposed Master MPC controller shows excellent set-point tracking performance even though the plant has strong interactions and non-linearity, and the controls and their rate of change are bounded. - The proposed Master MPC controller is robust, stable in the presence of disturbances and parameter variations. Even though the current study only considered a very small number of the possible disturbances and modelling errors, the considered cases are
THE INTERNAL CONTROL MODELS IN ROMANIA
TEODORESCU CRISTIAN DRAGOȘ
2015-06-01
Full Text Available Internal control is indissolubly linked to business and accounting. Throughout history, domestic and international trade has grown exponentially, which has led to an increasing complexity of internal control, to new methods and techniques to control the business. The literature has presented the first models of internal control in the Sumerian period (3600 - 3200 BC, and the emergence and development of internal control in Egypt, Persia, Greek and Roman Empire, in the Middle Ages till modern times. The purpose of this article is to present the models of internal control in Romania, starting from the principles of the classical model of internal control (COSO model. For a better understanding of the implication of internal control in terms of public and private sector, I have structured the article in the following parts: (a the definition of internal control in the literature; (b the presentation of the COSO model; (c internal control and internal audit in public institutions; (d internal control issues in accounting regulations on the individual and consolidated annual financial statements; (e internal / managerial control; (f conclusions.
Storm Water Management Model Reference Manual Volume II – Hydraulics
SWMM is a dynamic rainfall-runoff simulation model used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. The runoff component of SWMM operates on a collection of subcatchment areas that receive precipitation and gene...
Modeling Degradation in Solid Oxide Electrolysis Cells - Volume II
Manohar Motwani
2011-09-01
Idaho National Laboratory has an ongoing project to generate hydrogen from steam using solid oxide electrolysis cells (SOECs). To accomplish this, technical and degradation issues associated with the SOECs will need to be addressed. This report covers various approaches being pursued to model degradation issues in SOECs. An electrochemical model for degradation of SOECs is presented. The model is based on concepts in local thermodynamic equilibrium in systems otherwise in global thermodynamic non-equilibrium. It is shown that electronic conduction through the electrolyte, however small, must be taken into account for determining local oxygen chemical potential,, within the electrolyte. The within the electrolyte may lie out of bounds in relation to values at the electrodes in the electrolyzer mode. Under certain conditions, high pressures can develop in the electrolyte just near the oxygen electrode/electrolyte interface, leading to oxygen electrode delamination. These predictions are in accordance with the reported literature on the subject. Development of high pressures may be avoided by introducing some electronic conduction in the electrolyte. By combining equilibrium thermodynamics, non-equilibrium (diffusion) modeling, and first-principles, atomic scale calculations were performed to understand the degradation mechanisms and provide practical recommendations on how to inhibit and/or completely mitigate them.
Kawashima, Mitsuhiko; Ogino, Takashi; Hayashi, Ryuichi; Ishikura, Satoshi; Nihei, Keiji; Ito, Yoshinori; Ikeda, Hiroshi; Ebihara, Satoshi [National Cancer Center, Kashiwa, Chiba (Japan). Hospital East; Itai, Yuji
2001-05-01
The aim was to study the influence of postsurgical gross residual tumor volume on local control of maxillary sinus cancer treated with radiotherapy combined with debulking surgery. Forty-three patients who underwent combined surgery and radiotherapy (50-72 Gy, median 60 Gy) for squamous cell carcinoma of the maxillary sinus were reviewed. Gross residual tumor volume (GRTV) after surgery was measured on computed tomograms obtained during the radiotherapy planning. Patients were classified according to GRTV as follows: group AA, GRTV=0 (microscopic residual, n=2); group A, GRTV <10 cm{sup 3} (n=24); group B, 10-40 cm{sup 3} (n=9); and group C, {>=}40 cm{sup 3} (n=8). The relationship between local control and GRTV was analyzed using univariate and multivariate analysis. The 2-year local control rate for all patients was 62%. The differences in local control rates between groups AA, A and B were not significant (P<0.05), but the rate was significantly lower in group C than in the other groups (69% at 2 years vs 31% at 1 year, P<0.001). Multivariate analysis showed that GRTV (P=0.002) and histological differentiation (poorly differentiated histology was favorable, P=0.035) were independent prognostic factors and that intraarterial chemotherapy and administered total dose were not. Local control in groups A and B significantly depended on the total dose of radiotherapy, with 2-year control rates of patients receiving 50 Gy (n=6) and {>=}60 Gy (n=27) of 17% vs 79%, respectively (P<0.001). Our data suggest that adequate, not complete, debulking associated with a total radiotherapy dose of {>=}60 Gy can provide satisfactory local control for patients with squamous cell carcinoma of the maxillary sinus. (author)
Complex system modelling and control through intelligent soft computations
Azar, Ahmad
2015-01-01
The book offers a snapshot of the theories and applications of soft computing in the area of complex systems modeling and control. It presents the most important findings discussed during the 5th International Conference on Modelling, Identification and Control, held in Cairo, from August 31-September 2, 2013. The book consists of twenty-nine selected contributions, which have been thoroughly reviewed and extended before their inclusion in the volume. The different chapters, written by active researchers in the field, report on both current theories and important applications of soft-computing. Besides providing the readers with soft-computing fundamentals, and soft-computing based inductive methodologies/algorithms, the book also discusses key industrial soft-computing applications, as well as multidisciplinary solutions developed for a variety of purposes, like windup control, waste management, security issues, biomedical applications and many others. It is a perfect reference guide for graduate students, r...
Control Valve Stiction Identification, Modelling, Quantification and Control - A Review
Srinivasan Arumugam
2011-09-01
Full Text Available Most of the processes found in process industries exhibit undesirable nonlinearity due to backlash, saturation, hysteresis, stiction (friction, dead-zone and stuck-fault existing in control valves. The control valve is the actuator for most process control loops and, as the only moving part in the loop, its function is to implement the control action. If the control valve malfunctions, the performance of the control loop is likely to deteriorate, no matter how good the controller is. Commonly encountered control valve problems include nonlinear responses to the demand signal caused by effects such as stiction, dead-band or saturation. Because of these problems, the control loop may be oscillatory, which in turn may cause oscillations in many process variables causing a range of operational problems including increased valve wear. Understanding nonlinear behaviour of control valves in order to maintain the quality of the end products in the industry, this review article surveys the identification, modelling, estimation and design of dynamic models of stiction nonlinearity and providing appropriate controller to obtain optimum responses of the process. The primary objective of this work is to present state-of-art-review of common nonlinear problems associated with mechanical and chemical processes for encouraging researchers, practicing engineers working in this field, so that readers can invent their goals for future research work on nonlinear systems identification and control.
Felix, M.V.; Morones, R.; Castano, V.M.
2004-01-01
Three semi-empirical positron stationary Quantum Models were developed for the study of nanoporosity in a wide range of solid porous materials. The cubic, conic and cylindrical well potentials were considered and their geometric parameters related to the Positron Annihilation LifeTime (PALT) measurements. If a conic or a cubic symmetry is assumed, a resonance lifetime phenomenon was found, which enables proposal of a technique to catch positrons in free volume sites. In the cylindrical case, an alternative method to determine free volume sizes in materials was developed. The free volume equations of these new models were then compared to the well-known and widely utilised Spherical Free Volume Model (SFVM) and remarkable differences were found. A strong variation of the free volume size-positron lifetime relation with the geometry involved was observed and a remarkable dependence of the electron layer thickness parameter ΔR with the hole-shape under study and with the nature of the material considered. The mathematical functions appearing in the conic and cylindrical cases are the superposition of Bessel functions of the first kind and trigonometric functions in the cubic case. Generalised free volume diagrams were constructed and a brief geometrical scheme of the diverse cases considered was obtained. (author)
PI controller based model reference adaptive control for nonlinear
user
Keywords: Model Reference Adaptive Controller (MRAC), Artificial Neural ... attention, and many new approaches have been applied to practical process .... effectiveness of proposed method, it is compared with the simulation results of the ...
Fault Tolerant Control Using Gaussian Processes and Model Predictive Control
Yang Xiaoke
2015-03-01
Full Text Available Essential ingredients for fault-tolerant control are the ability to represent system behaviour following the occurrence of a fault, and the ability to exploit this representation for deciding control actions. Gaussian processes seem to be very promising candidates for the first of these, and model predictive control has a proven capability for the second. We therefore propose to use the two together to obtain fault-tolerant control functionality. Our proposal is illustrated by several reasonably realistic examples drawn from flight control.
Smirnova, E.S.; Chuvil'deev, V.N.
1998-01-01
The model is suggested which describes the influence of large-angle grain boundary migration on a diffusion controlled creep rate in polycrystalline materials (Coble creep). The model is based on the concept about changing the value of migrating boundary free volume when introducing dislocations distributed over the grain bulk into this boundary. Expressions are obtained to calculate the grain boundary diffusion coefficient under conditions of boundary migration and the parameter, which characterized the value of Coble creep acceleration. A comparison is made between calculated and experimental data for Cd, Co and Fe
Introduction to the Special Volume on "Ecology and Ecological Modeling in R"
Kneib, Thomas; Petzoldt, Thomas
2007-01-01
The third special volume in the "Foometrics in R" series of the Journal of Statistical Software collects a number of contributions describing statistical methodology and corresponding implementations related to ecology and ecological modelling. The scope of the papers ranges from theoretical ecology and ecological modelling to statistical methodology relevant for data analyses in ecological applications.
Flexible AC transmission systems modelling and control
Zhang, Xiao-Ping; Pal, Bikash
2012-01-01
The extended and revised second edition of this successful monograph presents advanced modeling, analysis and control techniques of Flexible AC Transmission Systems (FACTS). The book covers comprehensively a range of power-system control problems: from steady-state voltage and power flow control, to voltage and reactive power control, to voltage stability control, to small signal stability control using FACTS controllers. In the six years since the first edition of the book has been published research on the FACTS has continued to flourish while renewable energy has developed into a mature and
MARS CODE MANUAL VOLUME V: Models and Correlations
Chung, Bub Dong; Bae, Sung Won; Lee, Seung Wook; Yoon, Churl; Hwang, Moon Kyu; Kim, Kyung Doo; Jeong, Jae Jun
2010-02-01
Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This models and correlations manual provides a complete list of detailed information of the thermal-hydraulic models used in MARS, so that this report would be very useful for the code users. The overall structure of the manual is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS3.1. MARS3.1 development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible
Unreachable Setpoints in Model Predictive Control
Rawlings, James B.; Bonné, Dennis; Jørgensen, John Bagterp
2008-01-01
In this work, a new model predictive controller is developed that handles unreachable setpoints better than traditional model predictive control methods. The new controller induces an interesting fast/slow asymmetry in the tracking response of the system. Nominal asymptotic stability of the optimal...... steady state is established for terminal constraint model predictive control (MPC). The region of attraction is the steerable set. Existing analysis methods for closed-loop properties of MPC are not applicable to this new formulation, and a new analysis method is developed. It is shown how to extend...
Winkelman, John W; Benson, Kathleen L; Buxton, Orfeu M; Lyoo, In Kyoon; Yoon, Sujung; O'Connor, Shawn; Renshaw, Perry F
2010-06-01
A recent pilot study reported that hippocampal volume (HV) was reduced in patients with primary insomnia (PI) relative to normal sleepers. Loss of HV in PI might be due to chronic hyperarousal and/or chronic sleep debt. The aim of this study was to replicate the earlier pilot report while employing a larger sample, more rigorous screening criteria, and objective sleep data. This cross-sectional design included community recruits meeting DSM-IV criteria for PI (n=20, 10 males, mean age 39.3+/-8.7) or good sleeper controls (n=15, 9 males, mean age 38.8+/-5.3). All subjects were unmedicated and rigorously screened to exclude comorbid psychiatric and medical illness. PI subjects underwent overnight polysomnography to screen for sleep-related breathing and movement disorders. HV and total brain volumes were derived by MRI employing a Siemens/Trio scanner operating at 3 Tesla. Data also included 2 weeks of sleep diaries and wrist actigraphy. Mean HV was 4322.0+/-299.7 mm(3) for the good sleeper controls and 4601.55+/-537.4 mm(3) for the PI group. The dependent variable, HV, was analyzed by ANCOVA. Main effects were diagnosis and gender; whole brain volume served as the covariate. Although the overall model was significant (F=6.3, p=0.001), the main effects of diagnosis (F=2.14) and gender (F=0.04) were not significant. The covariate of whole brain volume was significant (F=5.74, p=0.023) as was the interaction of diagnosis with gender (F=10.22, p=0.003), with male insomniacs having larger HVs than male controls. This study did not replicate a previously published report of HV loss in primary insomnia. Differences between our finding and the previous report might be due to sample composition and method of MRI assessment. Furthermore, we demonstrated no objective differences between the controls and PIs in actigraphic measures of sleep maintenance. Within the PIs, however, actigraphic measures of poor sleep maintenance were associated with smaller HV. Copyright 2010
Effect of Inhomogeneity correction for lung volume model in TPS
Chung, Se Young; Lee, Sang Rok; Kim, Young Bum; Kwon, Young Ho
2004-01-01
The phantom that includes high density materials such as steel was custom-made to fix lung and bone in order to evaluation inhomogeneity correction at the time of conducting radiation therapy to treat lung cancer. Using this, values resulting from the inhomogeneous correction algorithm are compared on the 2 and 3 dimensional radiation therapy planning systems. Moreover, change in dose calculation was evaluated according to inhomogeneous by comparing with the actual measurement. As for the image acquisition, inhomogeneous correction phantom(Pig's vertebra, steel(8.21 g/cm 3 ), cork(0.23 g/cm 3 )) that was custom-made and the CT(Volume zoom, Siemens, Germany) were used. As for the radiation therapy planning system, Marks Plan(2D) and XiO(CMS, USA, 3D) were used. To compare with the measurement value, linear accelerator(CL/1800, Varian, USA) and ion chamber were used. Image, obtained from the CT was used to obtain point dose and dose distribution from the region of interest (ROI) while on the radiation therapy planning device. After measurement was conducted under the same conditions, value on the treatment planning device and measured value were subjected to comparison and analysis. And difference between the resulting for the evaluation on the use (or non-use) of inhomogeneity correction algorithm, and diverse inhomogeneity correction algorithm that is included in the radiation therapy planning device was compared as well. As result of comparing the results of measurement value on the region of interest within the inhomogeneity correction phantom and the value that resulted from the homogeneous and inhomogeneous correction, gained from the therapy planning device, margin of error of the measurement value and inhomogeneous correction value at the location 1 of the lung showed 0.8% on 2D and 0.5% on 3D. Margin of error of the measurement value and inhomogeneous correction value at the location 1 of the steel showed 12% on 2D and 5% on 3D, however, it is possible to
Model based development of engine control algorithms
Dekker, H.J.; Sturm, W.L.
1996-01-01
Model based development of engine control systems has several advantages. The development time and costs are strongly reduced because much of the development and optimization work is carried out by simulating both engine and control system. After optimizing the control algorithm it can be executed
Model predictive Controller for Mobile Robot
Alireza Rezaee
2017-01-01
This paper proposes a Model Predictive Controller (MPC) for control of a P2AT mobile robot. MPC refers to a group of controllers that employ a distinctly identical model of process to predict its future behavior over an extended prediction horizon. The design of a MPC is formulated as an optimal control problem. Then this problem is considered as linear quadratic equation (LQR) and is solved by making use of Ricatti equation. To show the effectiveness of the proposed method this controller is...
Review of models used for determining consequences of UF6 release: Model evaluation report. Volume 2
Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O.
1997-11-01
Three uranium hexafluoride-(UF 6 -) specific models--HGSYSTEM/UF 6 , Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF 6 released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF 6 -specific models, using field data on releases of UF 6 and other heavy gases. Predictions from the HGSYSTEM/UF 6 and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF 6 -specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF 6 reaction with water
Ultra-low-volume space sprays in mosquito control: a critical review.
Bonds, J A S
2012-06-01
The availability of tools to control mosquito (Diptera:Culicidae) vectors that transmit disease is often limited by a variety of economic, environmental and social issues. In emergency conditions (epidemics, hurricanes, floods etc.), the application of pesticides as space sprays (either by ground or air) is the common method of choice in order to rapidly limit adult local mosquito production in the affected area. Space spray application now employs ultra-low-volume technology for the control of adult mosquitoes. However, the use of space sprays often raises social and environmental concerns by the general public that is served. This review will define and illustrate modern ultra-low-volume technology for the purpose of application as a space spray, as well as describing the engineering controls that have been developed to minimize the environmental impact. The primary social concern is validity and efficacy of application. To address this point, the review will attempt to synthesize the global literature to address the effectiveness of space sprays to significantly impact mosquito vectors in relation to human disease. © 2012 The Author. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.
Integrated identification, modeling and control with applications
Shi, Guojun
This thesis deals with the integration of system design, identification, modeling and control. In particular, six interdisciplinary engineering problems are addressed and investigated. Theoretical results are established and applied to structural vibration reduction and engine control problems. First, the data-based LQG control problem is formulated and solved. It is shown that a state space model is not necessary to solve this problem; rather a finite sequence from the impulse response is the only model data required to synthesize an optimal controller. The new theory avoids unnecessary reliance on a model, required in the conventional design procedure. The infinite horizon model predictive control problem is addressed for multivariable systems. The basic properties of the receding horizon implementation strategy is investigated and the complete framework for solving the problem is established. The new theory allows the accommodation of hard input constraints and time delays. The developed control algorithms guarantee the closed loop stability. A closed loop identification and infinite horizon model predictive control design procedure is established for engine speed regulation. The developed algorithms are tested on the Cummins Engine Simulator and desired results are obtained. A finite signal-to-noise ratio model is considered for noise signals. An information quality index is introduced which measures the essential information precision required for stabilization. The problems of minimum variance control and covariance control are formulated and investigated. Convergent algorithms are developed for solving the problems of interest. The problem of the integrated passive and active control design is addressed in order to improve the overall system performance. A design algorithm is developed, which simultaneously finds: (i) the optimal values of the stiffness and damping ratios for the structure, and (ii) an optimal output variance constrained stabilizing
Blood products, volume control, and renal support in the coagulopathy of liver disease.
Argo, Curtis K; Balogun, Rasheed A
2009-02-01
Plasma-based products are commonly used in patients who have chronic liver disease to treat perceived coagulopathy despite unproven efficacy and potentially severe risks, such as transfusion-related acute lung injury, which carries a high mortality rate. Moreover, volume expansion may acutely worsen portal hypertension and increase bleeding from the collateral portal vascular bed. Although factor replacement therapy may be warranted in selected situations, its use should be restricted because of the limitations of target tests, such as international normalized ratio, which poorly reflects presence of bleeding diatheses in patients who have cirrhosis. Renal replacement therapies are frequent adjuncts in patients who have cirrhosis and are acutely decompensated, and may correct uremia-related bleeding diathesis and assist in controlling vascular volume, although they are generally limited to use as a bridge to liver transplantation. Novel extracorporeal therapies are emerging and may also have significant interaction with the hemostatic system. Volume contraction and blood conservation therapies are relatively new and promising approaches to reduce use of blood products in liver transplantation.
Finite-volume spectra of the Lee-Yang model
Bajnok, Zoltan [MTA Lendület Holographic QFT Group, Wigner Research Centre for Physics,H-1525 Budapest 114, P.O.B. 49 (Hungary); Deeb, Omar el [MTA Lendület Holographic QFT Group, Wigner Research Centre for Physics,H-1525 Budapest 114, P.O.B. 49 (Hungary); Physics Department, Faculty of Science, Beirut Arab University (BAU),Beirut (Lebanon); Pearce, Paul A. [School of Mathematics and Statistics, University of Melbourne,Parkville, Victoria 3010 (Australia)
2015-04-15
We consider the non-unitary Lee-Yang minimal model M(2,5) in three different finite geometries: (i) on the interval with integrable boundary conditions labelled by the Kac labels (r,s)=(1,1),(1,2), (ii) on the circle with periodic boundary conditions and (iii) on the periodic circle including an integrable purely transmitting defect. We apply φ{sub 1,3} integrable perturbations on the boundary and on the defect and describe the flow of the spectrum. Adding a Φ{sub 1,3} integrable perturbation to move off-criticality in the bulk, we determine the finite size spectrum of the massive scattering theory in the three geometries via Thermodynamic Bethe Ansatz (TBA) equations. We derive these integral equations for all excitations by solving, in the continuum scaling limit, the TBA functional equations satisfied by the transfer matrices of the associated A{sub 4} RSOS lattice model of Forrester and Baxter in Regime III. The excitations are classified in terms of (m,n) systems. The excited state TBA equations agree with the previously conjectured equations in the boundary and periodic cases. In the defect case, new TBA equations confirm previously conjectured transmission factors.
Combining 3d Volume and Mesh Models for Representing Complicated Heritage Buildings
Tsai, F.; Chang, H.; Lin, Y.-W.
2017-08-01
This study developed a simple but effective strategy to combine 3D volume and mesh models for representing complicated heritage buildings and structures. The idea is to seamlessly integrate 3D parametric or polyhedral models and mesh-based digital surfaces to generate a hybrid 3D model that can take advantages of both modeling methods. The proposed hybrid model generation framework is separated into three phases. Firstly, after acquiring or generating 3D point clouds of the target, these 3D points are partitioned into different groups. Secondly, a parametric or polyhedral model of each group is generated based on plane and surface fitting algorithms to represent the basic structure of that region. A "bare-bones" model of the target can subsequently be constructed by connecting all 3D volume element models. In the third phase, the constructed bare-bones model is used as a mask to remove points enclosed by the bare-bones model from the original point clouds. The remaining points are then connected to form 3D surface mesh patches. The boundary points of each surface patch are identified and these boundary points are projected onto the surfaces of the bare-bones model. Finally, new meshes are created to connect the projected points and original mesh boundaries to integrate the mesh surfaces with the 3D volume model. The proposed method was applied to an open-source point cloud data set and point clouds of a local historical structure. Preliminary results indicated that the reconstructed hybrid models using the proposed method can retain both fundamental 3D volume characteristics and accurate geometric appearance with fine details. The reconstructed hybrid models can also be used to represent targets in different levels of detail according to user and system requirements in different applications.
Model predictive controller design of hydrocracker reactors
GÖKÇE, Dila
2011-01-01
This study summarizes the design of a Model Predictive Controller (MPC) in Tüpraş, İzmit Refinery Hydrocracker Unit Reactors. Hydrocracking process, in which heavy vacuum gasoil is converted into lighter and valuable products at high temperature and pressure is described briefly. Controller design description, identification and modeling studies are examined and the model variables are presented. WABT (Weighted Average Bed Temperature) equalization and conversion increase are simulate...
NONE
1995-02-17
The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A.
1995-01-01
The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A
Test Functions for Three-Dimensional Control-Volume Mixed Finite-Element Methods on Irregular Grids
Naff, R. L; Russell, T. F; Wilson, J. D
2000-01-01
.... For control-volume mixed finite-element methods, vector shape functions are used to approximate the distribution of velocities across cells and vector test functions are used to minimize the error...
Lane, F
1996-01-01
On August 1, 1995, the Under Secretary of Defense (Comptroller) released for implementation Financial Management Regulation, volume 14, "Administrative Control of Funds and Antideficiency Act Violations," August 1, 1995...
Constantin, Julian Gelman; Schneider, Matthias; Corti, Horacio R
2016-06-09
The glass transition temperature of trehalose, sucrose, glucose, and fructose aqueous solutions has been predicted as a function of the water content by using the free volume/percolation model (FVPM). This model only requires the molar volume of water in the liquid and supercooled regimes, the molar volumes of the hypothetical pure liquid sugars at temperatures below their pure glass transition temperatures, and the molar volumes of the mixtures at the glass transition temperature. The model is simplified by assuming that the excess thermal expansion coefficient is negligible for saccharide-water mixtures, and this ideal FVPM becomes identical to the Gordon-Taylor model. It was found that the behavior of the water molar volume in trehalose-water mixtures at low temperatures can be obtained by assuming that the FVPM holds for this mixture. The temperature dependence of the water molar volume in the supercooled region of interest seems to be compatible with the recent hypothesis on the existence of two structure of liquid water, being the high density liquid water the state of water in the sugar solutions. The idealized FVPM describes the measured glass transition temperature of sucrose, glucose, and fructose aqueous solutions, with much better accuracy than both the Gordon-Taylor model based on an empirical kGT constant dependent on the saccharide glass transition temperature and the Couchman-Karasz model using experimental heat capacity changes of the components at the glass transition temperature. Thus, FVPM seems to be an excellent tool to predict the glass transition temperature of other aqueous saccharides and polyols solutions by resorting to volumetric information easily available.
Assessment of volume and leak measurements during CPAP using a neonatal lung model
Fischer, H S; Roehr, C C; Proquitté, H; Wauer, R R; Schmalisch, G
2008-01-01
Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen and Löwenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2–10 ml, 20–100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error ±SD was 3.5 ± 2.6% (2–10 ml) and 5.9 ± 0.7% (20–60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F i O 2 caused the measured tidal volume to increase by up to 25% (F i O 2 = 1.0). The relative error ±SD of the leak measurements was −0.2 ± 11.9%. For leaks >19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F i O 2 >0.4 and for leaks >19%, a numerical correction of the displayed volume should be performed
Assessment of volume and leak measurements during CPAP using a neonatal lung model.
Fischer, H S; Roehr, C C; Proquitté, H; Wauer, R R; Schmalisch, G
2008-01-01
Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen & Löwenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2-10 ml, 20-100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error +/-SD was 3.5 +/- 2.6% (2-10 ml) and 5.9 +/- 0.7% (20-60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F(i)O(2) caused the measured tidal volume to increase by up to 25% (F(i)O(2) = 1.0). The relative error +/- SD of the leak measurements was -0.2 +/- 11.9%. For leaks > 19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F(i)O(2) > 0.4 and for leaks > 19%, a numerical correction of the displayed volume should be performed.
Mathematical Ship Modeling for Control Applications
Perez, Tristan; Blanke, Mogens
2002-01-01
In this report, we review the models for describing the motion of a ship in four degrees of freedom suitable for control applications. We present the hydrodynamic models of two ships: a container and a multi-role naval vessel. The models are based on experimental results in the four degrees...
Hongmei eWang
2015-03-01
Full Text Available Objective: Internet gaming disorder (IGD has been investigated by many behavioral and neuroimaging studies, for it has became one of the main behavior disorders among adolescents. However, few studies focused on the relationship between alteration of gray matter volume (GMV and cognitive control feature in IGD adolescents. Methods: Twenty-eight participants with IAD and twenty-eight healthy age and gender matched controls participated in the study. Brain morphology of adolescents with IGD and healthy controls was investigated using an optimized voxel-based morphometry (VBM technique. Cognitive control performances were measured by Stroop task, and correlation analysis was performed between brain structural change and behavioral performance in IGD group. Results: The results showed that GMV of the bilateral anterior cingulate cortex (ACC, precuneus, supplementary motor area (SMA, superior parietal cortex, left dorsal lateral prefrontal cortex (DLPFC, left insula, and bilateral cerebellum decreased in the IGD participants compared with healthy controls. Moreover, GMV of the ACC was negatively correlated with the incongruent response errors of Stroop task in IGD group. Conclusion: Our results suggest that the alteration of GMV is associated with the performance change of cognitive control in adolescents with IGD, which indicating substantial brain image effects induced by IGD.
Flexible AC transmission systems. Modelling and control
Zhang, Xiao-Ping [Birmingham Univ. (United Kingdom); Rehtanz, Christian [Technische Univ. Dortmund (Germany); Pal, Bikash [Imperial College, London (United Kingdom)
2012-11-01
This monograph presents advanced modelling, analysis and control techniques of FACTS. These topics reflect the recent research and development of FACTS controllers, and anticipate the future applications of FACTS in power systems. The book covers comprehensively a range of power-system control problems: from steady-state voltage and power flow control, to voltage and reactive power control, to voltage stability control, to small signal stability control using FACTS controllers. The book presents the modelling of the latest FACTS controllers for power flow control, compensation and power quality (IPFC, GUPF, VSC HVDC and M-VSCHVDC, etc.) in power system analysis. The selection is evaluated by the actual and likely future practical relevance of each. The material is derived mainly from the research and industrial development in which the authors have been heavily involved. The book is timely and of great value to power engineering engineers and students of modelling, simulations and control design of FACTS for a broad practical range of power system operation, planning and control problems.
Tanderup, Kari; Fokdal, Lars Ulrik; Sturdza, Alina
2016-01-01
-center patient series (retroEMBRACE). Materials and methods This study analyzed 488 locally advanced cervical cancer patients treated with external beam radiotherapy ± chemotherapy combined with IGABT. Brachytherapy contouring and reporting was according to ICRU/GEC-ESTRO recommendations. The Cox Proportional...... Hazards model was applied to analyze the effect on local control of dose-volume metrics as well as overall treatment time (OTT), dose rate, chemotherapy, and tumor histology. Results With a median follow up of 46 months, 43 local failures were observed. Dose (D90) to the High Risk Clinical Target Volume...
Precise determination of universal finite volume observables in the Gross-Neveu model
Korzec, T.
2007-01-26
The Gross-Neveu model is a quantum field theory in two space time dimensions that shares many features with quantum chromo dynamics. In this thesis the continuum model and its discretized versions are reviewed and a finite volume renormalization scheme is introduced and tested. Calculations in the limit of infinitely many fermion flavors as well as perturbative computations are carried out. In extensive Monte-Carlo simulations of the one flavor and the four flavor lattice models with Wilson fermions a set of universal finite volume observables is calculated to a high precision. In the one flavor model which is equivalent to the massless Thirring model the continuum extrapolated Monte-Carlo results are confronted with an exact solution of the model. (orig.)
Precise determination of universal finite volume observables in the Gross-Neveu model
Korzec, T.
2007-01-01
The Gross-Neveu model is a quantum field theory in two space time dimensions that shares many features with quantum chromo dynamics. In this thesis the continuum model and its discretized versions are reviewed and a finite volume renormalization scheme is introduced and tested. Calculations in the limit of infinitely many fermion flavors as well as perturbative computations are carried out. In extensive Monte-Carlo simulations of the one flavor and the four flavor lattice models with Wilson fermions a set of universal finite volume observables is calculated to a high precision. In the one flavor model which is equivalent to the massless Thirring model the continuum extrapolated Monte-Carlo results are confronted with an exact solution of the model. (orig.)
Model predictive control classical, robust and stochastic
Kouvaritakis, Basil
2016-01-01
For the first time, a textbook that brings together classical predictive control with treatment of up-to-date robust and stochastic techniques. Model Predictive Control describes the development of tractable algorithms for uncertain, stochastic, constrained systems. The starting point is classical predictive control and the appropriate formulation of performance objectives and constraints to provide guarantees of closed-loop stability and performance. Moving on to robust predictive control, the text explains how similar guarantees may be obtained for cases in which the model describing the system dynamics is subject to additive disturbances and parametric uncertainties. Open- and closed-loop optimization are considered and the state of the art in computationally tractable methods based on uncertainty tubes presented for systems with additive model uncertainty. Finally, the tube framework is also applied to model predictive control problems involving hard or probabilistic constraints for the cases of multiplic...
Binzoni, T; Leung, T S; Ruefenacht, D; Delpy, D T
2006-01-01
Based on quasi-elastic scattering theory (and random walk on a lattice approach), a model of laser-Doppler flowmetry (LDF) has been derived which can be applied to measurements in large tissue volumes (e.g. when the interoptode distance is >30 mm). The model holds for a semi-infinite medium and takes into account the transport-corrected scattering coefficient and the absorption coefficient of the tissue, and the scattering coefficient of the red blood cells. The model holds for anisotropic scattering and for multiple scattering of the photons by the moving scatterers of finite size. In particular, it has also been possible to take into account the simultaneous presence of both Brownian and pure translational movements. An analytical and simplified version of the model has also been derived and its validity investigated, for the case of measurements in human skeletal muscle tissue. It is shown that at large optode spacing it is possible to use the simplified model, taking into account only a 'mean' light pathlength, to predict the blood flow related parameters. It is also demonstrated that the 'classical' blood volume parameter, derived from LDF instruments, may not represent the actual blood volume variations when the investigated tissue volume is large. The simplified model does not need knowledge of the tissue optical parameters and thus should allow the development of very simple and cost-effective LDF hardware
Parametric Analysis of Flexible Logic Control Model
Lihua Fu
2013-01-01
Full Text Available Based on deep analysis about the essential relation between two input variables of normal two-dimensional fuzzy controller, we used universal combinatorial operation model to describe the logic relationship and gave a flexible logic control method to realize the effective control for complex system. In practical control application, how to determine the general correlation coefficient of flexible logic control model is a problem for further studies. First, the conventional universal combinatorial operation model has been limited in the interval [0,1]. Consequently, this paper studies a kind of universal combinatorial operation model based on the interval [a,b]. And some important theorems are given and proved, which provide a foundation for the flexible logic control method. For dealing reasonably with the complex relations of every factor in complex system, a kind of universal combinatorial operation model with unequal weights is put forward. Then, this paper has carried out the parametric analysis of flexible logic control model. And some research results have been given, which have important directive to determine the values of the general correlation coefficients in practical control application.
1980-06-01
These proceedings document the presentations given at the Second Environmental Control Symposium. Symposium presentations highlighted environmental control activities which span the entire DOE. Volume II contains papers relating to: environmental control aspects of nuclear energy use and development; nuclear waste management; renewable energy sources; transportation and building conservation (fuel economy, gasohol, building standards, and industry); and geothermal energy, power transmission, and energy storage
None
1980-06-01
These proceedings document the presentations given at the Second Environmental Control Symposium. Symposium presentations highlighted environmental control activities which span the entire DOE. Volume II contains papers relating to: environmental control aspects of nuclear energy use and development; nuclear waste management; renewable energy sources; transportation and building conservation (fuel economy, gasohol, building standards, and industry); and geothermal energy, power transmission, and energy storage. (DMC)
Klobe, L.E. [ed.
1990-12-01
The format of this Instrumentation and Controls Division progress report is a major departure from previous reports. This report has been published in two volumes instead of one, and the description of individual activities have been shortened considerably to make it easier document to scan and to read. Volume 1 of this report presents brief descriptions of a few highly significant programmatic and technological efforts representative of Instrumentation and Controls Division activities over the past two years. This volume contains information concerning the publications, presentations, and other professional activities and achievements of I&C Division staff members.
Model based design introduction: modeling game controllers to microprocessor architectures
Jungwirth, Patrick; Badawy, Abdel-Hameed
2017-04-01
We present an introduction to model based design. Model based design is a visual representation, generally a block diagram, to model and incrementally develop a complex system. Model based design is a commonly used design methodology for digital signal processing, control systems, and embedded systems. Model based design's philosophy is: to solve a problem - a step at a time. The approach can be compared to a series of steps to converge to a solution. A block diagram simulation tool allows a design to be simulated with real world measurement data. For example, if an analog control system is being upgraded to a digital control system, the analog sensor input signals can be recorded. The digital control algorithm can be simulated with the real world sensor data. The output from the simulated digital control system can then be compared to the old analog based control system. Model based design can compared to Agile software develop. The Agile software development goal is to develop working software in incremental steps. Progress is measured in completed and tested code units. Progress is measured in model based design by completed and tested blocks. We present a concept for a video game controller and then use model based design to iterate the design towards a working system. We will also describe a model based design effort to develop an OS Friendly Microprocessor Architecture based on the RISC-V.
A two isocenter IMRT technique with a controlled junction dose for long volume targets
Zeng, G G; Heaton, R K; Catton, C N; Chung, P W; O'Sullivan, B; Lau, M; Parent, A; Jaffray, D A
2007-01-01
Most IMRT techniques have been designed to treat targets smaller than the field size of conventional linac accelerators. In order to overcome the field size restrictions in applying IMRT, we developed a two isocenter IMRT technique to treat long volume targets. The technique exploits an extended dose gradient throughout a junction region of 4-6 cm to minimize the impact of field match errors on a junction dose and manipulates the inverse planning and IMRT segments to fill in the dose gradient and achieve dose uniformity. Techniques for abutting both conventional fields with IMRT ('Static + IMRT') and IMRT fields ('IMRT + IMRT') using two separate isocenters have been developed. Five long volume sarcoma cases have been planned in Pinnacle (Philips, Madison, USA) using Elekta Synergy and Varian 2100EX linacs; two of the cases were clinically treated with this technique. Advantages were demonstrated with well-controlled junction target uniformity and tolerance to setup uncertainties. The junction target dose heterogeneity was controlled at a level of ±5%; for 3 mm setup errors at the field edges, the junction target dose changed less than 5% and the dose sparing to organs at risk (OARs) was maintained. Film measurements confirmed the treatment planning results
Wind farm models and control strategies
Soerensen, Poul; Hansen, Anca D.; Iov, F.; Blaabjerg, F.; Donovan, M.H.
2005-08-01
This report describes models and control strategies for 3 different concepts of wind farms. Initially, the potential in improvement of grid integration, structural loads and energy production is investigated in a survey of opportunities. Then simulation models are described, including wind turbine models for a fixed speed wind turbine with active stall control and a variable speed wind turbine with doubly-fed induction generator. After that, the 3 wind farm concepts and control strategies are described. The 3 concepts are AC connected doubly fed turbines, AC connected active stall turbines and DC connected active stall turbines. Finally, some simulation examples and conclusions are presented. (au)
Modelling supervisory controller for hybrid power systems
Pereira, A; Bindner, H; Lundsager, P [Risoe National Lab., Roskilde (Denmark); Jannerup, O [Technical Univ. of Denmark, Dept. of Automation, Lyngby (Denmark)
1999-03-01
Supervisory controllers are important to achieve optimal operation of hybrid power systems. The performance and economics of such systems depend mainly on the control strategy for switching on/off components. The modular concept described in this paper is an attempt to design standard supervisory controllers that could be used in different applications, such as village power and telecommunication applications. This paper presents some basic aspects of modelling and design of modular supervisory controllers using the object-oriented modelling technique. The functional abstraction hierarchy technique is used to formulate the control requirements and identify the functions of the control system. The modular algorithm is generic and flexible enough to be used with any system configuration and several goals (different applications). The modularity includes accepting modification of system configuration and goals during operation with minor or no changes in the supervisory controller. (au)
Contrast Gain Control Model Fits Masking Data
Watson, Andrew B.; Solomon, Joshua A.; Null, Cynthia H. (Technical Monitor)
1994-01-01
We studied the fit of a contrast gain control model to data of Foley (JOSA 1994), consisting of thresholds for a Gabor patch masked by gratings of various orientations, or by compounds of two orientations. Our general model includes models of Foley and Teo & Heeger (IEEE 1994). Our specific model used a bank of Gabor filters with octave bandwidths at 8 orientations. Excitatory and inhibitory nonlinearities were power functions with exponents of 2.4 and 2. Inhibitory pooling was broad in orientation, but narrow in spatial frequency and space. Minkowski pooling used an exponent of 4. All of the data for observer KMF were well fit by the model. We have developed a contrast gain control model that fits masking data. Unlike Foley's, our model accepts images as inputs. Unlike Teo & Heeger's, our model did not require multiple channels for different dynamic ranges.
International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines
Belyaev, Alexander; Krommer, Michael
2017-01-01
The papers in this volume present and discuss the frontiers in the mechanics of controlled machines and structures. They are based on papers presented at the International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines held in Vienna in September 2015. The workshop continues a series of international workshops held in Linz (2008) and St. Petersburg (2010).
Touj, Sara; Houle, Sébastien; Ramla, Djamel; Jeffrey-Gauthier, Renaud; Hotta, Harumi; Bronchti, Gilles; Martinoli, Maria-Grazia; Piché, Mathieu
2017-06-03
Chronic pain is associated with autonomic disturbance. However, specific effects of chronic back pain on sympathetic regulation remain unknown. Chronic pain is also associated with structural changes in the anterior cingulate cortex (ACC), which may be linked to sympathetic dysregulation. The aim of this study was to determine whether sympathetic regulation and ACC surface and volume are affected in a rat model of chronic back pain, in which complete Freund Adjuvant (CFA) is injected in back muscles. Sympathetic regulation was assessed with renal blood flow (RBF) changes induced by electrical stimulation of a hind paw, while ACC structure was examined by measuring cortical surface and volume. RBF changes and ACC volume were compared between control rats and rats injected with CFA in back muscles segmental (T10) to renal sympathetic innervation or not (T2). In rats with CFA, chronic inflammation was observed in the affected muscles in addition to increased nuclear factor-kappa B (NF-kB) protein expression in corresponding spinal cord segments (p=0.01) as well as decreased ACC volume (pchronic pain at T2 (p'schronic back pain alters sympathetic functions through non-segmental mechanisms, possibly by altering descending regulatory pathways from ACC. Yet, segmental somato-sympathetic reflexes may compete with non-segmental processes depending on the back region affected by pain and according to the segmental organization of the sympathetic nervous system. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
Whole object surface area and volume of partial-view 3D models
Mulukutla, Gopal K; Proussevitch, Alexander A; Genareau, Kimberly D; Durant, Adam J
2017-01-01
Micro-scale 3D models, important components of many studies in science and engineering, are often used to determine morphological characteristics such as shape, surface area and volume. The application of techniques such as stereoscopic scanning electron microscopy on whole objects often results in ‘partial-view’ models with a portion of object not within the field of view thus not captured in the 3D model. The nature and extent of the surface not captured is dependent on the complex interaction of imaging system attributes (e.g. working distance, viewing angle) with object size, shape and morphology. As a result, any simplistic assumptions in estimating whole object surface area or volume can lead to significant errors. In this study, we report on a novel technique to estimate the physical fraction of an object captured in a partial-view 3D model of an otherwise whole object. This allows a more accurate estimate of surface area and volume. Using 3D models, we demonstrate the robustness of this method and the accuracy of surface area and volume estimates relative to true values. (paper)
Fusion reactor control study. Volume 3. Tandem mirror reactors. Final report
Chang, F.R.; DeCanio, F.; Fisher, J.L.; Madden, P.A.
1982-03-01
A study of the control requirements of the Tandem Mirror Reactor concept is reported. The study describes the development of a control simulator that is based upon a spatially averaged physics code of the reactor concept. The simulator portrays the evolution of the plasma through the complete reactor operating cycle; it includes models of the control and measurement system, thus allowing the exploration of various strategies for reactor control. Startup, shutdown, and control during the quasi-steady-state power producing phase were explored. Configurations are described which use a variety of control effectors including modulation of the refueling rate, beam current, and electron cyclotron resonance heating. Multivariable design techniques were used to design the control laws and compensators for the feedback controllers and presume the practical measurement of only a subset of the plasma and machine variables. Performance of the various controllers is explored using the nonlinear control simulator. Derivative control strategies using new or developed sensors and effectors appropriate to a power reactor environment are postulated, based upon the results of the control configurations tested. Research and development requirements for these controls are delineated
Connolly, Joseph W.; Kopasakis, George; Lemon, Kimberly A.
2010-01-01
A turbofan simulation has been developed for use in aero-propulso-servo-elastic coupling studies, on supersonic vehicles. A one-dimensional lumped volume approach is used whereby each component (fan, high-pressure compressor, combustor, etc.) is represented as a single volume using characteristic performance maps and conservation equations for continuity, momentum and energy. The simulation is developed in the MATLAB/SIMULINK (The MathWorks, Inc.) environment in order to facilitate controls development, and ease of integration with a future aero-servo-elastic vehicle model being developed at NASA Langley. The complete simulation demonstrated steady state results that closely match a proposed engine suitable for a supersonic business jet at the cruise condition. Preliminary investigation of the transient simulation revealed expected trends for fuel flow disturbances as well as upstream pressure disturbances. A framework for system identification enables development of linear models for controller design. Utilizing this framework, a transfer function modeling an upstream pressure disturbance s impacts on the engine speed is developed as an illustrative case of the system identification. This work will eventually enable an overall vehicle aero-propulso-servo-elastic model
Modelling and control of large cryogenic refrigerator
Bonne, Francois
2014-01-01
This manuscript is concern with both the modeling and the derivation of control schemes for large cryogenic refrigerators. The particular case of those which are submitted to highly variable pulsed heat load is studied. A model of each object that normally compose a large cryo-refrigerator is proposed. The methodology to gather objects model into the model of a subsystem is presented. The manuscript also shows how to obtain a linear equivalent model of the subsystem. Based on the derived models, advances control scheme are proposed. Precisely, a linear quadratic controller for warm compression station working with both two and three pressures state is derived, and a predictive constrained one for the cold-box is obtained. The particularity of those control schemes is that they fit the computing and data storage capabilities of Programmable Logic Controllers (PLC) with are well used in industry. The open loop model prediction capability is assessed using experimental data. Developed control schemes are validated in simulation and experimentally on the 400W1.8K SBT's cryogenic test facility and on the CERN's LHC warm compression station. (author) [fr
Free volume model: High-temperature deformation of a Zr-based bulk metallic glass
Bletry, M.; Guyot, P.; Blandin, J.J.; Soubeyroux, J.L.
2006-01-01
The homogeneous deformation of a zirconium-based bulk metallic glass is investigated in the glass transition region. Compression tests at different temperatures and strain rates have been conducted. The mechanical behavior is analyzed in the framework of the free volume model, taking into account the dependence of the flow defect concentration on deformation. The activation volume is evaluated and allows one to gather the viscosity data (for the different strain rates and temperatures) on a unique master curve. It is also shown that, due to the relation between flow defect concentration and free volume, it is not possible to deduce the equilibrium flow defect concentration directly from mechanical measurements. However, if this parameter is arbitrarily chosen, mechanical measurements give access to the other parameters of the model, these parameters for the alloy under investigation being of the same order of magnitude as those for other metallic glasses
Goret, C.
1990-12-01
Several technics of imaging (IRM, image scanners, tomoscintigraphy, echography) give numerical informations presented by means of a stack of parallel cross-sectional images. Since many years, 3-D mathematical tools have been developed and allow the 3 D images synthesis of surfaces. In first part, we give the technics of numerical volume exploitation and their medical applications to diagnosis and therapy. The second part is about a continuous modelling of the volume with a tensor product of cubic splines. We study the characteristics of this representation and its clinical validation. Finally, we treat of the problem of surface visualization of objects contained in the volume. The results show the interest of this model and allow to propose specifications for 3-D workstation realization [fr
Monbouquette, H G
1987-06-01
Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity.
Models for high cell density bioreactors must consider biomass volume fraction: cell recycle example
Monbouquette, H.G.
1987-06-01
Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity. (Refs. 14).
Glass Property Data and Models for Estimating High-Level Waste Glass Volume
Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang; Hrma, Pavel R.
2009-10-05
This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition models were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.
Glass Property Data and Models for Estimating High-Level Waste Glass Volume
Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang; Hrma, Pavel R.
2009-01-01
This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition models were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.
Aspects of modelling and control of bioprocesses
Zhang, Xiachang
1996-12-31
The modelling and control of bioprocesses are the main subjects in this thesis. Different modelling approaches are proposed for different purposes in various bioprocesses. A conventional global model was constructed for a very complex mammalian cell culture process. A new concept of functional state and a multiple model (local models) approach were used for modelling the fed-batch baker`s yeast process for monitoring and control purposes. Finally, a combination of conventional electrical and biological models was used to simulate and to control a microbial fuel cell process. In the thesis, a yeast growth process was taken as an example to demonstrate the usefulness of the functional state concept and local models. The functional states were first defined according to the yeast metabolism. The process was then described by a set of simple local models. In different functional states, different local models were used. On the other hand, the on-line estimation of functional state and biomass of the process was discussed for process control purpose. As a consequence, both the functional state concept and the multiple model approach were applied for fuzzy logic control of yeast growth process. A fuzzy factor was calculated on the basis of a knowledge-based expert system and fuzzy logic rules. The factor was used to correct an ideal substrate feed rate. In the last part of the thesis, microbial fuel cell processes were studied. A microbial fuel cell is a device for direct conversion of chemical energy to electrical energy by using micro-organisms as catalysts. A combined model including conventional electrical and biological models was constructed for the process based on the biological and electrochemical phenomena
Aspects of modelling and control of bioprocesses
Zhang, Xiachang
1995-12-31
The modelling and control of bioprocesses are the main subjects in this thesis. Different modelling approaches are proposed for different purposes in various bioprocesses. A conventional global model was constructed for a very complex mammalian cell culture process. A new concept of functional state and a multiple model (local models) approach were used for modelling the fed-batch baker`s yeast process for monitoring and control purposes. Finally, a combination of conventional electrical and biological models was used to simulate and to control a microbial fuel cell process. In the thesis, a yeast growth process was taken as an example to demonstrate the usefulness of the functional state concept and local models. The functional states were first defined according to the yeast metabolism. The process was then described by a set of simple local models. In different functional states, different local models were used. On the other hand, the on-line estimation of functional state and biomass of the process was discussed for process control purpose. As a consequence, both the functional state concept and the multiple model approach were applied for fuzzy logic control of yeast growth process. A fuzzy factor was calculated on the basis of a knowledge-based expert system and fuzzy logic rules. The factor was used to correct an ideal substrate feed rate. In the last part of the thesis, microbial fuel cell processes were studied. A microbial fuel cell is a device for direct conversion of chemical energy to electrical energy by using micro-organisms as catalysts. A combined model including conventional electrical and biological models was constructed for the process based on the biological and electrochemical phenomena
MELSAR: a mesoscale air quality model for complex terrain. Volume 2. Appendices
Allwine, K.J.; Whiteman, C.D.
1985-04-01
This final report is submitted as part of the Green River Ambient Model Assessment (GRAMA) project conducted at the US Department of Energy's Pacific Northwest Laboratory for the US Environmental Protection Agency. The GRAMA Program has, as its ultimate goal, the development of validated air quality models that can be applied to the complex terrain of the Green River Formation of western Colorado, eastern Utah and southern Wyoming. The Green River Formation is a geologic formation containing large reserves of oil shale, coal, and other natural resources. Development of these resources may lead to a degradation of the air quality of the region. Air quality models are needed immediately for planning and regulatory purposes to assess the magnitude of these regional impacts. This report documents one of the models being developed for this purpose within GRAMA - specifically a model to predict short averaging time (less than or equal to 24 h) pollutant concentrations resulting from the mesoscale transport of pollutant releases from multiple sources. MELSAR has not undergone any rigorous operational testing, sensitivity analyses, or validation studies. Testing and evaluation of the model are needed to gain a measure of confidence in the model's performance. This report consists of two volumes. This volume contains the Appendices, which include listings of the FORTRAN code and Volume 1 contains the model overview, technical description, and user's guide. 13 figs., 10 tabs.
METHODOLOGY OF THE DRUGS MARKET VOLUME MODELING ON THE EXAMPLE OF HEMOPHILIA A
N. B. Molchanova
2015-01-01
Full Text Available Hemophilia A is a serious genetic disease, which may lead to disability of a patient even in early ages without a required therapy. The only one therapeutic approach is a replacement therapy with drugs of bloodcoagulation factor VIII (FVIII. The modeling of coagulation drugs market volume will allow evaluation of the level of patients’ provision with a necessary therapy. Modeling of a “perfect” market of drugs and its comparison with the real one was the purpose of the study. During the modeling of market volume we have used the data about the number of hamophilia A patients on the basis of the federal registry, Russian and international morbidity indices, and the data of a real practice about average consumption of drugs of bloodcoagulation factors and data about the drugs prescription according to the standards and protocols of assistance rendering. According to the standards of care delivery, average annual volume of FVIII drugs consumption amounted to 406 325 244 IU for children and 964 578 678 IU for adults, i.e. an average volume of a “perfect” market is equal to 1 370 903 922 IU for all patients. The market volume is 1.8 times bigger than a real volume of FVIII drugs which, according to the data of IMS marketing agency, amounted to 765 000 000 IU in 2013. The modeling conducted has shown that despite a relatively high patients’ coverage there is a potential for almost double growth.
Mob control models of threshold collective behavior
Breer, Vladimir V; Rogatkin, Andrey D
2017-01-01
This book presents mathematical models of mob control with threshold (conformity) collective decision-making of the agents. Based on the results of analysis of the interconnection between the micro- and macromodels of active network structures, it considers the static (deterministic, stochastic and game-theoretic) and dynamic (discrete- and continuous-time) models of mob control, and highlights models of informational confrontation. Many of the results are applicable not only to mob control problems, but also to control problems arising in social groups, online social networks, etc. Aimed at researchers and practitioners, it is also a valuable resource for undergraduate and postgraduate students as well as doctoral candidates specializing in the field of collective behavior modeling.
A model to incorporate organ deformation in the evaluation of dose/volume relationship
Yan, D.; Jaffray, D.; Wong, J.; Brabbins, D.; Martinez, A. A.
1997-01-01
Purpose: Measurements of internal organ motion have demonstrated that daily organ deformation exists during the course of radiation treatment. However, a model to evaluate the resultant dose delivered to a daily deformed organ remains a difficult challenge. Current methods which model such organ deformation as rigid body motion in the dose calculation for treatment planning evaluation are incorrect and misleading. In this study, a new model for treatment planning evaluation is introduced which incorporates patient specific information of daily organ deformation and setup variation. The model was also used to retrospectively analyze the actual treatment data measured using daily CT scans for 5 patients with prostate treatment. Methods and Materials: The model assumes that for each patient, the organ of interest can be measured during the first few treatment days. First, the volume of each organ is delineated from each of the daily measurements and cumulated in a 3D bit-map. A tissue occupancy distribution is then constructed with the 50% isodensity representing the mean, or effective, organ volume. During the course of treatment, each voxel in the effective organ volume is assumed to move inside a local 3D neighborhood with a specific distribution function. The neighborhood and the distribution function are deduced from the positions and shapes of the organ in the first few measurements using the biomechanics model of viscoelastic body. For each voxel, the local distribution function is then convolved with the spatial dose distribution. The latter includes also the variation in dose due to daily setup error. As a result, the cumulative dose to the voxel incorporates the effects of daily setup variation and organ deformation. A ''variation adjusted'' dose volume histogram, aDVH, for the effective organ volume can then be constructed for the purpose of treatment evaluation and optimization. Up to 20 daily CT scans and daily portal images for 5 patients with prostate
Dong Sup Lee
2011-04-01
Full Text Available Although real-time monitoring of bladder volume together with intravesical pressure can provide more information for understanding the functional changes of the urinary bladder, it still entails difficulties in the accurate prediction of real-time bladder volume in urodynamic studies with small animal models. We studied a new implantable bladder volume monitoring device with eight rats. During cystometry, microelectrodes prepared by the microelectromechanical systems process were placed symmetrically on both lateral walls of the bladder, and the expanded bladder volume was calculated. Immunohistological study was done after 1 week and after 4 weeks to evaluate the biocompatibility of the microelectrode. From the point that infused saline volume into the bladder was higher than 0.6 mL, estimated bladder volume was statistically correlated with the volume of saline injected (p<0.01. Additionally, the microelectromechanical system microelectrodes used in this study showed reliable biocompatibility. Therefore, the device can be used to evaluate changes in bladder volume in studies with small animals, and it may help to provide more information about functional changes in the bladder in laboratory studies. Furthermore, owing to its biocompatibility, the device could be chronically implanted in conscious ambulating animals, thus allowing a novel longitudinal study to be performed for a specific purpose.
Qinghua Xie
2017-01-01
Full Text Available Recently, a general polarimetric model-based decomposition framework was proposed by Chen et al., which addresses several well-known limitations in previous decomposition methods and implements a simultaneous full-parameter inversion by using complete polarimetric information. However, it only employs four typical models to characterize the volume scattering component, which limits the parameter inversion performance. To overcome this issue, this paper presents two general polarimetric model-based decomposition methods by incorporating the generalized volume scattering model (GVSM or simplified adaptive volume scattering model, (SAVSM proposed by Antropov et al. and Huang et al., respectively, into the general decomposition framework proposed by Chen et al. By doing so, the final volume coherency matrix structure is selected from a wide range of volume scattering models within a continuous interval according to the data itself without adding unknowns. Moreover, the new approaches rely on one nonlinear optimization stage instead of four as in the previous method proposed by Chen et al. In addition, the parameter inversion procedure adopts the modified algorithm proposed by Xie et al. which leads to higher accuracy and more physically reliable output parameters. A number of Monte Carlo simulations of polarimetric synthetic aperture radar (PolSAR data are carried out and show that the proposed method with GVSM yields an overall improvement in the final accuracy of estimated parameters and outperforms both the version using SAVSM and the original approach. In addition, C-band Radarsat-2 and L-band AIRSAR fully polarimetric images over the San Francisco region are also used for testing purposes. A detailed comparison and analysis of decomposition results over different land-cover types are conducted. According to this study, the use of general decomposition models leads to a more accurate quantitative retrieval of target parameters. However, there
Sensitivity Analysis of Wavelet Neural Network Model for Short-Term Traffic Volume Prediction
Jinxing Shen
2013-01-01
Full Text Available In order to achieve a more accurate and robust traffic volume prediction model, the sensitivity of wavelet neural network model (WNNM is analyzed in this study. Based on real loop detector data which is provided by traffic police detachment of Maanshan, WNNM is discussed with different numbers of input neurons, different number of hidden neurons, and traffic volume for different time intervals. The test results show that the performance of WNNM depends heavily on network parameters and time interval of traffic volume. In addition, the WNNM with 4 input neurons and 6 hidden neurons is the optimal predictor with more accuracy, stability, and adaptability. At the same time, a much better prediction record will be achieved with the time interval of traffic volume are 15 minutes. In addition, the optimized WNNM is compared with the widely used back-propagation neural network (BPNN. The comparison results indicated that WNNM produce much lower values of MAE, MAPE, and VAPE than BPNN, which proves that WNNM performs better on short-term traffic volume prediction.
OPTIMUM VOLUME OF BANK RESERVE: FORECASTING OF OVERDUE CREDIT INDEBTEDNESS USING COPULA MODELS
Kazakova K. A.
2015-12-01
Full Text Available The article propose to consider the possibility of RLUF-copulas application for the creation of joint distributions of overdue credit indebtedness ranks with macroeconomic indicators for the purpose of indebtedness forecasting and also for the definition of optimum volumes of reserve requirements for the corresponding losses. In this research the comparative analysis of multivariate distributions of RLUF-copula estimation with such classical copulas, as FGM-copula, Frank's copula and Gauss's copula is made. In the article the method of maximum likelihood is used for receiving estimates of model parameters. In case of RLUF-copula Bayesian estimates of parameters are received using the Metropolis algorithm with random volatility. Forecasting of bank reserve volumes for all received models is executed in the form of random sample generation by the means of the algorithm of acceptance-deviation for the creation of the corresponding sample of joint distribution using the copula density function. As the result of playing of hundred possible scenarios of indebtedness volumes is obtained the 95 % confidence level for the possible volume of credit indebtedness which can fully act as the optimum volume of reserve requirements for the corresponding credit losses.
Modelling and control of a flotation process
Ding, L.; Gustafsson, T.
1999-01-01
A general description of a flotation process is given. The dynamic model of a MIMO nonlinear subprocess in flotation, i. e. the pulp levels in five compartments in series is developed and the model is verified with real data from a production plant. In order to reject constant disturbances five extra states are introduced and the model is modified. An exact linearization has been made for the non-linear model and a linear quadratic gaussian controller is proposed based on the linearized model. The simulation result shows an improved performance of the pulp level control when the set points are changed or a disturbance occur. In future the controller will be tested in production. (author)
Control-oriented reduced order modeling of dipteran flapping flight
Faruque, Imraan
Flying insects achieve flight stabilization and control in a manner that requires only small, specialized neural structures to perform the essential components of sensing and feedback, achieving unparalleled levels of robust aerobatic flight on limited computational resources. An engineering mechanism to replicate these control strategies could provide a dramatic increase in the mobility of small scale aerial robotics, but a formal investigation has not yet yielded tools that both quantitatively and intuitively explain flapping wing flight as an "input-output" relationship. This work uses experimental and simulated measurements of insect flight to create reduced order flight dynamics models. The framework presented here creates models that are relevant for the study of control properties. The work begins with automated measurement of insect wing motions in free flight, which are then used to calculate flight forces via an empirically-derived aerodynamics model. When paired with rigid body dynamics and experimentally measured state feedback, both the bare airframe and closed loop systems may be analyzed using frequency domain system identification. Flight dynamics models describing maneuvering about hover and cruise conditions are presented for example fruit flies (Drosophila melanogaster) and blowflies (Calliphorids). The results show that biologically measured feedback paths are appropriate for flight stabilization and sexual dimorphism is only a minor factor in flight dynamics. A method of ranking kinematic control inputs to maximize maneuverability is also presented, showing that the volume of reachable configurations in state space can be dramatically increased due to appropriate choice of kinematic inputs.
Mosaic model for sensorimotor learning and control.
Haruno, M; Wolpert, D M; Kawato, M
2001-10-01
Humans demonstrate a remarkable ability to generate accurate and appropriate motor behavior under many different and often uncertain environmental conditions. We previously proposed a new modular architecture, the modular selection and identification for control (MOSAIC) model, for motor learning and control based on multiple pairs of forward (predictor) and inverse (controller) models. The architecture simultaneously learns the multiple inverse models necessary for control as well as how to select the set of inverse models appropriate for a given environment. It combines both feedforward and feedback sensorimotor information so that the controllers can be selected both prior to movement and subsequently during movement. This article extends and evaluates the MOSAIC architecture in the following respects. The learning in the architecture was implemented by both the original gradient-descent method and the expectation-maximization (EM) algorithm. Unlike gradient descent, the newly derived EM algorithm is robust to the initial starting conditions and learning parameters. Second, simulations of an object manipulation task prove that the architecture can learn to manipulate multiple objects and switch between them appropriately. Moreover, after learning, the model shows generalization to novel objects whose dynamics lie within the polyhedra of already learned dynamics. Finally, when each of the dynamics is associated with a particular object shape, the model is able to select the appropriate controller before movement execution. When presented with a novel shape-dynamic pairing, inappropriate activation of modules is observed followed by on-line correction.
Modelling dynamic liquid-gas systems: Extensions to the volume-of-fluid solver
Heyns, Johan A
2013-06-01
Full Text Available This study presents the extension of the volume-of-fluid solver, interFoam, for improved accuracy and efficiency when modelling dynamic liquid-gas systems. Examples of these include the transportation of liquids, such as in the case of fuel carried...
Grafted polymers with annealed excluded volume : a model for surfactant association in brushes
Currie, E.P.K.; Fleer, G.J.; Cohen Stuart, M.A.; Borisov, O.V.
2000-01-01
We present an analytical self-consistent-field (SCF) theory for a neutral polymer brush (a layer of long polymer chains end-grafted to a surface) with annealed excluded volume interactions between the monomer units. This model mimics the reversible adsorption of solute molecules or aggregates, such
Modeling and (adaptive) control of greenhouse climates
Udink ten Cate, A.J.
1983-01-01
The material presented in this thesis can be grouped around four themes, system concepts, modeling, control and adaptive control. In this summary these themes will be treated separately.
System concepts
In Chapters 1 and 2 an overview of the problem formulation
Controller Synthesis using Qualitative Models and Constraints
Ramamoorthy, Subramanian; Kuipers, Benjamin J
2004-01-01
Many engineering systems require the synthesis of global behaviors in nonlinear dynamical systems. Multiple model approaches to control design make it possible to synthesize robust and optimal versions of such global behaviors. We propose a methodology called Qualitative Heterogeneous Control that enables this type of control design. This methodology is based on a separation of concerns between qualitative correctness and quantitative optimization. Qualitative sufficient conditions are derive...
Simplified ejector model for control and optimization
Zhu Yinhai; Cai Wenjian; Wen Changyun; Li Yanzhong
2008-01-01
In this paper, a simple yet effective ejector model for a real time control and optimization of an ejector system is proposed. Firstly, a fundamental model for calculation of ejector entrainment ratio at critical working conditions is derived by one-dimensional analysis and the shock circle model. Then, based on thermodynamic principles and the lumped parameter method, the fundamental ejector model is simplified to result in a hybrid ejector model. The model is very simple, which only requires two or three parameters and measurement of two variables to determine the ejector performance. Furthermore, the procedures for on line identification of the model parameters using linear and non-linear least squares methods are also presented. Compared with existing ejector models, the solution of the proposed model is much easier without coupled equations and iterative computations. Finally, the effectiveness of the proposed model is validated by published experimental data. Results show that the model is accurate and robust and gives a better match to the real performances of ejectors over the entire operating range than the existing models. This model is expected to have wide applications in real time control and optimization of ejector systems
Volume and Aboveground Biomass Models for Dry Miombo Woodland in Tanzania
Ezekiel Edward Mwakalukwa
2014-01-01
Full Text Available Tools to accurately estimate tree volume and biomass are scarce for most forest types in East Africa, including Tanzania. Based on a sample of 142 trees and 57 shrubs from a 6,065 ha area of dry miombo woodland in Iringa rural district in Tanzania, regression models were developed for volume and biomass of three important species, Brachystegia spiciformis Benth. (n = 40, Combretum molle G. Don (n = 41, and Dalbergia arbutifolia Baker (n = 37 separately, and for broader samples of trees (28 species, n = 72, shrubs (16 species, n = 32, and trees and shrubs combined (44 species, n = 104. Applied independent variables were log-transformed diameter, height, and wood basic density, and in each case a range of different models were tested. The general tendency among the final models is that the fit improved when height and wood basic density were included. Also the precision and accuracy of the predictions tended to increase from general to species-specific models. Except for a few volume and biomass models developed for shrubs, all models had R2 values of 96–99%. Thus, the models appear robust and should be applicable to forests with similar site conditions, species, and diameter ranges.
Yock, Adam D; Rao, Arvind; Dong, Lei; Beadle, Beth M; Garden, Adam S; Kudchadker, Rajat J; Court, Laurence E
2014-05-01
The purpose of this work was to develop and evaluate the accuracy of several predictive models of variation in tumor volume throughout the course of radiation therapy. Nineteen patients with oropharyngeal cancers were imaged daily with CT-on-rails for image-guided alignment per an institutional protocol. The daily volumes of 35 tumors in these 19 patients were determined and used to generate (1) a linear model in which tumor volume changed at a constant rate, (2) a general linear model that utilized the power fit relationship between the daily and initial tumor volumes, and (3) a functional general linear model that identified and exploited the primary modes of variation between time series describing the changing tumor volumes. Primary and nodal tumor volumes were examined separately. The accuracy of these models in predicting daily tumor volumes were compared with those of static and linear reference models using leave-one-out cross-validation. In predicting the daily volume of primary tumors, the general linear model and the functional general linear model were more accurate than the static reference model by 9.9% (range: -11.6%-23.8%) and 14.6% (range: -7.3%-27.5%), respectively, and were more accurate than the linear reference model by 14.2% (range: -6.8%-40.3%) and 13.1% (range: -1.5%-52.5%), respectively. In predicting the daily volume of nodal tumors, only the 14.4% (range: -11.1%-20.5%) improvement in accuracy of the functional general linear model compared to the static reference model was statistically significant. A general linear model and a functional general linear model trained on data from a small population of patients can predict the primary tumor volume throughout the course of radiation therapy with greater accuracy than standard reference models. These more accurate models may increase the prognostic value of information about the tumor garnered from pretreatment computed tomography images and facilitate improved treatment management.
Multiple model adaptive control with mixing
Kuipers, Matthew
Despite the remarkable theoretical accomplishments and successful applications of adaptive control, the field is not sufficiently mature to solve challenging control problems requiring strict performance and safety guarantees. Towards addressing these issues, a novel deterministic multiple-model adaptive control approach called adaptive mixing control is proposed. In this approach, adaptation comes from a high-level system called the supervisor that mixes into feedback a number of candidate controllers, each finely-tuned to a subset of the parameter space. The mixing signal, the supervisor's output, is generated by estimating the unknown parameters and, at every instant of time, calculating the contribution level of each candidate controller based on certainty equivalence. The proposed architecture provides two characteristics relevant to solving stringent, performance-driven applications. First, the full-suite of linear time invariant control tools is available. A disadvantage of conventional adaptive control is its restriction to utilizing only those control laws whose solutions can be feasibly computed in real-time, such as model reference and pole-placement type controllers. Because its candidate controllers are computed off line, the proposed approach suffers no such restriction. Second, the supervisor's output is smooth and does not necessarily depend on explicit a priori knowledge of the disturbance model. These characteristics can lead to improved performance by avoiding the unnecessary switching and chattering behaviors associated with some other multiple adaptive control approaches. The stability and robustness properties of the adaptive scheme are analyzed. It is shown that the mean-square regulation error is of the order of the modeling error. And when the parameter estimate converges to its true value, which is guaranteed if a persistence of excitation condition is satisfied, the adaptive closed-loop system converges exponentially fast to a closed
1982-01-01
This report presents a preliminary overview of potential applications for robotics and remote control in the Canadian mining industry. The first of two volumes, summarizes the industry awareness and interest in using these technologies. Also included is a look at factors playing a major role in the development of the mining robotics industry, such as safety, productivity, labour and the economic climate. The role of Energy, Mines and Resources Canada (EMR)/CANMET is also discussed. Finally, recommendations are made as to how Canada, through EMR, can ensure Canada's participation in the development of robotics in the mining industry. Volume two is comprised of the contact records. These are abbreviated notes of conversations which took place between the interviewers and their contacts in a number of Canadian and US mines and associated government and private agencies. (The interviews represent the opinions of the respondents, not necessarily that of their companies). The survey indicated that the industry is essentially negative to the idea of robotics in mining, but they were able to suggest many potential areas of application, especially at the short term level.
Ezequiel Gasparin
2015-10-01
Full Text Available Growing demand for native tree seedlings will require improvements in quality standards of production processes through the use of more efficient cultivation techniques. This study evaluated the effects of different doses of controlled release fertilizer (CRF and different container volumes in the production of Parapiptadenia rigida seedlings. We examined the effects of five different concentrations (0, 3, 6, 9 and 12 g L-1 substrate of CRF (18-5-9 NPK and three different container volumes (50, 110 and 180 cm3 on seedling height (H and collar diameter (CD measured monthly for seven months and then calculated H/CD ratios. After 210 days of growth, the dry masses of the aerial portions, root systems, and total masses were determined, as well as the concentrations of macro- and micronutrients in the aerial portions of the seedlings. In general, the dose 9 g L-1 substrate combined with the 180 cm3 cultivation tubes demonstrated the best results in terms of the morphological variables analyzed, resulting in consistent quality seedlings for field planting.
Modelling and control of refrigerant circuits
Gruhle, W D; Isermann, R
1987-01-01
Conventional evaporator control systems involving a thermostatic expansion valve often to not work satisfactorily in terms of stability and evaporator utilization. To improve this, the author first studies the cause of this behaviour by means of theoretic modelling which is greatly determined by processes occurring within the evaporator and by structural combinations. After verification of the simulated model by means of measurements performed on a pilot plant, the results obtained are used to build up a new control system. Various experiments reveal a clearly improved evaporator utilization at greater control stability. (orig.).
An enhanced finite volume method to model 2D linear elastic structures
Suliman, Ridhwaan
2014-04-01
Full Text Available . Suliman) Preprint submitted to Applied Mathematical Modelling July 22, 2013 Keywords: finite volume, finite element, locking, error analysis 1. Introduction Since the 1960s, the finite element method has mainly been used for modelling the mechanics... formulation provides higher accuracy 2 for displacement solutions. It is well known that the linear finite element formulation suffers from sensitivity to element aspect ratio or shear locking when subjected to bend- ing [16]. Fallah [8] and Wheel [6] present...
Volume simplicity constraint in the Engle-Livine-Pereira-Rovelli spin foam model
Bahr, Benjamin; Belov, Vadim
2018-04-01
We propose a quantum version of the quadratic volume simplicity constraint for the Engle-Livine-Pereira-Rovelli spin foam model. It relies on a formula for the volume of 4-dimensional polyhedra, depending on its bivectors and the knotting class of its boundary graph. While this leads to no further condition for the 4-simplex, the constraint becomes nontrivial for more complicated boundary graphs. We show that, in the semiclassical limit of the hypercuboidal graph, the constraint turns into the geometricity condition observed recently by several authors.
Kamson, David O; Juhász, Csaba; Chugani, Harry T; Jeong, Jeong-Won
2015-04-01
Diffusion tensor imaging (DTI) has expanded our knowledge of corticospinal tract (CST) anatomy and development. However, previous developmental DTI studies assessed the CST as a whole, overlooking potential differences in development of its components related to control of the upper and lower extremities. The present cross-sectional study investigated age-related changes, side and gender differences in streamline volume of the leg- and hand-related segments of the CST in children. DTI data of 31 children (1-14 years; mean age: 6±4 years; 17 girls) with normal conventional MRI were analyzed. Leg- and hand-related CST streamline volumes were quantified separately, using a recently validated novel tractography approach. CST streamline volumes on both sides were compared between genders and correlated with age. Higher absolute streamline volumes were found in the left leg-related CST compared to the right (p=0.001) without a gender effect (p=0.4), whereas no differences were found in the absolute hand-related CST volumes (p>0.4). CST leg-related streamline volumes, normalized to hemispheric white matter volumes, declined with age in the right hemisphere only (R=-.51; p=0.004). Absolute leg-related CST streamline volumes showed similar, but slightly weaker correlations. Hand-related absolute or normalized CST streamline volumes showed no age-related variations on either side. These results suggest differential development of CST segments controlling hand vs. leg movements. Asymmetric volume changes in the lower limb motor pathway may be secondary to gradually strengthening left hemispheric dominance and is consistent with previous data suggesting that footedness is a better predictor of hemispheric lateralization than handedness. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Model Based Control of Refrigeration Systems
Larsen, Lars Finn Sloth
for automation of these procedures, that is to incorporate some "intelligence" in the control system, this project was started up. The main emphasis of this work has been on model based methods for system optimizing control in supermarket refrigeration systems. The idea of implementing a system optimizing...... control is to let an optimization procedure take over the task of operating the refrigeration system and thereby replace the role of the operator in the traditional control structure. In the context of refrigeration systems, the idea is to divide the optimizing control structure into two parts: A part...... optimizing the steady state operation "set-point optimizing control" and a part optimizing dynamic behaviour of the system "dynamical optimizing control". A novel approach for set-point optimization will be presented. The general idea is to use a prediction of the steady state, for computation of the cost...
Distributed model predictive control made easy
Negenborn, Rudy
2014-01-01
The rapid evolution of computer science, communication, and information technology has enabled the application of control techniques to systems beyond the possibilities of control theory just a decade ago. Critical infrastructures such as electricity, water, traffic and intermodal transport networks are now in the scope of control engineers. The sheer size of such large-scale systems requires the adoption of advanced distributed control approaches. Distributed model predictive control (MPC) is one of the promising control methodologies for control of such systems. This book provides a state-of-the-art overview of distributed MPC approaches, while at the same time making clear directions of research that deserve more attention. The core and rationale of 35 approaches are carefully explained. Moreover, detailed step-by-step algorithmic descriptions of each approach are provided. These features make the book a comprehensive guide both for those seeking an introduction to distributed MPC as well as for those ...
Merchant, Thomas E., E-mail: thomas.merchant@stjude.org [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Kun, Larry E.; Hua, Chia-Ho [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Wu, Shengjie; Xiong, Xiaoping [St Jude Children' s Research Hospital, Biostatistics, Memphis, Tennessee (United States); Sanford, Robert A.; Boop, Frederick A. [Semmes Murphey Neurologic and Spine Institute, Neurosurgery, Memphis, Tennessee (United States)
2013-03-15
Purpose: To estimate the rate of disease control after conformal radiation therapy using reduced clinical target volume (CTV) margins and to determine factors that predict for tumor progression. Methods and Materials: Eighty-eight children (median age, 8.5 years; range, 3.2-17.6 years) received conformal or intensity modulated radiation therapy between 1998 and 2009. The study group included those prospectively treated from 1998 to 2003, using a 10-mm CTV, defined as the margin surrounding the solid and cystic tumor targeted to receive the prescription dose of 54 Gy. The CTV margin was subsequently reduced after 2003, yielding 2 groups of patients: those treated with a CTV margin greater than 5 mm (n=26) and those treated with a CTV margin less than or equal to 5 mm (n=62). Disease progression was estimated on the basis of additional variables including sex, race, extent of resection, tumor interventions, target volume margins, and frequency of weekly surveillance magnetic resonance (MR) imaging during radiation therapy. Median follow-up was 5 years. Results: There was no difference between progression-free survival rates based on CTV margins (>5 mm vs ≤5 mm) at 5 years (88.1% ± 6.3% vs 96.2% ± 4.4% [P=.6386]). There were no differences based on planning target volume (PTV) margins (or combined CTV plus PTV margins). The PTV was systematically reduced from 5 to 3 mm during the time period of the study. Factors predictive of superior progression-free survival included Caucasian race (P=.0175), no requirement for cerebrospinal fluid shunting (P=.0066), and number of surveillance imaging studies during treatment (P=.0216). Patients whose treatment protocol included a higher number of weekly surveillance MR imaging evaluations had a lower rate of tumor progression. Conclusions: These results suggest that targeted volume reductions for radiation therapy using smaller margins are feasible and safe but require careful monitoring. We are currently investigating
Intelligent Mechatronic Systems Modeling, Control and Diagnosis
Merzouki, Rochdi; Pathak, Pushparaj Mani; Ould Bouamama, Belkacem
2013-01-01
Acting as a support resource for practitioners and professionals looking to advance their understanding of complex mechatronic systems, Intelligent Mechatronic Systems explains their design and recent developments from first principles to practical applications. Detailed descriptions of the mathematical models of complex mechatronic systems, developed from fundamental physical relationships, are built on to develop innovative solutions with particular emphasis on physical model-based control strategies. Following a concurrent engineering approach, supported by industrial case studies, and drawing on the practical experience of the authors, Intelligent Mechatronic Systems covers range of topic and includes: • An explanation of a common graphical tool for integrated design and its uses from modeling and simulation to the control synthesis • Introductions to key concepts such as different means of achieving fault tolerance, robust overwhelming control and force and impedance control • Dedicated chapters ...
NONLINEAR MODEL PREDICTIVE CONTROL OF CHEMICAL PROCESSES
SILVA R. G.
1999-01-01
Full Text Available A new algorithm for model predictive control is presented. The algorithm utilizes a simultaneous solution and optimization strategy to solve the model's differential equations. The equations are discretized by equidistant collocation, and along with the algebraic model equations are included as constraints in a nonlinear programming (NLP problem. This algorithm is compared with the algorithm that uses orthogonal collocation on finite elements. The equidistant collocation algorithm results in simpler equations, providing a decrease in computation time for the control moves. Simulation results are presented and show a satisfactory performance of this algorithm.
The Development of a Finite Volume Method for Modeling Sound in Coastal Ocean Environment
Long, Wen; Yang, Zhaoqing; Copping, Andrea E.; Jung, Ki Won; Deng, Zhiqun
2015-10-28
: As the rapid growth of marine renewable energy and off-shore wind energy, there have been concerns that the noises generated from construction and operation of the devices may interfere marine animals’ communication. In this research, a underwater sound model is developed to simulate sound prorogation generated by marine-hydrokinetic energy (MHK) devices or offshore wind (OSW) energy platforms. Finite volume and finite difference methods are developed to solve the 3D Helmholtz equation of sound propagation in the coastal environment. For finite volume method, the grid system consists of triangular grids in horizontal plane and sigma-layers in vertical dimension. A 3D sparse matrix solver with complex coefficients is formed for solving the resulting acoustic pressure field. The Complex Shifted Laplacian Preconditioner (CSLP) method is applied to efficiently solve the matrix system iteratively with MPI parallelization using a high performance cluster. The sound model is then coupled with the Finite Volume Community Ocean Model (FVCOM) for simulating sound propagation generated by human activities in a range-dependent setting, such as offshore wind energy platform constructions and tidal stream turbines. As a proof of concept, initial validation of the finite difference solver is presented for two coastal wedge problems. Validation of finite volume method will be reported separately.
Newkirk, H.W.
1976-01-01
Volume I deals with sources (what the emissions are and where they come from), trends (quantities of emissions and their dispersion with time), and costs of control (what it takes in time, energy, and money to meet minimum standards). Volume II concerns itself with the public health effects of energy production and utilization. Volume III summarizes the various techniques for controlling emissions, technological as well as economic, social, and political. Each volume is divided into sections dealing with the atmosphere, water, land, and social activities--each division indicating a particular sphere of man's environment affected by energy production and use. The sources of information that were used in this study included textbooks, journal articles, technical reports, memoranda, letters, and personal communications. These are cited in the text at the end of each subsection and on the applicable tables and figures
Newkirk, H.W. (comp.)
1976-05-01
Volume I deals with sources (what the emissions are and where they come from), trends (quantities of emissions and their dispersion with time), and costs of control (what it takes in time, energy, and money to meet minimum standards). Volume II concerns itself with the public health effects of energy production and utilization. Volume III summarizes the various techniques for controlling emissions, technological as well as economic, social, and political. (For abstracts of Vols. II and III, see ERDA Energy Research Abstracts, Vol. 2, Absts. 5764 and 5670, respectively) Each volume is divided into sections dealing with the atmosphere, water, land, and social activities--each division indicating a particular sphere of man's environment affected by energy production and use. The sources of information that were used in this study included textbooks, journal articles, technical reports, memoranda, letters, and personal communications. These are cited in the text at the end of each subsection and on the applicable tables and figures.
Chen Qiang
2016-01-01
Full Text Available Equipment Failure Root Cause Analysis (ERCA methodology is employed in this paper to investigate the root cause for charging pump’s pressure fluctuation of chemical and volume control system (RCV in pressurized water reactor (PWR nuclear power plant. RCA project task group has been set up at the beginning of the analysis process. The possible failure modes are listed according to the characteristics of charging pump’s actual pressure fluctuation and maintenance experience during the analysis process. And the failure modes are analysed in proper sequence by the evidence-collecting. It suggests that the gradually untightened and loosed shaft nut in service should be the root cause. And corresponding corrective actions are put forward in details.
Two stage neural network modelling for robust model predictive control.
Patan, Krzysztof
2018-01-01
The paper proposes a novel robust model predictive control scheme realized by means of artificial neural networks. The neural networks are used twofold: to design the so-called fundamental model of a plant and to catch uncertainty associated with the plant model. In order to simplify the optimization process carried out within the framework of predictive control an instantaneous linearization is applied which renders it possible to define the optimization problem in the form of constrained quadratic programming. Stability of the proposed control system is also investigated by showing that a cost function is monotonically decreasing with respect to time. Derived robust model predictive control is tested and validated on the example of a pneumatic servomechanism working at different operating regimes. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
Extension of the direct statistical approach to a volume parameter model (non-integer splitting)
Burn, K.W.
1990-01-01
The Direct Statistical Approach is a rigorous mathematical derivation of the second moment for surface splitting and Russian Roulette games attached to the Monte Carlo modelling of fixed source particle transport. It has been extended to a volume parameter model (involving non-integer ''expected value'' splitting), and then to a cell model. The cell model gives second moment and time functions that have a closed form. This suggests the possibility of two different methods of solution of the optimum splitting/Russian Roulette parameters. (author)
Choi, Hee Seok; Kim, Kwang Ki; Yoon, Yup Yoon [Dongguk University Medical Center, Goyang (Korea, Republic of); Seo, Hyung Suk [Korea University Ansan Hospital, Ansan (Korea, Republic of)
2009-07-15
To compare the corpus callosum (CC) area and brain volume among individuals with Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls (HC). To evaluate the relationship of CC area and brain volume in 111 subjects (M:F = 48:63; mean age, 56.9 years) without memory disturbance and 28 subjects (11:17; 66.7years) with memory disturbance. The 11 AD (3:8; 75.7 years), 17 MCI (8:9; 60.9 years) and 28 selected HC (11:17; 66.4 years) patients were investigated for comparison of their CC area and brain volume. A good positive linear correlation was found between CC area and brain volume in subjects without and with memory disturbance (r = 0.64 and 0.66, respectively, p < 0.01). The CC area and brain volume in AD patients (498.7 +- 72 mm{sup 2}, 715.4 +- 107 cm3) were significantly smaller than in MCI patients (595.9 +- 108, 844.1 +- 85) and the HCs (563.2 +- 75, 818.9 +- 109) (p < 0.05). The CC area and brain volume were not significantly different between MCI patients and the HCs. The CC area was significantly correlated with brain volume. Both CC area and brain volume were significantly smaller in the AD patients
Volume Threshold for Chest Tube Removal: A Randomized Controlled Trial
Sajad Hatami
2009-07-01
Full Text Available Background: Despite importance of chest tube insertion in chest trauma, there is no general agreement on the level of daily volume drainage from chest tube. This study was conducted to compare the effectiveness and safety of chest tube removal at the levels of 150 ml/day and 2oo ml/day. Methods: Eligible patients (138 who needed replacement of chest tube (because of trauma or malignancy were randomized into two groups; control (removal of chest tube when drainage reached to 150 ml/day and trial (removal of chest tube at the level of 200 ml/day. All patients received standard care during hospital admission and a follow-up visit after 7days of discharge from hospital. Patients were then compared in terms of major clinical outcomes using chi-squared and t-test. Results: From the total of 138 patients, 70 and 68 patients were randomized to control (G150 and trial (G200 group, respectively. Baseline characteristics were comparable between the two groups. Although the trial group had a shorter mean for length of hospital stay (LOS (4.1 compared to 4.8, p=0.04, their differences in drainage time did not reach to the level of statistical significance (p=0.1. Analysis of data showed no statistically significant differences between the rate of radiological reaccumulation, thoracentesis and decrease in pulmonary sounds (auscultatory, one week after discharge from hospital. Conclusions: Compared to a daily volume drainage of 150 ml, removal of chest tube when there is 200 ml/day is safe and will even result in a shorter hospital stay. This in turn leads to a lower cost.
Kereszturi, Gábor; Németh, Károly; Cronin, Shane J.; Agustín-Flores, Javier; Smith, Ian E. M.; Lindsay, Jan
2013-10-01
Monogenetic basaltic volcanism is characterised by a complex array of behaviours in the spatial distribution of magma output and also temporal variability in magma flux and eruptive frequency. Investigating this in detail is hindered by the difficulty in evaluating ages of volcanic events as well as volumes erupted in each volcano. Eruptive volumes are an important input parameter for volcanic hazard assessment and may control eruptive scenarios, especially transitions between explosive and effusive behaviour and the length of eruptions. Erosion, superposition and lack of exposure limit the accuracy of volume determination, even for very young volcanoes. In this study, a systematic volume estimation model is developed and applied to the Auckland Volcanic Field in New Zealand. In this model, a basaltic monogenetic volcano is categorised in six parts. Subsurface portions of volcanoes, such as diatremes beneath phreatomagmatic volcanoes, or crater infills, are approximated by geometrical considerations, based on exposed analogue volcanoes. Positive volcanic landforms, such as scoria/spatter cones, tephras rings and lava flow, were defined by using a Light Detection and Ranging (LiDAR) survey-based Digital Surface Model (DSM). Finally, the distal tephra associated with explosive eruptions was approximated using published relationships that relate original crater size to ejecta volumes. Considering only those parts with high reliability, the overall magma output (converted to Dense Rock Equivalent) for the post-250 ka active Auckland Volcanic Field in New Zealand is a minimum of 1.704 km3. This is made up of 1.329 km3 in lava flows, 0.067 km3 in phreatomagmatic crater lava infills, 0.090 km3 within tephra/tuff rings, 0.112 km3 inside crater lava infills, and 0.104 km3 within scoria cones. Using the minimum eruptive volumes, the spatial and temporal magma fluxes are estimated at 0.005 km3/km2 and 0.007 km3/ka. The temporal-volumetric evolution of Auckland is
Pituitary volume in children with growth hormone deficiency, idiopathic short stature and controls.
Kessler, Marion; Tenner, Michael; Frey, Michael; Noto, Richard
2016-10-01
The objective of the study was to describe the pituitary volume (PV) in pediatric patients with isolated growth hormone deficiency (IGHD), idiopathic short stature (ISS) and normal controls. Sixty-nine patients (57 male, 12 female), with a mean age of 11.9 (±2.0), were determined to have IGHD. ISS was identified in 29 patients (20 male, 9 female), with a mean age of 12.7 (±3.7). Sixty-six controls (28 female, 38 male), mean age 9.8 (±4.7) were also included. Three-dimensional (3D) magnetic resonance images with contrast were obtained to accurately measure PV. There was a significant difference in the mean PV among the three groups. The IGHD patients had a mean PV 230.8 (±89.6), for ISS patients it was 286.8 (±108.2) and for controls it was 343.7 (±145.9) (pimaging (MRI) could assist in the diagnostic evaluation of the slowly growing child.
Model Predictive Control for Load Frequency Control with Wind Turbines
Yi Zhang
2015-01-01
Full Text Available Reliable load frequency (LFC control is crucial to the operation and design of modern electric power systems. Considering the LFC problem of a four-area interconnected power system with wind turbines, this paper presents a distributed model predictive control (DMPC based on coordination scheme. The proposed algorithm solves a series of local optimization problems to minimize a performance objective for each control area. The scheme incorporates the two critical nonlinear constraints, for example, the generation rate constraint (GRC and the valve limit, into convex optimization problems. Furthermore, the algorithm reduces the impact on the randomness and intermittence of wind turbine effectively. A performance comparison between the proposed controller with and that without the participation of the wind turbines is carried out. Good performance is obtained in the presence of power system nonlinearities due to the governors and turbines constraints and load change disturbances.
A structural model of age, grey matter volumes, education, and personality traits.
Kitamura, Soichiro; Yasuno, Fumihiko; Yamamoto, Akihide; Kazui, Hiroaki; Kudo, Takashi; Matsuoka, Kiwamu; Kiuchi, Kuniaki; Kosaka, Jun; Nagatsuka, Kazuyuki; Iida, Hidehiro; Kishimoto, Toshifumi
2016-01-01
When the relationship between ageing and changes in personality traits is considered, it is important to know how they are influenced by biological and environmental factors. The present study examined the relationships between various factors associated with the effect of ageing on personality traits, including structural changes of the brain and environmental factors such as education. We recruited 41 healthy subjects. We administered the NEO Five-Factor Inventory to assess personality factors. Magnetic resonance imaging was performed, and regional grey matter (GM) volumes were obtained. We identified associations in the correlation analysis of age, cerebral GM volume, years of education, and the personality trait of openness. Path analysis was used to estimate the relationships among these factors. The path analysis model of age, GM volume, years of education, and the personality trait of openness revealed that age has an indirect negative association with openness through GM volume and years of education. Ageing was related to a decrease in GM volume, which was in turn related to a decrease in the openness score. Older subjects generally had fewer years of education, which was related to a lower openness score. Maintaining openness against the effects of ageing is desirable, and our results imply that interventions against age-related cerebral atrophy and the promotion of opportunities for higher education may contribute to the development and stability of a healthy personality during the adult life course. © 2015 The Authors. Psychogeriatrics © 2015 Japanese Psychogeriatric Society.
Huang Gongsheng; Wang Shengwei; Xu Xinhua
2009-01-01
This paper presents a robust model predictive control strategy for improving the supply air temperature control of air-handling units by dealing with the associated uncertainties and constraints directly. This strategy uses a first-order plus time-delay model with uncertain time-delay and system gain to describe air-conditioning process of an air-handling unit usually operating at various weather conditions. The uncertainties of the time-delay and system gain, which imply the nonlinearities and the variable dynamic characteristics, are formulated using an uncertainty polytope. Based on this uncertainty formulation, an offline LMI-based robust model predictive control algorithm is employed to design a robust controller for air-handling units which can guarantee a good robustness subject to uncertainties and constraints. The proposed robust strategy is evaluated in a dynamic simulation environment of a variable air volume air-conditioning system in various operation conditions by comparing with a conventional PI control strategy. The robustness analysis of both strategies under different weather conditions is also presented.
Convertino, V. A.; Benjamin, B. A.; Keil, L. C.; Sandler, H.
1984-01-01
Hemodynamic responses and antidiuretic hormone (ADH) were measured during body position changes, designed to induce central blood volume shifts in ten cardiac and one heart-lung transplant recipients, to assess the contribution of cardiac volume receptors in the control of ADH release during the initial acute phase of exposure to weightlessness. Each subject underwent 15 min of a sitting-control period (C) followed by 30 min of 6 deg headdown tilt (T) and 30 min of resumed sitting (S). Venous blood samples and cardiac dimensions were taken at 0 and 15 min of C; 5, 15, and 30 min of T; and 5, 15, and 30 min of S. Blood samples were analyzed for hematocrit, plasma osmolality, plasma renin activity (PRA), and ADH. Heart rate and blood pressure were recorded every two min. Plasma osmolality was not altered by posture changes. Mean left ventricular end-diastolic volume increased (P less than 0.05) from 90 ml in C to 106 ml in T and returned to 87 ml in S. Plasma ADH was reduced by 20 percent (P less than 0.05) with T, and returned to control levels with S. These responses were similar in six normal cardiac-innervated control subjects. These data may suggest that cardiac volume receptors are not the primary mechanism for the control of ADH release during acute central volume shifts in man.
Baranovskaya T. P.; Loyko V. I.; Makarevich O. A.; Bogoslavskiy S. N.
2014-01-01
The article suggests a mathematical model of optimization of the volume of material flows: the model for the ideal conditions; the model for the working conditions; generalized model of determining the optimal input parameters. These models optimize such parameters of inventory management in technology-integrated grain production systems, as the number of cycles supply, the volume of the source material and financial flows. The study was carried out on the example of the integrated system of ...
Simulation model for wind energy storage systems. Volume III. Program descriptions. [SIMWEST CODE
Warren, A.W.; Edsinger, R.W.; Burroughs, J.D.
1977-08-01
The effort developed a comprehensive computer program for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel and pneumatic). An acronym for the program is SIMWEST (Simulation Model for Wind Energy Storage). The level of detail of SIMWEST is consistent with a role of evaluating the economic feasibility as well as the general performance of wind energy systems. The software package consists of two basic programs and a library of system, environmental, and load components. Volume III, the SIMWEST program description contains program descriptions, flow charts and program listings for the SIMWEST Model Generation Program, the Simulation program, the File Maintenance program and the Printer Plotter program. Volume III generally would not be required by SIMWEST user.
Modeling Accumulated Volume of Landslides Using Remote Sensing and DTM Data
Zhengchao Chen
2014-02-01
Full Text Available Landslides, like other natural hazards, such as avalanches, floods, and debris flows, may result in a lot of property damage and human casualties. The volume of landslide deposits is a key parameter for landslide studies and disaster relief. Using remote sensing and digital terrain model (DTM data, this paper analyzes errors that can occur in calculating landslide volumes using conventional models. To improve existing models, the mechanisms and laws governing the material deposited by landslides are studied and then the mass balance principle and mass balance line are defined. Based on these ideas, a novel and improved model (Mass Balance Model, MBM is proposed. By using a parameter called the “height adaptor”, MBM translates the volume calculation into an automatic search for the mass balance line within the scope of the landslide. Due to the use of mass balance constraints and the height adaptor, MBM is much more effective and reliable. A test of MBM was carried out for the case of a typical landslide, triggered by the Wenchuan Earthquake of 12 May 2008.
2008-10-01
differentiating their products as “ITAR-free”, in the hopes that this can give them a leg up on US producers. To date this “marketing campaign” has...Inspectorate of Strategic Products Slovenia Ministry of Defence Slovakia Ministry of Economy United DTI Export Control Organization [Check] E-41
Model Predictive Control for Smart Energy Systems
Halvgaard, Rasmus
pumps, heat tanks, electrical vehicle battery charging/discharging, wind farms, power plants). 2.Embed forecasting methodologies for the weather (e.g. temperature, solar radiation), the electricity consumption, and the electricity price in a predictive control system. 3.Develop optimization algorithms....... Chapter 3 introduces Model Predictive Control (MPC) including state estimation, filtering and prediction for linear models. Chapter 4 simulates the models from Chapter 2 with the certainty equivalent MPC from Chapter 3. An economic MPC minimizes the costs of consumption based on real electricity prices...... that determined the flexibility of the units. A predictive control system easily handles constraints, e.g. limitations in power consumption, and predicts the future behavior of a unit by integrating predictions of electricity prices, consumption, and weather variables. The simulations demonstrate the expected...
Parametric uncertainty modeling for robust control
Rasmussen, K.H.; Jørgensen, Sten Bay
1999-01-01
The dynamic behaviour of a non-linear process can often be approximated with a time-varying linear model. In the presented methodology the dynamics is modeled non-conservatively as parametric uncertainty in linear lime invariant models. The obtained uncertainty description makes it possible...... to perform robustness analysis on a control system using the structured singular value. The idea behind the proposed method is to fit a rational function to the parameter variation. The parameter variation can then be expressed as a linear fractional transformation (LFT), It is discussed how the proposed...... point changes. It is shown that a diagonal PI control structure provides robust performance towards variations in feed flow rate or feed concentrations. However including both liquid and vapor flow delays robust performance specifications cannot be satisfied with this simple diagonal control structure...
Modelling and control of dynamic systems using gaussian process models
Kocijan, Juš
2016-01-01
This monograph opens up new horizons for engineers and researchers in academia and in industry dealing with or interested in new developments in the field of system identification and control. It emphasizes guidelines for working solutions and practical advice for their implementation rather than the theoretical background of Gaussian process (GP) models. The book demonstrates the potential of this recent development in probabilistic machine-learning methods and gives the reader an intuitive understanding of the topic. The current state of the art is treated along with possible future directions for research. Systems control design relies on mathematical models and these may be developed from measurement data. This process of system identification, when based on GP models, can play an integral part of control design in data-based control and its description as such is an essential aspect of the text. The background of GP regression is introduced first with system identification and incorporation of prior know...
Modeling, Optimization & Control of Hydraulic Networks
Tahavori, Maryamsadat
2014-01-01
. The nonlinear network model is derived based on the circuit theory. A suitable projection is used to reduce the state vector and to express the model in standard state-space form. Then, the controllability of nonlinear nonaffine hydraulic networks is studied. The Lie algebra-based controllability matrix is used......Water supply systems consist of a number of pumping stations, which deliver water to the customers via pipeline networks and elevated reservoirs. A huge amount of drinking water is lost before it reaches to end-users due to the leakage in pipe networks. A cost effective solution to reduce leakage...... in water network is pressure management. By reducing the pressure in the water network, the leakage can be reduced significantly. Also it reduces the amount of energy consumption in water networks. The primary purpose of this work is to develop control algorithms for pressure control in water supply...
Dynamic modeling and control of CFSTF
Danesh, Y.; Jalali Farahani, F.
2001-01-01
This paper deals with the modeling and control of a continuous-flow fermentation process for the production of alcohol: The dynamic behavior of ferment ors has been developed from mass balance and leads to nonlinear differential equations. Based on the proposed model, two computer algorithms are provided to control output alcohol concentration at the desired value by input flow rate manipulation. The first algorithm is based on a conventional Proportional-Integral-Derivative, in which its parameters are determined in a trial and error procedure. The second algorithm is based on optimal controllers. In this way, the difference between output alcohol concentration and desired value is minimized by flow rate manipulation. Minimization (optimization) is done based on the MARQYARDT procedure. The advantages of this method over the conventional Proportional-Integral-Derivative controller are its higher speed and lack of overshoot
Validation of Storm Water Management Model Storm Control Measures Modules
Simon, M. A.; Platz, M. C.
2017-12-01
EPA's Storm Water Management Model (SWMM) is a computational code heavily relied upon by industry for the simulation of wastewater and stormwater infrastructure performance. Many municipalities are relying on SWMM results to design multi-billion-dollar, multi-decade infrastructure upgrades. Since the 1970's, EPA and others have developed five major releases, the most recent ones containing storm control measures modules for green infrastructure. The main objective of this study was to quantify the accuracy with which SWMM v5.1.10 simulates the hydrologic activity of previously monitored low impact developments. Model performance was evaluated with a mathematical comparison of outflow hydrographs and total outflow volumes, using empirical data and a multi-event, multi-objective calibration method. The calibration methodology utilized PEST++ Version 3, a parameter estimation tool, which aided in the selection of unmeasured hydrologic parameters. From the validation study and sensitivity analysis, several model improvements were identified to advance SWMM LID Module performance for permeable pavements, infiltration units and green roofs, and these were performed and reported herein. Overall, it was determined that SWMM can successfully simulate low impact development controls given accurate model confirmation, parameter measurement, and model calibration.
Ising model for packet routing control
Horiguchi, Tsuyoshi; Takahashi, Hideyuki; Hayashi, Keisuke; Yamaguchi, Chiaki
2004-01-01
For packet routing control in computer networks, we propose an Ising model which is defined in order to express competition among a queue length and a distance from a node with a packet to its destination node. By introducing a dynamics for a mean-field value of an Ising spin, we show by computer simulations that effective control of packet routing through priority links is possible
Measurement control program at model facility
Schneider, R.A.
1984-01-01
A measurement control program for the model plant is described. The discussion includes the technical basis for such a program, the application of measurement control principles to each measurement, and the use of special experiments to estimate measurement error parameters for difficult-to-measure materials. The discussion also describes the statistical aspects of the program, and the documentation procedures used to record, maintain, and process the basic data
Optimization control of LNG regasification plant using Model Predictive Control
Wahid, A.; Adicandra, F. F.
2018-03-01
Optimization of liquified natural gas (LNG) regasification plant is important to minimize costs, especially operational costs. Therefore, it is important to choose optimum LNG regasification plant design and maintaining the optimum operating conditions through the implementation of model predictive control (MPC). Optimal tuning parameter for MPC such as P (prediction horizon), M (control of the horizon) and T (sampling time) are achieved by using fine-tuning method. The optimal criterion for design is the minimum amount of energy used and for control is integral of square error (ISE). As a result, the optimum design is scheme 2 which is developed by Devold with an energy savings of 40%. To maintain the optimum conditions, required MPC with P, M and T as follows: tank storage pressure: 90, 2, 1; product pressure: 95, 2, 1; temperature vaporizer: 65, 2, 2; and temperature heater: 35, 6, 5, with ISE value at set point tracking respectively 0.99, 1792.78, 34.89 and 7.54, or improvement of control performance respectively 4.6%, 63.5%, 3.1% and 58.2% compared to PI controller performance. The energy savings that MPC controllers can make when there is a disturbance in temperature rise 1°C of sea water is 0.02 MW.
Gmel Gerrit
2010-03-01
Full Text Available Abstract Background Alcohol consumption is a major risk factor in the global burden of disease, with overall volume of exposure as the principal underlying dimension. Two main sources of data on volume of alcohol exposure are available: surveys and per capita consumption derived from routine statistics such as taxation. As both sources have significant problems, this paper presents an approach that triangulates information from both sources into disaggregated estimates in line with the overall level of per capita consumption. Methods A modeling approach was applied to the US using data from a large and representative survey, the National Epidemiologic Survey on Alcohol and Related Conditions. Different distributions (log-normal, gamma, Weibull were used to model consumption among drinkers in subgroups defined by sex, age, and ethnicity. The gamma distribution was used to shift the fitted distributions in line with the overall volume as derived from per capita estimates. Implications for alcohol-attributable fractions were presented, using liver cirrhosis as an example. Results The triangulation of survey data with aggregated per capita consumption data proved feasible and allowed for modeling of alcohol exposure disaggregated by sex, age, and ethnicity. These models can be used in combination with risk relations for burden of disease calculations. Sensitivity analyses showed that the gamma distribution chosen yielded very similar results in terms of fit and alcohol-attributable mortality as the other tested distributions. Conclusions Modeling alcohol consumption via the gamma distribution was feasible. To further refine this approach, research should focus on the main assumptions underlying the approach to explore differences between volume estimates derived from surveys and per capita consumption figures.
Woods, D.D.; Roth, E.M.; Hanes, L.F.
1986-07-01
This report contains the results of a feasibility study to determine if the current state of models human cognitive activities can serve as the basis for improved techniques for predicting human error in nuclear power plants emergency operations. Based on the answer to this questions, two subsequent phases of research are planned. Phase II is to develop a model of cognitive activities, and Phase III is to test the model. The feasibility study included an analysis of the cognitive activities that occur in emergency operations and an assessment of the modeling concepts/tools available to capture these cognitive activities. The results indicated that a symbolic processing (or artificial intelligence) model of cognitive activities in nuclear power plants is both desirable and feasible. This cognitive model can be built upon the computational framework provided by an existing artificial intelligence system for medical problem solving called Caduceus. The resulting cognitive model will increase the capability to capture the human contribution to risk in probabilistic risk assessments studies. Volume I summarizes the major findings and conclusions of the study. Volume II provides a complete description of the methods and results, including a synthesis of the cognitive activities that occur during emergency operations, and a literature review on cognitive modeling relevant to nuclear power plants. 112 refs., 10 figs
Model predictive control of a wind turbine modelled in Simpack
Jassmann, U; Matzke, D; Reiter, M; Abel, D; Berroth, J; Schelenz, R; Jacobs, G
2014-01-01
Wind turbines (WT) are steadily growing in size to increase their power production, which also causes increasing loads acting on the turbine's components. At the same time large structures, such as the blades and the tower get more flexible. To minimize this impact, the classical control loops for keeping the power production in an optimum state are more and more extended by load alleviation strategies. These additional control loops can be unified by a multiple-input multiple-output (MIMO) controller to achieve better balancing of tuning parameters. An example for MIMO control, which has been paid more attention to recently by wind industry, is Model Predictive Control (MPC). In a MPC framework a simplified model of the WT is used to predict its controlled outputs. Based on a user-defined cost function an online optimization calculates the optimal control sequence. Thereby MPC can intrinsically incorporate constraints e.g. of actuators. Turbine models used for calculation within the MPC are typically simplified. For testing and verification usually multi body simulations, such as FAST, BLADED or FLEX5 are used to model system dynamics, but they are still limited in the number of degrees of freedom (DOF). Detailed information about load distribution (e.g. inside the gearbox) cannot be provided by such models. In this paper a Model Predictive Controller is presented and tested in a co-simulation with SlMPACK, a multi body system (MBS) simulation framework used for detailed load analysis. The analysis are performed on the basis of the IME6.0 MBS WT model, described in this paper. It is based on the rotor of the NREL 5MW WT and consists of a detailed representation of the drive train. This takes into account a flexible main shaft and its main bearings with a planetary gearbox, where all components are modelled flexible, as well as a supporting flexible main frame. The wind loads are simulated using the NREL AERODYN v13 code which has been implemented as a routine
Model predictive control of a wind turbine modelled in Simpack
Jassmann, U.; Berroth, J.; Matzke, D.; Schelenz, R.; Reiter, M.; Jacobs, G.; Abel, D.
2014-06-01
Wind turbines (WT) are steadily growing in size to increase their power production, which also causes increasing loads acting on the turbine's components. At the same time large structures, such as the blades and the tower get more flexible. To minimize this impact, the classical control loops for keeping the power production in an optimum state are more and more extended by load alleviation strategies. These additional control loops can be unified by a multiple-input multiple-output (MIMO) controller to achieve better balancing of tuning parameters. An example for MIMO control, which has been paid more attention to recently by wind industry, is Model Predictive Control (MPC). In a MPC framework a simplified model of the WT is used to predict its controlled outputs. Based on a user-defined cost function an online optimization calculates the optimal control sequence. Thereby MPC can intrinsically incorporate constraints e.g. of actuators. Turbine models used for calculation within the MPC are typically simplified. For testing and verification usually multi body simulations, such as FAST, BLADED or FLEX5 are used to model system dynamics, but they are still limited in the number of degrees of freedom (DOF). Detailed information about load distribution (e.g. inside the gearbox) cannot be provided by such models. In this paper a Model Predictive Controller is presented and tested in a co-simulation with SlMPACK, a multi body system (MBS) simulation framework used for detailed load analysis. The analysis are performed on the basis of the IME6.0 MBS WT model, described in this paper. It is based on the rotor of the NREL 5MW WT and consists of a detailed representation of the drive train. This takes into account a flexible main shaft and its main bearings with a planetary gearbox, where all components are modelled flexible, as well as a supporting flexible main frame. The wind loads are simulated using the NREL AERODYN v13 code which has been implemented as a routine to
Model Based Control of Reefer Container Systems
Sørensen, Kresten Kjær
This thesis is concerned with the development of model based control for the Star Cool refrigerated container (reefer) with the objective of reducing energy consumption. This project has been carried out under the Danish Industrial PhD programme and has been financed by Lodam together with the Da......This thesis is concerned with the development of model based control for the Star Cool refrigerated container (reefer) with the objective of reducing energy consumption. This project has been carried out under the Danish Industrial PhD programme and has been financed by Lodam together...
Ge, Ying; Wan, Yong; Wang, Da-qing; Su, Xiao-lin; Li, Jun-ying; Chen, Jing
2004-07-01
To investigate the significance and effect of pressure controlled ventilation (PCV) as well as volume controlled ventilation (VCV) by lung protective strategy on respiratory mechanics, blood gas analysis and hemodynamics in patients with acute respiratory distress syndrome (ARDS). Fifty patients with ARDS were randomly divided into PCV and VCV groups with permissive hypercapnia and open lung strategy. Changes in respiratory mechanics, blood gas analysis and hemodynamics were compared between two groups. Peak inspiration pressure (PIP) in PCV group was significantly lower than that in VCV group, while mean pressure of airway (MPaw) was significantly higher than that in VCV after 24 hours mechanical ventilation. After 24 hours mechanical ventilation, there were higher central venous pressure (CVP) and slower heart rate (HR) in two groups, CVP was significantly higher in VCV compared with PCV, and PCV group had slower HR than VCV group, the two groups had no differences in mean blood pressure (MBP) at various intervals. All patients showed no ventilator-induced lung injury. Arterial blood oxygenations were obviously improved in two groups after 24 hours mechanical ventilation, PCV group had better partial pressure of oxygen in artery (PaO2) than VCV group. Both PCV and VCV can improve arterial blood oxygenations, prevent ventilator-induced lung injury, and have less disturbance in hemodynamic parameters. PCV with lung protective ventilatory strategy should be early use for patients with ARDS.
Modelling and Control of Magnetorheological Damper
Bhowmik, Subrata
, used as reference case for assessment of the proposed control methods with negative stiffness. Viscous damping with negative stiffness (VDNS) initially illustrates the effectiveness of the negative stiffness component in structural damping. In a linear control setting negative stiffness requires active...... damper is identified by both the standard parametric Bouc-Wen model and the non-parametric neural network model from an experimental data set generated by dynamic tests of the MR damper mounted in a hydraulic testing machine. The forward model represents the direct dynamics of the MR damper where...... are essential input parameters for the MR damper modelling. Thus, for proper training, the quality of the velocity data is very important. However, direct velocity measurement is not easy. From the displacement data or the acceleration data, velocity can be determined by using simple differentiation...
Sarmad ISTEPHAN
2015-06-01
Full Text Available Volumetric medical image datasets contain vital information for noninvasive diagnosis, treatment planning and prognosis. However, direct and unlimited query of such datasets is hindered due to the unstructured nature of the imaging data. This study is a step towards the unlimited query of medical image datasets by focusing on specific Structures of Interest (SOI. A requirement in achieving this objective is having both the surface and volume models of the SOI. However, typically, only the surface model is available. Therefore, this study focuses on creating a fast method to convert a surface model to a volume model. Three methods (1D, 2D and 3D are proposed and evaluated using simulated and real data of Deep Perisylvian Area (DPSA within the human brain. The 1D method takes 80 msec for DPSA model; about 4 times faster than 2D method and 7.4 fold faster than 3D method, with over 97% accuracy. The proposed 1D method is feasible for surface to volume conversion in computer aided diagnosis, treatment planning and prognosis systems containing large amounts of unstructured medical images.
Iterative model reconstruction reduces calcified plaque volume in coronary CT angiography
Károlyi, Mihály, E-mail: mihaly.karolyi@cirg.hu [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Szilveszter, Bálint, E-mail: szilveszter.balint@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Kolossváry, Márton, E-mail: martonandko@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Takx, Richard A.P, E-mail: richard.takx@gmail.com [Department of Radiology, University Medical Center Utrecht, 100 Heidelberglaan, 3584, CX Utrecht (Netherlands); Celeng, Csilla, E-mail: celengcsilla@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Bartykowszki, Andrea, E-mail: bartyandi@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Jermendy, Ádám L., E-mail: adam.jermendy@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Panajotu, Alexisz, E-mail: panajotualexisz@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Karády, Júlia, E-mail: karadyjulia@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); and others
2017-02-15
Objective: To assess the impact of iterative model reconstruction (IMR) on calcified plaque quantification as compared to filtered back projection reconstruction (FBP) and hybrid iterative reconstruction (HIR) in coronary computed tomography angiography (CTA). Methods: Raw image data of 52 patients who underwent 256-slice CTA were reconstructed with IMR, HIR and FBP. We evaluated qualitative, quantitative image quality parameters and quantified calcified and partially calcified plaque volumes using automated software. Results: Overall qualitative image quality significantly improved with HIR as compared to FBP, and further improved with IMR (p < 0.01 all). Contrast-to-noise ratios were improved with IMR, compared to HIR and FBP (51.0 [43.5–59.9], 20.3 [16.2–25.9] and 14.0 [11.2–17.7], respectively, all p < 0.01) Overall plaque volumes were lowest with IMR and highest with FBP (121.7 [79.3–168.4], 138.7 [90.6–191.7], 147.0 [100.7–183.6]). Similarly, calcified volumes (>130 HU) were decreased with IMR as compared to HIR and FBP (105.9 [62.1–144.6], 110.2 [63.8–166.6], 115.9 [81.7–164.2], respectively, p < 0.05 all). High-attenuation non-calcified volumes (90–129 HU) yielded similar values with FBP and HIR (p = 0.81), however it was lower with IMR (p < 0.05 both). Intermediate- (30–89 HU) and low-attenuation (<30 HU) non-calcified volumes showed no significant difference (p = 0.22 and p = 0.67, respectively). Conclusions: IMR improves image quality of coronary CTA and decreases calcified plaque volumes.
Model Predictive Control of Wind Turbines
Henriksen, Lars Christian
Wind turbines play a major role in the transformation from a fossil fuel based energy production to a more sustainable production of energy. Total-cost-of-ownership is an important parameter when investors decide in which energy technology they should place their capital. Modern wind turbines...... the need for maintenance of the wind turbine. Either way, better total-cost-of-ownership for wind turbine operators can be achieved by improved control of the wind turbines. Wind turbine control can be improved in two ways, by improving the model on which the controller bases its design or by improving...
Model Predictive Control of Sewer Networks
Pedersen, Einar B.; Herbertsson, Hannes R.; Niemann, Henrik
2016-01-01
The developments in solutions for management of urban drainage are of vital importance, as the amount of sewer water from urban areas continues to increase due to the increase of the world’s population and the change in the climate conditions. How a sewer network is structured, monitored and cont...... benchmark model. Due to the inherent constraints the applied approach is based on Model Predictive Control....
Charlotte J Beurskens
Full Text Available BACKGROUND: Helium is a noble gas with a low density, allowing for lower driving pressures and increased carbon dioxide (CO2 diffusion. Since application of protective ventilation can be limited by the development of hypoxemia or acidosis, we hypothesized that therefore heliox facilitates ventilation in an animal model of ventilator-induced lung injury. METHODS: Sprague-Dawley rats (N=8 per group were mechanically ventilated with heliox (50% oxygen; 50% helium. Controls received a standard gas mixture (50% oxygen; 50% air. VILI was induced by application of tidal volumes of 15 mL kg(-1; lung protective ventilated animals were ventilated with 6 mL kg(-1. Respiratory parameters were monitored with a pneumotach system. Respiratory rate was adjusted to maintain arterial pCO2 within 4.5-5.5 kPa, according to hourly drawn arterial blood gases. After 4 hours, bronchoalveolar lavage fluid (BALF was obtained. Data are mean (SD. RESULTS: VILI resulted in an increase in BALF protein compared to low tidal ventilation (629 (324 vs. 290 (181 μg mL(-1; p<0.05 and IL-6 levels (640 (8.7 vs. 206 (8.7 pg mL(-1; p<0.05, whereas cell counts did not differ between groups after this short course of mechanical ventilation. Ventilation with heliox resulted in a decrease in mean respiratory minute volume ventilation compared to control (123 ± 0.6 vs. 146 ± 8.9 mL min(-1, P<0.001, due to a decrease in respiratory rate (22 (0.4 vs. 25 (2.1 breaths per minute; p<0.05, while pCO2 levels and tidal volumes remained unchanged, according to protocol. There was no effect of heliox on inspiratory pressure, while compliance was reduced. In this mild lung injury model, heliox did not exert anti-inflammatory effects. CONCLUSIONS: Heliox allowed for a reduction in respiratory rate and respiratory minute volume during VILI, while maintaining normal acid-base balance. Use of heliox may be a useful approach when protective tidal volume ventilation is limited by the development of
Control system modelling for superconducting accelerator
Czarski, T.; Pozniak, K.; Romaniuk, R.
2006-01-01
A digital control of superconducting cavities for a linear accelerator is presented. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. FPGA based controller supported by MATLAB system was developed to investigate the novel firmware implementation. Algebraic model in complex domain is proposed for the system analyzing. Calibration procedure of a signal path is considered for a multi-channel control. Identification of the system parameters is carried out by the least squares method application. Control tables: Feed-Forward and Set- Point are determined for the required cavity performance, according to the recognized process. Feedback loop is tuned by fitting a complex gain of a corrector unit. Adaptive control algorithm is applied for feed-forward and feedback modes. Experimental results are presented for a cavity representative operation. (orig.)
Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1
Lee, F. C.; Mahmoud, M. F.; Yu, Y.
1980-01-01
The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.
Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1
Lee, F. C.; Mahmoud, M. F.; Yu, Y.
1980-04-01
The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.
Monte Carlo method for critical systems in infinite volume: The planar Ising model.
Herdeiro, Victor; Doyon, Benjamin
2016-10-01
In this paper we propose a Monte Carlo method for generating finite-domain marginals of critical distributions of statistical models in infinite volume. The algorithm corrects the problem of the long-range effects of boundaries associated to generating critical distributions on finite lattices. It uses the advantage of scale invariance combined with ideas of the renormalization group in order to construct a type of "holographic" boundary condition that encodes the presence of an infinite volume beyond it. We check the quality of the distribution obtained in the case of the planar Ising model by comparing various observables with their infinite-plane prediction. We accurately reproduce planar two-, three-, and four-point of spin and energy operators. We also define a lattice stress-energy tensor, and numerically obtain the associated conformal Ward identities and the Ising central charge.
Simulation model for wind energy storage systems. Volume II. Operation manual. [SIMWEST code
Warren, A.W.; Edsinger, R.W.; Burroughs, J.D.
1977-08-01
The effort developed a comprehensive computer program for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel and pneumatic). An acronym for the program is SIMWEST (Simulation Model for Wind Energy Storage). The level of detail of SIMWEST is consistent with a role of evaluating the economic feasibility as well as the general performance of wind energy systems. The software package consists of two basic programs and a library of system, environmental, and load components. Volume II, the SIMWEST operation manual, describes the usage of the SIMWEST program, the design of the library components, and a number of simple example simulations intended to familiarize the user with the program's operation. Volume II also contains a listing of each SIMWEST library subroutine.
V. Balaji
2016-12-01
Full Text Available pH control plays a important role in any chemical plant and process industries. For the past four decades the classical PID controller has been occupied by the industries. Due to the faster computing technology in the industry demands a tighter advanced control strategy. To fulfill the needs and requirements Model Predictive Control (MPC is the best among all the advanced control algorithms available in the present scenario. The study and analysis has been done for First Order plus Delay Time (FOPDT model controlled by Proportional Integral Derivative (PID and MPC using the Matlab software. This paper explores the capability of the MPC strategy, analyze and compare the control effects with conventional control strategy in pH control. A comparison results between the PID and MPC is plotted using the software. The results clearly show that MPC provide better performance than the classical controller.
Model based design of electronic throttle control
Cherian, Fenin; Ranjan, Ashish; Bhowmick, Pathikrit; Rammohan, A.
2017-11-01
With the advent of torque based Engine Management Systems, the precise control and robust performance of the throttle body becomes a key factor in the overall performance of the vehicle. Electronic Throttle Control provides benefits such as improved air-fuel ratio for improving the vehicle performance and lower exhausts emissions to meet the stringent emission norms. Modern vehicles facilitate various features such as Cruise Control, Traction Control, Electronic Stability Program and Pre-crash systems. These systems require control over engine power without driver intervention, which is not possible with conventional mechanical throttle system. Thus these systems are integrated to function with the electronic throttle control. However, due to inherent non-linearities in the throttle body, the control becomes a difficult task. In order to eliminate the influence of this hysteresis at the initial operation of the butterfly valve, a control to compensate the shortage must be added to the duty required for starting throttle operation when the initial operation is detected. Therefore, a lot of work is being done in this field to incorporate the various nonlinearities to achieve robust control. In our present work, the ETB was tested to verify the working of the system. Calibration of the TPS sensors was carried out in order to acquire accurate throttle opening angle. The response of the calibrated system was then plotted against a step input signal. A linear model of the ETB was prepared using Simulink and its response was compared with the experimental data to find out the initial deviation of the model from the actual system. To reduce this deviation, non-linearities from existing literature were introduced to the system and a response analysis was performed to check the deviation from the actual system. Based on this investigation, an introduction of a new nonlinearity parameter can be used in future to reduce the deviation further making the control of the ETB more
Model based control of grate combustion; Modellbaserad roststyrning
Broden, Henrik; Kjellstroem, Bjoern; Niklasson, Fredrik; Boecher Poulsen, Kristian
2006-12-15
An existing dynamic model for grate combustion has been further developed. The model has been used for studies of possible advantages that can be gained from utilisation of measurements of grate temperatures and fuel bed height for control of a boiler after disturbances caused by varying fuel moisture and fuel feeding. The objective was to asses the possibilities to develop a control system that would adjust for such disturbances quicker than measurements of steam output and oxygen in the exhaust. The model is based on dividing the fuel bed into three layers, where the different layers include fuel being dried, fuel being pyrolysed and char reacting with oxygen. The grate below the fuel bed is also considered. A mass balance, an energy balance and a volume balance is considered for each layer in 22 cells along the grate. The energy balances give the temperature distribution and the volume balances the bed height. The earlier version of the model could not handle layers that are consumed. This weakness has now been eliminated. Comparisons between predicted grate temperatures and measurements in a 25 MW boiler fuelled with biofuel have been used for validation of the model. The comparisons include effects of variations in primary air temperature, fuel moisture and output power. The model shows good agreement with observations for changes in the air temperature but the ability of the model to predict effects of changed fuel moisture is difficult to judge since the steam dome pressure control caused simultaneous changes of the primary air flow, which probably had a larger influence on the grate temperature. A linearised, tuned and reduced version of the model was used for design of a linear quadratic controller. This was used for studies of advantages of using measurements of grate temperatures and bed height for control of pusher velocity, grate speed, primary air flow and air temperature after disturbances of fuel moisture and fuel flow. Measurements of the grate
Gu, Wan-Jie; Wang, Fei; Liu, Jing-Chen
2015-02-17
In anesthetized patients undergoing surgery, the role of lung-protective ventilation with lower tidal volumes is unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of this ventilation strategy on postoperative outcomes. We searched electronic databases from inception through September 2014. We included RCTs that compared protective ventilation with lower tidal volumes and conventional ventilation with higher tidal volumes in anesthetized adults undergoing surgery. We pooled outcomes using a random-effects model. The primary outcome measures were lung injury and pulmonary infection. We included 19 trials (n=1348). Compared with patients in the control group, those who received lung-protective ventilation had a decreased risk of lung injury (risk ratio [RR] 0.36, 95% confidence interval [CI] 0.17 to 0.78; I2=0%) and pulmonary infection (RR 0.46, 95% CI 0.26 to 0.83; I2=8%), and higher levels of arterial partial pressure of carbon dioxide (standardized mean difference 0.47, 95% CI 0.18 to 0.75; I2=65%). No significant differences were observed between the patient groups in atelectasis, mortality, length of hospital stay, length of stay in the intensive care unit or the ratio of arterial partial pressure of oxygen to fraction of inspired oxygen. Anesthetized patients who received ventilation with lower tidal volumes during surgery had a lower risk of lung injury and pulmonary infection than those given conventional ventilation with higher tidal volumes. Implementation of a lung-protective ventilation strategy with lower tidal volumes may lower the incidence of these outcomes. © 2015 Canadian Medical Association or its licensors.
Model based control of refrigeration systems
Sloth Larsen, L.F.
2005-11-15
The subject for this Ph.D. thesis is model based control of refrigeration systems. Model based control covers a variety of different types of controls, that incorporates mathematical models. In this thesis the main subject therefore has been restricted to deal with system optimizing control. The optimizing control is divided into two layers, where the system oriented top layers deals with set-point optimizing control and the lower layer deals with dynamical optimizing control in the subsystems. The thesis has two main contributions, i.e. a novel approach for set-point optimization and a novel approach for desynchronization based on dynamical optimization. The focus in the development of the proposed set-point optimizing control has been on deriving a simple and general method, that with ease can be applied on various compositions of the same class of systems, such as refrigeration systems. The method is based on a set of parameter depended static equations describing the considered process. By adapting the parameters to the given process, predict the steady state and computing a steady state gradient of the cost function, the process can be driven continuously towards zero gradient, i.e. the optimum (if the cost function is convex). The method furthermore deals with system constrains by introducing barrier functions, hereby the best possible performance taking the given constrains in to account can be obtained, e.g. under extreme operational conditions. The proposed method has been applied on a test refrigeration system, placed at Aalborg University, for minimization of the energy consumption. Here it was proved that by using general static parameter depended system equations it was possible drive the set-points close to the optimum and thus reduce the power consumption with up to 20%. In the dynamical optimizing layer the idea is to optimize the operation of the subsystem or the groupings of subsystems, that limits the obtainable system performance. In systems
Silvane Vatraz
2014-01-01
Full Text Available The objective of this research was to improve the operating procedures of control of the volume of timber estimated by the forest inventory and the effectively harvested volume in order to reduce inconsistencies in the forest planning practiced in a forestry plantation of Pinus spp. in Paraná state. Accordingly, we used the tools of quality: storming and PDCA Cycle through an exploratory research project to study together. The study showed an inconsistency initial volume – 24,73% of the volume estimated by the inventory and the effectively harvested wood. This inconsistency was composed of operational failures in the activities of Forest Inventory (+13,84%, Forest Harvesting (+15,62% and Expedition Wood (-3,08%. The application of quality tools helped in the identification of inconsistency, as well as the revelation of operational failures, which suggested some routine monitoring and checking each of the activities involved in managing operational forestry.
Demand modelling of passenger air travel: An analysis and extension, volume 2
Jacobson, I. D.
1978-01-01
Previous intercity travel demand models in terms of their ability to predict air travel in a useful way and the need for disaggregation in the approach to demand modelling are evaluated. The viability of incorporating non-conventional factors (i.e. non-econometric, such as time and cost) in travel demand forecasting models are determined. The investigation of existing models is carried out in order to provide insight into their strong points and shortcomings. The model is characterized as a market segmentation model. This is a consequence of the strengths of disaggregation and its natural evolution to a usable aggregate formulation. The need for this approach both pedagogically and mathematically is discussed. In addition this volume contains two appendices which should prove useful to the non-specialist in the area.
Modelling the Hydraulic Behaviour of Growing Media with the Explicit Finite Volume Solution
Marco Carbone
2015-02-01
Full Text Available The increasing imperviousness of urban areas reduces the infiltration and evapotranspiration capacity of urban catchments and results in increased runoff. In the last few decades, several solutions and techniques have been proposed to prevent such impacts by restoring the hydrological cycle. A limiting factor in spreading the use of such systems is the lack of proper modelling tools for design, especially for the infiltration processes in a growing medium. In this research, a physically-based model, employing the explicit Finite Volume Method (FVM, is proposed for modelling infiltration into growing media. The model solves a modified version of the Richards equation using a formulation which takes into account the main characteristics of green infrastructure substrates. The proposed model was verified against the HYDRUS-1D software and the comparison of results confirmed the suitability of the proposed model for correctly describing the hydraulic behaviour of soil substrates.
Montgomery, David W. G.; Amira, Abbes; Zaidi, Habib
2007-01-01
The widespread application of positron emission tomography (PET) in clinical oncology has driven this imaging technology into a number of new research and clinical arenas. Increasing numbers of patient scans have led to an urgent need for efficient data handling and the development of new image analysis techniques to aid clinicians in the diagnosis of disease and planning of treatment. Automatic quantitative assessment of metabolic PET data is attractive and will certainly revolutionize the practice of functional imaging since it can lower variability across institutions and may enhance the consistency of image interpretation independent of reader experience. In this paper, a novel automated system for the segmentation of oncological PET data aiming at providing an accurate quantitative analysis tool is proposed. The initial step involves expectation maximization (EM)-based mixture modeling using a k-means clustering procedure, which varies voxel order for initialization. A multiscale Markov model is then used to refine this segmentation by modeling spatial correlations between neighboring image voxels. An experimental study using an anthropomorphic thorax phantom was conducted for quantitative evaluation of the performance of the proposed segmentation algorithm. The comparison of actual tumor volumes to the volumes calculated using different segmentation methodologies including standard k-means, spatial domain Markov Random Field Model (MRFM), and the new multiscale MRFM proposed in this paper showed that the latter dramatically reduces the relative error to less than 8% for small lesions (7 mm radii) and less than 3.5% for larger lesions (9 mm radii). The analysis of the resulting segmentations of clinical oncologic PET data seems to confirm that this methodology shows promise and can successfully segment patient lesions. For problematic images, this technique enables the identification of tumors situated very close to nearby high normal physiologic uptake. The
Applying ARIMA model for annual volume time series of the Magdalena River
Gloria Amaris; Humberto Ávila; Thomas Guerrero
2017-01-01
Context: Climate change effects, human interventions, and river characteristics are factors that increase the risk on the population and the water resources. However, negative impacts such as flooding, and river droughts may be previously identified using appropriate numerical tools. Objectives: The annual volume (Millions of m3/year) time series of the Magdalena River was analyzed by an ARIMA model, using the historical time series of the Calamar station (Instituto de Hidrología, Meteoro...
Wagner, Maximilian E H; Gellrich, Nils-Claudius; Friese, Karl-Ingo; Becker, Matthias; Wolter, Franz-Erich; Lichtenstein, Juergen T; Stoetzer, Marcus; Rana, Majeed; Essig, Harald
2016-01-01
Objective determination of the orbital volume is important in the diagnostic process and in evaluating the efficacy of medical and/or surgical treatment of orbital diseases. Tools designed to measure orbital volume with computed tomography (CT) often cannot be used with cone beam CT (CBCT) because of inferior tissue representation, although CBCT has the benefit of greater availability and lower patient radiation exposure. Therefore, a model-based segmentation technique is presented as a new method for measuring orbital volume and compared to alternative techniques. Both eyes from thirty subjects with no known orbital pathology who had undergone CBCT as a part of routine care were evaluated (n = 60 eyes). Orbital volume was measured with manual, atlas-based, and model-based segmentation methods. Volume measurements, volume determination time, and usability were compared between the three methods. Differences in means were tested for statistical significance using two-tailed Student's t tests. Neither atlas-based (26.63 ± 3.15 mm(3)) nor model-based (26.87 ± 2.99 mm(3)) measurements were significantly different from manual volume measurements (26.65 ± 4.0 mm(3)). However, the time required to determine orbital volume was significantly longer for manual measurements (10.24 ± 1.21 min) than for atlas-based (6.96 ± 2.62 min, p < 0.001) or model-based (5.73 ± 1.12 min, p < 0.001) measurements. All three orbital volume measurement methods examined can accurately measure orbital volume, although atlas-based and model-based methods seem to be more user-friendly and less time-consuming. The new model-based technique achieves fully automated segmentation results, whereas all atlas-based segmentations at least required manipulations to the anterior closing. Additionally, model-based segmentation can provide reliable orbital volume measurements when CT image quality is poor.
Van Konynenburg, R.A.; McCright, R.D.; Roy, A.K.; Jones, D.A.
1995-08-01
This three-volume report serves several purposes. The first volume provides an introduction to the engineered materials effort for the Yucca Mountain Site Characterization Project. It defines terms and outlines the history of selection and characterization of these materials. A summary of the recent engineered barrier materials characterization workshop is presented, and the current candidate materials are listed. The second volume tabulates design data for engineered materials, and the third volume is devoted to corrosion data, radiation effects on corrosion, and corrosion modeling. The second and third volumes are intended to be evolving documents, to which new data will be added as they become available from additional studies. The initial version of Volume 3 is devoted to information currently available for environments most similar to those expected in the potential Yucca Mountain repository. This is volume three
Larsen, Fin Stolze; Schmidt, Lars Ebbe; Bernsmeier, Christine; Rasmussen, Allan; Isoniemi, Helena; Patel, Vishal C; Triantafyllou, Evangelos; Bernal, William; Auzinger, Georg; Shawcross, Debbie; Eefsen, Martin; Bjerring, Peter Nissen; Clemmesen, Jens Otto; Hockerstedt, Krister; Frederiksen, Hans-Jørgen; Hansen, Bent Adel; Antoniades, Charalambos G; Wendon, Julia
2016-01-01
Acute liver failure (ALF) often results in cardiovascular instability, renal failure, brain oedema and death either due to irreversible shock, cerebral herniation or development of multiple organ failure. High-volume plasma exchange (HVP), defined as exchange of 8-12 or 15% of ideal body weight with fresh frozen plasma in case series improves systemic, cerebral and splanchnic parameters. In this prospective, randomised, controlled, multicentre trial we randomly assigned 182 patients with ALF to receive either standard medical therapy (SMT; 90 patients) or SMT plus HVP for three days (92 patients). The baseline characteristics of the groups were similar. The primary endpoint was liver transplantation-free survival during hospital stay. Secondary-endpoints included survival after liver transplantation with or without HVP with intention-to-treat analysis. A proof-of-principle study evaluating the effect of HVP on the immune cell function was also undertaken. For the entire patient population, overall hospital survival was 58.7% for patients treated with HVP vs. 47.8% for the control group (hazard ratio (HR), with stratification for liver transplantation: 0.56; 95% confidence interval (CI), 0.36-0.86; p=0.0083). HVP prior to transplantation did not improve survival compared with patients who received SMT alone (CI 0.37 to 3.98; p=0.75). The incidence of severe adverse events was similar in the two groups. Systemic inflammatory response syndrome (SIRS) and sequential organ failure assessment (SOFA) scores fell in the treated group compared to control group, over the study period (pHVP improves outcome in patients with ALF by increasing liver transplant-free survival. This is attributable to attenuation of innate immune activation and amelioration of multi-organ dysfunction. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Productivity Analysis of Volume Fractured Vertical Well Model in Tight Oil Reservoirs
Jiahang Wang
2017-01-01
Full Text Available This paper presents a semianalytical model to simulate the productivity of a volume fractured vertical well in tight oil reservoirs. In the proposed model, the reservoir is a composite system which contains two regions. The inner region is described as formation with finite conductivity hydraulic fracture network and the flow in fracture is assumed to be linear, while the outer region is simulated by the classical Warren-Root model where radial flow is applied. The transient rate is calculated, and flow patterns and characteristic flowing periods caused by volume fractured vertical well are analyzed. Combining the calculated results with actual production data at the decline stage shows a good fitting performance. Finally, the effects of some sensitive parameters on the type curves are also analyzed extensively. The results demonstrate that the effect of fracture length is more obvious than that of fracture conductivity on improving production in tight oil reservoirs. When the length and conductivity of main fracture are constant, the contribution of stimulated reservoir volume (SRV to the cumulative oil production is not obvious. When the SRV is constant, the length of fracture should also be increased so as to improve the fracture penetration and well production.
MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON
The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...
Modeling and control of antennas and telescopes
Gawronski, Wodek
2008-01-01
The book shows, step-by-step, the design, implementation, and testing of the antenna/telescope control system, from the design stage (analytical model) to fine tuning of the RF beam pointing (monopulse and conscan). It includes wide use of Matlab and Simulink..
Advanced feeder control using fast simulation models
Verheijen, O.S.; Op den Camp, O.M.G.C.; Beerkens, R.G.C.; Backx, A.C.P.M.; Huisman, L.; Drummond, C.H.
2005-01-01
For the automatic control of glass quality in glass production, the relation between process variable and product or glass quality and process conditions/process input parameters must be known in detail. So far, detailed 3-D glass melting simulation models were used to predict the effect of process
Plant Modeling for Human Supervisory Control
Lind, Morten
1999-01-01
This paper provides an overview of multilevel flow modelling (MFM) and its application for design of displays for the supervisory control of industrial plant. The problem of designing the inforrrzatian content of sacpervisory displays is discussed and plant representations like MFM using levels...
Power system stability modelling, analysis and control
Sallam, Abdelhay A
2015-01-01
This book provides a comprehensive treatment of the subject from both a physical and mathematical perspective and covers a range of topics including modelling, computation of load flow in the transmission grid, stability analysis under both steady-state and disturbed conditions, and appropriate controls to enhance stability.
Distributed Model Predictive Control via Dual Decomposition
Biegel, Benjamin; Stoustrup, Jakob; Andersen, Palle
2014-01-01
This chapter presents dual decomposition as a means to coordinate a number of subsystems coupled by state and input constraints. Each subsystem is equipped with a local model predictive controller while a centralized entity manages the subsystems via prices associated with the coupling constraints...
Mastenbrook, Matthew J; Commean, Paul K; Hillen, Travis J; Salsich, Gretchen B; Meyer, Gretchen A; Mueller, Michael J; Clohisy, John C; Harris-Hayes, Marcie
2017-12-01
Study Design Secondary analysis, cross-sectional study. Background Chronic hip joint pain (CHJP) can lead to limitations in activity participation, but the musculoskeletal factors associated with the condition are relatively unknown. Understanding the factors associated with CHJP may help develop rehabilitation strategies to improve quality of life of individuals with long-term hip pain. Objectives To compare measures of hip abductor muscle volume and hip abductor muscle strength between women with CHJP and asymptomatic controls. Methods Thirty women, 15 with CHJP and 15 matched asymptomatic controls (age range, 18-40 years), participated in this study. Magnetic resonance imaging was used to determine the volume of the primary hip abductor muscles, consisting of the gluteus medius, gluteus minimus, a small portion of the gluteus maximus, and the tensor fascia latae, within a defined region of interest. Break tests were performed using a handheld dynamometer to assess hip abductor strength. During the strength test, the participant was positioned in sidelying with the involved hip in 15° of abduction. Independent-samples t tests were used to compare muscle volume and strength values between those with CHJP and asymptomatic controls. Results Compared to asymptomatic controls, women with CHJP demonstrated significantly increased gluteal muscle volume (228 ± 40 cm 3 versus 199 ± 29 cm 3 , P = .032), but decreased hip abductor strength (74.6 ± 16.8 Nm versus 93.6 ± 20.2 Nm, P = .009). There were no significant differences in tensor fascia lata muscle volume between the 2 groups (P = .640). Conclusion Women with CHJP appear to have larger gluteal muscle volume, but decreased hip abductor strength, compared to asymptomatic controls. J Orthop Sports Phys Ther 2017;47(12):923-930. Epub 9 Oct 2017. doi:10.2519/jospt.2017.7380.
1984 American Control Conference, San Diego, CA, June 6-8, 1984, Proceedings. Volumes 1, 2 and 3
Anon.
1984-01-01
The topics considered are related to the modeling of human cognitive decision processes, sensor-based robot control systems, adaptive control and applications, modelling and simulation of thermofluid processes and systems, advanced concepts for computer-aided control system design, model reduction and large scale systems, fuel-optimal aircraft guidance and control, and digital signal processing. Other subjects explored are concerned with the dynamical systems approach to problems in nonlinear systems and control, monitoring and fault detection in power systems, robot path planning and control, the real time control of processes, pole placement design, large scale systems and model reduction, and aircraft control. Attention is also given to servomechanisms and machine tool control, stochastic systems, process model-based control and analysis, applications of multivalued logic, microprocessor implementation of real time control systems using high order languages, multitarget tracking, digital systems, filtering and estimation, optimal control, and fault tolerant aerospace systems
Quantum volume and length fluctuations in a midi-superspace model of Minkowski space
Adelman, Jeremy; Hinterleitner, Franz; Major, Seth
2015-01-01
In a (1+1)-dimensional midi-superspace model for gravitational plane waves, a flat space–time condition is imposed with constraints derived from null Killing vectors. Solutions to a straightforward regularization of these constraints have diverging length and volume expectation values. Physically acceptable solutions in the kinematic Hilbert space are obtained from the original constraint by multiplying with a power of the volume operator and by a similar modification of the Hamiltonian constraint, which is used in a regularization of the constraints. The solutions of the modified Killing constraint have finite expectation values of geometric quantities. Further, the expectation value of the original Killing constraint vanishes, but its moment is non-vanishing. As the power of the volume grows, the moment of the original constraint grows, while the moments of volume and length both decrease. Thus, these states provide possible kinematic states for flat space, with fluctuations. As a consequence of the regularization of operators, the quantum uncertainty relations between geometric quantities such as length and its conjugate momentum do not reflect naive expectations from the classical Poisson bracket relations. (paper)
Modeling the Aneuploidy Control of Cancer
Wang Zhong
2010-07-01
Full Text Available Abstract Background Aneuploidy has long been recognized to be associated with cancer. A growing body of evidence suggests that tumorigenesis, the formation of new tumors, can be attributed to some extent to errors occurring at the mitotic checkpoint, a major cell cycle control mechanism that acts to prevent chromosome missegregation. However, so far no statistical model has been available quantify the role aneuploidy plays in determining cancer. Methods We develop a statistical model for testing the association between aneuploidy loci and cancer risk in a genome-wide association study. The model incorporates quantitative genetic principles into a mixture-model framework in which various genetic effects, including additive, dominant, imprinting, and their interactions, are estimated by implementing the EM algorithm. Results Under the new model, a series of hypotheses tests are formulated to explain the pattern of the genetic control of cancer through aneuploid loci. Simulation studies were performed to investigate the statistical behavior of the model. Conclusions The model will provide a tool for estimating the effects of genetic loci on aneuploidy abnormality in genome-wide studies of cancer cells.
Nonsmooth mechanics models, dynamics and control
Brogliato, Bernard
2016-01-01
Now in its third edition, this standard reference is a comprehensive treatment of nonsmooth mechanical systems refocused to give more prominence to control and modelling. It covers Lagrangian and Newton–Euler systems, detailing mathematical tools such as convex analysis and complementarity theory. The ways in which nonsmooth mechanics influence and are influenced by well-posedness analysis, numerical analysis and simulation, modelling and control are explained. Contact/impact laws, stability theory and trajectory-tracking control are given in-depth exposition connected by a framework formed from complementarity systems and measure-differential inclusions. Links are established with electrical circuits with set-valued nonsmooth elements and with other nonsmooth dynamical systems like impulsive and piecewise linear systems. Nonsmooth Mechanics (third edition) has been substantially rewritten, edited and updated to account for the significant body of results that have emerged in the twenty-first century—incl...
Nonlinear model predictive control theory and algorithms
Grüne, Lars
2017-01-01
This book offers readers a thorough and rigorous introduction to nonlinear model predictive control (NMPC) for discrete-time and sampled-data systems. NMPC schemes with and without stabilizing terminal constraints are detailed, and intuitive examples illustrate the performance of different NMPC variants. NMPC is interpreted as an approximation of infinite-horizon optimal control so that important properties like closed-loop stability, inverse optimality and suboptimality can be derived in a uniform manner. These results are complemented by discussions of feasibility and robustness. An introduction to nonlinear optimal control algorithms yields essential insights into how the nonlinear optimization routine—the core of any nonlinear model predictive controller—works. Accompanying software in MATLAB® and C++ (downloadable from extras.springer.com/), together with an explanatory appendix in the book itself, enables readers to perform computer experiments exploring the possibilities and limitations of NMPC. T...
Nemschokmichal, Sebastian; Tschiersch, Robert; Höft, Hans; Wild, Robert; Bogaczyk, Marc; Becker, Markus M.; Loffhagen, Detlef; Stollenwerk, Lars; Kettlitz, Manfred; Brandenburg, Ronny; Meichsner, Jürgen
2018-05-01
The phenomenology and breakdown mechanism of dielectric barrier discharges are strongly determined by volume and surface memory effects. In particular, the pre-ionization provided by residual species in the volume or surface charges on the dielectrics influences the breakdown behavior of filamentary and diffuse discharges. This was investigated by advanced diagnostics such as streak camera imaging, laser photodetachment of negative ions and laser photodesorption of electrons from dielectric surfaces in correlation with 1D fluid modeling. The streak camera images show that an increasing number of residual charges in the volume changes the microdischarge breakdown in air-like gas mixtures from a cathode-directed streamer to a simultaneous propagation of cathode- and anode-directed streamers. In contrast, seed electrons are important for the pre-ionization if the density of residual charges in the volume is low. One source of seed electrons are negative ions, whose density exceeds the electron density during the pre-phase of diffuse helium-oxygen barrier discharges as indicated by the laser photodetachment experiments. Electrons desorbed from the cathodic dielectric have an even larger influence. They induce a transition from the glow-like to the Townsend-like discharge mode in nominally pure helium. Apart from analyzing the importance of the pre-ionization for the breakdown mechanism, the opportunities for manipulating the lateral structure and discharge modes are discussed. For this purpose, the intensity and diameter of a diffuse discharge in helium are controlled by an illuminated semiconducting barrier. Contribution to the Topical Issue "Fundamentals of Complex Plasmas", edited by Jürgen Meichsner, Michael Bonitz, Holger Fehske, Alexander Piel.
Investigation of tDCS volume conduction effects in a highly realistic head model
Wagner, S.; Rampersad, S. M.; Aydin, Ü.; Vorwerk, J.; Oostendorp, T. F.; Neuling, T.; Herrmann, C. S.; Stegeman, D. F.; Wolters, C. H.
2014-02-01
Objective. We investigate volume conduction effects in transcranial direct current stimulation (tDCS) and present a guideline for efficient and yet accurate volume conductor modeling in tDCS using our newly-developed finite element (FE) approach. Approach. We developed a new, accurate and fast isoparametric FE approach for high-resolution geometry-adapted hexahedral meshes and tissue anisotropy. To attain a deeper insight into tDCS, we performed computer simulations, starting with a homogenized three-compartment head model and extending this step by step to a six-compartment anisotropic model. Main results. We are able to demonstrate important tDCS effects. First, we find channeling effects of the skin, the skull spongiosa and the cerebrospinal fluid compartments. Second, current vectors tend to be oriented towards the closest higher conducting region. Third, anisotropic WM conductivity causes current flow in directions more parallel to the WM fiber tracts. Fourth, the highest cortical current magnitudes are not only found close to the stimulation sites. Fifth, the median brain current density decreases with increasing distance from the electrodes. Significance. Our results allow us to formulate a guideline for volume conductor modeling in tDCS. We recommend to accurately model the major tissues between the stimulating electrodes and the target areas, while for efficient yet accurate modeling, an exact representation of other tissues is less important. Because for the low-frequency regime in electrophysiology the quasi-static approach is justified, our results should also be valid for at least low-frequency (e.g., below 100 Hz) transcranial alternating current stimulation.
A finite volume alternate direction implicit approach to modeling selective laser melting
Hattel, Jesper Henri; Mohanty, Sankhya
2013-01-01
Over the last decade, several studies have attempted to develop thermal models for analyzing the selective laser melting process with a vision to predict thermal stresses, microstructures and resulting mechanical properties of manufactured products. While a holistic model addressing all involved...... to accurately simulate the process, are constrained by either the size or scale of the model domain. A second challenging aspect involves the inclusion of non-linear material behavior into the 3D implicit FE models. An alternating direction implicit (ADI) method based on a finite volume (FV) formulation...... is proposed for modeling single-layer and few-layers selective laser melting processes. The ADI technique is implemented and applied for two cases involving constant material properties and non-linear material behavior. The ADI FV method consume less time while having comparable accuracy with respect to 3D...
MODELLING OF DYNAMIC SPEED LIMITS USING THE MODEL PREDICTIVE CONTROL
Andrey Borisovich Nikolaev
2017-09-01
Full Text Available The article considers the issues of traffic management using intelligent system “Car-Road” (IVHS, which consist of interacting intelligent vehicles (IV and intelligent roadside controllers. Vehicles are organized in convoy with small distances between them. All vehicles are assumed to be fully automated (throttle control, braking, steering. Proposed approaches for determining speed limits for traffic cars on the motorway using a model predictive control (MPC. The article proposes an approach to dynamic speed limit to minimize the downtime of vehicles in traffic.
Nonlinear Model Predictive Control for Cooperative Control and Estimation
Ru, Pengkai
Recent advances in computational power have made it possible to do expensive online computations for control systems. It is becoming more realistic to perform computationally intensive optimization schemes online on systems that are not intrinsically stable and/or have very small time constants. Being one of the most important optimization based control approaches, model predictive control (MPC) has attracted a lot of interest from the research community due to its natural ability to incorporate constraints into its control formulation. Linear MPC has been well researched and its stability can be guaranteed in the majority of its application scenarios. However, one issue that still remains with linear MPC is that it completely ignores the system's inherent nonlinearities thus giving a sub-optimal solution. On the other hand, if achievable, nonlinear MPC, would naturally yield a globally optimal solution and take into account all the innate nonlinear characteristics. While an exact solution to a nonlinear MPC problem remains extremely computationally intensive, if not impossible, one might wonder if there is a middle ground between the two. We tried to strike a balance in this dissertation by employing a state representation technique, namely, the state dependent coefficient (SDC) representation. This new technique would render an improved performance in terms of optimality compared to linear MPC while still keeping the problem tractable. In fact, the computational power required is bounded only by a constant factor of the completely linearized MPC. The purpose of this research is to provide a theoretical framework for the design of a specific kind of nonlinear MPC controller and its extension into a general cooperative scheme. The controller is designed and implemented on quadcopter systems.
Nadimi, Esmaeil Sharak; Bak, Thomas; Izadi-Zamanabadi, Roozbeh
2006-01-01
The main objective of this paper is to investigate the erformance and applicability of two GPC (generalized predictive control) based control methods on a complete benchmark model of the Stewart platform made in MATLAB V6.5. The first method involves an LQG controller (Linear Quadratic Gaussian...