Architectural Specialization for Inter-Iteration Loop Dependence Patterns

This paper presents a new method to design (or analyze) subsonic or supersonic axial compressor and turbine stages and their three-dimensional velocity diagrams from hub to tip by solving the three-dimensional radial-momentum equation. Some previous methods (matrix through-flow based on the streamfunction approach) can not handle locally supersonic flows, and they are computationally intensive when they require the inversion of large matrices. Other previous methods (streamline curvature) require two nested iteration loops to provide a converged solution: an outside iteration loop for the mass-flow balance; and an inside iteration loop to solve the radial momentum equation at each flow station. The present method is of the streamline-curvature category. It still requires the iteration loop for the mass-flow balance, but the radial momentum equation at each flow station is solved using a one-pass numerical predictor-corrector technique, thus reducing the computational effort substantially. The method takes into account the axial slope of the streamlines. Main design characteristics such as the mass-flow rate, total properties at component inlet, hub-to-tip ratio at component inlet, total enthalpy change for each stage, and the expected efficiency of each streamline at each stage are inputs to the method. Other inputs are the radial position and axial velocity component at one surface of revolution through the axial stages. These can be provided for either the hub, or the mean, or the tip location of the blading. In addition the user specifies the azimuthal deflection of the flow from the axial direction at each radius (or as a function of radius) at each blade row inlet and outlet. By construction the method eliminates radial variations of total enthalpy (work) and entropy at each blade row inlet and outlet. In an alternative formulation enthalpy variations across radial positions at each axial station are included in the analysis. The remaining three-dimensional velocity diagrams from hub to tip, and the radial location of the remaining streamlines, are obtained by solving the momentum equation using a predictor-corrector method. Examples for one turbine and one compressor design are included.

Pseudo-Inverse Based Iterative Learning Control for Linear Nonminimum Phase Plants with Unmodeled Dynamics*

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.1789540 ◽

2004 ◽

Vol 126 (3) ◽

pp. 661-665 ◽

Cited By ~ 8

Author(s):

Jayati Ghosh ◽

Brad Paden

Keyword(s):

Iterative Learning Control ◽

Low Frequency ◽

Learning Control ◽

Iterative Learning ◽

Nonminimum Phase ◽

Low Pass ◽

Frequency Components ◽

Iteration Loop ◽

Plant Uncertainty ◽

Pseudo Inverse

Learning control is a very effective approach for tracking repetitive processes. In this paper, the stable-inversion based learning controller as presented in (Ghosh, J. and Paden, B., 1999, “Iterative Learning Control for Nonlinear Nonminimum Phase Plants with Input Disturbances,” in Proc. of American Control Conference; Ghosh, J. and Paden, B., 1999, “A pseudo-inverse based Iterative Learning Control for Nonlinear Plants with Disturbances,” in Proc. of 38th Conference on Decision and Control.) is modified to accommodate linear nonminimum phase plants with uncertainties. The design of the learning controller is based on the computation of an approximate inverse of the nominal model of the linear plant, rather than its exact inverse. The advantages of this approach are that the output of the plant need not be differentiated and also the plant model need not be exact. A low pass zero-phase filter is used in the iteration loop to achieve robustness to plant uncertainty. The structure of the controller is such that the low frequency components of the trajectory converge faster than the high frequency components.

Total Sustainability Management. Describing the Conditions, Requirements and Application of Sustainability Management

Management Systems in Production Engineering ◽

10.1515/mspe-2019-0019 ◽

2019 ◽

Vol 27 (2) ◽

pp. 110-118 ◽

Cited By ~ 1

Author(s):

Stefan Boroń ◽

Tomasz Kosiek

Keyword(s):

Sustainable Development ◽

Current Development ◽

Practical Application ◽

Management Effectiveness ◽

System Framework ◽

Sustainability Management ◽

Trade Off ◽

Key Concepts ◽

Development Processes ◽

Iteration Loop

Abstract Countless people and organisations have been wrestling with the practical application of sustainability and sustainable development. Yet there is no rigorous and unequivocal template that can be followed for management because the meaning of the key concepts of sustainability and development in particular haven’t been properly identified. Although the fundamental meaning of the word sustainability is continuance, the concept has its controversies especially when it drifts into the ‘abstract’ and even becomes confused with sustainable development. For our purposes it is the ability of development and of its associated processing activities to continue that is being managed. For management effectiveness, a system framework is necessary but more importantly what goes into that system has to be rigorously and unambiguously defined. In our case, the mechanisms describing the practicalities that govern the sustainability of development have been clearly identified in this paper and called by name. The concept of development needs clarification, while the accepted popular ‘three pillar’ depiction of sustainable development is also fundamentally flawed when compared with the form of words of the ‘Brundtland’ definition. This well-known ‘Venn representation’ implies a type of ‘balance’ or ‘synergy’ at the heart of sustainability management. In fact, because of the fundamentally unsustainable nature of current development processes, the ‘balance’ turns into a trade-off amongst the three sustainability players. For real sustainable development there can be no such trade-off. Once the misunderstandings are clarified the true basics of sustainability and sustainable development are fed into a standard ISO14001 iteration loop for management to commence.

A New High-Precision Correction Method of Temperature Distribution in Model Stellar Atmospheres

Open Astronomy ◽

10.1515/astro-2017-0154 ◽

2013 ◽

Vol 22 (2) ◽

Author(s):

A. Sapar ◽

R. Poolamäe ◽

L. Sapar

Keyword(s):

Temperature Distribution ◽

High Precision ◽

Linear Optimization ◽

Correction Method ◽

Stellar Model ◽

Temperature Correction ◽

Stellar Atmospheres ◽

Local Source ◽

Plane Parallel ◽

Iteration Loop

AbstractThe main features of the temperature correction methods, suggested and used in modeling of plane-parallel stellar atmospheres, are discussed. The main features of the new method are described. Derivation of the formulae for a version of the Unsöld-Lucy method, used by us in the SMART (Stellar Model Atmospheres and Radiative Transport) software for modeling stellar atmospheres, is presented. The method is based on a correction of the model temperature distribution based on minimizing differences of flux from its accepted constant value and on the requirement of the lack of its gradient, meaning that local source and sink terms of radiation must be equal. The final relative flux constancy obtainable by the method with the SMART code turned out to have the precision of the order of 0.5 %. Some of the rapidly converging iteration steps can be useful before starting the high-precision model correction. The corrections of both the flux value and of its gradient, like in Unsöld-Lucy method, are unavoidably needed to obtain high-precision flux constancy. A new temperature correction method to obtain high-precision flux constancy for plane-parallel LTE model stellar atmospheres is proposed and studied. The non-linear optimization is carried out by the least squares, in which the Levenberg-Marquardt correction method and thereafter additional correction by the Broyden iteration loop were applied. Small finite differences of temperature (

Iterative Text-Based Editing of Talking-Heads Using Neural Retargeting

ACM Transactions on Graphics ◽

10.1145/3449063 ◽

2021 ◽

Vol 40 (3) ◽

pp. 1-14

Author(s):

Xinwei Yao ◽

Ohad Fried ◽

Kayvon Fatahalian ◽

Maneesh Agrawala

Keyword(s):

Real World ◽

Search Algorithm ◽

Performance Style ◽

Talking Head ◽

Talking Heads ◽

Overall Performance ◽

And Performance ◽

Iteration Loop ◽

Loop 2 ◽

Fine Tune

We present a text-based tool for editing talking-head video that enables an iterative editing workflow. On each iteration users can edit the wording of the speech, further refine mouth motions if necessary to reduce artifacts, and manipulate non-verbal aspects of the performance by inserting mouth gestures (e.g., a smile) or changing the overall performance style (e.g., energetic, mumble). Our tool requires only 2 to 3 minutes of the target actor video and it synthesizes the video for each iteration in about 40 seconds, allowing users to quickly explore many editing possibilities as they iterate. Our approach is based on two key ideas. (1) We develop a fast phoneme search algorithm that can quickly identify phoneme-level subsequences of the source repository video that best match a desired edit. This enables our fast iteration loop. (2) We leverage a large repository of video of a source actor and develop a new self-supervised neural retargeting technique for transferring the mouth motions of the source actor to the target actor. This allows us to work with relatively short target actor videos, making our approach applicable in many real-world editing scenarios. Finally, our, refinement and performance controls give users the ability to further fine-tune the synthesized results.

An improved iteration loop for the three dimensional quasi-static particle-in-cell algorithm: QuickPIC

Journal of Computational Physics ◽

10.1016/j.jcp.2013.05.020 ◽

2013 ◽

Vol 250 ◽

pp. 165-177 ◽

Cited By ~ 31

Author(s):

Weiming An ◽

Viktor K. Decyk ◽

Warren B. Mori ◽

Thomas M. Antonsen

Keyword(s):

Three Dimensional ◽

Particle In Cell ◽

Iteration Loop

Direct measurement of dT/dΔ

Bulletin of the Seismological Society of America ◽

10.1785/bssa0590020717 ◽

1969 ◽

Vol 59 (2) ◽

pp. 717-727

Author(s):

E. S. Husebye

Keyword(s):

Direct Measurement ◽

Least Square Method ◽

Least Square ◽

Wave Parameter ◽

Standard Errors ◽

Random Errors ◽

Arrival Times ◽

True Value ◽

Using Data ◽

Iteration Loop

abstract In this paper we describe and demonstrate a least square method for direct measurement of the wave parameter dT/dΔ. The information necessary for doing this is the coordinates of arbitrarily spaced seismic stations and relative arrival times of the phase under investigation. The dT/dΔ parameter is derived from a function in ϕ and λ, representing the variation of T over the array. An iteration loop is included for examining and selecting a T-response function of simple form, i.e., containing few parameters, and thus making the method applicable even to arrays containing few stations. Using data from Jeffreys-Bullen tables where sometimes random errors are added, the calculated dT/dΔ values at the array centers deviate less than 0.06 from the true value and the estimates have standard errors around ±0.15.

The Complex Approach of the C-lightVer System to the Automated Error Localization in C-programs

Modeling and Analysis of Information Systems ◽

10.18255/1818-1015-2019-4-502-519 ◽

2019 ◽

Vol 26 (4) ◽

pp. 502-519

Author(s):

Dmitry A. Kondratyev ◽

Alexei V. Promsky

Keyword(s):

The Body ◽

Theorem Prover ◽

Input Language ◽

Symbolic Form ◽

C Programs ◽

Complex Approach ◽

Execution Condition ◽

Iteration Loop ◽

Semantic Markup ◽

Replacement Operation

The C-lightVer system for the deductive verification of C programs is being developed at the IIS SB RAS. Based on the two-level architecture of the system, the C-light input language is translated into the intermediate C-kernel language. The meta generator of the correctness conditions receives the C-kernel program and Hoare logic for the C-kernel as input. To solve the well-known problem of determining loop invariants, the definite iteration approach was chosen. The body of the definite iteration loop is executed once for each element of the finite dimensional data structure, and the inference rule for them uses the substitution operation rep, which represents the action of the cycle in symbolic form. Also, in our meta generator, the method of semantic markup of correctness conditions has been implemented and expanded. It allows to generate explanations for unproven conditions and simplifies the errors localization. Finally, if the theorem prover fails to determine the truth of the condition, we can focus on proving its falsity. Thus a method of proving the falsity of the correctness conditions in the ACL2 system was developed. The need for more detailed explanations of the correctness conditions containing the replacement operation rep has led to a change of the algorithms for generating the replacement operation, and the generation of explanations for unproven correctness conditions. Modifications of these algorithms are presented in the article. They allow marking rep definition with semantic labels, extracting semantic labels from rep definition and generating description of break execution condition.

Development of a Process Oriented Calibration Scheme for the HBV Hydrological Model

Hydrology Research ◽

10.2166/nh.1991.0002 ◽

1991 ◽

Vol 22 (1) ◽

pp. 15-36 ◽

Cited By ~ 51

Author(s):

Joakim Harlin

Keyword(s):

Hydrological Model ◽

Optimal Parameter ◽

Model Performance ◽

Computer Time ◽

Fine Tuning ◽

Parameter Estimates ◽

Calibration Period ◽

Calibration Scheme ◽

Process Oriented ◽

Iteration Loop

A process oriented calibration scheme (POC), developed for the HBV hydrological model is presented. Twelve parameters were calibrated in two steps. Firstly, initial parameter estimates were made from recession analysis of observed runoff. Secondly, the parameters were calibrated individually in an iteration loop starting with the snow routine, over the soil routine and finally the runoff-response function. This was done by minimizing different objective functions for different parameters and only over subperiods where the parameters were active. Approximately three hundred and fifty objective function evaluations were needed to find the optimal parameter set, which resulted in a computer time of about 17 hours on a 386 processor PC for a ten-year calibration period. Experiments were also performed with fine tuning as well as direct search of the response surface, where the parameters were allowed to change simultaneously. A calibration period length of between two and six years was found sufficient to find optimal parameters in the test basins. The POC scheme yielded as good model performance as after a manual calibration.

Analytical modeling of disc-type permanent magnet hysteresis motor in steady-state operational conditions

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-07-2016-0315 ◽

2017 ◽

Vol 36 (4) ◽

pp. 991-1007

Author(s):

Ali Behniafar ◽

Ahmad Darabi

Keyword(s):

Permanent Magnet ◽

Performance Prediction ◽

Analytical Method ◽

Input Voltage ◽

Permanent Magnet Motors ◽

Content Type ◽

Operational Conditions ◽

Faraday’S Law ◽

Mathematical Equations ◽

Iteration Loop

Purpose In this paper, a new structure for the permanent magnet hysteresis synchronous (PMHS) motor is introduced. Moreover, this paper aims to presents a new analytical method for modeling of a disc-type PMHS motor. Design/methodology/approach Because the hysteresis and permanent magnet motors have unique characteristics, a motor (the PMHS motor) with excellent performance features can be achieved by combining them. Choosing a disc-type slotless structure causes the major advantages of both motors to be preserved in the new motor. To analyze PMHS motor, mathematical equations are obtained by using Ampere’s circuital law, flux continuity law and Faraday’s law. Then the air-gap voltage and exciting current of the motor can be calculated. To implement this method, a new iterative algorithm is proposed. This algorithm consists of one-iteration loop for each input voltage to find the maximum flux density of the operational hysteresis loop of the motor. Findings Validity of the analytical approach is confirmed by experimental results. A reasonably close agreement between the two is shown and some outstanding performances of the PMHS motor are demonstrated. Originality/value A new structure for PMHS motor and also a new analytical method for performance prediction of this motor is presented.