Log in

Relevant bibliographies by topics / Non-Stationary conditions / Journal articles

To see the other types of publications on this topic, follow the link: Non-Stationary conditions.

Journal articles on the topic 'Non-Stationary conditions'

Author: Grafiati

Published: 5 April 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Non-Stationary conditions.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Abu el Ata-Doss, S., and P. Ponty. "Supervision of Controlled Processes in Non-Stationary Conditions." IFAC Proceedings Volumes 18, no. 5 (July 1985): 351–56. http://dx.doi.org/10.1016/s1474-6670(17)60584-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Verhoeven, Marijn J. M., and Harrie A. A. Verbon. "Expectations on pension schemes under non-stationary conditions." Economics Letters 36, no. 1 (May 1991): 99–103. http://dx.doi.org/10.1016/0165-1765(91)90063-q.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Čiegis, Raimondas, Olga Štikonienė, and Olga Suboč. "On one problem with non-local boundary conditions." Lietuvos matematikos rinkinys 41 (December 17, 2001): 497–503. http://dx.doi.org/10.15388/lmr.2001.34636.

Full text

Abstract:

In this article two problems with non-local boundary conditions are analysed: stationary diffusion problem with constant coeficients and non-local boundary condition, and stationary diffusion problem with additional convection term and non-local boundary condition. Finite difference schemes are constructed and investigated. The sufficient conditions for the existence of an unique solution are obtained.

APA, Harvard, Vancouver, ISO, and other styles

4

Vogel, Richard M., and Charles N. Kroll. "A comparison of estimators of the conditional mean under non-stationary conditions." Advances in Water Resources 143 (September 2020): 103672. http://dx.doi.org/10.1016/j.advwatres.2020.103672.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Ganguli, Rajive, and Jon C. Yingling. "Algorithms to control coal segregation under non-stationary conditions." International Journal of Mineral Processing 61, no. 4 (April 2001): 261–71. http://dx.doi.org/10.1016/s0301-7516(00)00063-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Ganguli, Rajive, and Jon C. Yingling. "Algorithms to control coal segregation under non-stationary conditions." International Journal of Mineral Processing 61, no. 4 (April 2001): 241–59. http://dx.doi.org/10.1016/s0301-7516(00)00064-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Murari, A., M. Lungaroni, M. Gelfusa, E. Peluso, and J. Vega. "Adaptive learning for disruption prediction in non-stationary conditions." Nuclear Fusion 59, no. 8 (July 4, 2019): 086037. http://dx.doi.org/10.1088/1741-4326/ab1ecc.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Aliyev, A. M., A. R. Safarov, I. V. Balayev, I. I. Osmanova, A. M. Guseynova, and F. G. Bayramov. "DEVELOPMENT OF A NON-STATIONARY MATHEMATICAL MODEL FOR THE PROCESS OF POLYMERIZATION OF PROPYLENE." Azerbaijan Chemical Journal, no. 4 (December 12, 2020): 6–11. http://dx.doi.org/10.32737/0005-2531-2020-4-6-11.

Full text

Abstract:

The mathematical model has been developed for the process polymerization propylene proceeding under unsteady conditions due to the toxic effect of methylacetylene on it, leading to decrease of the productivity and quality of polypropylene. Non-stationary function to maintain the productivity at the optimum level obtained during the process in stationary conditions has been proposed. Using this mathematical model allow ones control the process, stabilize it at any time of the polymerization operation. The control scheme of algorithm of this process has been created

APA, Harvard, Vancouver, ISO, and other styles

9

Kukačka, Leoš, Jan Kraus, Milan Kolář, Pascal Dupuis, and Georges Zissis. "Review of AC power theories under stationary and non-stationary, clean and distorted conditions." IET Generation, Transmission & Distribution 10, no. 1 (January 7, 2016): 221–31. http://dx.doi.org/10.1049/iet-gtd.2015.0713.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Himani and Ratna Dahiya. "Condition monitoring of wind turbine for rotor fault detection under non stationary conditions." Ain Shams Engineering Journal 9, no. 4 (December 2018): 2441–52. http://dx.doi.org/10.1016/j.asej.2017.04.002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

DMITRIENKO, I. S. "Nonlinear non-stationary Alfvén resonance." Journal of Plasma Physics 62, no. 2 (August 1999): 145–64. http://dx.doi.org/10.1017/s0022377899007758.

Full text

Abstract:

For a cold plasma that is inhomogeneous (in the direction across an external homogeneous magnetic field), the nonlinear equation describing the spatial structure and temporal behaviour of a non-stationary disturbance in a resonance layer is obtained. The matching conditions for a disturbance through the resonance layer are obtained, and in the linear limit give a well-known linear matching. It is shown that the spatial and temporal behaviour of the resonance disturbance and the evolution of the resonant absorption in terms of nonlinear theory are determined by the ratio of the nonlinear to linear non-stationary spatial scales. The spatial–temporal profile of the disturbance in the resonance layer and the resonant absorption for different values of this ratio are calculated. A nonlinear decrease in the resonant absorption and a stratification of the resonance disturbance are revealed.

APA, Harvard, Vancouver, ISO, and other styles

12

Mashava, Destine, James Kuria Kimotho, and Onesmus Mutuku Muvengei. "Gearbox Multiple Faults Diagnosis under Stationary and Non-Stationary Operating Conditions Using Convolutional Neural Networks." Engineering Advances 2, no. 1 (January 7, 2022): 1–17. http://dx.doi.org/10.26855/ea.2022.06.001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

June, Wolfgang, and Andrea Polle. "Theory of proton flow along appressed thylakoid membranes under both non-stationary and stationary conditions." Biochimica et Biophysica Acta (BBA) - Bioenergetics 848, no. 3 (March 1986): 265–73. http://dx.doi.org/10.1016/0005-2728(86)90200-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Cherniak, Gil, Jonathan Nemirovsky, Amikam Nemirovsky, and Yael Nemirovsky. "Modeling Signal-to-Noise Ratio of CMOS Image Sensors with a Stochastic Approach under Non-Stationary Conditions." Sensors 23, no. 17 (August 23, 2023): 7344. http://dx.doi.org/10.3390/s23177344.

Full text

Abstract:

A stochastic model for characterizing the conversion gain of Active Pixel Complementary metal–oxide–semiconductor (CMOS) image sensors (APS), assuming stationary conditions was recently presented in this journal. In this study, we extend the stochastic approach to non-stationary conditions. Non-stationary conditions occur in gated imaging applications. This new stochastic model, which is based on fundamental physical considerations, enlightens us with new insights into gated CMOS imaging, regardless of the sensor. The Signal-to-Noise Ratio (SNR) is simulated, allowing optimized performance. The conversion gain should be determined under stationary conditions.

APA, Harvard, Vancouver, ISO, and other styles

15

Pakdel, Hadis, Dev Raj Paudyal, Sreeni Chadalavada, Md Jahangir Alam, and Majid Vazifedoust. "A Multi-Framework of Google Earth Engine and GEV for Spatial Analysis of Extremes in Non-Stationary Condition in Southeast Queensland, Australia." ISPRS International Journal of Geo-Information 12, no. 9 (September 6, 2023): 370. http://dx.doi.org/10.3390/ijgi12090370.

Full text

Abstract:

The frequency and severity of extremes, including extreme precipitation events, extreme evapotranspiration and extreme water storage deficit events, are changing. Thus, the necessity for developing a framework that estimates non-stationary conditions is urgent. The aim of this paper is to develop a framework using the geeSEBAL platform, Generalised Extreme Value (GEV) models and spatiotemporal analysis techniques that incorporate the physical system in terms of cause and effect. Firstly, the geeSEBAL platform has enabled the estimation of actual evapotranspiration (ETa) with an unprecedented level of spatial-temporal resolution. Following this, the Non-stationary Extreme Value Analysis (NEVA) approach employs the Bayesian method using a Differential Evolution Markov Chain technique to calculate the frequency and magnitude of extreme values across the parameter space. Station and global climate datasets have been used to analyse the spatial and temporal variation of rainfall, reference evapotranspiration (ETo), ETa and water storage (WS) variables in the Lockyer Valley located in Southeast Queensland (SEQ), Australia. Frequency analysis of rainfall, ETa, and water storage deficit for 14 stations were performed using a GEV distribution under stationary and non-stationary assumptions. Comparing the ETa, ETo and ERA5 rainfall with station data showed reasonable agreement as follows: Pearson correlation of 0.59–0.75 for ETa, RMSE of 45.23–58.56 mm for ETa, Pearson correlation of 0.96–0.97 for ETo, RMSE of 73.13–87.73 mm for ETo and Pearson correlation of 0.87–0.92 for rainfall and RMSE of 37.53–57.10 mm for rainfall. The lower and upper uncertainty bounds between stationary and non-stationary conditions for rainfall station data of Gatton varied from 550.98 mm (stationary) to 624.97 mm (non-stationary), and for ERA5 rainfall datasets, 441.30 mm (stationary) to 450.77 mm (non-stationary). The results demonstrate that global climate datasets underestimate the difference between stationary and non-stationary conditions by 9.47 mm compared to results of 73.99 mm derived from station data. Similarly, the results demonstrate less variation between stationary and non-stationary conditions in water storage, followed by a sharp variation in rainfall and moderate variation in evapotranspiration. The findings of this study indicate that neglecting the non-stationary condition in some hydrometeorological variables can lead to underestimating their amounts. This framework can be applied to any geographical area for estimating extreme conditions, providing valuable insights for infrastructure planning and design, risk assessment and disaster management.

APA, Harvard, Vancouver, ISO, and other styles

16

Kopeitsev, Viktor N., Mikhael E. Romash, and Aleksei Y. Varaksin. "Tornado-like non-stationary vortices: experimental modelling under laboratory conditions." Natural Science 03, no. 11 (2011): 907–13. http://dx.doi.org/10.4236/ns.2011.311116.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Belous, A. N., G. A. Kotov, D. A. Sapronov, and B. A. Novikov. "DETERMINATION OF HEAT TRANSFER RESISTANCE IN NON-STATIONARY THERMAL CONDITIONS." Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel'nogo universiteta. JOURNAL of Construction and Architecture 22, no. 6 (December 29, 2020): 83–93. http://dx.doi.org/10.31675/1607-1859-2020-22-6-83-93.

Full text

Abstract:

One of the main normalized heat engineering indicators of enclosing structures is the resistance to heat transfer. On the territory of the CIS countries there are a huge number of real estate objects designed and built in accordance with outdated standards for the consumption of heat energy for heating and ventilation, requirements for the heat-protective shell of buildings, which leads to energy overspending. All real estate objects put into operation before the tightening of the above-mentioned standards require determining the actual thermal characteristics of the enclosing structures and bringing them into compliance with the current legislation. The article analyzes existing methods for determining the heat transfer resistance of enclosing structures in full-scale conditions, and identifies the advantages and disadvantages of these methods. Based on the fundamental research of construction Thermophysics, a mathematical model for determining the resistance to heat transfer in full-scale conditions is proposed, taking into account the shortcomings of existing methods.

APA, Harvard, Vancouver, ISO, and other styles

18

Martinsson, J. "Compensating distortion effects in repeated measurements under non-stationary conditions." Measurement Science and Technology 20, no. 2 (December 17, 2008): 025103. http://dx.doi.org/10.1088/0957-0233/20/2/025103.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Diez-Ibarbia, A., A. Fernandez-del-Rincon, P. Garcia, and F. Viadero. "Gear rattle dynamics under non-stationary conditions: The lubricant role." Mechanism and Machine Theory 151 (September 2020): 103929. http://dx.doi.org/10.1016/j.mechmachtheory.2020.103929.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Varaksin, A. Y. "Modeling air and fire non-stationary whirls in laboratory conditions." Journal of Physics: Conference Series 980 (March 2018): 012019. http://dx.doi.org/10.1088/1742-6596/980/1/012019.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Rosero García, Javier, José Luis Romeral, and Esteban Rosero García. "Detecting eccentricity faults in a PMSM in non-stationary conditions." Ingeniería e Investigación 32, no. 1 (January 1, 2012): 5–10. http://dx.doi.org/10.15446/ing.investig.v32n1.28512.

Full text

Abstract:

Permanent magnet alternating current machines are being widely used in applications demanding high and rugged performance, such as industrial automation and the aerospace and automotive industries. This paper presents a study of a permanent magnet synchronous machine (PMSM) running in eccentricity; these machines' condition monitoring and fault detection would provide added value and they are also assuming growing importance. This paper investigates the effect of eccentricity faults on PMSM motors' current spectrum with a view to developing an effective condition-monitoring scheme using two-dimensional (2-D) finite element analysis (FEA). Stator current induced harmonics were investigated for fault conditions and advanced signal analysis involved continuous and discrete wavelet transforms. Simulation and experimental results are presented to substantiate that the proposed method worked over a wide speed range for motor operation and that it provided an effective tool for diagnosing PMSM operating condition.

APA, Harvard, Vancouver, ISO, and other styles

22

Silvestrini, Paolo. "Temperature dependence of macroscopic quantum effects in non-stationary conditions." Physics Letters A 152, no. 5-6 (January 1991): 306–10. http://dx.doi.org/10.1016/0375-9601(91)90112-l.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Mo, Chongxun, Changhao Jiang, Xingbi Lei, Weiyan Cen, Zhiwei Yan, Gang Tang, Lingguang Li, Guikai Sun, and Zhenxiang Xing. "Optimal Scheduling of Reservoir Flood Control under Non-Stationary Conditions." Sustainability 15, no. 15 (July 25, 2023): 11530. http://dx.doi.org/10.3390/su151511530.

Full text

Abstract:

To improve reservoir flood control and scheduling schemes under changing environmental conditions, we established an adaptive reservoir regulation method integrating hydrological non-stationarity diagnosis, hydrological frequency analysis, design flood calculations, and reservoir flood control optimization scheduling and applied it to the Chengbi River Reservoir. The results showed that the peak annual flood sequence and the variation point of the annual maximum 3-day flood sequence of the Chengbi River Reservoir was in 1979, and the variation point of the annual maximum 1-day flood sequence was in 1980. A mixed distribution model was developed via a simulated annealing algorithm, hydrological frequency analysis was carried out, and a non-stationary design flood considering the variation point was obtained according to the analysis results; the increases in the flood peak compared to the original design were 4.00% and 8.66%, respectively. A maximum peak reduction model for optimal reservoir scheduling using the minimum sum of squares of the downgradient flow as the objective function was established and solved via a particle swarm optimization algorithm. The proposed adaptive scheduling scheme reduced discharge flow to 2661 m3/s under 1000-year flood conditions, and the peak reduction rate reached 60.6%. Furthermore, the discharge flow was reduced to 2661 m3/s under 10,000-year flood conditions, and the peak reduction rate reached 65.9%.

APA, Harvard, Vancouver, ISO, and other styles

24

Ustinov, A. I., M. V. Kulinich, and S. G. Kosintsev. "Influence of thermal contacts on heating aluminium plates under non-stationary heating conditions, using the SHS-process." Paton Welding Journal 2023, no. 10 (October 28, 2023): 18–23. http://dx.doi.org/10.37434/tpwj2023.10.03.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Bartelmus, W., and R. Zimroz. "A new feature for monitoring the condition of gearboxes in non-stationary operating conditions." Mechanical Systems and Signal Processing 23, no. 5 (July 2009): 1528–34. http://dx.doi.org/10.1016/j.ymssp.2009.01.014.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Čiegis, R., A. Štikonas, O. Štikoniene, and O. Suboč. "STATIONARY PROBLEMS WITH NONLOCAL BOUNDARY CONDITIONS." Mathematical Modelling and Analysis 6, no. 2 (December 15, 2001): 178–91. http://dx.doi.org/10.3846/13926292.2001.9637157.

Full text

Abstract:

In this article a stationary problems with general nonlocal boundary conditions is considered. The differential problems and finite difference schemes for solving this problem are investigated. Stability estimates are proved in the maximum norm and the non‐negativity of the solution is investigated. All theoretical results are illustrated by representative examples.

APA, Harvard, Vancouver, ISO, and other styles

27

Lodetti, Stefano, Jorge Bruna, Julio J. Melero, and José F. Sanz. "Wavelet Packet Decomposition for IEC Compliant Assessment of Harmonics under Stationary and Fluctuating Conditions." Energies 12, no. 22 (November 19, 2019): 4389. http://dx.doi.org/10.3390/en12224389.

Full text

Abstract:

This paper presents the validation and characterization of a wavelet based decomposition method for the assessment of harmonic distortion in power systems, under stationary and non-stationary conditions. It uses Wavelet Packet Decomposition with Butterworth Infinite Impulse Response filters and a decomposition structure, which allows the measurement of both odd and even harmonics, up to the 63rd order, fully compliant with the requirements of the IEC 61000-4-7 standard. The method is shown to fulfil the IEC accuracy requirements for stationary harmonics, obtaining the same accuracy even under fluctuating conditions. Then, it is validated using simulated signals with real harmonic content. The proposed method is proven to be fully equivalent to Fourier analysis under stationary conditions, being often more accurate. Under non-stationary conditions, instead, it provides significantly higher accuracy, while the IEC strategy produces large errors. Lastly, the method is tested with real current and voltage signals, measured in conditions of high harmonic distortion. The proposed strategy provides a method with superior performance for fluctuating harmonics, but at the same time IEC compliant under stationary conditions.

APA, Harvard, Vancouver, ISO, and other styles

28

Solecki, William, and Cynthia Rosenzweig. "Climate Change, Extreme Events, and Hurricane Sandy: From Non-Stationary Climate to Non-Stationary Policy." Journal of Extreme Events 01, no. 01 (August 2014): 1450008. http://dx.doi.org/10.1142/s2345737614500080.

Full text

Abstract:

This paper illustrates and examines the development of a flexible climate adaptation approach and non-stationary climate policy in New York City in the post-Hurricane Sandy context. Extreme events, such as Hurricane Sandy, are presented as learning opportunities and create a policy window for outside-of-the-box solutions and experimentation. The research investigates the institutionalization of laws, standards, and codes that are required to reflect an increasingly dynamic set of local environmental stresses associated with climate change. The City of New York responded to Hurricane Sandy with a set of targeted adjustments to the existing infrastructure and building stock in a way that both makes it more resistant (i.e., strengthened) and resilient (i.e., responsive to stress) in the face of future extreme events. Post-Sandy New York experiences show that the conditions for a post-disaster flexible adaptation response exist, and evidence shows that the beginnings of a non-stationary policy generation process have been put into place. More broadly, post-disaster policy processes have been configured in New York to enable continuous co-production of knowledge by scientists and the community of decision-makers and stakeholders.

APA, Harvard, Vancouver, ISO, and other styles

29

FELLNER, KLEMENS, and GAËL RAOUL. "STABLE STATIONARY STATES OF NON-LOCAL INTERACTION EQUATIONS." Mathematical Models and Methods in Applied Sciences 20, no. 12 (December 2010): 2267–91. http://dx.doi.org/10.1142/s0218202510004921.

Full text

Abstract:

In this paper, we are interested in the large-time behaviour of a solution to a non-local interaction equation, where a density of particles/individuals evolves subject to an interaction potential and an external potential. It is known that for regular interaction potentials, stable stationary states of these equations are generically finite sums of Dirac masses. For a finite sum of Dirac masses, we give (i) a condition to be a stationary state, (ii) two necessary conditions of linear stability w.r.t. shifts and reallocations of individual Dirac masses, and (iii) show that these linear stability conditions imply local non-linear stability. Finally, we show that for regular repulsive interaction potential Wε converging to a singular repulsive interaction potential W, the Dirac-type stationary states [Formula: see text] approximate weakly a unique stationary state [Formula: see text]. We illustrate our results with numerical examples.

APA, Harvard, Vancouver, ISO, and other styles

30

Lukaševičs, Edmunds, and Ilmārs Kangro. "MATHEMATICAL MODELING OF DIFFUSION BOUNDARY PROBLEMS WITH PERIODIC BOUNDARY CONDITIONS USING MATLAB AND C++ FOR NUMERICAL AND ANALYTICAL SOLUTIONS." HUMAN. ENVIRONMENT. TECHNOLOGIES. Proceedings of the Students International Scientific and Practical Conference, no. 27 (October 30, 2023): 19–27. http://dx.doi.org/10.17770/het2023.27.7373.

Full text

Abstract:

The article examines a second-order parabolic partial differential equation of a three-dimensional (3D) non-stationary boundary problem with constant diffusion coefficients and periodic boundary conditions in the x and y directions. The method for reducing the (3D) non-stationary boundary problem to the corresponding one-dimensional (1D) non-stationary boundary problem using periodic boundary conditions in the x and y directions is discussed. The stationary (analytical) solution of the obtained (1D) stationary boundary problem is also obtained. The numerical solutions of the 1D boundary problem are obtained using the Matlab package "pdepe" and the C++ programming language. As a practical application of the developed mathematical model, the article discusses calculating the concentration of heavy metal Ca in a peat layer based on the obtained experimental data (measurements).

APA, Harvard, Vancouver, ISO, and other styles

31

Ethridge, Don E., Sujit K. Roy, and David W. Myers. "A Markov Chain Analysis of Structural Changes in the Texas High Plains Cotton Ginning Industry." Journal of Agricultural and Applied Economics 17, no. 2 (December 1985): 11–20. http://dx.doi.org/10.1017/s0081305200025012.

Full text

Abstract:

AbstractMarkov chain analysis of changes in the number and size of cotton gin firms in West Texas was conducted assuming stationary and non-stationary transition probabilities. Projections of industry structure were made to 1999 with stationary probability assumptions and six sets of assumed conditions for labor and energy costs and technological change in the non-stationary transition model. Results indicate a continued decline in number of firms, but labor, energy, and technology conditions alter the configuration of the structural changes.

APA, Harvard, Vancouver, ISO, and other styles

32

Krasnov, O. G., and O. K. Bogdanov. "VIBRATIONAL PROCESSES IN THE BALLAST LAYER UNDER NON-STATIONARY LOAD CONDITIONS." World of Transport and Transportation 14, no. 6 (December 28, 2016): 60–77. http://dx.doi.org/10.30932/1992-3252-2016-14-6-7.

Full text

Abstract:

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT This article presents the results of experimental research of vibrational processes in the ballast layer at the depths of 100 mm and 200 mm below the sleeper sole under non-stationary loads caused by percussive interaction between the wheels with faults in the form of flat spots on the tread, and the rails. Dependencies are established of vibrational accelerations on the values of vertical percussive loads on the rail caused by faulty wheels. Keywords: railway track, vibrational processes, non-stationary loading, percussive forces, accelerations, crushed stone fragments, ballast layer, wheel faults.

APA, Harvard, Vancouver, ISO, and other styles

33

Sadeghi Loyeh, Nazanin, and Alireza Massah Bavani. "Daily maximum runoff frequency analysis under non-stationary conditions due to climate change in the future period: Case study Ghareh Sou basin." Journal of Water and Climate Change 12, no. 5 (January 8, 2021): 1910–29. http://dx.doi.org/10.2166/wcc.2021.074.

Full text

Abstract:

Abstract The frequency analysis of the maximum instantaneous flood is mostly based on the stationary assumption. The purpose of the present study is to compare the results of maximum instantaneous flood analysis under stationary and non-stationary conditions in Ghareh Sou basin, and also answer the question as to whether there is a difference between estimating the return period of maximum instantaneous flood in stationary and non-stationary conditions. First, the values of the temperature, wind speed, and rainfall of the study area under the two scenarios of Representative Concentration Pathway (RCP) 2.6 and 8.5 of the Hadley Centre coupled Model, version3 (HadCM3) model were downscaled. In the following, the Variable Infiltration Capacity (VIC) model was utilized to generate daily runoff. For converting the daily discharge to the maximum instantaneous flood, four methods of Fuller, Sangal, Fill Steiner, and artificial neural network (ANN) were compared. Finally, the maximum instantaneous floods of the future period were introduced to the Non-stationary Extreme Value Analysis (NEVA) software. Based on the results obtained from the research, the lack of considering the non-stationary conditions in the flood frequency analysis can result in underestimating the maximum instantaneous flood, which can also provide more risks for the related hydraulic structures.

APA, Harvard, Vancouver, ISO, and other styles

34

Gomez, Jonatan, and Andres Rivera. "Non-Stationary Stochastic Global Optimization Algorithms." Algorithms 15, no. 10 (September 29, 2022): 362. http://dx.doi.org/10.3390/a15100362.

Full text

Abstract:

Studying the theoretical properties of optimization algorithms such as genetic algorithms and evolutionary strategies allows us to determine when they are suitable for solving a particular type of optimization problem. Such a study consists of three main steps. The first step is considering such algorithms as Stochastic Global Optimization Algorithms (SGoals ), i.e., iterative algorithm that applies stochastic operations to a set of candidate solutions. The second step is to define a formal characterization of the iterative process in terms of measure theory and define some of such stochastic operations as stationary Markov kernels (defined in terms of transition probabilities that do not change over time). The third step is to characterize non-stationary SGoals , i.e., SGoals having stochastic operations with transition probabilities that may change over time. In this paper, we develop the third step of this study. First, we generalize the sufficient conditions convergence from stationary to non-stationary Markov processes. Second, we introduce the necessary theory to define kernels for arithmetic operations between measurable functions. Third, we develop Markov kernels for some selection and recombination schemes. Finally, we formalize the simulated annealing algorithm and evolutionary strategies using the systematic formal approach.

APA, Harvard, Vancouver, ISO, and other styles

35

Viloria-Marimón, Orlando M., Álvaro González-Álvarez, and Javier A. Mouthón-Bello. "Analysis of the Behavior of Daily Maximum Rainfall within the Department of Atlántico, Colombia." Water 11, no. 12 (November 22, 2019): 2453. http://dx.doi.org/10.3390/w11122453.

Full text

Abstract:

In the Colombian Caribbean region, there are few studies that evaluated the behavior of one of the most commonly used variables in hydrological analyses: the maximum daily rainfall (Pmax-24h). In this study, multiannual Pmax-24h time series from 19 rain gauges, located within the department of Atlántico, were analyzed to (a) determine possible increasing/decreasing trends over time, (b) identify regions with homogeneous behavior of Pmax-24h, (c) assess whether the time series are better suited under either a stationary or non-stationary frequency analysis, (d) generate isohyetal maps under stationary, non-stationary, and mixed conditions, and (e) evaluate the isohyetal maps by means of the calculation of areal rainfall (Pareal) in nine watersheds. In spite of the presence of both increasing and decreasing trends, only the Puerto Giraldo rain gauge showed a significant decreasing trend. Also, three regions (east, central, and west) with similar Pmax-24h behavior were identified. According to the Akaike information criterion test, 79% of the rain gauges showed better fit under stationary conditions. Finally, statistical analysis revealed that, under stationary conditions, the errors in the calculation of Pareal were more frequent, while the magnitude of the errors was larger under non-stationary conditions, especially in the central–south region.

APA, Harvard, Vancouver, ISO, and other styles

36

Blain, Gabriel Constantino. "Modeling extreme minimum air temperature series under climate change conditions." Ciência Rural 41, no. 11 (November 2011): 1877–83. http://dx.doi.org/10.1590/s0103-84782011001100005.

Full text

Abstract:

Considering the presence of non-stationary components, such as trends, in the extreme minimum air temperature series available from three locations of the State of São Paulo-Brazil, the aim of this research was to describe the probabilistic structure of this variable by using a non-stationary model (based on the general extreme value distribution; GEV model) in which the parameters are estimated as a function of time covariate. The Mann-Kendall test has proven the presence of significant increasing trends in all analyzed series. Furthermore, according to the Pettitt (changing-point) test, 1991 is the initial year of these trends (in the three locations). The applied selection criteria indicated that a GEV model in which the location parameter is estimated as a function of time is recommended to describe the probability structure of the variable under evaluation. The others two parameters of this model remained time-independent. According to this non-stationary model, the detected trends in the climate conditions of these locations have shown the same rate of change (0.04°C per year).

APA, Harvard, Vancouver, ISO, and other styles

37

Vuppalapati, Navya, and T. G. Venkatesh. "Modeling & analysis of software defined networks under non-stationary conditions." Peer-to-Peer Networking and Applications 14, no. 3 (February 2, 2021): 1174–89. http://dx.doi.org/10.1007/s12083-020-01026-w.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Isensee, Leandro José, Adilson Pinheiro, and Daniel Henrique Marco Detzel. "Dam Hydrological Risk and the Design Flood Under Non-stationary Conditions." Water Resources Management 35, no. 5 (March 2021): 1499–512. http://dx.doi.org/10.1007/s11269-021-02798-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Sereda, B. P., I. V. Kruglyak, D. B. Sereda, and D. O. Kruglyak. "RECEIVING PROTECTING COATINGS ON BINDING ALLOYS FOR NON-STATIONARY TEMPERATURE CONDITIONS." Collection of scholarly papers of Dniprovsk State Technical University (Technical Sciences) 2, no. 33 (February 10, 2019): 45–48. http://dx.doi.org/10.31319/2519-2884.33.2018.196.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Palau, J. L., G. Pérez-Landa, and M. M. Millán. "Concatenated non-stationary dispersive scenarios on complex terrain under summer conditions." Atmospheric Chemistry and Physics Discussions 8, no. 3 (June 5, 2008): 10841–72. http://dx.doi.org/10.5194/acpd-8-10841-2008.

Full text

Abstract:

Abstract. The results and discussions presented in this paper arise from a statistically representative study of the physical processes associated with the multimodal distribution of pollutants aloft and around a 343-m-tall chimney under summer conditions in the Iberian Peninsula. The indetermination of a transversal plume to the preferred transport direction during transitional periods implies a small (or null) physical significance of the classical definition of horizontal standard deviation of the concentration distribution. By experimentation and modelling, this paper analyses the atmospheric dispersion of the SO2 emissions from a power plant on complex terrain, describing the main dispersion features as an ensemble of "stationary dispersive scenarios" and reformulating some "classical" dispersive concepts to deal with the systematically monitored summer dispersive scenarios in inland Spain.

APA, Harvard, Vancouver, ISO, and other styles

41

Vu, Thi Thu Nga, Gilbert Teyssedre, and Séverine Le Roy. "Electric Field Distribution in HVDC Cable Joint in Non-Stationary Conditions." Energies 14, no. 17 (August 30, 2021): 5401. http://dx.doi.org/10.3390/en14175401.

Full text

Abstract:

Accessories such as joints and terminations represent weak points in HVDC cable systems. The DC field distribution is intimately dependent on the thermal conditions of the accessory and on material properties. Moreover, there is no available method to probe charge distribution in these conditions. In this work, the field distribution in non-stationary conditions, both thermally and electrically, is computed considering crosslinked polyethylene (XLPE) as cable insulation and different insulating materials (silicone, rubber, XLPE) for a 200 kV joint assembled in a same geometry. In the conditions used, i.e., temperatures up to 70 °C, and with the material properties considered, the dielectric time constant appears of the same order or longer than the thermal one and is of several hours. This indicates that both physical phenomena need to be considered for modelling the electric field distribution. Both the radial and the tangential field distributions are analysed, and focus is given on the field distribution under the stress cone on the ground side and near the central deflector on the high voltage side of the joint. We show that the position of the maximum field varies in time in a way that is not easy to anticipate. Under the cone, the smallest tangential field is obtained with the joint insulating material having the highest electrical conductivity. This results from a shift of the field towards the cable insulation in which the geometrical features produce a weaker axial component of the field. At the level of the central deflector, it is clear that the tangential field is higher when the mismatch between the conductivity of the two insulations is larger. In addition, the field grows as a function of time under stress. This work shows the need of precise data on materials conductivity and the need of probing field distribution in 3D.

APA, Harvard, Vancouver, ISO, and other styles

42

Yusubov, F. V., I. A. Aliyev, and S. N. Guliyeva. "Study of adsorption separation of gas mixtures under non-stationary conditions." Theoretical and Applied Ecology, no. 2 (June 25, 2024): 101–7. http://dx.doi.org/10.25750/1995-4301-2024-2-101-107.

Full text

Abstract:

The influence of the initial concentration, rate and temperature of adsorption on the adsorption separation of gas mixtures (CO2, CH4, N2, H2S) is investigated. Components: N2 – 5%, H2S – 5%, CO2 – 5% and CH4 – 85%. And as an adsorbent granule of clinoptilolite of irregular shape were used. Isothermal adsorption of CO2 was obtained at different temperatures (293, 313, and 323 K). The obtained isotherms of CO2 adsorption showed that with an increase in temperature, the adsorption of CO2 decreased. The type of isotherms corresponds to Langmuir. The output curves of gas mixture adsorption depending on the gas flow rate and various main components of CO2 were also experimentally studied. The output curves of the adsorption of the CO2 component were studied at various gas flow rates of 20, 50, and 80 mL/min. Equilibrium time increases with a decrease in the gas flow rate. Output curves were also obtained depending on the initial CO2 concentrations of 5%, 10% and 20%. It was determined that with a decrease in the initial concentration of CO2, the equilibrium time also increases. Gas mixture components sorbed downwards: H2S→CO2→CH4→N2. The resulting system of model equations describing the adsorption separation of gas mixtures in a fixed adsorbent layer represents a complete mathematical model of the process under unsteady conditions. The obtained regularities of the process of adsorption of gas mixtures testify to the fact that the process takes place under non-stationary conditions. The proposed models for the optimal design of industrial absorbers can be used for adsorption separation of gas mixtures in the conditions of their unsteady flow.

APA, Harvard, Vancouver, ISO, and other styles

43

Idehara, Sérgio Junichi, and Milton Dias Junior. "Modal analysis of rotors with whirling motion under non-stationary conditions." Journal of Sound and Vibration 481 (September 2020): 115445. http://dx.doi.org/10.1016/j.jsv.2020.115445.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Louah, Gérard, and Jean-Marc Morin. "A Problem with Stochastic Traffic Simulation Programs Under Non-Stationary Conditions." IFAC Proceedings Volumes 30, no. 8 (June 1997): 895–900. http://dx.doi.org/10.1016/s1474-6670(17)43935-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Conti, Costanza, and Lucia Romani. "Algebraic conditions on non-stationary subdivision symbols for exponential polynomial reproduction." Journal of Computational and Applied Mathematics 236, no. 4 (September 2011): 543–56. http://dx.doi.org/10.1016/j.cam.2011.03.031.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Afonin, M. A., A. A. Kopyrin, and A. A. Fomichev. "Kinetic model of actinides and lanthanides extraction in non-stationary conditions." Journal of Alloys and Compounds 444-445 (October 2007): 554–56. http://dx.doi.org/10.1016/j.jallcom.2007.03.083.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Kopyrin, A. A., M. A. Afonin, and T. Todd. "Separation of similar elements and isotopes separation in non-stationary conditions." Journal of Alloys and Compounds 444-445 (October 2007): 614–17. http://dx.doi.org/10.1016/j.jallcom.2007.04.226.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Dudek, Sylwia, Piotr Kalita, and Stanisław Migórski. "Stationary flow of non-Newtonian fluid with nonmonotone frictional boundary conditions." Zeitschrift für angewandte Mathematik und Physik 66, no. 5 (June 25, 2015): 2625–46. http://dx.doi.org/10.1007/s00033-015-0545-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Nosrati, Hamed, Mousa Shamsi, Sayed Mostafa Taheri, and Mohammad Hossein Sedaaghi. "Adaptive Networks Under Non-Stationary Conditions: Formulation, Performance Analysis, and Application." IEEE Transactions on Signal Processing 63, no. 16 (August 2015): 4300–4314. http://dx.doi.org/10.1109/tsp.2015.2436363.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Kowalski, S. J., and J. Szadzińska. "Kinetics and Quality Aspects of Beetroots Dried in Non-Stationary Conditions." Drying Technology 32, no. 11 (July 10, 2014): 1310–18. http://dx.doi.org/10.1080/07373937.2014.915555.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!