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Generation of rainfall data series by using the markov chain model in three selected sites in the Kurdistan Region,Iraq

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AI in Civil Engineering 2023年第1期2卷 50-62页

作者： Evan Hajani Gaheen Sarma Water Resource Engineering Department College of EngineeringUniversity of Duhok38 Zakho StreetKurdistan Region 1006 AJDuhok 42001Iraq

Rainfall forecasting can play a significant role in the planning and management of water resource *** study employs a markov chain model to examine the patterns,distributions and forecast of annual maximum rainfall(AMR)data collected at three selected stations in the Kurdistan Region of Iraq using 32 years of 1990 to 2021 rainfall data.A stochastic process is used to formulate three states(i.e.,decrease-"d";stability-"s";and increase-"i")in a given year for estimating quantitatively the probability of making a transition to any other one of the three states in the following year(s)and in the long *** addition,the markov model is also used to forecast the AMR data for the upcoming five years(i.e.,2022-2026).The results indicate that in the upcoming 5 years,the probability of the annual maximum rainfall becoming decreased is 44%,that becoming stable is 16%,and that becoming increased is 40%.Furthermore,it is shown that for the AMR data series,the probabilities will drop slowly from 0.433 to 0.409 in about 11 years,as indi-cated by the average data of the three *** study reveals that the markov model can be used as an appropri-ate tool to forecast future rainfalls in such semi-arid areas as the Kurdistan Region of Iraq.

关键词： Time series Rainfall markov chain Forecast Transition Probability

Ecological Classroom Model for Vocabulary Teaching Based on markov chain

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Sino-US English Teaching 2023年第4期20卷 123-136页

作者： Ge Shuanglin Yang Yu Universiti Putra Malaysia SerdangMalaysia

This paper explores the current English vocabulary teaching classroom based on an eco-linguistic perspective and the markov chain,points out the ecological imbalance in the English vocabulary classroom,and proposes measures to solve the problem and strategies to build an ecological English vocabulary learning classroom,in order to provide some reference for future English vocabulary curriculum reform and curriculum *** this paper,a random sample of 20 students from each class was taken from an advanced arts class and an advanced science *** results show that after a semester of teaching process,the overall English scores of the arts and science classes improved,and since,the arts classes improved more and the teachers’teaching quality was better.

关键词： eco-linguistics markov chain English vocabulary teaching teaching quality

Using the markov chain for the Generation of Monthly Rainfall Series in a Semi-Arid Zone

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Open Journal of Modern Hydrology 2016年第2期6卷 51-65页

作者： Mouelhi Safouane Nemri Saida Jebari Sihem Slimani Mohamed Laboratoire Hydrologie-CES Ariana Tunisie Institut National de Recherches en Génie Rural Eaux et Forêt (INRGREF) Ariana Tunisie Laboratoire des Sciences et Techniques de l’Eau Institut National Agronomique de Tunisie Tunis-Mahrajène Tunisie

Numerous methodologies have been developed in the literature for the generation of rain. However, in semi-arid areas where the irregularity of rain is contrasted, the question of the applicability of these models is still relevant. The objective of this article is to propose a development method of stochastic generator of monthly rainfall series. The present work is based on the modeling of the occurrence and the quantity of rain in a separate way. The occurrence is treated in two stages. The first step considers the markov chain according to the occurrence of annual statements (dry, average and wet). The second step uses the monthly rankings. The amount of rain is calculated based on historical series according to the monthly rank and the annual statement noted. This method is applied to rainfall data recorded at five rainfall stations in semi-arid region of Central Tunisia. The usual and conventional statistical tests of the generated series have shown the validity of this method.

关键词： Stochastic Generation Rainfall Series markov chain Semiarid Central Tunisia

Research and Simulate the Queuing Systems Based on the markov chain

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海外英语 2020年第19期 279-281页

作者：梁天泓西交利物浦大学

This paper shows the researches of the queuing theory,especially the markov chainand the Poison Process,and implements the efficient way of designing the queuing *** simulating the queuing systems based on the“Simply package”in the“Python”programming *** the paper would discuss and analyze the differences between different queuing systems.

关键词： markov chain queuing theory Poison Process

Support Vector Machines(SVM)-markov chain Prediction Model of Mining Water Inflow

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Agricultural Science & Technology 2017年第8期18卷 1551-1554,1558页

作者： Kai HUANG Chizhou Land and Resources Planning and Surveying Institute Chizhou 247000China

This study was conducted to establish a Support Vector Machines(SVM)-markov chain prediction model for prediction of mining water inflow. According to the raw data sequence, the Support Vector Machines(SVM) model was built, and then revised by means of a markov state change probability matrix. Through dividing the state and analyzing absolute errors and relative errors and other indexes of the measured value and the fitted value of SVM, the prediction results were improved. Finally,the model was used to calculate relative errors. Through predicting and analyzing mining water inflow, the prediction results of the model were satisfactory. The results of this study enlarge the application scope of the Support Vector Machines(SVM) prediction model and provide a new method for scientific forecasting water inflow in coal mining.

关键词： Mining water inflow Support Vector Machines (SVM) markov chain

Study on the Prediction Method of the First Heavy Rain in the Spring of Xi'an City Based on markov chain

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Meteorological and Environmental Research 2011年第5期2卷 1-2,6页

作者： QU Jing Xi’an Meteorological Administration,Xi’an 710016,China

[Objective] The aim was to study the markov chain prediction method of first heavy rain in spring in Xi’an City.[Method] According to the dependent random variables of the occurrence of heavy rain,precipitation in spring in seven meteorological stations in Xi’an City from 1959 to 2010 was *** occurrence date was determined by the standard of first heavy rain in spring in *** to the length of the sequence of the problem and actual situation,six states were *** by dint of markov chain,first heavy rain prediction model in spring was set up.[Result] The predicted occurrence time of first heavy rain in spring in Xi’an in 2009 and 2010 was consistent with the actual *** prediction effect was *** method had clear thought and was convenient for calculation,with certain dependence and practicality.[Conclusion] This method provided reference value for the actual forecast of first heavy rain in spring.

关键词： Prediction Spring first heavy rain markov chain China

Improvement of markov chain Model for Occurrence Degree Prediction of Myzus persicae (Sulzer) and Its Application

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Journal of Northeast Agricultural University(English Edition) 2008年第4期15卷 1-5页

作者： REN Guangwei WANG Xiufang WANG Xinwei ZHOU Xiansheng DONG Xiaowei Tobacco Institute Chinese Academy of Agricultural Sciences Qingdao 266101 Shandong China Technology Center Shandong Tobacco Industry Corporation Jinan 250013 China

For long-term prediction of occurrence degree of tobacco aphid Myzus persicae （Sulzer）, markov chain method was used to establish prediction model for occurrence degree of tobacco aphid. With 4 levels of occurrence degree, markov chain model was established based on the data in 1987-2004. The results indicated that the accuracy for total prediction in 2005-2007 and the back prediction in 1987-2004 reached 88.89% and 85.12%, respectively. The method is simple and feasible for long-term prediction of occurrence degree of tobacco aphid.

关键词： Myzus persicae (Sulzer) markov chain prediction occurrence degree

Convergence Analysis of Cuckoo Search by Creating markov chain

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Journal of Donghua University(English Edition) 2016年第6期33卷 973-977页

作者： ZHOU Hui CHENG Ya-qiao LI Dan-mei XU Chen College of Electronic Information Nantong UniversityNantong 226019China College of lnformation Science and Technology Donghua UniversityShanghai 201620China

Cuckoo search(CS) has been used successfully for solving global optimization *** a theoretical point of view,the convergence of the CS is an important *** this paper,convergence analysis of CS was *** transition probability characteristics of the population to construct a markov chain were *** homogeneity of the markov chain was derived based on stochastic process *** it was proved to be an absorbing state markov ***,the global convergence of CS was deduced based on conditions of convergence sequence and total probability formula,and the expected convergence time was ***,a series of experiments were *** results were analyzed and it is observed that CS seems to perform better than PSO.

关键词： cuckoo search(CS) global convergence markov chain expected convergence time

Research on Prediction Model and Method of Power Output of Photovoltaic Power Plant Based on Neural Network and markov chain

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Research on Prediction Model and Method of Power Output of P...